Dear Dima
I just made a very quick search for references on corundum+petrology,
the result is attached as a file which can be opened with MS Word.

All the best
Leif

> Dmitry Krylov wrote:
>
> Dear all,
> I am searching for references on corundum-bearing rocks, preferably in
> Precambrian (petrology, petrochemistry, geochemistry, origins). Would
> be grateful for any comments.
>
> Regards,
>
> D.P. Krylov, Dr. Sci.
> Inst. Precambrian Geology & Geochronology
> Russian Academy of Sciences
> nab. Makarova, 2
> 199034, St. Petersburg
> Russian Federation


Search History
*  #2 corundum and petrology (393 records)
   #1 corundum precambrian petrology (0 records)


Record 1 of 393 in GEOBASE 1997/12-2001/08

TI:  Enstatite-sapphirine crack-related assemblages in ultrahigh-pressure pyrope megablasts, Dora-Maria massif, western Alps.
AU:  Simon-G.; Chopin-C.
SO:  Contributions-to-Mineralogy-and-Petrology. 2001; 140(4): 422-440
FTXT:  Springer-Verlag LINK (European Mirror) http://link.springer.de/cgi/linkref?issn=0010-7999&year=2001&volume=140&page=422 Springer-Verlag LINK (US Mirror) http://link.springer-ny.com/cgi/linkref?issn=0010-7999&year=2001&volume=140&page=422 Springer Search http://link.springer.de/search.htm /cgi/linkref?issn=0010-7999&year=2001&volume=140&page=422 SwetsNet (European Mirror) http://www.swetsnet.nl/link/access_db?issn=00107999&vol=00140&iss=00004&page=422 SwetsNet (US Mirror) http://www.swetsnet.com/link/access_db?issn=00107999&vol=00140&iss=00004&page=422 EBSCO Online http://www.ebsco.com/online/direct.asp?ArticleID=YK4XY421QUYX94A479MC InformationQuest http://www.eiq.com/usr_login.html?sici=0010-7999%28000000%29140%3A4%3C422%3AX%3E2.0.CO%3B2-X
AB:  Throughout the ultrahigh-pressure (UHP) metamorphic unit of the Dora-Maira massif, western Alps, pyrope megablasts contain the typical assemblage clinochlore-kyanite-talc-rutile ± phlogopite ± ellenbergerite as prograde inclusions. In the upper part of the UHP unit in Val Gilba, some megablasts (XMg = 0.89-0.98) contain in addition polymineralic inclusions consisting of various combinations of enstatite, gedrite, sapphirine, clinochlore, talc, magnesiostaurolite and rare corundum or spinel. We present evidence that these assemblages developed from cracks running across the megablasts, and are therefore of late origin, post-dating the highest-pressure stage. Enstatite (XMg = 0.94-0.99) contains 0.7 to, typically, 3 wt% Al<inf>2</inf>O<inf>3</inf>, but up to 8.4 wt% in the presence of sapphirine. Sapphirine (XMg = 0.96-0.998, Be-free) shows the largest compositional variations, with Si contents ranging from 1.7 to at least 2.1 atoms pfu, thereby clearly exceeding the 2:2:1 stoichiometry. The late-stage talc contains up to 4 wt% Al<inf>2</inf>O<inf>3</inf>, 0.35 wt% Na<inf>2</inf>O and 0.6 wt% F; gedrite 1.1-2.9 wt% Na<inf>2</inf>O and up to 0.36 wt% F. The successive development within pyrope of alternative hydrous assemblages involving first enstatite plus an Al-rich phase (kyanite, sapphirine, magnesiostaurolite) ± clinochlore, then a gedrite compositionally close to pyrope, then talc plus an Al-rich phase (sapphirine, corundum), is a clear record of decompression. However, the temperature conditions implied under the assumption of high H<inf>2</inf>O activity are 100 to 150 < degrees >C higher than, and so inconsistent with existing constraints on the decompression path. These constraints are in particular the stability of talc + phengite in the matrix assemblage during decompression, and the absence of regional evidence for a granulite-facies event. This inconsistency can only be alleviated if H<inf>2</inf>O activity inside the garnet megablast was (or became) considerably reduced with respect to that in the matrix. Fluid influx into an opening fracture in garnet, sealing of the fracture by breakdown products of pyrope and continued evolution under closed-system conditions may have led to increasing solute concentration and such low H<inf>2</inf>O activity within the garnet megablast, driving the microsystem toward fluid-absent conditions. Micrometre-size inclusions of Casulfate and crandallite-type compounds in minerals of these reactive areas may be evidence for such residual brines and suggest that these were phosphate- and sulfate-rather than halide-dominated. This finding is additional evidence for the very local control that fluid composition and H<inf>2</inf>O activity may have on the occurrence of granulite-facies assemblages, regardless of temperature. It highlights the role of deformation (here fracturing) in triggering reactions in otherwise unreactive systems. It also shows how carefully inclusion-to-host relationships have to be considered, post-growth reaction within the host being more common than hitherto reported.
AN:  2310683

Record 2 of 393 in GEOBASE 1997/12-2001/08

TI:  Proterozoic plutonism in Antarctica: The Granito Bertrab and its assiciated dyke-swarms.
OT:  Plutonismo proterozoico en Antartida: El Granito Bertrab y su cortejo de diques.
AU:  Acevedo-R.D.; Linares-E.; Valin-Alberdi-M.L.; Ostera-H.; Martin-Izard-A.
SO:  Revista-de-la-Asociacion-Geologica-Argentina. 2000; 55(3): 179-187
AB:  Bertrab Nunatak is located in the Vahsel Bay area, Weddell Sea, Antarctica. It is composed of a granitic body, < much-less-than >Granito Bertrab< much-greater-than >, cut by acid-(aplite/rhyolite and quartz veins) and basic dyke-swarms. Granito Bertrab is a coarse-grained, granophyric quartz-feldsparbiotite granite with minor normative corundum (1%) that indicates peraluminous affinities. Melanocratic calc-alkaline dykes, with labradorite-andesine and amphibole megacrysts, have a lamprophyric character. One of these is cut by a leucocratic dike, that represents the final stage in the magmatic activity. Petrological evidence indicates that there is a temporally, spatially and genetically intimate association between the granite and the dykes. K-Ar data on samples of the granite give an age of 996 = 40 Ma, and the Rb-Sr isochron age recalculated using the published data of Eastin and Faure give an age of 971 ± 8 Ma using five samples, and 992 ± 12 Ma when the aplitic member is not included. These results are in good agreement with the K-Ar age and mean that the Granito Bertrab was emplaced in the late Mesoproterozoic.
AN:  2309954

Record 3 of 393 in GEOBASE 1997/12-2001/08

TI:  Margarite-corundum phyllites from the Appalachian orogen of South Carolina: Mineralogy and metamorphic history.
AU:  Ranson-W.A.
SO:  American-Mineralogist. 2000; 85(11-12): 1617-1624
AB:  Phyllites from the Charlotte belt (Central Piedmont) of South Carolina contain porphyroblasts of black corundum in a matrix of margarite and minor muscovite. The margarite-corundum phyllites formed during Ordovician (?) amphibolite facies metamorphism of an aluminous protolith with a probable mineralogy of pyrophyllite, diaspore, and calcite through reactions such as 6Dia + Prl + 2Cal = 2Mrg + 2CO<inf>2</inf> + 2H<inf>2</inf>O and 2Dia = Crn + H<inf>2</inf>O. The protolith was probably a hydrothermally altered felsic tuff of Late Proterozoic to Cambrian age. Based on a whole-rock chemical analysis of margarite-corundum phyllite, the protolith is believed to have consisted of about 7 mol% calcite, 23 mol% pyrophyllite, and 70 mol% diaspore. A T-X<inf>CO2</inf> plot of pertinent reactions in the system CaO-Al<inf>2</inf>O<inf>3</inf>-SiO<inf>2</inf>-H<inf>2</inf>O-CO<inf>2</inf> shows that in the presence of an H<inf>2</inf>O-rich fluid (X<inf>CO2</inf> < similar-to >0.08) margarite began forming by the reaction 6Dia + Prl + 2Cal = 2Mrg + 2CO<inf>2</inf> + 2H<inf>2</inf>O at about 350 < degrees >C at 5 kbar. This reaction continued along a univariant path until pyrophyllite and calcite were consumed. The remaining diaspore was converted to corundum by the reaction 2Dia = Crn + H<inf>2</inf>O at about 430 < degrees >C for this H<inf>2</inf>O-rich fluid at 5 kbar. The upper temperature limit of this assemblage is constrained by the reaction Mrg = Crn + An + H<inf>2</inf>O, which should occur at about 575 < degrees >C under this pressure. The absence of plagioclase in these rocks suggests that the conditions of this reaction were never achieved. Fluids associated with subsequent Alleghanian greenschist facies metamorphism reacted with corundum to form fine-grained margarite at corundum margins.
AN:  2304133

Record 4 of 393 in GEOBASE 1997/12-2001/08

TI:  The effect of Cr on the solubility of Al in orthopyroxene: Experiments and thermodynamic modelling.
AU:  Klemme-S.; O'-Neill-H.St.C.
SO:  Contributions-to-Mineralogy-and-Petrology. 2000; 140(1): 84-98
FTXT:  EBSCO Online http://www.ebsco.com/online/direct.asp?ArticleID=M069THTE8KBX9L10H25Q Springer-Verlag LINK (European Mirror) http://link.springer.de/cgi/linkref?issn=0010-7999&year=2000&volume=140&page=84 Springer-Verlag LINK (US Mirror) http://link.springer-ny.com/cgi/linkref?issn=0010-7999&year=2000&volume=140&page=84 Springer Search http://link.springer.de/search.htm /cgi/linkref?issn=0010-7999&year=2000&volume=140&page=84 SwetsNet (European Mirror) http://www.swetsnet.nl/link/access_db?issn=00107999&vol=00140&iss=00001&page=84 SwetsNet (US Mirror) http://www.swetsnet.com/link/access_db?issn=00107999&vol=00140&iss=00001&page=84 InformationQuest http://www.eiq.com/usr_login.html?sici=0010-7999%28000000%29140%3A1%3C84%3AX%3E2.0.CO%3B2-X
AB:  The partitioning of chromium and aluminium between coexisting orthopyroxene and spinel in equilibrium with forsterite in the system MgO-Al<inf>2</inf>O<inf>3</inf>-SiO<inf>2</inf>-Cr<inf>2</inf>O<inf>3</inf> (MAS-Cr) has been experimentally determined as a function of temperature, pressure and Cr/(Cr + Al) ratio. Experiments were conducted at temperatures between 1300 and 1500 < degrees >C and at pressures from 5 to 54 kbar. Previous experimental results on the (Al, Cr)<inf>2</inf>O<inf>3</inf> and Mg(Al, Cr)<inf>2</inf>O<inf>4</inf> solid solutions have been combined with the present results plus relevant data from the CMAS system to derive a thermodynamic model for Al-Cr-bearing orthopyroxenes, spinels and corundum-esk-olaite solid solutions. The orthopyroxene solid solution can be modelled within the accuracy of all experimental constraints as a ternary solid solution involving the components Mg<inf>2</inf>Si<inf>2</inf>O<inf>6</inf> ( E), MgAl<inf>2</inf>SiO<inf>6</inf> (M) and MgCr<inf>2</inf>SiO<inf>6</inf> (C), in which the activities are related to composition through the equations: where n(Al) and n(Cr) are the number of Al and Cr cations per orthopyroxene formula unit of six oxygens. These expressions reduce to one-site mixing for Mg<inf>2</inf>Si<inf>2</inf>O<inf>6</inf>-MgAl<inf>2</inf>SiO<inf>6</inf> orthopyroxenes in the Cr-free system, but are equivalent to two-site mixing for the exchange of Al and Cr between orthopyroxene and spinel, as required by the experimental data. We find W(EM)(opx) = W(EC)(opx) 20 kJ mol<sup>-1</sup> and W(MC)(opx) = 0.
AN:  2298034

Record 5 of 393 in GEOBASE 1997/12-2001/08

TI:  Pressure-temperature evolution of retrogressed kyanite eclogites, Weinschenk Island, North-East Greenland Caledonides.
AU:  Elvevold-S.; Gilotti-J.A.
SO:  Lithos. 2000; 53(2): 127-147
FTXT:  SwetsNet (European Mirror) http://www.swetsnet.nl/link/access_db?issn=00244937&vol=00053&iss=00002&page=127 SwetsNet (US Mirror) http://www.swetsnet.com/link/access_db?issn=00244937&vol=00053&iss=00002&page=127 ScienceDirect (tm) http://www.sciencedirect.com/science?_ob=GatewayURL&_origin=SilverLinker&_urlversion=4&_method=citationSearch&_volkey=0024%2d4937%2353%23127%232&_version=1&md5=0e7af485bef7f4703eaa44418ced37f2
AB:  Caledonian eclogites and associated high-pressure rocks are present in a 400 X 100-km long belt along the coast of North-East Greenland. Kyanite and clinozoisite eclogites on Weinschenk Island (77< degrees >54'N, 21< degrees >17'W) occur as lenses within amphibolite facies, quartzofeldspathic gneisses. The eclogites have been extensively overprinted by lower pressure assemblages and exhibit a variety of coronitic and symplectitic reaction textures that record the exhumation path of the rocks. Textural relationships and mineral composition data indicate that the initial high-pressure, plagioclase-free assemblage was garnet + omphacite ± kyanite ± clinozoisite + rutile. Compositional growth zoning in garnet, together with distribution of mineral inclusions within it, record a prograde evolution from epidote-amphibolite facies progressing into the eclogite facies. Post-peak pressure reaction textures include clinopyroxene-plagioclase intergrowths after omphacite; the replacement of kyanite by sapphirine-plagioclase, spinel-plagioclase and corundum-plagioclase symplectites; and resorption of garnet by amphibole-plagioclase kelyphites. The replacement textures indicate that post-eclogite facies decompression took place while the rocks remained at elevated temperatures (upper amphibolite/granulite facies conditions). The metamorphic evolution of the eclogites is in agreement with eclogite formation by thick-skinned crustal imbrication and subhorizontal shortening of the Laurentian margin during Caledonian collision, exhumation to amphibolite facies by emplacement of the eclogite-bearing thrust sheet on the Laurentian margin and accompanying erosion, and final exhumation to the surface by post-Caledonian crustal thinning. (C) 2000 Elsevier Science B.V. All rights reserved.
AN:  2276246

Record 6 of 393 in GEOBASE 1997/12-2001/08

TI:  The late stages of evolution of the Kwandonkaya A-type granite complex, Nigeria, as deduced from mafic minerals.
AU:  Sakoma-E.M.; Martin-R.F.; Williams-Jones-A.E.
SO:  Journal-of-African-Earth-Sciences. 2000; 30(2): 329-350
FTXT:  SwetsNet (European Mirror) http://www.swetsnet.nl/link/access_db?issn=08995362&vol=00030&iss=00002&page=329 SwetsNet (US Mirror) http://www.swetsnet.com/link/access_db?issn=08995362&vol=00030&iss=00002&page=329 ScienceDirect (tm) http://www.sciencedirect.com/science?_ob=GatewayURL&_origin=SilverLinker&_urlversion=4&_method=citationSearch&_volkey=0899%2d5362%2330%23329%232&_version=1&md5=6064adfd824b8ff7c1ec83633976102c
AB:  In the Kwandonkaya Complex, an A-type metaluminous to peraluminous granite complex in northern Nigeria, the presence of Fe<sup>2</sup><sup>+</sup>-rich ferromagnesian phases (fayalite, hedenbergite and amphibole) at the initial and annite at final stages of crystallisation indicates relatively reduced melts throughout (_QFM). Annite and associated species in the biotite granites provide the best indication as to the nature of volatile loss, albitisation and greisen formation. From the mica chemistry, it is inferred that degassing was accompanied by preferential loss of Cl in the roof zones and margins of the plutonic rocks, with the resulting enrichment of F and inferred Li in mica from the drusy facies. During albitisation, the mica composition was rock-buffered with respect to major constituents like Fe. However, the F ± (Li, REE, Y, Nb, Ta, Sn) contents were enhanced during albitisation to produce F-rich mica associated with disseminated-type topaz-columbite-cassiterite mineralisation. Greisen formation was accompanied by the build-up of Si, Al, Ti, F and possibly Li, which is in agreement with enhanced normative quartz and corundum, and increases in modal mica, quartz, topaz and fluorite. The mafic minerals and their alteration assemblages indicate that volatile loss, incipient subsolidus modifications, albitisation and greisen formation were associated with increases in f(HF) and f(H2O). Both oxidation and preferential Cl loss promoted the deposition of cassiterite at post-magmatic stages. (C) 2000 Elsevier Science Limited. All rights reserved.
AN:  2259407

Record 7 of 393 in GEOBASE 1997/12-2001/08

TI:  Edgarite, FeNb<inf>3</inf>S<inf>6</inf>, first natural niobium-rich sulfide from the Khibina alkaline complex, Russian Far North: Evidence for chalcophile behavior of Nb in a fenite.
AU:  Barkov-A.Y.; Martin-R.F.; Men'-shikov-Y.P.; Savchenko-Y.E.; Thibault-Y.; Laajoki-K.V.O.
SO:  Contributions-to-Mineralogy-and-Petrology. 2000; 138(3): 229-236
FTXT:  EBSCO Online http://www.ebsco.com/online/direct.asp?ArticleID=HTY3BGN9JJ53G71FAEAK SwetsNet (European Mirror) http://www.swetsnet.nl/link/access_db?issn=00107999&vol=00138&iss=00003&page=229 SwetsNet (US Mirror) http://www.swetsnet.com/link/access_db?issn=00107999&vol=00138&iss=00003&page=229 Springer-Verlag LINK (European Mirror) http://link.springer.de/cgi/linkref?issn=0010-7999&year=2000&volume=138&page=229 Springer-Verlag LINK (US Mirror) http://link.springer-ny.com/cgi/linkref?issn=0010-7999&year=2000&volume=138&page=229 Springer Search http://link.springer.de/search.htm /cgi/linkref?issn=0010-7999&year=2000&volume=138&page=229 InformationQuest http://www.eiq.com/usr_login.html?sici=0010-7999%28000000%29138%3A3%3C229%3AX%3E2.0.CO%3B2-X
AB:  The new mineral species edgarite, FeNb<inf>3</inf>S<inf>6</inf>, was discovered in a feldspar-rich fenite, in a fenitized xenolith enclosed by nepheline syenite of the Khibina alkaline complex, Kola Peninsula, northwestern Russia. It occurs as platy inclusions (up to 0.15 mm) in Ti-(V)-rich pyrrhotite and ferroan alabandite, and as dark gray aggregates of platy grains located on the surface of the pyrrhotite. The associated minerals include Ti-(V)-rich marcasite, Mn-Fe-rich wurtzite-2H, corundum, nearly end member phlogopite, rutile, monazite-(Ce), and a graphite-like material. Edgarite is soft (VHN(5;10) = 135-205 kg/mm<sup>2</sup>), distinctly bireflectant, and has a strong anisotropy. Its reflectance in air (and in oil) (R<inf>1</inf> and R<inf>2</inf> in percent, respectively) is: 470 nm: 28.1, 40.2 (13.0, 24.2), 546 nm: 27.4, 39.3 (12.3, 22.7), 589 nm: 27.0, 38.5 (12.2, 21.7), and 650 nm: 27.0, 36.9 (12.4, 20.3). The composition is Nb 52.87, Fe 10.12, V 0.36, Mn 0.10, Ti 0.04, S 35.86, sum 99.35 wt%, which corresponds to (Fe<inf>0</inf><inf>.</inf><inf>9</inf><inf>6</inf>V<inf>0</inf><inf>.</inf><inf>0</inf><inf>4</inf>Mn<inf>0</inf><inf>.</inf><inf>0</inf><inf>1</inf>)(< Sigma >1.01)Nb<inf>3</inf><inf>.</inf><inf>0</inf><inf>3</inf>S<inf>5</inf><inf>.</inf><inf>9</inf><inf>5</inf> (basis: < Sigma > atoms = 10). By analogy with synthetic FeNb<inf>3</inf>S<inf>6</inf>, the X-ray powder pattern of edgarite was indexed on a hexagonal cell, a = 5.771(1), c = 12.190(6) <a><ac>A</ac><ac></ac></a>, and V = 351.6(3) <a><ac>A</ac><ac></ac></a><sup>3</sup>, D(calc) is 4.99 g/cm<sup>3</sup>. The space group is most probably P6<inf>3</inf>22, with Z = 2. The strongest lines of the pattern [d in <a><ac>A</ac><ac></ac></a> (I, hkl)] are: 6.11 (8, 002), 3.04 (6, 004), 2.88 (5, 110), 2.606 (8, 112), 2.096 (10, 114), 1.665 (8, 300), 1.524 (6, 008), 1.126 (7, 322), and 1.027 (6, 414). Edgarite appears to have formed at a very late or final stage of metasomatism, after the main event of fenitization, from a highly reduced, subalkaline S-C-H-rich fluid, which may have remobilized Nb as a result of destabilization of oxide minerals. These reducing conditions promoted the chalcophile behavior of lithophile elements (Nb, Ti, V and Mn) on a local scale in the fenite.
AN:  2252571

Record 8 of 393 in GEOBASE 1997/12-2001/08

TI:  Effect of carbon dioxide on dehydration melting reactions and melt compositions in the lower crust and the origin of alkaline rocks.
AU:  Kaszuba-J.P.; Wendlandt-R.F.
SO:  Journal-of-Petrology. 2000; 41(3): 363-386
FTXT:  SwetsNet (European Mirror) http://www.swetsnet.nl/link/access_db?issn=00223530&vol=00041&iss=00003&page=363 SwetsNet (US Mirror) http://www.swetsnet.com/link/access_db?issn=00223530&vol=00041&iss=00003&page=363 EBSCO Online http://www.ebsco.com/online/direct.asp?ArticleID=LLAKPX6A7V7G89692GQ4
AB:  Dehydration melting experiments of alkali basalt associated with the Kenya Rift were performed at 0< middle-dot >7 and 1< middle-dot >0 GPa, 850-1100< degrees >C, 3-5 wt % H<inf>2</inf>O, and f(O<inf>2</inf>) near nickel-nickel oxide. Carbon dioxide [X(CO<inf>2</inf>) = molar CO<inf>2</inf>/(H<inf>2</inf>O + CO<inf>2</inf>) = 0< middle-dot >2-0< middle-dot >9] was added to experiments at 1025 and 1050< degrees >C. Dehydration melting in the system alkali basalt-H<inf>2</inf>O produces quartz and corundum-normative trachyandesite (6-7< middle-dot >5 wt % total alkalis) at 1000 and 1025< degrees >C by the incongruent melting of amphibole (pargasite-magnesiohastingsite). Dehydration melting in the system alkali basalt-H<inf>2</inf>O-CO<inf>2</inf> produces nepheline-normative tephriphonolite, trachyandesite, and trachyte (10< middle-dot >5-12 wt % total alkalis). In the latter case, the solidus is raised relative to the hydrous system, less melt is produced, and the incongruent melting reaction involves kaersutite. The role of carbon dioxide in alkaline magma genesis is well documented for mantle systems. This study shows that carbon dioxide is also important to the petrogenesis of alkaline magmas at the lower pressures of crustal systems. Select suites of continental alkaline rocks, including those containing phonolite, may be derived by low-pressure dehydration melting of an alkali basalt-carbon dioxide crustal system.
AN:  2241406

Record 9 of 393 in GEOBASE 1997/12-2001/08

TI:  Liquidus phase relations in the system CaO-MgO-Al<inf>2</inf>O<inf>3</inf>-SiO<inf>2</inf> at 2.0 GPa: Applications to basalt fractionation, eclogites, and igneous sapphirine.
AU:  Liu-T.-C.; Presnall-D.C.
SO:  Journal-of-Petrology. 2000; 41(1): 3-20
FTXT:  SwetsNet (European Mirror) http://www.swetsnet.nl/link/access_db?issn=00223530&vol=00041&iss=00001&page=3 SwetsNet (US Mirror) http://www.swetsnet.com/link/access_db?issn=00223530&vol=00041&iss=00001&page=3 EBSCO Online http://www.ebsco.com/online/direct.asp?ArticleID=9V2P81VL8E4728VH4F06
AB:  To model magmatic crystallization processes for mafic to intermediate compositions at high pressure, liquidus phase relations in the forsterite-anorthite-diopside-silica (FADS) tetrahedron within the CaO-MgO-Al<inf>2</inf>O<inf>3</inf>-SiO<inf>2</inf> system have been determined at 2.0 GPa. Compositions of five liquidus invariant points have been determined and the approximate compositions of five others have been inferred. These involve primary phase volumes for forsterite (fo), enstatite (en), diopside (di), high quartz (qz), spinel (sp), sapphirine (sa), garnet (gt), anorthite (an), and corundum (cor). The determined (with wt % coefficients) and inferred reactions (without coefficients) that define each isobaric invariant point are as follows: 23 en + 68 di + 9 sp = 84 liq + 16 fo 37 di + 63 sa = 47 liq + 40 sp + 13 en 100 gt = 21 liq + 27 sa + 55 en - 18 di 1 di + 59 en + 41 an = 43 liq + 57 gt 18 di + 21 qz + 15 en + 47 an = 100 liq di + an + gt = liq + sa an + gt = liq + sa + en sa + an + di = liq + sp sa + an = liq + cor + sp di + cor = liq + an + sp. These phase relations provide a diverse range of constraints on igneous processes at pressures near 2 GPa. They show that fractional crystallization of a model basalt gives a residual liquid strongly enriched in SiO<inf>2</inf>, strongly depleted in MgO, and mildly enriched in Al<inf>2</inf>O<inf>3</inf>. Such a trend is consistent with the calc-alkaline fractionation trend observed at subduction zones, but is in disagreement with suggestions that fractionation of tholeiitic basalt in this pressure range yields an alkalic basalt. Both trends may occur for natural basalts depending on the Na<inf>2</inf>O content of the parental magma. Also, the data show that the minimum pressure for the formation of cumulate eclogites and garnet pyroxenites is about 1.8-1.9 GPa. The lower limit of pressure at which sapphirine can crystallize from a liquid in the FADS tetrahedron is estimated to be 1.1-1.5 GPa and the upper limit is >3 GPa. Sapphirine crystallizes from magmas intermediate in composition between basalt and andesite. Probable igneous sapphirine in mafic associations is rare, but it occurs as part of a pyroxenite xenolith from Delegate, Australia, that we suggest is a cumulate assemblage and in a sapphirine norite at Wilson Lake, Labrador, Canada.
AN:  2234683

Record 10 of 393 in GEOBASE 1997/12-2001/08

TI:  Importance of fracturing during retro-metamorphism of eclogites.
AU:  Straume-A.K.; Austrheim-H.
SO:  Journal-of-Metamorphic-Geology. 1999; 17(6): 637-652
FTXT:  EBSCO Online http://www.ebsco.com/online/direct.asp?ArticleID=4NN8HN0UXR9B9NPCLG04 SwetsNet (European Mirror) http://www.swetsnet.nl/link/access_db?issn=02634929&vol=00017&iss=00006&page=637 SwetsNet (US Mirror) http://www.swetsnet.com/link/access_db?issn=02634929&vol=00017&iss=00006&page=637
AB:  Presented textural and petrological data show that the deep to intermediate continental crust may fracture and that microfractures are the locus of fluid and mass transfer necessary for retrograde metamorphism. Kyanite eclogites from Ulsteinvik, Norway, underwent partial retrogression to granulite and amphibolite facies assemblages during near-isothermal exhumation from depths equivalent to more than 2.0 GPa at temperatures of 700-800 < degrees >C. Plagioclase-bearing assemblages, rich in hydrous phases, formed along margins of eclogite lenses and along mesoscopic fracture systems. Hydrated zones are from 1-50 cm thick, with adjacent wall-rock eclogite replaced by symplectites. At a low degree of reaction, the secondary minerals in the wall-rock are found along intra- and intergranular microfractures (typically 50-100 < mu >m wide). Minerals filling the microfractures include orthopyroxene-plagioclase-spinel in garnet; plagioclase-sapphirine, plagioclase-corundum and plagioclase-spinel in kyanite; and diopside-plagioclase in omphacite. The microfractures are often arranged en echelon and are connected through microfaults. Releasing bends filled with amphibole and spinel from along microfaults in garnet. The faulting and fracturing caused localized chemical change in garnet: the damage zones close to faults are enriched in FeO and MnO with steep compositional gradients (8 wt% FeO over <20 < mu >m). These FeO- and MnO-enriched zones form wedge-like structures around the tip of the faults (horsetail structures) and rose- or flame-like structures at sticking points along faults. They may represent examples of stress-induced chemical transport during fracture propagation. The change from dry to amphibole-bearing assemblages at the tip of the fracture, and fractures ending in splays of fluid inclusions trails, reflect the involvement of a fluid phase during fracture propagation. This suggests that the 'dry' granulite facies retrogression was also driven by fluid infiltration and that metamorphism at depth in collision zones may not be controlled by pressure and temperature alone.
AN:  2226703

Record 11 of 393 in GEOBASE 1997/12-2001/08

TI:  High temperature stability limit of phase egg, AlSiO<inf>3</inf>(OH).
AU:  Ono-S.
SO:  Contributions-to-Mineralogy-and-Petrology. 1999; 137(1-2): 83-89
FTXT:  InformationQuest http://www.eiq.com/usr_login.html?sici=0010-7999%28000000%29137%3A1-2%3C83%3AX%3E2.0.CO%3B2-X
AB:  The stability relations of phase egg, AlSiO<inf>3</inf>(OH), have been investigated at pressures from 7 to 20 GPa, and temperatures from 900 to 1700 < degrees >C in a multi-anvil apparatus. At the lower pressures phase egg breaks down according to the univariant reaction, phase egg = stishovite + topaz-OH, which extends from 1100 < degrees >C at 11 GPa to 1400 < degrees >C at 13 GPa where it terminates at an invariant point involving corundum. At pressures above the invariant point, the stability of phase egg is limited by the breakdown reaction, phase egg = stishovite + corundum + fluid, which extends from the invariant point to 1700 < degrees >C at 20 GPa. Stishovite crystallized in the Al<inf>2</inf>O<inf>3</inf>-SiO<inf>2</inf>-H<inf>2</inf>O system contains Al<inf>2</inf>O<inf>3</inf>, and the amount of Al<inf>2</inf>O<inf>3</inf> increases with increasing temperature. It is inferred that the Al<inf>2</inf>O<inf>3</inf> content is controlled by the charge-balanced substitution of Si<sup>4</sup><sup>+</sup> by Al<sup>3</sup><sup>+</sup> and H<sup>+</sup>. Aluminum-bearing stishovite coexisting with an H<inf>2</inf>O-rich fluid may contain a certain amount of water. Therefore, phase egg and stishovite in a subducting slab could transport some H<inf>2</inf>O into the deep Earth.
AN:  2221765

Record 12 of 393 in GEOBASE 1997/12-2001/08

TI:  Denudation of lithospheric subcontinental mantle at the Adria margin of the piemontese ocean belt (Malenco, Italy).
AU:  Trommsdorff-V.; Hermann-J.; Muntener-O.
SO:  Ofioliti. 1999; 24(1 A): 182
AB:  Major metaperidotite bodies of the Central and Western Alps and of Liguria are former subcontinental Adriatic lithosphere (Piccardo et al., 1992; Lemoine et al., 1987; Trommsdorff et al., 1993). One of the largest masses of metaperidotite occurs at Val Malenco, Eastern Central Alps, with a surface area of over 130 km<sup>2</sup>. It is composed dominantly of fertile and depleted spinel lherzolites and of subordinate amounts of dunite; corundum bearing garnet clinopyroxenite and phlogopite hornblendite (Muntener, 1997). There is clear geological and petrological evidence for a pre-oceanic subcontinental setting of the Malenco mantle and for Jurassic emplacement and denudation within the Piemontese ocean basin. The evidence may be summarized as follows: The Malenco mantle is in part overlain by a lower crustal granulite complex consisting of kyanite-garnet rocks; migmatites; wollastonite bearing calc-silicate rocks and olivine-spinel marbles. Pelitic granulites and mantle rocks are crosscut and welded together by a gabbro complex, the Braccia Gabbro (Hermann, 1997), which is of Lower Permian age (Hansmann et al., 1996). After the gabbro intrusion the complex underwent granulite facies equilibration. This crust mantle transition was stable at 25-30 km depth for a period of over 50 million years (Hermann et al., 1997), and then was rapidly exhumed during Jurassic rifting. During this process large parts of the Malenco mantle were emplaced in the Piemontese ocean basin and denuded. Proof of this is provided by ophicarbonate rocks that were deposited on top of the Malenco mantle as fracture fillings and as debris flows containing blocks of serpentinized lherzolite and, at some localities, of platform carbonate sediments. The western parts of the Malenco mantle rocks are intruded and overlain by MOR-type basalts which form the basis of a Jurassic to Cretaceous, oceanic sedimentary sequence, the Forno unit. During its oceanic stage the Malenco mantle was partly serpentinized and, concomitantly, metarodingites formed from the Permian gabbro and Jurassic MORB dykes within the mantle rocks. It is suggested on the basis of structural geological arguments that the Malenco mantle was exhumed along a lithosphere-scale shear zone that dipped towards the Adriatic continent. This shear zone is preserved in exposures extending several kilometers. The shear zone contains in its brittle part components of crustal and mantle rocks (Ur-breccia, Trommsdorff et al., 1993). The fossil Malenco margin thus resembles in all its properties the modern Galicia margin of the Atlantic ocean described by Boillot et al. (1995).
AN:  2219293

Record 13 of 393 in GEOBASE 1997/12-2001/08

TI:  Evolution of the Horoman peridotite complex and its implications for the origin of heterogeneous mantle.
AU:  Morishita-T.; Arai-S.
SO:  Ofioliti. 1999; 24(1 A): 137-138
AB:  Mantle heterogeneity is very important for magma genesis within the upper mantle. Melting of the heterogeneous mantle consisting of peridotite and mafic (or pyroxenite/eclogite) rocks will yield voluminous and compositionally diverse magmas upon a melting process because of selective fusion of the mafic layers (e.g., Yasuda et al., 1994; Hauri, 1996; Takahashi et al., 1998). Melting experiments using heterogeneous mixtures of peridotite and MORB as a starting material, for example, have just started to examine this problem (Yaxley and Green, 1998; Kogiso et al., 1998). Mantle heterogeneity demonstrated by layered structure of peridotites and mafic (or pyroxenite/eclogite) rocks is conspicuous in many orogenic lherzolite massifs. We need to know how and when the inhomogeneous mantle materials have been produced. The Horoman Peridotite Complex, Hokkaido, northern Japan, has two specific features; one is the presence of symplectite, possibly of garnet origin, and the other is a symmetric layered structure characterized by an arrangement of cumulus peridotite and mafic rock in the middle of a series of residual peridotite with increasing melt component outward. The symmetrical layered structure repeats several times with intervals of several meters to a few hundred meters in the complex (Niida, 1984; Obata and Nagahara, 1987; Takahashi, 1992). Symplectite-bearing rocks in the Horoman complex are divided into three types based on petrography. The first, and the most abundant, is a kind of mantle restite, that is clinopyroxene-rich spinel lherzolite and plagioclase lherzolite. The second is a pyroxenite alternating with cumulus peridotites. The third is pyroxenites, which occur as thin layers in the mantle restite. Mineral assemblages and chemical compositions of the symplectites suggest that they were generally formed by the decompression reaction between pyrope-rich garnet and olivine. The presence of symplectite in cumulus peridotite and pyroxenite suggests the garnet was involved in the formation of cumulates at about 2 GPa or more. The mafic rocks in the Horoman complex have been divided into several types. One of these mafic layers, which is called Type II layer of Takazawa et al. (in press) or GB II of Niida (1984) and Shiotani and Niida (1984), restrictedly occurs in the cumulus peridotite which is located in the middle of residual peridotite with the symmetric layered structure. Some textural characteristics of the Type II mafic rocks are similar to those of the symplectite-bearing pyroxenites in the cumulus peridotite. The Type II mafic rocks have the same origin as symplectite-bearing pyroxenites, that is the subsolidus breakdown product of garnet-bearing pyroxenites of high-pressure origin to the gabbroic rock at lower-pressure conditions. On the other hand, their geochemical signatures indicated that the Type II mafic rocks were originally formed at lower-pressure conditions (Shiotani and Niida, 1997; Takazawa et al., in press). Textural characteristics of a corundum-bearing Type II mafic rock (Morishita and Kodera, 1998) show that corundum was not stable at the latest P-T conditions of the Horoman complex and require that it had experienced heating and/or decompression. A possible P-T history for the Type II mafic rock is as follows. (1) Type II mafic rock was formed as a cumulate at lower-pressure conditions from the melts responsible for the formation of the cumulus peridotite. (2) The protolith of Type II mafic rocks had been metamorphosed to garnet-bearing pyroxenite at high P-T conditions during compression due to subduction or convection within the mantle. (3) The complex ascended from the garnet stability field to the plagioclase peridotite stability filed as a diapir. The Type II mafic rocks as a member of the diapir were formed from garnet-bearing pyroxenite through symplectite-bearing rock due to breakdown of garnet and corundum at low pressures. The Type II mafic rocks have a complex P-T trajectory after it was formed as a member of the layered structure. We favor the possibility that the symmetrical layered structure in the Horoman complex have been repeated by deformation processes (Toramaru, 1997), not by the melting process along multiple parallel cracks (Takahashi, 1992). The melting process, however, had an important role in formation of a stratified lithological unit composed of cumulate rock, residual peridotite and primitive peridotite.
AN:  2219267

Record 14 of 393 in GEOBASE 1997/12-2001/08

TI:  Petrogenesis and evolution of the Dineibit El-Qulieb hyperaluminous leucogranite, Southeastern Desert, Egypt: Petrological and geochemical constraints.
AU:  El-Sayed-M.M.; El-Nisr-S.A.
SO:  Journal-of-African-Earth-Sciences. 1999; 28(3): 703-720
FTXT:  ScienceDirect (tm) http://www.sciencedirect.com/science?_ob=GatewayURL&_origin=SilverLinker&_urlversion=4&_method=citationSearch&_volkey=0899%2d5362%2328%23703%233&_version=1&md5=700daa1a9d4a7ecec269c44a5544b7de
AB:  The Dineibit El-Qulieb Leucogranite exhibits most features of I-type granitoids (calc-alkaline affinity, relatively high Na<inf>2</inf>O, moderate values of Rb, Ba, LREE, Rb/Sr and low Rb/Ba with the presence of magnetite and titanite as the main accessories). On the other hand, they possess hyperaluminous (molar A/CNK = 1.22-1.43) and high normative corundum (5%), which are in contrast to typical I-type granitoids. The REE patterns are characterised by fractionated LREE and relatively flat HREE with pronounced negative Eu anomalies. The investigated rocks have low K/Rb and high Zr/Y ratios reflecting a typical mature continental-arc environment. The absence of recrystallised phases and the undepleted and flat HREE of the Dineibit El-Qulieb Leucogranite pattern argue against its formation by partial melting of crustal materials. Based on the petrological and geochemical features, the Dineibit El-Qulieb Leucogranite can be generated by fractional crystallisation of mafic magma. The Qulieb leucogranites are characterised by LILE enrichment, normative corundum-rich, strongly peraluminous compositions and associated with miarolitic cavities and pegmatitic patches suggesting the role of the aqueous fluids released from the downgoing slab during subduction. The main fractionating phases were hornblende, biotite, plagioclase and alkali feldspars. Based on the modelling of major elements, the least differentiated adamellite sample requires 91% crystal fractionation, mainly of hornblende, plagioclase, K-feldspar and biotite, from dioritic liquid. On the other hand, the most felsic investigated adamellite sample can be generated by 29% fractional crystallisation of plagioclase, K-feldspar and biotite from the most basic adamellite sample.
AN:  2211751

Record 15 of 393 in GEOBASE 1997/12-2001/08

TI:  High-pressure and high-temperature metamorphism of the mafic and ultramafic Lac Espadon suite, Manicouagan Imbricate Zone, eastern Grenville Province, Quebec.
AU:  Cox-R.; Indares-A.
SO:  Canadian-Mineralogist. 1999; 37(2): 335-357
AB:  The Lac Espadon suite (LES) of the Manicouagan Imbricate Zone (Quebec) is comprised of layered mafic and ultramafic rocks, Labradorian in age (ca. 1650-1630 Ma) that were variably deformed and metamorphosed under high-pressure and high-temperature (high-PT) conditions during the Grenvillian Orogeny. Maximum P-T conditions of 780-930< degrees >C at 16-19 kbar (high-T eclogite facies) are recorded in massive coronitic troctolite and hornblendite from the western part of the LES. In these rocks, metamorphic coronas of orthopyroxene, clinopyroxene and garnet have grown at the expense of igneous olivine and plagioclase. Relict plagioclase contains inclusions of kyanite and corundum, and garnet coronas locally preserve growth zoning. Deformed margins of the mafic rocks have granoblastic hydrous assemblages that are interpreted to have equilibrated during exhumation at ca. 700< degrees >C at 10-12 kbar and then down to ca. 600< degrees >C at 5 kbar (amphibolite-facies conditions), suggesting a steep retrograde P-T path. Olivine gabbro from the eastern part of the LES records peak conditions of 775-870< degrees >C at 14.5-16.25 kbar. Granoblastic areas in the rock are partially hydrated and give conditions of 760-820< degrees >C at 12-14 kbar, suggesting a near-isothermal P-T trajectory. The P-T paths are compatible with structural evidence suggesting tectonic exhumation of these rocks by northwesterly thrusting, with extension on top of the pile. The high-PT conditions and steep decompression paths recorded by the LES are similar to those in several adjacent and nearby terranes, suggesting widespread tectonic exhumation of the lower crust in this area of the Grenville Province.
AN:  2210487

Record 16 of 393 in GEOBASE 1997/12-2001/08

TI:  The black skarns of Pine Canyon, Piute County, Utah.
AU:  Agrell-S.O.; Chinner-G.A.; Rowley-P.D.
SO:  Geological-Magazine. 1999; 136(4): 343-359
FTXT:  EBSCO Online http://www.ebsco.com/online/direct.asp?ArticleID=XERKHA3KG240LE3013YM
AB:  A small micromonzonite pluton intruding Miocene extrusives of the Marysvale volcanic field of southern Utah has undergone a sequence of explosive brecciation, syenite veining, rheomorphism, calcium metasomatism and zeolitization. Skarn-like occurrences of magnetite and Al-spinel-rich feldspathoidal rocks within the outcrop are of two main types: (1) an olivine-bearing variety with occasional REE-rich minerals (zirconolite) occurs as veins and seams in desilicated latite screens and xenoliths; (2) an aluminous, corundum- and hibonite-bearing variety with accessory zirconolite, perovskite and armalcolite occurs mainly as fillings to the micromonzonite breccias. The chemically disparate types are interpreted as having initiated as propylitic, and argillic/alunitic, alterations of latite country rock in the early hydrothermal system of the pluton. Subsequent intrusion of the micromonzonite to higher levels has incorporated these products into the igneous complex, in which they have experienced varying degrees of nephelinization, pyrometamorphism, rheomorphism and veining.
AN:  2207584

Record 17 of 393 in GEOBASE 1997/12-2001/08

TI:  Synthetic gedrite: A stable phase in the system MgO-Al<inf>2</inf>O<inf>3</inf>-SiO<inf>2</inf>-H<inf>2</inf>O (MASH) at 800 < degrees >C and 10 kbar water pressure, and the influence of FeNaCa impurities.
AU:  Fischer-H.; Schreyer-W.; Maresch-W.V.
SO:  Contributions-to-Mineralogy-and-Petrology. 1999; 136(1-2): 184-191
FTXT:  InformationQuest http://www.eiq.com/usr_login.html?sici=0010-7999%28000000%29136%3A1-2%3C184%3AX%3E2.0.CO%3B2-X
AB:  Seeded, solid-media piston-cylinder runs of unusually long duration up to 31 days indicate growth or persistence of synthetic gedrite of the composition []Mg<inf>6</inf>Al[AlSi<inf>7</inf>O<inf>2</inf><inf>2</inf>](OH)<inf>2</inf>(=6:1:7), prepared from the purest chemicals available, at 10 kbar water pressure and 800 < degrees >C. Conversely, breakdown was observed at 11 kbar and 850 < degrees >C to aluminous enstatite, Al<inf>2</inf>SiO<inf>5</inf>, and a melt of the composition MgO< middle-dot >Al<inf>2</inf>O<inf>3</inf>< middle-dot >8SiO<inf>2</inf>. Thus, pure gedrite free of iron, sodium, and calcium is likely to have only a small PT stability field in the MASH system, estimated as 10 ± 1 kbar, 800 ± 20 < degrees >C, even though metastable growth of gedrite can be observed over a larger PT range. A second starting material with the anhydrous composition 5MgO< middle-dot >2Al<inf>2</inf>O<inf>3</inf>< middle-dot >6SiO<inf>2</inf> also yielded gedrite of the composition 6:1:7, together with more aluminous phases such as kyanite, corundum or sapphirine, thus suggesting that the end-member gedrite defined as []Mg<inf>5</inf>Al<inf>2</inf>[Al<inf>2</inf>Si<inf>6</inf>O<inf>2</inf><inf>2</inf>](OH)<inf>2</inf>(=5:2:6) by the IMA Commission on New Minerals and Mineral Names probably does not exist. With the use of this second starting material, which contains FeNaCa impurities, growth of 6:1:7-gedrite was observed over a still wider PT-range. Seeded runs indicate that the true stability field of such slightly impure 6:1:7-gedrites may also be larger than that of the pure MASH phase and extend at least to 15 kbar, 800 < degrees >C. There is, thus, a remarkable stabilization effect on the orthoamphibole structure by impurities amounting only to a total of less than one weight percent of oxides in the starting material. The gedrites synthesized are structurally well ordered amphiboles nearly free of chain multiplicity faults, as revealed by HRTEM. The X-ray diffraction work on the gedrites synthesized yielded the smallest cell volume yet reported for this phase. The small stability field of the pure MASH gedrite is intersected by the upper pressure stability limit of hydrous cordierite for excess-H<inf>2</inf>O conditions, thus leading to complicated phase relations for both gedrite and cordierite involving the additional phases aluminous enstatite, talc, quartz, Al<inf>2</inf>SiO<inf>5</inf>, melt and perhaps boron-free kornerupine.
AN:  2205745

Record 18 of 393 in GEOBASE 1997/12-2001/08

TI:  Petrology of sapphirine-bearing and associated granulites from central Sri Lanka.
AU:  Kriegsman-L.M.; Schumacher-J.C.
SO:  Journal-of-Petrology. 1999; 40(8): 1211-1239
AB:  Calcium-poor, magnesian granulites from two localities in central Sri Lanka contain a rich variety of assemblages composed of combinations of sapphirine (Spr), garnet, orthopyroxene, sillimanite, cordierite or spinel. Quartz is present in some assemblages at the Hakurutale locality, and corundum and rare gedrite are present in some assemblages at the Munwatte locality. Rocks from both localities display diverse sets of inclusion and sequential reaction textures. The inclusions suggest that the earliest assemblage at Munwatte was orthopyroxene + spinel + corundum. Garnet growth followed by garnet breakdown occurred via the reactions orthopyroxene + corundum = garnet and garnet + corundum + spinel = sapphirine. This produced coarse-grained coronas of sapphirine around the corundum and spinel. The earliest assemblage at Hakurutale was orthopyroxene + sillimanite + sapphirine. Garnet growth occurred via the reactions orthopyroxene + sillimanite + sapphirine = garnet and orthopyroxene + sillimanite = garnet + quartz. Locally, garnet was partially destroyed by a variety of corona-forming continuous reactions. The most important are garnet = orthopyroxene + sillimanite + sapphirine and garnet + sillimanite = sapphirine + cordierite (both localities) and, at Hakurutale, garnet + quartz = orthopyroxene + sillimanite, garnet + sillimanite + quartz = cordierite and garnet + quartz = orthopyroxene + cordierite. In places, orthopyroxene + sillimanite + quartz reacted to form cordierite, and orthopyroxene + sillimanite reacted to form cordierite + sapphirine coronas. At Hakurutale, inclusion textures indicate that sapphirine was present in the earliest recorded assemblages (prograde), but also formed later as various corona-forming reactions occurred. On the basis of calculated orientations of model univariant curves and continuous reaction slopes for the observed phases, the P-T path is roughly a 'clockwise' (i.e. P(max) precedes T(max)) trajectory. The earlier, garnet-forming stage reflects heating possibly with a slight P increase. The final recorded leg suggests near-isothermal decompression starting at a peak P-T of about 9 kbar and 830< degrees >C and dropping to nearly 7.5 kbar at about 810< degrees >C. Sapphirine appears to have developed at several points along the P-T trajectory.
AN:  2202644

Record 19 of 393 in GEOBASE 1997/12-2001/08

TI:  Ultra-high temperature metamorphism of metapelitic granulites from Kondapalle, Eastern Ghats Belt: Implications for the Indo-Antarctic correlation.
AU:  Sengupta-P.; Sen-J.; Dasgupta-S.; Raith-M.; Bhui-U.K.; Ehl-J.
SO:  Journal-of-Petrology. 1999; 40(7): 1065-1087
AB:  A suite of quartz- and corundum-bearing metapelitic granulites, intruded by layered gabbronorite-pyroxenite-anorthosite at Kondapalle, Eastern Ghats Belt, preserves a multitude of reaction textures involving oxide and silicate minerals that attest to several prograde and retrograde reactions. In the quartz-bearing associations, the reactions are: (a) biolite + sillimanite + quartz &rarr; garnet + liquid; (b) garnet + sillimanite &rarr; spinel ( + magnetite) + quartz; (c) Fe<inf>2</inf>TiO<inf>4</inf> + O<inf>2</inf> &rarr; ferrian ilmenite + magnetite; (d) reversal of reaction (b); (e) Fe<inf>2</inf>O<inf>3</inf>-rich ilmetite + plagioclase + quartz &rarr; Fe<inf>2</inf>O<inf>3</inf>-poor ilmenite + garnet + O<inf>2</inf>. Reactions in the corundum-bearing associations are: (f) spinel + biotite + sillimanite &rarr; garnet + liquid; (g) biotite + sillimanite &rarr; garnet + Ti-rich spinel + corundum + liquid; (h) biotite + sillimanite &rarr; garnet + corundum + liquid; (i) Fe<inf>2</inf>TiO<inf>4</inf> + FeAl<inf>2</inf>O<inf>4</inf> + O<inf>2</inf> &rarr; ferrian ilmenite + Fe<inf>3</inf>O<inf>4</inf> + Al<inf>2</inf>O<inf>3</inf> (in ilmenite); (j) garnet + corundum &rarr; spinel + sillimanate. To examine the paragenetic evolution of the metapelitic granulites, a petrogenetic grid for the KFMASH system at high temperatures and pressures, involving quartz and corundum, was constructed. The sequence of inferred reactions documents an anticlockwise heating-cooling path. Reintegrated compositions of spinel (with &gt; 10 mol % Fe<inf>2</inf>TiO<inf>4</inf>) and feldspars indicate ultra-high temperature (UHT) of metamorphism (&gt; 1000&deg;C), comparable with the liquidus temperature of the enclosing magmatic rocks. Crystallization pressures inferred for the magmatic rocks and the pressure constraints imposed by the petrogenetic grid on the metapelite assemblages indicate that the emplacement of the igneous suite and the accompanying UHT metamorphism occurred in the lower crust (&gt; 8 kbar). Reported U-Pb cooling ages of monazite and allanite from a late pegmatite suggest the UHT metamorphism to be older than 1600 Ma. The deduced P-T history and the absence of Grenvillian high-grade metamorphism in the study area provide important constraints on the configuration of East Gondwana, in particular on the continuation of the Napier-Rayner terrane boundary into the Eastern Ghats Belt.
AN:  0434446

Record 20 of 393 in GEOBASE 1997/12-2001/08

TI:  Megacrysts and associated xenoliths: Evidence for migration of geochemically enriched melts in the upper mantle beneath Scotland.
AU:  Upton-B.G.J.; Hinton-R.W.; Aspen-P.; Finch-A.; Valley-J.W.
SO:  Journal-of-Petrology. 1999; 40(6): 935-956
AB:  Megacrysts, principally anorthoclase, Fe-rich biotite, clinopyroxene, magnetite, zircon and apatite, occur in alkali basaltic hosts at a number of Scottish localities. These minerals occur, not only as discrete, and composite megacrysts, but also as polycrystalline syenite (anorthoclasite) xenoliths. Composite xenoliths provide evidence that the anorthoclasites may occur as (pegmatitic) veins traversing pyroxenitic wall-rocks which may themselves be localized metasomatized peridotites within the shallow mantle. The anorthoclasites crystallized from highly trace element enriched melts which, in the case of the most geochemically extreme samples, were also peraluminous. Ion microprobe analyses show that the peraluminous (corundum-bearing) anorthoclasites comprise light rare earth element (LREE)-enriched alkali feldspars together with corundum and Nb-rich oxides (ilmenorutile, samarskite, yttro-niobate and columbite). The high contents of incompatible elements, together with oxygen isotope data, indicate crystallization of these syenitic facies from felsic melts, possibly originating through partial melting of metasomatized mantle lithologies. The aluminous character may be explained in terms of preferential loss of alkalis in fugitive carbonatitic fractions separated from the felsic melts.
AN:  0434134

Record 21 of 393 in GEOBASE 1997/12-2001/08

TI:  The petrology of mullite-bearing peraluminous xenoliths: Implications for contamination processes in basaltic magmas.
AU:  Preston-R.J.; Dempster-T.J.; Bell-B.R.; Rogers-G.
SO:  Journal-of-Petrology. 1999; 40(4): 549-573
AB:  A suite of high-level inclined sheets ranging in composition from basalt through to rhyolite is intruded into the Palaeogene lava field and underlying Moine Supergroup basement rocks around Loch Scridain, Isle of Mull, Scotland. Many of the sheets are highly xenolithic, containing a wide variety of crustal xenolith types derived from the Moine metasedimentary rocks, along with various gabbroic cumulate xenoliths. The most common xenolith types are almost pure quartzites and a variety of mullite-bearing aluminous buchites, many of the latter having thick crystalline selvages of plagioclase, corundum and aluminous spinel. The plagioclase is highly calcic (up to An<inf>8</inf><inf>7</inf>), and adjacent to the host basalt is commonly oscillatory zoned, implying crystallization from a melt. Trapped between plagioclase crystals are pockets of quenched, contaminated basic melt, which contain skeletal plagioclase and clinopyroxene, and preserve evidence of local mixing between the host basalt and the aluminous crustal melts. Sr and Nd isotope values of the buchite cores [e.g. (<sup>8</sup><sup>7</sup>Sr/<sup>8</sup><sup>6</sup>Sr)<inf>5</inf><inf>5</inf> = 0.7074-0.7115], plagioclase selvages [e.g. (<sup>8</sup><sup>7</sup>Sr/<sup>8</sup><sup>6</sup>Sr)<inf>5</inf><inf>5</inf> = 0.1737-0.7148], and associated trapped melts [e.g. (<sup>8</sup><sup>7</sup>Sr/<sup>8</sup><sup>6</sup>Sr)<inf>5</inf><inf>5</inf> = 0.7126-0.7128], imply a complex series of magma-xenolith interactions. The textural characteristics, mineral chemistry and isotope geochemistry of these rims suggest that they have crystallized from a hybrid liquid formed by the complex interaction of the aluminous liquids with basic magmas. Such interaction proceeded via liquid-liquid diffusion, physical mixing of melts and a variety of reactions between the crystallization products of the buchites and the basaltic liquids. These crustal xenoliths preserve a detailed record of mineral-melt reactions within a suite of basaltic sheets, dominated by both the production of granitic melts and the 'bulk' melting of Al-rich micaceous lithologies.
AN:  0414078

Record 22 of 393 in GEOBASE 1997/12-2001/08

TI:  Desilication veins in the Cadillac Mountain granite (Maine, USA): A record of reversals in the SiO<inf>2</inf> solubility of H<inf>2</inf>O-rich vapour released during subsolidus cooling.
AU:  Nichols-G.T.; Wiebe-R.A.
SO:  Journal-of-Metamorphic-Geology. 1998; 16(6): 795-808
AB:  Late-stage hydrous fluids, which evolved during the cooling of the Cadillac Mountain granite, Maine, USA, produced narrow veins that transect the pluton. The vein margins contain microstructures transitional between granite and the vein centre. They preserve the vestige shapes of original Na-rich alkali feldspar crystals that have been pseudomorphed by cordierite+quartz+K-rich alkali feldspar. Closer to the centres of the veins, the minerals change from an outer zone with cordierite, hercynitic-galaxite spinel, minor corundum, K-feldspar and plagioclase to an inner zone with remnant cordierite, hercynitic gahnite, strongly zoned almandine-spessartine garnet, chlorite and quartz. Three allochemical reactions are inferred to have occurred with the influx of hydrous fluids during the replacement process. Reaction (1) is Na-rich alkali feldspar+iron ions in solution=Fe-cordierite+quartz+K-feldspar+sodium ions in solution. Reactions (2) and (3) occurred during desilication. Reaction (2) is Fe-cordierite= hercynite+silica in solution, and reaction (3) is Fe-cordierite+water=corundum+iron hydroxide in solution+silicic acid in solution. Two independent techniques, experimental silica-solubility data and spinel-cordierite thermobarometry, constrain the conditions of vein formation to c. 1.0 kbar and both methods indicate that the progressive mineral reactions occurred during cooling of the hydrous fluids from c. 775&deg;to 400-340&deg;C. This cooling trend is consistent with the petrographic evidence, which demonstrates that reactions occurred before desilication, during desilication, and then diminished with a final phase of resilication. Although the veins are minor features of the Cadillac Mountain granite, they provide insight into the conditions that prevailed during cooling of the pluton, and similar features may be important for constraining the cooling history of shallow-level plutonic complexes elsewhere.
AN:  0398770

Record 23 of 393 in GEOBASE 1997/12-2001/08

TI:  An experimental investigation on the P-T stability of Mg-staurolite in the system MgO-Al<inf>2</inf>O<inf>3</inf>-SiO<inf>2</inf>-H<inf>2</inf>O.
AU:  Fockenberg-T.
SO:  Contributions-to-Mineralogy-and-Petrology. 1998; 130(2): 187-198
FTXT:  EBSCO Online http://www.ebsco.com/online/direct.asp?ArticleID=XNRXVPGLEEEQCUNYBEQB InformationQuest http://www.eiq.com/usr_login.html?sici=0010-7999%28000000%29130%3A2%3C187%3AX%3E2.0.CO%3B2-X
AB:  The pressure-temperature stability field of Mg-staurolite, ideally Mg<inf>4</inf>Al<inf>18</inf>Si<inf>8</inf>O<inf>46</inf>(OH)<inf>2</inf>, was bracketed for six possible breakdown reactions in the system MgO-AlAl<inf>2</inf>O<inf>3</inf>-SiO<inf>2</inf>-H<inf>2</inf>O (MASH). Mg-staurolite is stable at water pressures between 12 and 66 kbar and temperatures of 608-918 &deg;C, requiring linear geotherms between 3 and 18&deg;C/km. This phase occurs in rocks that were metamorphosed at high-pressure, low-temperature conditions, eg, in subducted crustal material, provided they are of appropriate chemical composition. Mg-staurolite is formed from the assemblage chlorite + kyanite + corundum at pressures &lt;24 kbar, whereas at pressures up to 27 kbar staurolite becomes stable by the breakdown of the assemblage Mg-chloritoid + kyanite + corundum. Beyond 27 kbar the reaction Mg-chloritoid + kyanite + diaspore = Mg-staurolite + vapour limits the staurolite field on its low-temperature side. The upper pressure limit of Mg-staurolite is marked by alternative assemblages containing pyrope + topaz-OH with either corundum or diaspore. At higher temperatures Mg-staurolite breaks down by complete dehydration to pyrope + kyanite + corundum and at pressures below 14 kbar to enstatite + kyanite + corundum. The reaction curve Mg-staurolite = talc + kyanite + corundum marks the low-pressure stability of staurolite at 12 kbar. Mg-staurolite does not coexist with quartz because alternative assemblages such as chlorite-kyanite, enstatite-kyanite, talc-kyanite, pyrope-kyanite, and MgMgAl-pumpellyite-kyanite are stable over the entire field of Mg-staurolite.
AN:  0374546

Record 24 of 393 in GEOBASE 1997/12-2001/08

TI:  Boron in granitic magmas: stability of tourmaline in equilibrium with biotite and cordierite.
AU:  Wolf-M.B.; London-D.
SO:  Contributions-to-Mineralogy-and-Petrology. 1997; 130(1): 12-30
FTXT:  EBSCO Online http://www.ebsco.com/online/direct.asp?ArticleID=5D95VH9F66UEL071W6WK InformationQuest http://www.eiq.com/usr_login.html?sici=0010-7999%28000000%29130%3A1%3C12%3AX%3E2.0.CO%3B2-X
AB:  Experiments at 750&deg;C, 200 MPa<inf>(H<inf>2</inf>O)</inf>, a<inf>(H<inf>2</inf>O)</inf> = 1, and f<inf>O<inf>2</inf></inf> &tilde; Ni-NiO established that the equilibrium among tourmaline, biotite, cordierite, and melt (&plusmn; spinel, aluminosilicate or corundum) occurs with &tilde;2 wt% B<inf>2</inf>O<inf>3</inf> in strongly peraluminous melt with an aluminosity, measured by the parameter ASI, of &gt;1.2. The experiments demonstrate the relationship of tourmaline stability to the activity product of the tourmaline components boron and aluminium, which are inversely related to one another. Tourmaline is unstable in metaluminous to mildly peraluminous melts (ASI &lt;1.2) at 750&deg;C regardless of their boron content. For a given aluminosity, addition of components such as F requires a greater boron content of melt at this equilibrium. The stability of tourmaline increases with decreasing temperatures below 750&deg;C. At the inception of melting, tourmaline breaks down incongruently to assemblages containing crystalline AFM silicates (biotite, cordierite, garnet, sillimanite), aluminates (spinel, corundum) and B-enriched but Fe-Mg-poor melt. Granitic melts are likely to be undersaturated in tourmaline from the start of their crystallization, and their initial boron contents will be limited by the abundance of tourmaline in their source rocks. Quartzofeldspathic (gneissic, metapelitic) rocks that reached conditions of the granulite facies and still contain (prograde) tourmaline are rare, and probably have never yielded a partial melt. Most leucogranitic magmas will initially crystallize biotite, cordierite or garnet, but not tourmaline. With crysallization, the Fe-Mg content of melt decreases, and the B<inf>2</inf>O<inf>3</inf> content increases until the tourmaline-biotite and/or tourmaline-cordierite (or garnet) equilibria are attained. The B<inf>2</inf>O<inf>3</inf> content of melt is buffered as long as these equilibria continue to operate, but low initial Fe-Mg contents of the magmas limit the quantity of boron that can be consumed by these reactions to &lt;1 wt% B<inf>2</inf>O<inf>3</inf>. Normally leucogranitic magmas contain insufficient Fe and Mg to conserve all boron as tourmaline and thus lose a large fraction of magmatic boron to wallrocks. Leucogranites and pegmatites with tourmaline as an early and only AFM silicate mineral probably contained &gt;2 wt% B<inf>2</inf>O<inf>3</inf> in their bulk magmas.
AN:  0373408

Record 25 of 393 in GEOBASE 1997/12-2001/08

TI:  Comparative petrology of Archaean anorthosites in amphibolite and granulite facies terranes, SW Greenland.
AU:  Owens-B.E.; Dymek-R.F.
SO:  Contributions-to-Mineralogy-and-Petrology. 1997; 128(4): 371-384
FTXT:  EBSCO Online http://www.ebsco.com/online/direct.asp?ArticleID=DHCKCQRNH53B1PHRKF4R InformationQuest http://www.eiq.com/usr_login.html?sici=0010-7999%28000000%29128%3A4%3C371%3AX%3E2.0.CO%3B2-X
AB:  We report new field and petrographic observations, and mineral-chemical data, on the amphibolite-facies Buksefjorden and granulite-facies Nordland anorthosites, which occur in different tectonostratigraphic terranes within the Archaean gneiss complex of SW Greenland. The Buksefjorden body [from the Akulleq (middle) terrane] is dominated by plagioclase and Ca-amphibole, but shows widespread effects of retrograde hydration (epidote, chlorite). Most plagioclase compositions are in the An<inf>60-82</inf> range, with the majority of samples showing average core compositions &tilde;An<inf>76</inf>, whereas rims or recrystallized margins are &tilde;An<inf>65</inf>. Most grains in the An<inf>70-82</inf> range display optically visible Huttenlocher intergrowths. Amphiboles at Buksefjorden are mainly magnesio-hornblende with X<inf>Mg</inf> ranging from 0.70 to 0.45. The Nordland anorthosite [from the Akia (northern) terrane] is also dominated by plagioclase and Ca-amphibole, but contains additional clinopyroxene (&tilde;Ca<inf>47</inf>Mg<inf>38</inf>Fe<inf>15</inf>) as well as minor orthopyroxene (&tilde;En<inf>68</inf>), spinel and corundum. Plagioclase at Nordland shows an equilibrated, equigranular texture, consistent with prolonged slow cooling from high temperatures. Despite this textural equilibration, plagioclase at Nordland shows a striking range of compositions from An<inf>28</inf> to An<inf>97</inf>, most of which is found in single thin sections. A distinctive feature is the presence of discrete anorthite (+ spinel &plusmn; corundum) domains in some samples. Although a number of explanations may apply, we consider these domains to result from prograde mass transfer reactions involving Ca-amphibole and plagioclase. Amphibole compositions at Nordland show similar X<inf>Mg</inf> to those at Buksefjorden, but are more aluminous, alkalic, titanian. This shift to more pargasitic compositions is consistent with the contrasts in metamorphic grade between the two anorthosite bodies. At Buksefjorden, there is no correlation between the amount of modal Ca-amphibole and plagioclase composition, which would be expected if amphibole was produced solely through metamorphism. Our results suggest, alternatively, that the primary igneous mineralogy of these rocks may have been plagioclase (&tilde;An<inf>76</inf>) + hornblende + pyroxene + magnetite. The primary mineralogy at Nordland is less certain, but it is noteworthy that no rocks contain anorthite of unambiguous igneous origin, in contrast to some other occurrences of Archaean anorthosites.
AN:  0370260

Record 26 of 393 in GEOBASE 1997/12-2001/08

TI:  Enclaves in the Rochovce granite intrusion as indicators of the temperature and origin of the magma.
AU:  Hrasko-L.; Kotov-A.B.; Salnikova-E.B.; Kovach-V.P.
SO:  Geologica-Carpathica. 1998; 49(2): 125-138
AB:  Two boreholes in the Mo-W-bearing porphyric Cretaceous granite, located near the village of Rochovce, Western Carpathians, reveal the existence of two types of enclaves: 1) micaceous enclaves (biotite-plagioclase gneisses without quartz, with highly calcitic plagioclases, and 2) mafic microgranular enclaves (MME), with predominantly dioritic composition. In the first type, corundum, Zn-hercynite and magnetite were produced due to the high temperature melting of biotite. These are considered to be restites. The melting reactions in biotite indicate that the granite magma temperatures exceeded 800&deg;C at the time of the enclave melting. The mafic microgranular enclaves represent portions of mafic magma incorporated in the granitic magma. Seven types of mineralogical-petrological indicators of magma mixing were found. The chemical and Sm/Nd isotopic characteristics of the host granite and MME show that chemicaland isotopic equilibration was achieved within the granite-MME system. The initial &epsi;Nd value in granite (-3.0) indicates that some mafic magmatic material was added to the magma chamber. The apparent crustal residence age (T<inf>DM</inf> = 1100 Ma) indicates an old, Precambrian history of the crustal source material. Thus, the Rochovce magma was derived from a crustal source, with addition of more mafic (probably mantle-derived) magma.
AN:  0370255

Record 27 of 393 in GEOBASE 1997/12-2001/08

TI:  Peraluminous sapphirine formed during retrogression of a kyanite-bearing ecologite from Pays de Leon, Armorican Massif, France.
AU:  Godard-G.; Mabit-J.-L.
SO:  Lithos. 1998; 43(1): 15-29
FTXT:  ScienceDirect (tm) http://www.sciencedirect.com/science?_ob=GatewayURL&_origin=SilverLinker&_urlversion=4&_method=citationSearch&_volkey=0024%2d4937%2343%2315%231&_version=1&md5=0473d48eda15da34de926884e99816ab
AB:  In a quartz-free eclogite from Pays de Leon (Armorican Massif, France) kyanite has bene replaced by a symplectite of plagioclase, corundum, spinel and sapphirine. The sapphirine is amongst the most aluminous yet reported in the literature. One analysis (Mg<inf>1.38</inf>Fe<sup>2+</sup><inf>0.17</inf>Fe<sup>3+</sup><inf>0.05</inf>Cr<inf>0.01</inf>Al<sup>VI</sup><inf>2.37</inf>Al<sup>IV</sup><inf>2 .43</inf>Si<inf>0.57</inf>O<inf>10</inf>) shows the highest degree of Tschermak's substitution (Si<inf>-1</inf>Mg<inf>-1</inf>Al<sup>IV</sup>Al<sup>VI</sup>) yet reported for saphhirine. Omphacite has been completely transformed into clinopyroxene + plagioclase symplectite. A quantification of material transfer indicates that kyanite and omphacite breakdowns were coupled. The kyanite and omphacite pseudomorphs exchanged components during their formation but the two pseudomorphs together behave as a more-or-less closed system. The kyanite symplectitisation is the source of the silica required for the omphascite breakdown (ie, jadeite<inf>ss</inf>+SiO<inf>2</inf>&rarr;albite<inf>ss</inf>). The kyanite and omphacite pseudomorphs display all the characteristics of a metasomatic system at a microscopic scale (zonation, diffusion fronts, etc). These features are explained in terms of relative mobility of the chemical components. The kyanite and omphacite pseudomorphs give information about the P-T path of the Leon eclogites during retrograde metamorphism. The appearance of sapphirine after kyanite is attributed to a low-pressure and high-temperature evolution from eclogite-facies to granulite-faies conditions.
AN:  0370092

Record 28 of 393 in GEOBASE 1997/12-2001/08

TI:  Pseudosinhalite', a new hydrous MgAl-borate: synthesis, phase characterization, crystal structure, and PT-stability.
AU:  Daniels-P.; Krosse-S.; Werding-G.; Schreyer-W.
SO:  Contributions-to-Mineralogy-and-Petrology. 1997; 128(2-3): 261-271
FTXT:  InformationQuest http://www.eiq.com/usr_login.html?sici=0010-7999%28000000%29128%3A2-3%3C261%3AX%3E2.0.CO%3B2-X
AB:  The new synthetic phase Mg<inf>2</inf>Al<inf>3</inf>O[BO<inf>4</inf>]<inf>2</inf>(OH) provisionally named 'pseudosinhalite' is optically, chemically, and structurally similar to the mineral sinhalite, MgAl[BO<inf>4</inf>], isostructural with forsterite. It grows hydrothermally from appropriate bulk compositions in the range 4-40 kbar at temperatures that increase with pressure (&tilde;650 &rarr; 900 &deg;C), and it breaks down at higher temperatures to sinhalite + corundum + H<inf>2</inf>O. At P&ge; 20 kbar single-phase products of euhedral twinned crystals could often be obtained. Pseudosinhalite is monoclinic with a = 7.455 (1) <a><ac>A</ac><ac>&ring;</ac></a>, b = 4.330 (1) <a><ac>A</ac><ac>&ring;</ac></a>, c = 9.825 (2) <a><ac>A</ac><ac>&ring;</ac></a>, &beta; = 110.68 (1)&deg;, and space group P2<inf>1</inf>/C. Crystal structure analysis reveals that pseudosinhalite is also based on hexagonal close packing (hcp) of oxygen atoms with Mg and Al in octaedral and B in tetradral coordination. In pseudosinhalite the winged octahedral chains in the plane of hcp are not straight as in sinhalite but have a zigzag, 3-repeat period (Dreierkette), and only 1/10 instead of 1/8 of all tetrahedral sites are filled by boron. Hydrogen is located at a split position between two oxygen atoms 05-05, which are only 2550 <a><ac>A</ac><ac>&ring;</ac></a> apart and thus generate strong hydrogen bonding. This may be responsible for the absence of an hydroxyl absorption band between 2800 cm<sup>-1</sup> and 3500 cm<sup>-1</sup> in the powder IR spectrum. The equilibrium breakdown curve of pseudosinhalite to form sinhalite, corundum, and water was determined by bracketing experiments to pass through 10 kbar, 745&deg;C and 35 kbar, 950 &deg;C, giving a slope of about 8 &deg;C?kbar, similar to dehydration curves of some silicates at high pressure. In nature pseudosinhalite could have been misidentified as sinhalite. A possible appearance, like sinhalite in boron-rich skarns, would require more aluminous bulk compositions than for sinhalite at relatively low temperatures. However, pseudosinhalite might also form as a hydrous alteration product of sinhalite at low temperatures, perhaps in association with szaibelyite, MgBO<inf>2</inf>(OH).
AN:  0370014

Record 29 of 393 in GEOBASE 1997/12-2001/08

TI:  Textures of diffusion-controlled reaction in contact-metamorphosed Mg-rich granulite, Kokchetav area, Kazakhstan.
AU:  Ashworth-J.R.; Reverdatto-V.V.; Kolobov-V.Yu; Lepetyukha-V.V.; Sheplev-V.S.; Bryxina-N.A.
SO:  Mineralogical-Magazine. 1998; 62(2): 213-224
AB:  In a granulite from the Kokchetav massif, a complex mineral assemblage and intricate textures have resulted from a combination of unusual rock composition and two-stage metamorphic history. The second, contact metamorphism produced mainly cordierite and anthophyllite, reflecting a bulk composition attributed to pre-metamorphic alteration of basic igneous rock. From the first, high-pressure metamorphism, garnet relics persist while another mineral has been completely pseudomorphed. The garnet is partly replaced by a symplectite of three minerals: orthopyroxene vermicules in a coarser intergrowth of cordierite and calcic plagioclase. Despite variable proportions of cordierite and plagioclase, the Al:Si ratio of the symplectite is almost constant, because the proportion of orthopyroxene is smaller where the dominant aluminous mineral is cordierite (Al:Si &sime; 0.8) than where the even more aluminous plagioclase (Al:Si &sime; 0.89) is prominent. The bulk Al:Si ratio of this symplectite, approximately 0.69, is very close to that of reactant garnet (0.66), indicating that Al and Si have been retained almost completely during the local reaction, while other elements were more mobile. In the pseudomorphs, aluminous cores (with Al:Si ratios 1.61-1.93) indicate that the mineral which has been completely replaced was probably kyanite. These cores comprise plagioclase, zoisite, corundum and spinel, and are surrounded by layers of plagioclase and cordierite. Fe, Mg, and Ca have diffused to the core, through layers with low bulk concentrations of these elements, probably by grain-boundary diffusion in the solid state.
AN:  0359974

Record 30 of 393 in GEOBASE 1997/12-2001/08

TI:  A corundum-quartz assemblage from the Eastern Ghats Granulite Belt, India: evidence for high P-T metamorphism?
AU:  Shaw-R.K.; Arima-M.
SO:  Journal-of-Metamorphic-Geology. 1998; 16(2): 189-196
AB:  Corundum+quartz-bearing assemblages occur in small lenses in granulite facies metapelites in Rayagada, north-central part of the Eastern Ghats Granulite Belt, India. Corundum porphyroblasts and quartz coexist with porphyroblastic almandine-rich garnet, hercynite spinel, ilmenite and magnetite. Corundum and quartz are separated by sillimanite or a composite corona consisting of sillimanite and garnet, whereas corundum shows sharp grain boundaries with spinel, ilmenite and magnetite. Porphyroblastic corundum contains prismatic sillimanite inclusions in which irregularly shaped quartz is enclosed. Two distinct reactions are inferred from the textural features: corundum+quartz=sillimanite and spinel+quartz=garnet+sillimanite. From the petrographical features, we infer that corundum-quartz-garnet-spinel was the peak metamorphic assemblage. Although large uncertainties exist regarding the positions of the respective reactions in P-T space, from several published experimental results and theoretical calculations a peak metamorphic condition of 12 kbar and 1100&deg;C is estimated as the lower stability limit of the corundum-quartz assemblage. Decompression from the peak P-T condition to c. 9 kbar, 950&deg;C is inferred.
AN:  0348252

Record 31 of 393 in GEOBASE 1997/12-2001/08

TI:  Liquidus phase relations in the CaO-MgO-Al<inf>2</inf>O<inf>3</inf>-SiO<inf>2</inf> system at 3.0 GPa: the aluminous pyroxene thermal divide and high-pressure fractionation of picritic and komatiitic magmas.
AU:  Milholland-C.S.; Presnall-D.C.
SO:  Journal-of-Petrology. 1998; 39(1): 3-27
AB:  We present liquidus phase equilibrium data at 3.0 GPa for the model tholeiitic basalt tetrahedron, diopside-anorthite-forsterite-quartz, in the CaO-MgO-Al<inf>2</inf>O<inf>3</inf>-SiO<inf>2</inf> system. This pressure coincides with the invariant point (1568&deg;C) on the simplified model lherzolite solidus that marks the transition between spinel lherzolite and garnet lherzolite (fo + en + di + sp + gt + liq). The composition of the liquid at the invariant point (46.4 An, 16.0 Di, 33.5 Fo, 4.2 Qz, wt%) is a model olivine-rich basalt that lies slightly (0.2% excess fo) to the SiO<inf>2</inf>-poor side of the aluminous pyroxene plane, MgSiO<inf>3</inf>-CaSiO<inf>3</inf>-Al<inf>2</inf>O<inf>3</inf>. A large garnet primary phase volume is bordered by primary phase volumes for forsterite, spinel, sapphirine, corundum, enstatite, diopside, quartz, and kyanite. The observed absence of enstatite at the solidus of lherzolite at pressures above &tilde;3.3 GPa is readily understood from the phase relations in this system. During melting at these high pressures, enstatite first forms at a temperature somewhat above the solidus and then dissolves before complete melting. As pressure increases above 3.0 GPa, the aluminous pyroxene plane, MgSiO<inf>3</inf>-CaSiO<inf>3</inf>-Al<inf>2</inf>O<inf>3</inf>, becomes increasingly effective as a thermal divide that causes picritic and komatiitic melts lying on the silica-poor side of the plane to fractionate toward alkalic picritic compositions. However, if the rate of ascent of these melts is sufficiently rapid, expansion of the olivine primary phase volume as pressure decreases produces a fractionation trend dominated by olivine crystallization and the thermal divide is ignored.
AN:  0339553

Record 32 of 393 in GEOBASE 1997/12-2001/08

TI:  Structure and development of the lower crust and upper mantle of southwestern Japan: evidence from petrology of deep-seated xenoliths.
AU:  Nozaka-T.
SO:  Island-Arc. 1997; 6(4): 404-420
AB:  Basic and ultrabasic xenoliths included in Cenozoic alkali basalts from the Kibi and Sera plateaus, Southwest Japan, can be classififed into five groups on the basis of mineral association and texture. Their equilibration P-T conditions estimated from paragenesis and mineral chemistry indicate that the dominant rock type from the lower crust to upper mantle changes with increasing depth as follows: (i) pyroxene granulite (Group V) and metasediments; (ii) garnet gabbro (Group III) and corundum anorthosite (Group IV); (iii) spinel pyroxenite (Group II); and (iv) spinel ssperidotite and pyroxenite (Group I). Groups II and III show a lower degree of recrystallization than Groups I and V, and have similarities in composition and mineral chemistry to host basalts. Based on these facts along with the P-T conditions of equilibration, Groups II and III are interpreted as formed from basaltic magma that intruded beneath the crust-mantle boundary at an early stage of the magmatism of the alkali basalts, where the lower crust and uppermost mantle had consisted of Group V and metasediments, and Group I, respectively. It follows that the crust has grown downward due to underplating of basaltic magma beneath the bottom of pre-existing crust. Group IV has commonly the same mineral assemblage, corundum + calcic plagioclase + aluminous spinel, and shows locally, nearby kyanite crystals, almost the same texture as fine-grained aggregates in a quartzite xenolith. The aggregates appear to have been formed by reaction between kyanite and host basalt, and accordingly Group IV is interpreted as formed by reaction between metasediments and basaltic magma at the time of the underplating. The Kibi, Sera and Tsuyama areas are dsitinguished from the areas nearby the Sea of Japan by the occurrence of the garnet gabbro and corundum anorthosite xenoliths, by the absence of the assocation of olivine + plagioclase in basic and ultrabasic xenoliths, and by the lower temperature of equilibration of basic xenoliths. From these facts it is stressed that in genral the crust becomes thinner and geothermal gradient becomes higher towards the back-arc side. Such a regional variation in crustal structure must reflect the tectonic situation of Southwest Japan at the time of the magmatism of the alkali basalts, namely rifting and shallow-level magmatism at the back-arc side.
AN:  0334762

Record 33 of 393 in GEOBASE 1997/12-2001/08

TI:  Sapphirine-bearing granulites and related high-temperature metamorphic rocks from the Higo metamorphic terrane, west-central Kyushu, Japan.
AU:  Osanai-Y.; Hamamoto-T.; Maishima-O.; Kagami-H.
SO:  Journal-of-Metamorphic-Geology. 1998; 16(1): 53-66
AB:  The Higo metamorphic unit in west-central Kyushu island, southwest Japan is an imbricated crustal section in which a sequence of units with increasing metamorphic grade from high (northern part) to low (southern part) structural levels is exposed. The basal part of the metamorphic sequence representing an original depth of 23-24 km consists mainly of garnet-cordierite-biotite gneiss, garnet, orthopyroxene gneiss, orthopyroxene-bearing amphibolite and orthopyroxene-bearing S-type tonalite. These metamorphic rocks underwent high amphibolite-facies up to granulite facies metamorphism with peak P-T conditions of 720 MPa, 870&deg;C. In addition sapphirine-bearing granulites and related high-temperature metamorphic rocks also occur as tectonic blocks in a metamorphosed peridotite intrusion. The sapphirine-bearing granulites and their related high-temperature metamorphic rocks can be subdivided into five types of mineral assemblages reflecting their bulk chemical compositions as follows: (1) sapphirine-corundum-spinel-cordierite (2) cordundum-spinel-cordierite (3) garnet-cordundum-spinel-cordierite (4) garnet-spinel-gedrite-corundum, and (5) orthopyroexene-spinel-gedrite. These metamorphic rocks are characterized by unusually high Al<inf>2</inf>O<inf>3</inf> and low SiO<inf>2</inf> contents, which could represent a restitic nature remaining after partial melting of pelitic granulite under the ultra high-temperature contact metamorphism at the peak metamorphic event of the Higo metamorphic unit. The metamorphic conditions are estimated to be about 800 MPa and above 950&deg;C which took place at about 250 Ma as a result of the thermal effect of the regional gabroic rock intrusions.
AN:  0329987

Record 34 of 393 in GEOBASE 1997/12-2001/08

TI:  Stability of phlogopite in granitic melts, an experimental investigation.
AU:  Grochau-B.; Johannes-W.
SO:  Contributions-to-Mineralogy-and-Petrology. 1997; 126(3): 315-330
AB:  Water-saturated and water-undersaturated experiments (aH<inf>2</inf>O = 1.0 and 0.5) were performed in the temperature range 780-1040&deg;C at 2 and 5 kbar in order to determine the upper thermal stability of phlogopite in granitic melts. Starting compositions were: (A) subaluminous mixtures of 20 wt% synthetic phlogopite and 80 wt% synthetic anhydrous haplogranitic glass; (B) peraluminous mixtures (normative corundum = 4%) of 20 wt% synthetic phlogopite and 80 wt% synthetic anhydrous peraluminous haplogranitic glass. The molar quartz: albite: orthoclase ratio of the glasses of the 2 kbar runs was 35:39:26 and that of the 5 kbar runs 30:42:28. In the subaluminous system, phlogopite is stable up to 820&deg;C at aH<inf>2</inf>O = 1.0 and up to 780&deg;C at aH<inf>2</inf>O = 0.5. At higher temperatures, it is replaced by enstatite. In the peraluminous system phlogopite has a remarkably higher thermal stability (up to 1000&deg;C at 5 kbar and aH<inf>2</inf>O = 1.0) and there is a temperature interval of 80&deg;C at aH<inf>2</inf>O = 1.0, and 90-100&deg;C at aH<inf>2</inf>O = 0.5 between the first appearance of enstatite and the disappearance of phlogopite. In the peraluminous system, phlogopite is a solid solution (ss) of phlogopite, muscovite, talc and eastonite components. The crystalline product of the phlogopite<inf>ss</inf> breakdown reaction is an aluminous enstatite. The MgO-content of the melt depends on the normative corundum content of the starting material and the run temperature. It is independent of pressure. In the subaluminous system, the MgO-content ranges between 0.05 and 0.3 wt% in the temperature initerval 780-880&deg;C at both investigated water activities. The MgO-content of the peraluminous melts at aH<inf>2</inf>O = 1.0 ranges between 0.4 and 1.7 wt% and at aH<inf>2</inf>O = 0.5 between 0.2 and 1.4 wt% in the temperature range 780-980&deg;C.
AN:  0280957

Record 35 of 393 in GEOBASE 1997/12-2001/08

TI:  Desilicated pegmatites with dravite and corundum from the Ihtiman Sredna Gora Mt.
AU:  Petrussenko-S.; Arnaudov-V.
SO:  Geokhimiia-Mineralogiia-i-Petrologiia. 1996; 31(-): 65-77
AB:  A meta-ultrabasic body (75&times;75 m), occurring in biotite gneisses in the Stipon locality 3 km NE from the town of Ihtiman, hosts lenses of desilicated pegmatide up to 1.5&times;0.3 m in size. The pegmatite has a zonal structure; blocky white or grey-blue plagioclase (An<inf>42-68</inf>) with an abundant dravite mineralization in the central parts of lenses - vermiculite zone developed after primary phlogopite - actinolite zone - chlorite zone - talc zone. In addition to dravite, which forms radial-fibrous spherulites up to 1.5 cm in diameter and dendritic aggregates as well as less common single crystals (3-4 mm) of brown or zonal colour (brown core, blue rim), plagioclase includes also crystals of corundum of zonal colouration (blue core, pink rim), zoisite, clinozoisite, prehnite, sericite, fine flakes of graphite and rare small-grained (3-4 mm) quartz. A comparison between the mineral and chemical compositions of the gneisses, the pegmatites in them and the desilicated pegmatites at Stipon has made it possible to suggest a common source of the B and Al-rich vein rocks.
AN:  0263907

Record 36 of 393 in GEOBASE 1/90-11/97

TI:  Some aspects of petrology of the granites of the western Himalaya.
AU:  Sharma,-T.R.; Sharma,-K.R.
SO:  Journal,-Geological-Society-of-India. 1996. 48/1, 49-55.
AB:  Several granite plutons occur in the Great and Lesser Himalaya in Ladakh, Jammu and Kashmir. These granites assume batholithic to sub-batholithic dimensions and are composed of quartz, orthoclase, microcline, plagioclase, muscovite, biotite, hornblende and tourmaline besides epidote, apatite, rutile, zircon, magnetite, ilmenite and sphene as accessories. These granites are peraluminous as the molar proportions of Al"SUB 2" O"SUB 3" is greater than the molar proportions of (K"SUB 2" O+Na"SUB 2" O+CaO) . High molar Al"SUB 2" O"SUB 3" /(K"SUB 2" O+Na"SUB 2" O+CaO) ratios and normative corundum are indicative of the generation of these granites due to partial fusion of crustal materials.
AN:  (1223958); 97K-99999

Record 37 of 393 in GEOBASE 1/90-11/97

TI:  Petrology and geochemistry of anorthosite, Jiwan Singh Ki Beri, Barmer District, Rajasthan.
AU:  Chawade,-M.P.; Chandrasekaran,-V.
SO:  Journal,-Geological-Society-of-India. 1996. 47/6, 747-750.
AB:  Anorthosite occurs as a discontinuous ENE-WSW trending lensoidal discordant body within biotite granite and gneisses of pre-Malani age and lies to the SSW of the intersection of the Jaisalmer- Barwani and Lathi-Rajkot lineaments. It is a coarse-grained greenish grey rock with no banding or mineral lineation. It comprises of 92% plagioclase (An 70-78) and 7% hornblende. It is characterised by low SiO"SUB 2" , K"SUB 2" O, Ba and Rb and high Sr and has normative olivine, nepheline and corundum.
AN:  (1212198); 97K-99999

Record 38 of 393 in GEOBASE 1/90-11/97

TI:  Geology and genesis of peraluminous granites in east Tianshan Upper Paleozoic island arc belt.
AU:  Gu-Lianxing; Yang-Hao; Yan-Zhengfu; Liao-Jingjuan; Wang-Jinzhu
SO:  Chinese-Journal-of-Geochemistry-(English-Edition). 1996. 15/1, 33-43.
AB:  A peraluminous granite belt occurs along the connecting zone between the Turpan-Hami Precambrian block and the Upper Paleozoic island arc belt. Muscovite granite and two-mica granite are the essential lithological components of that belt. All the potassium feldspars in these granites are microcline. Heavy minerals are dominated by magnetite. SiO"SUB 2" contents of these granites are greater than 73% with most of the A/NKC values greater than 1.1, normative corundum values greater than 1. Plots of CIPW norms in the (Al-K-Na)-Ca-(Fe"SUP 2+" +Mg) diagram are mostly situated in the plagioclase-cordierite-muscovite region. The rocks are characterized by very low contents of minor elements and SIGMA REE with strong Eu depletion, delta "SUP 18" O values between 6.6per mille and 7.0per mille , Rb-Sr isochron age of 260.2 plus or minus 6.2 Ma and an initial "SUP 87" Sr/"SUP 86" Sr ratio of 0.7052. These granites might have been produced by partial melting of moderately acidic volcanites and low-maturity sediments in the basement sequences and could be genetically connected with the southward A-type subduction of the Turpan-Hami block following the closure of the Middle Carboniferous back-arc basin.
AN:  (1202637); 97K-99999

Record 39 of 393 in GEOBASE 1/90-11/97

TI:  An unusual ruby-sapphire-sapphirine-spinel assemblage from the Tertiary Barrington volcanic province, New South Wales, Australia.
AU:  Sutherland,-F.L.; Coenraads,-R.R.
SO:  Mineralogical-Magazine. 1996. 60/4, 623-638.
AB:  Ruby-sapphire-sapphirine-spinel forms small, corroded, crystalline aggregates in corundum bearing alluvials shed from the Tertiary Barrington basalt shield volcano. The aggregates give new insights into the ruby-sapphire source rocks. Potential origins include metamorphic recrystallization of aluminous material (below 1460degrees C) or high temperature-high pressure crystallization reactions related to lamprophyric or basaltic magmas (up to 1300degrees C and 20 kbar). Sapphirine-spinel thermometry suggests final crystallization temperatures for the aggregates around 780 to 940degrees C and reaction with host magmas at over 1000degrees C.
AN:  (1203178); 97K-99999

Record 40 of 393 in GEOBASE 1/90-11/97

TI:  Bearthite, Ca "SUB 2" Al(PO "SUB 4" ) "SUB 2" OH: stability, thermodynamic properties and phase relations.
AU:  Brunet,-F.; Chopin,-C.
SO:  Contributions-to-Mineralogy-and-Petrology. 1995. 121(3), pp 258-266.
AB:  The new phosphate bearthite, Ca "SUB 2" Al(PO "SUB 4" ) "SUB 2" OH, found in high-pressure metamorphic rocks, has been synthesized from a stoichiometric mixture of gamma -Al "SUB 2" O "SUB 3" and CaHPO "SUB 4" .2H "SUB 2" O between 4 kbar water pressure, 485 degrees C and 24.5 kbar, 800 degrees C. Its upper temperature stability limit, bearthite left and right arrows hydroxyapatite + corundum + berlinite + H "SUB 2" O, has been tightly reversed between 485 degrees C, 1 kbar, and 850 degrees C, 10 kbar. The following thermodynamic parameters were extracted for bearthite: H "SUP o" "SUB f 298" = -4327.25 kJ/mol and S "SUP o" "SUB 298" = 214.5 J/mol. K, using a new DELTA "SUB r" Cp approximation for dehydration reactions. Additional experiments on the reaction trolleite left and right arrows berlinite + corundum + H "SUB 2" O yield new thermodynamic data for trolleite. Phase relations were derived in the CaO-P "SUB 2" O "SUB 5" -Al "SUB 2" O "SUB 3" -H "SUB 2" O system considering the phosphates bearthite, trolleite, berlinite, augelite, and hydroxyapatite. -from Authors
AN:  (1189565); 96K-13255

Record 41 of 393 in GEOBASE 1/90-11/97

TI:  High-grade metamorphism and retrogression of Moldanubian granulites, Austria.
AU:  Petrakakis,-K.; Jawecki,-C.
SO:  European-Journal-of-Mineralogy. 1995. 7(5), pp 1183-1203.
AB:  Charnockitic granulites from the Dunkelsteiner Wald, Moldanubian zone in Austria, bear the assemblage Grt "SUP 1" + Opx + Bt + Kfs + Plg + Qz + Rt + Ilm. Textural and compositional relations suggest a near- equilibrium state among these minerals, thus allowing the application of thermobarometry. Estimated conditions for the latest high- temperature overprint are 770 degrees C, 10.7, kbar and a H "SUB 2" O = 0.1. Textures and phase relations suggest that zoisite and margarite were formed during the early stages of retrogression as the PT -path entered the stability field of the assemblage zoisite + margarite. Break- down of garnet and inclusions of corundum and plagioclase therein was initiated by infiltration fluids. Late stage of retrogression are documented by the diasporization of corundum. The studied rocks show a clockwise PT -path characterized by: 1), isothermal decompression during and after attainment of peak metamorphic conditions, 2), nearly isobaric cooling in the range 500-600 degrees C and 5-6 kbar and 3), further decompression that may be related to thrusting of Moldanubia over Moravia. -from Authors
AN:  (1141424); 96K-01618

Record 42 of 393 in GEOBASE 1/90-11/97

TI:  Experimental study of chloritoid stability at high pressure and various f O "SUB 2" conditions.
AU:  Vidal,-O.; Theye,-T.; Chopin,-C.
SO:  Contributions-to-Mineralogy-and-Petrology. 1994. 118(3), pp 256-270.
AB:  The reaction chloritoid (ctd) = almandine (alm) + diaspore + H "SUB 2" O (CAD) has been reversed using Fe "SUP 3+" -free synthetic chloritoid and almandine, under f O "SUB 2" conditions of the solid oxygen buffer Fe/FeO (CADWI), and using partially oxidized synthetic minerals under f O "SUB 2" conditions of the solid oxygen buffer Ni/NiO (CADNNO) . Experiments have been conducted between 550 and 700 degrees C, 25 and 45 kbar. The equilibrium pressure and temperature conditions are strongly dependent on the f O "SUB 2" conditions. This can be explained by a decrease in a H "SUB 2" O for experiments conducted on the Fe/FeO buffer, and a decrease in a ctd and a alm for experiments conducted on the Ni/NiO buffer. The H "SUB 2" O activity has been calculated using the MRK equation of state, and the values obtained checked against the shift of the equilibrium diaspore = corundum + H "SUB 2" O bracketed on the Fe/FeO buffer and under unbuffered f O "SUB 2" conditions. -from Authors
AN:  (1117695); 95K-11573

Record 43 of 393 in GEOBASE 1/90-11/97

TI:  Sapphirine-quartz and sapphirine-corundum assemblages in metamorphic rocks associated with the Semail Ophiolite (United Arab Emirates).
AU:  Gnos,-E.; Kurz,-D.
SO:  Contributions-to-Mineralogy-and-Petrology. 1994. 116(4), pp 398-410.
AB:  Granulite facies metasedimentary and metavolcanic rocks occur imbricated with the Cretaceous Semail Ophiolite in the United Arab Emirates and Oman. Peak metamorphic assemblages in highly oxidized lithologies of these rocks include sapphirine (7:9:3)-hercynitic spinel-magnetite-ilmeno-hematite-plagioclase-enstatite-quartz and sapphirine (2:2:1)-corundum-ilmeno-hematite-phlogopite-plagioclase. The observed mineral assemblages in quartzitic rocks are an example of overlapping stability of sapphirine-quartz and spinel-quartz and are therefore not diagnostic for high pressures. The common association of sapphirine and spinel with magnetite and ilmeno-hematite in quartzitic rocks suggests that sapphirine was formed by a reaction including spinel, hematite and quartz on the educt side. -from Authors
AN:  (1062108); 94K-12941

Record 44 of 393 in GEOBASE 1/90-11/97

TI:  Sapphirine and Ti-clinohumite in ultra-high-pressure garnet- pyroxenite and eclogite from Dabie Shan, China.
AU:  Okay,-A.-I.
SO:  Contributions-to-Mineralogy-and-Petrology. 1994. 116(1-2), pp 145-155.
AB:  Sapphirine occurs as inclusions along with clinochlore, enstatite, talc, corundum, gedrite, hornblende and phlogopite in millimetre- size garnets from the orthopyroxenites in a 50-m-thick mafic ultramafic lens in Dabie Shan in China. The lens, enclosed by felsic gneiss, is made up of metre-scale intercalation of garnet-orthopyroxenite, garnet-clinopyroxenite, eclogite and gneiss. The equilibrium conditions of the matrix minerals were 740 +/- 50 degrees C temperature and over 40 kbar pressure. Pressures of over 28 kbar are also indicated by inclusions of quartz pseudomorphs after coesite in garnet from the eclogites. Phase relations among the inclusion minerals, on the other hand, indicate similar temperatures of 730 +/- 30 degrees C but much lower pressures of 4 +/- 2 kbar. The mafic-ultramafic lens was therefore not a direct mantle fragment but was probably a low-pressure cumulate in the upper crust. -from Author
AN:  (1048996); 94K-11681

Record 45 of 393 in GEOBASE 1/90-11/97

TI:  Pd-oxide equilibration: a new experimental method for the direct determination of oxide activities in melts and minerals.
AU:  Chamberlin,-L.; Beckett,-J.-R.; Stolper,-E.
SO:  Contributions-to-Mineralogy-and-Petrology. 1994. 116(1-2), pp 169-181.
AB:  A new technique has been developed for the experimental determination of the activities of oxide components in melts and minerals using the equilibrium between Pd alloy, oxygen, and the oxide component in the sample of interest. If a melt or mineral sample is equilibrated with Pd metal at fixed P , T , and f O "SUB 2" , a small amount of each constituent oxide will reduce to metal and dissolved into the Pd, forming an alloy. Due to the extraordinary stability of dilute alloys of Pd with Mg, Al, and Si, these metals dissolved into the Pd in amounts easily measured with the electron microprobe at f O "SUB 2" s that can be achieved with conventional gas-mixing techniques. The activity-composition relations for Pd-Mg, -Al, and -Si alloys were determined by equilibrating Pd at fixed f O "SUB 2" and T with periclase, corundum, and cristobalite (a "SUB oxide" identical to 1). -from Authors
AN:  (1048998); 94K-11443

Record 46 of 393 in GEOBASE 1/90-11/97

TI:  Experimental study on the join forsterite-albite-anorthite at 35 kbar and its significance on the upper mantle petrology.
AU:  Bansal,-N.; Gupta,-A.-K.
SO:  Indian-Journal-of-Earth-Sciences. 1993. 20(2), pp 104-115.
AB:  The join forsterite-albite-anorthite has been studied experimentally at 35 kbar in the temperature range of 1200 to 1700 degrees C. Altogether 80 experiments have been performed on 42 compositions with the solid media 'anvil-with-hole' high pressure apparatus. The liquidus phase relations of the join are characterized by the primary phase volumes of forsterite "SUB ss " , orthopyroxene, garnet, clinopyroxene and corundum. Experimental study of the join at 35 kbar shows following reactions: 1) forsterite + albite > enstatite + jadeite, 2) forsterite + anorthite > garnet, 3) orthopyroxene + kyanite pyrope + quartz, 4) forsterite + grossularite > pyrope + clinopyroxene + forsterite "SUB ss " . The phase equilibria study of the join shows complete disappearance of plagioclase and spinel at 35 kbar. Reference to previous studies at 28 kbar and the present investigation suggest that plagioclase- and/or spinel-bearing ultramafic rocks are unstable below 31.5 +/- 3.5 kbar (90-100 km). -from Authors
AN:  (1038724); 94K-06331

Record 47 of 393 in GEOBASE 1/90-11/97

TI:  Zn-rich hogbomite formed from gahnite in the metabauxites of the Menderes Massif, SW Turkey.
AU:  Yalcin,-U.; Schreyer,-W.; Medenbach,-O.
SO:  Contributions-to-Mineralogy-and-Petrology. 1993. 113(3), pp 314-324.
AB:  Gahnite, present as an accessory mineral in regionally metamorphosed low-grade diasporites, has reacted in adjacent higher-grade, corundum-bearing metabauxite equivalents (emeries) to form Zn-rich hogbomite, the 4H polytype. The initial hogbomite crystals grew epitactically along the octahedral faces of gahnite. This indicates a metamorphic reaction, probably involving a fluid, transporting mainly the elements Zn and Al. The overall reaction relations involving partial reduction may be subdivided into the initial univariant reaction, gahnite+diaspore+Ti-hematite+rutile = hogbomite+H "SUB 2" O+O "SUB 2" . This was followed, in the absence of gahnite, by compostional readjustment of hogbomite and Ti-hematite and the appearance of magnetite. Core to rim zoning profiles indicate that, with continued growth, the hogbomite crystals became poorer in Zn and Ti, but richer in Fe "SUP 2+" , while the Ti-contents of coexisting hematite increased. -from Authors
AN:  (0986228); 93K-07896

Record 48 of 393 in GEOBASE 1/90-11/97

TI:  Corundum-bearing garnet clinopyroxenites at Beni Bousera (Morocco) : original plagioclase rich gabbros recrystallized at depth within the mantle?
AU:  Kornprobst,-J.; Piboule,-M.; Roden,-M.; Tabit,-A.
SO:  Journal-of-Petrology. 1990. 31(3), pp 717-745.
AB:  The Beni Bousera ultramafic massif is composed of peridotite with subordinate garnet pyroxenite units which belong to two different families: the Type I pyroxenites, characterized by an Fe-enrichment trend and the Type II pyroxenites, characterized by high but nearly constant Mg/Fe ratios and highly variable concentrations of Ca and Al. Geochemical analyses leads to the conclusion that the Mg-rich Type II pyroxenite sheets resulted ultimately from the fractionation of a basaltic melt at low pressure, and from the accumulation of olivine, clinopyroxene, and plagioclase along dykes cross-cutting the surrounding peridotite. The high-pressure and high-temperature crystallization of the 'primary' cpx + gt + co assemblage was achieved deep in the mantle, after subduction and/or dragging down in convection currents of this particular piece of the lithosphere. Further ascent may have resulted in partial melting of peridotite and/or pyroxenite, and in the emplacement of the Type I pyroxenite sheets. -from Authors
AN:  (0835256); 90K-11563

Record 49 of 393 in GEOBASE 1/90-11/97

TI:  Petrochemistry and geochronology of pink granite from Songsak, East Garo Hills, Meghalaya.
AU:  Kumar,-S.
SO:  Journal,-Geological-Society-of-India. 1990. 35(1), pp 39-45.
AB:  The pink granite of Songsak area, East Garo Hills district, Meghalaya, intrusive into Precambrian gneisses is inferred to be S-type, peraluminous, low-calcium, post-kinematic granite. It is characterised by initial "SUP 87" Sr/ "SUP 86" Sr ratio of 0.728 +/-.002, high K "SUB 2" O, high differentiation index and presence of normative corundum. The major mineral constituents are perthitic microcline, fresh interstitial microcline, orthoclase with different degree of triclinisation, two generations of quartz and biotite. Sericitization of feldspars, presence of muscovite, rare chiastolite, fluorite and uraninite are other characteristics of the pink granites. Whole rock Rb-Sr dating assigns an age of 500 +/-40 m.y. -Author
AN:  (0821908); 90K-08579

Record 50 of 393 in GEOBASE 1/90-11/97

TI:  Aluminous reaction textures in orthoamphibole-bearing rocks: the pressure-temperature evolution of the high-grade Proterozoic of the Bamble sector, south Norway.
AU:  Visser,-D.; Senior,-A.
SO:  Journal-of-Metamorphic-Geology. 1990. 8(2), pp 231-246.
AB:  Aluminous reaction textures in orthoamphibole-bearing rocks from the Froland area, Bamble, south Norway, record the prograde pressure-temperature path of the high-grade Kongsbergian Orogeny (c. 1600-1500 Ma) and the low-mid amphibolite facies overprint during the Sveconorwegian Orogeny (c. 1100-1000 Ma). The rocks contain anthophyllite/gedrite, garnet, cordierite, biotite, quartz, andalusite, kyanite, Cr-rich staurolite, tourmaline, ilmenite, rutile and corundum in a variety of parageneses. The P-T path is deduced from petrographic observations, mineral chemistry and zoning, geothermometry and (N)FMASH equilibria. -from Authors
AN:  (0817496); 90K-06505

Record 51 of 393 in GEOBASE 1/90-11/97

TI:  The stability of hercynite and hercynite-gahnite spinels in corundum- or quartz-bearing assemblages.
AU:  Shulters,-J.-C.; Bohlen,-S.-R.
SO:  Journal-of-Petrology. 1989. 30(4), pp 1017-1031.
AB:  The equilibrium 3FeAl "SUB 2" O "SUB 4" + 3Al "SUB 2" SiO "SUB 5" = Fe "SUB 3" Al "SUB 2" Si "SUB 3" O "SUB 12" + 5 Al "SUB 2" O "SUB 3" (1) has been calibrated in the piston-cylinder apparatus. Experiments were carried out using well-calibrated NaCl furnace assemblies and Ag "SUB 80" Pd "SUB 20" capsules with oxygen fugacity buffered at or near iron-wustite. The equilibrium is located at less than 7.2 kb at 850 degreesC and between 8.0 and 8.2, 10.0 and 10.5, and 12.0 and 12.2 kb at 900, 1000, and 1100 degreesC, respectively. Experiments have also been conducted to determine the effect of gahnite (ZnAl "SUB 2" O "SUB 4" ) component in spinel on equilibrium (1). Graphite capsules were used with oxygen fugacity buffered at or near graphite-CO-CO "SUB 2" . The addition of zinc displaces the reaction to higher pressures. A thermobarometer based on equilibrium (1) is applicable in high-grade metapelitic rocks. Failure of equilibrium (1) to intersect the equilibrium 3FeAl "SUB 2" O "SUB 4" + 5 SiO "SUB 2" = Fe "SUB 3" Al "SUB 2" Si "SUB 3" O "SUB 12" + 2 Al "SUB 2" SiO "SUB 5" (2) indicates that the equilibrium corundum + quartz = sillimanite is metastable at all pressures and temperatures. This implies that co-occurrences of corundum and quartz in granulites are metastable. -from Authors
AN:  (0805929); 90K-03158

Record 52 of 393 in GEOBASE 1/90-11/97

TI:  Petrology and retrograde P -T path in granulites of the Kanskaya formation, Yenisey range, eastern Siberia.
AU:  Perchuk,-L.; Gerya,-T.; Nozhkin,-A.
SO:  Journal-of-Metamorphic-Geology. 1989. 7(6), pp 599-617.
AB:  The Kanskaya formation in the Yenisey range, Eastern Siberia is a newly studied example of retrogression of granulite facies rocks. The formation consists of two stratigraphical units: the lower Kuzeevskaya group and the upper Atamanovskaya group. Rocks from both of these units show rare reaction textures such as replacement of cordierite by garnet, sillimanite and quartz, silimanite coronas around spinel and corundum, and garnet rims around plagioclase in metabasites, while plagioclase rims around garnet can be seen in associated metapelites. Individual samples yield P -T paths ranging from 100 degreesC/kbar to 140 degreesC/kbar depending on their locations with respect to the large Tarakskiy granite pluton. In places the 100 degreesC/kbar path changed to the 140 degreesC/kbar due to the influence of the intrusion. In a P -T diagram these trajectories are subparallel lines, whose P -T maxima define the Archaean geotherm between 3.1 and 2.7Ga, determined isotopically. A petrological model for P -T evolution of the Kanskaya formation is proposed. -from Authors
AN:  (0804075); 90K-02283

Record 53 of 393 in GEOBASE 1980-1989

TI:  Calibration and applications of spinel equilibria in the system FeO-Al"SUB 2"O"SUB 3"-SiO"SUB 2" ( thermobarometer).
AU:  BOHLEN,-S.-R.; DOLLASE,-W.-A.; WALL,-V.-J.
SO:  Journal-of-Petrology. 1986. 27(5), pp 1143-1156.
AB:  A new thermobarometer, based on the equilibrium 3 FeAl"SUB 2"O"SUB 4" (hercynite) + 5 SiO"SUB 2" (quartz) = Fe"SUB 3"Al"SUB 2"Si"SUB 3"O"SUB 12" (almandine) + 2 Al"SUB 2"SiO"SUB 5" (sillimanite) has been calibrated with experiments carried out in the piston-cylinder appartaus. Calibration of this equation allows calculation of the equilibrium: 3 FeAl"SUB 2"O"SUB 4" + 3 Al"SUB 2"SiO"SUB 5" = Fe"SUB 3"Al"SUB 2"Si"SUB 3"O"SUB 12" + 5 Al"SUB 2"O"SUB 3" (corundum). Thermobarometers based on the above equilibria are widely applicable in granulite facies rocks and yield pressure/temperature data that are consistent with other well-calibrated barometers and thermometers. -from Authors
AN:  (0712610); 88P-1719


Record 54 of 393 in GEOBASE 1980-1989

TI:  Metamorphic history of sapphirine-bearing and related magnesian gneisses from Namaqualand, South Africa.
AU:  WATERS,-D.-J.
SO:  Journal-of-Petrology. 1986. 27(2), pp 541-565.
AB:  Sapphirine occurs with cordierite, phlogopite, spinel, sillimanite, corundum, orthopyroxene, and gedrite in granulite facies Mg- and Al-rich paragneisses within the low P, high T Namaqualand Metamorphic Complex. The gneisses reveal a 3-stage textural history. Sapphirine appeared during a second stage of prograde mineral growth which produced nodular structures and intergrowths involving spinel, corundum, and sillimanite, pseudomorphing an earlier generation of coarse, amphibolite facies minerals. A third generation of coarse, cross-cutting mainly hydrous minerals (gedrite, kornerupine, phlogopite) is sporadically developed. The mineral textures indicate sapphirine growth under increasing T, decreasing a(H"SUB 2"O), and constant or slightly increasing P. The preservation of prograde reaction textures during fine-grained mineral growth probably results from the reduced importance and/or more CO"SUB 2"-rich composition of the metamorphic fluid under granulite facies conditions in these refractory rocks. Aqueous fluids were locally reintroduced after the metamorphic peak. -from Author
AN:  (0619522); 87R-1490


Record 55 of 393 in GEOBASE 1980-1989

TI:  Subsolidus and partial melting reactions in the quartz-excess CaO + MgO + A"SUB 2"O"SUB 3" + SiO"SUB 2" + H"SUB 2"O system under water- excess and water-deficient conditions to 10 kb: some implications for the origin of peraluminous melts from mafic rocks.
AU:  ELLIS,-D.J.; THOMPSON,-A.-B.
SO:  Journal-of-Petrology. 1986. 27(1), pp 91-121.
AB:  Experimental results up to 10 kb pressure are presented on the stability of amphibole in the quartz-excess CaO + MgO + Al"SUB 2"O + SiO"SUB 2" + H"SUB 2"O (CMASH) system under H"SUB 2"O-excess and H"SUB 2"O-deficient conditions. Amphibole is stable above the solidus under H"SUB 2"O-excess conditions whereas under H"SUB 2"O-deficient conditions dehydration melting of amphibole-bearing assemblages defines the solidus. A theoretical analysis of the partial melting of forsterite-bearing assemblages in the CaO + MgO + Al"SUB 2"O"SUB 3" + SiO"SUB 2" + H"SUB 2"O system shows that under H"SUB 2"O-excess conditions partial melting may generate corundum-normative (but low SiO"SUB 2") melts from a peridotite source at shallow depths.-from Authors
AN:  (0619508); 87P-2961


Record 56 of 393 in GeoRef Disc 5: 1997-2001/10

TI:  High-pressure aluminous mafic rocks from the Ronda peridotite massif, southern Spain; significance of sapphirine- and corundum-bearing mineral assemblages.
AU:  Morishita-Tomoaki; Arai-Shoji; Gervilla-Fernando
SO:  Lithos. 57; 2-3, Pages 143-161. 2001. 
FTXT:  ScienceDirect (tm) http://www.sciencedirect.com/science?_ob=GatewayURL&_origin=SilverLinker&_urlversion=4&_method=citationSearch&_volkey=0024%2d4937%2357%23143&_version=1&md5=78c90cb938cf07aa8a996df1fb56b9af
PB:  Elsevier. Amsterdam, International. 2001.
PY:  2001
AB:  We firstly present detailed microtextural relationships in sapphirine- and corundum-bearing aluminous mafic rocks alternating with peridotites from the Ronda massif, southern Spain. Garnet and clinopyroxene are the main phases in the aluminous mafic rocks. Garnet is partially to completely kelyphitized. Clinopyroxene (CPX I) has high Al (sub 2) O (sub 3) content in the core (up to 16 wt.%) and is partially converted to spherical symplectitic aggregates consisting of lower-Al (sub 2) O (sub 3) clinopyroxene (CPX II) (<5 wt.%) and plagioclase. Corundum is associated with spinel and plagioclase. Sapphirine occurs in two different mineralogical associations, i.e., as elongated lamellae within CPX I and as very fine-grained crystals in plagioclase-rich domain. The sapphirine+plagioclase aggregate suggests the former presence of kyanite as one of reactants. Sapphirine is partially converted to symplectitic aggregate of spinel and plagioclase. The earliest metamorphic mineral assemblage recorded in the aluminous mafic rock was garnet + clinopyroxene + or - kyanite + or - corundum, i.e., eclogitic mineral assemblages, at P> or =1.5 GPa and T> or =900 degrees C. Many reaction textures were developed during decompression possibly coupled with cooling. The latest P-T conditions recorded in the aluminous mafic rock were at P=1 GPa and T = 800-900 degrees C. This decompression had possibly followed the compression of plagioclase-rich, low-pressure cumulate or residue.
AN:  2001-055425

Record 57 of 393 in GeoRef Disc 5: 1997-2001/10

TI:  Solubility of corundum+kyanite in H2O at 700C, 1 and 1.5 GPa; evidence for high Al mobility in deep metasomatic environments.
AU:  Manning-Craig-E
BK:  In: Geological Society of America, 1999 annual meeting.
BA:  Anonymous
SO:  Abstracts with Programs - Geological Society of America. 31; 7, Pages 354. 1999. 
PB:  Geological Society of America (GSA). Boulder, CO, United States. 1999.
PY:  1999
AB:  The occurrence of aluminosilicates in veins and segregrations in deep metamorphic rocks is apparently at odds with low Al solubility inferred from low-pressure geothermal fluids and experiments and suggests variation in aqueous Al mobility with depth. To investigate this, experiments were conducted in a piston-cylinder apparatus at 700 degrees C, 1 and 1.5 GPa, using 1' diameter graphite-NaCl furnaces. H2O+natural kyanite crystals+ or -synthetic Al (sub 2) O (sub 3) and SiO (sub 2) powders were sealed in 5 mm OD Pt capsules and run for 7.5 to 120 hr. Because of higher solubility of Si than Al, a sheath of hexagonal corundum crystals grew on kyanite surfaces, fixing aqueous Al and Si concentrations at corundum+kyanite saturation. Quenched fluids were extracted from the charge and analyzed by ICP-AES. Erratic final fluid compositions in early experiments on kyanite+H (sub 2) O resulted from strong initial disequilibrium. Addition of highly soluble Al (sub 2) O (sub 3) and SiO (sub 2) powders, in amounts sufficient to bring the initial fluid closer to its final equilibrium composition, circumvented this problem. Equilibrium fluid compositions at 1 and 1. 5 GPa were respectively: [Al] = 6.2+ or -0.6 and 8.6+ or -2.3 mmol/kg, and [Si] = 0.318+ or -0.036 and 0.256 + or - 0.025 mol/kg. Si contents are within 2 standard deviations of those predicted from Manning (1994). Al concentrations are nearly ten times higher than those of Becker et al. (1983), who used 12 hr run times and corundum spheres. The results agree with the pressure-dependence of corundum solubility based on extrapolations of results of Walther (1997). Combination of the data of this study and of Walther (1997) suggests revised standard partial molal thermodynamic properties of aqueous HAlO (sub 2) at 25 degrees C, 1 bar: Gf = -208 kcal/mol, S = 5 cal/molK, V = 13 cm (super 3) /mol, and Cp = 40 cal/molK. The results imply that at constant temperature, Al solubility in H (sub 2) O coexisting with aluminosilicates increases strongly from 0.2 to 1 GPa, and that Al is highly mobile in H (sub 2) O in deep (>0.5 GPa) metasomatic environments. Decompression of simple aqueous fluids originating in the middle and lower crust can thus readily produce vein aluminosilicates in deep metamorphic regions.
AN:  2001-049848

Record 58 of 393 in GeoRef Disc 5: 1997-2001/10

TI:  Formation of orange hibonite, as inferred from some Allende inclusions.
AU:  Simon-S-B; Davis-A-M; Grossman-L
SO:  Meteoritics and Planetary Science. 36; 3, Pages 331-350. 2001. 
PB:  Meteoritical Society. Fayetteville, AR, United States. 2001.
PY:  2001
AB:  We studied three fluffy Type A refractory inclusions from Allende that contain orange hibonite. The melilite in the present samples is very Al-rich, averaging Aak (sub 6) , Aak (sub 14) , and Aak (sub 12) in the three samples studied. Hibonite in two inclusions, unlike that in Murchison, has low rare earth element abundances of <10XCI; in the other inclusion, the hibonite, melilite and perovskite have Group II-like patterns. The hibonite and melilite in all three inclusions studied have excess (super 26) Mg consistent with ( (super 26) Al/ (super 27) Al) (sub I) = 5X10 (super -5) . Much of the hibonite and some of the spinel in these inclusions is corroded. These phases are found enclosed in melilite, but based on bulk compositions and phase equilibria, hibonite should not be an early-crystallizing phase in these inclusions. We conclude that the hibonite and probably some of the spinel is relic. Reversely zoned melilite, rounded spinel and isotopically heavy Mg in the inclusions probably reflect reheating events that involved melting and evaporation. Alteration of the gehlenitic melilite gave rise to some rare phases, including corundum and nearly pure CaTs pyroxene. Studies have shown that blue hibonite contains Ti (super 3+) while orange hibonite does not (Ihinger and Stolper, 1986; Beckett et al., 1988). Orange hibonite formed either under oxidizing conditions (such as at oxygen fugacities at least seven orders of magnitude greater than that of a solar gas at 1700 K), or under conditions reducing enough (e.g., solar) that it contained Ti (super 3+) , which was later oxidized in situ. Although V and Ce oxides are volatile at the temperature and range of oxygen fugacities at which orange hibonite is known to be stable, we find that (a) the hibonite is V-rich ( approximately 1 wt% V (sub 2) O (sub 3) ) and (b) there are no negative Ce anomalies in Allende hibonite. This indicates that the hibonite did not form by condensation under oxidizing conditions. In addition, there are slight excesses of Ti+ Si cations relative to Mg+ Fe cations (up to 0.1 of 0.8 cations per 19 oxygen anions), probably reflecting the original presence of Ti (super 3+) . The results of this study strongly support the suggestion (Ihinger and Stolper, 1986) that Allende hibonite originally formed under reducing conditions and was later oxidized. Oxygen fugacities within approximately 2-3 orders of magnitude of that of a solar gas are implied; otherwise, strong Ce and V depletions would be observed.
AN:  2001-049349

Record 59 of 393 in GeoRef Disc 5: 1997-2001/10

TI:  Geographic variations in concentration of mineral inclusions in muong nong-type Australasian tektites; implications regarding the location of the Australasian tektite source crater.
AU:  Dass-J-D; Glass-B-P
BK:  In: Lunar and planetary science, XXX; Papers presented to the Thirtieth lunar and planetary science conference.
BA:  Anonymous
SO:  Abstracts of Papers Submitted to the Lunar and Planetary Science Conference. 30; Pages ; abstr. no. 1081. 1999. 
PB:  Lunar and Planetary Science Conference. Houston, TX, United States. 1999.
PY:  1999
AB:  Mineral inclusions (primarily zircon and an Al (sub 2) SiO (sub 5) phase) were found in 19 of 32 layered Australasian tektites. The highest concentrations are in samples from Muong Phin, Laos. Our preliminary data are consistent with a source crater in southern Laos or adjacent area.
AN:  2001-042542

Record 60 of 393 in GeoRef Disc 5: 1997-2001/10

TI:  Weakening associated with the diaspore-corundum dehydration reaction in metabauxites; an example from Naxos (Greece).
AU:  Urai-J-L; Feenstra-A
BK:  In: Evolution of structures in deforming rocks; in honour of Paul F. Williams.
BA:  White-J-C (editor); Bleeker-Wouter (editor); Elliott-Colleen (editor); Lin-Shoufa (editor); van-Staal-Cees-R (editor)
SO:  Journal of Structural Geology. 23; 6-7, Pages 941-950. 2001. 
FTXT:  ScienceDirect (tm) http://www.sciencedirect.com/science?_ob=GatewayURL&_origin=SilverLinker&_urlversion=4&_method=citationSearch&_volkey=0191%2d8141%2323%23941&_version=1&md5=14226140cb96ee50d38dc705b670ed83
PB:  Pergamon. Oxford, International. 2001.
PY:  2001
AB:  Metabauxite lenses embedded in marble on Naxos consist of diasporites below the 420 degrees C isograd, and dehydrate into corundum-rich rocks with increasing grades of metamorphism. While the diasporites are essentially undeformed, the corundum-rich rocks are strongly deformed, even though both diasporites and corundum-rich rocks are much stronger than the surrounding intensely deformed marbles. The observed structures can be explained as an effect of high fluid pressures during the prograde diaspore-corundum dehydration reaction, which causes dramatic temporary weakening of the metabauxites (to a strength comparable to that of the surrounding deforming marbles). Deformation of the metabauxite is thus largely restricted to the time span the phase transformation occurred, allowing the dehydrating bauxite mass to deform together with the surrounding marbles.
AN:  2001-042304

Record 61 of 393 in GeoRef Disc 5: 1997-2001/10

TI:  Pan-African magmatism and sedimentation in the NW Himalaya.
AU:  Islam-R; Upadhyay-R; Ahmad-T; Thakur-V-C; Sinha-A-K
BK:  In: Neoproterozoic crustal evolution and Indian-Gondwana linkage.
BA:  Roy-A-B (editor)
SO:  Gondwana Research. 2; 2, Pages 263-270. 1999. 
PB:  International Association for Gondwana Research. Osaka, Japan. 1999.
PY:  1999
AB:  Correlation of early Palaeozoic, Pan-African (500+ or -50 Ma) granites that intruded the Chail, Salkhala, Haimanta Formations in the Lesser Himalaya, Zanskar crystallines, and Lower Taglang La of Tso-Morari crystallines in the northwestern Himalaya, is based on the field relationship, tectonic setting, mineralogical and geochemical characteristics, and isotope dating of the granites. These granite plutons exhibit identical petrographical and geochemical character. The mineralogical composition of the granites is quite similar, consisting of quartz, K-feldspar, plagioclase feldspar, biotite, muscovite, garnet, tourmaline, + or -cordierite, andalusite and sillimanite fibrolite. The granite which are massive and inequigranular in the core of the plutons, show strongly foliated character indicating development of ductile shear zone at the margins. These are peraluminous S-type granites having high A/CNK value (>1). Presence of normative corundum, rounded shape of zircon, and high initial Sr ratio suggest crustal source of the granites. Mantle normalized spider-diagram exhibits similar characters for all these granitoids. The intrusion of the Pan-African granites mark an abrupt end of the sedimentation that continued virtually uninterrupted from Palaeoproterozoic. The sudden break in sedimentation towards the terminal phases of the Lower Cambrian has been observed in almost all parts in Lesser as well as the Tethys Himalaya. Occurrences of large number of plutons along different tectonic belts of northwestern Himalaya are indicative of widespread tectono-thermal event during early Palaeozoic (500+ or -50 Ma). The bracketing of the two features like, the break in sedimentation during post-Late Cambrian and the intrusion of granites around 500+ or -50 Ma, is considered to be the result of a strong diastrophic orogenic event correlatable to the late phases of the Pan-African Orogeny in Africa.
AN:  2001-041379

Record 62 of 393 in GeoRef Disc 5: 1997-2001/10

TI:  Corundum megacrysts and corundum-bearing xenoliths in the French Bar "dike", Lewis and Clark County, Montana.
AU:  Berg-Richard-B
BK:  In: Geological Society of America, Rocky Mountain Section, 52nd annual meeting.
BA:  Anonymous
SO:  Abstracts with Programs - Geological Society of America. 32; 5, Pages 2. 2000. 
PB:  Geological Society of America (GSA). Boulder, CO, United States. 2000.
PY:  2000
AB:  The French Bar "dike", an amygdaloidal trachybasalt sill 1-2 meters thick in metasedimentary beds of the Proterozoic Belt Supergroup, is exposed 23 km northeast of Helena along the Missouri River. This sill contains quartz, almandine, and corundum megacrysts, all generally <6 mm. Megacrysts are interpreted to be xenocrysts on the basis of reaction rims--biotite around corundum, a layer now altered to a waxy, tan clay surrounded by a biotite rim around almandine, and the same tan clay around quartz. Corundum megacrysts are transparent and colorless to very pale green and greenish blue; many have a tabular shape. Small (generally <2 cm) angular to subrounded xenoliths of diopsidic marble, amphibolite, quartzite, siltstone, and corundum-bearing metamorphic rock occur sparingly. Some corundum-bearing xenoliths contain relatively large idioblastic corundum crystals up to 6 mm in a mosaic of calcic labradorite, accompanied by lesser hornblende (pargasitic?), and biotite. Other xenoliths contain ovoid masses of prismatic corundum crystals intergrown with margarite and surrounded by a thin layer of fine-grained, dark green spinel surrounded by calcic labradorite, diopside, garnet, and an amphibole. The Precambrian basement is the most likely source of marble, amphibolite, and those xenoliths that contain larger corundum crystals. Xenoliths with prismatic corundum may be pelites that were metamorphosed after inclusion in the magma. Obviously this small intrusive body with sparse corundum megacrysts cannot be a significant source for corundum in the large alluvial sapphire deposits along the Missouri River. However similar igneous rocks that included corundum-bearing metamorphic rocks from the Precambrian basement may have liberated corundum crystals in sufficient quantities to form the alluvial sapphire deposits.
AN:  2001-040785

Record 63 of 393 in GeoRef Disc 5: 1997-2001/10

TI:  Trace-element thermobarometry using titanium in garnet.
AU:  Keane-S-D; Essene-E-J; Manning-C-E
BK:  In: Seventh annual V. M. Goldschmidt conference.
SO:  LPI Contribution. 921; Pages 110-111. 1997. 
PB:  Lunar and Planetary Institute. Houston, TX, United States. 1997.
PY:  1997
AN:  2001-036950

Record 64 of 393 in GeoRef Disc 5: 1997-2001/10

TI:  Effect of carbon dioxide on dehydration melting reactions and melt compositions in the lower crust and the origin of alkaline rocks.
AU:  Kaszuba-John-P; Wendlandt-Richard-F
SO:  Journal of Petrology. 41; 3, Pages 363-386. 2000. 
FTXT:  SwetsNet (European Mirror) http://www.swetsnet.nl/link/access_db?issn=00223530&vol=00041&iss=00003&page=363 SwetsNet (US Mirror) http://www.swetsnet.com/link/access_db?issn=00223530&vol=00041&iss=00003&page=363 EBSCO Online http://www.ebsco.com/online/direct.asp?ArticleID=LLAKPX6A7V7G89692GQ4
PB:  Oxford University Press. Oxford, United Kingdom. 2000.
PY:  2000
AB:  Dehydration melting experiments of alkali basalt associated with the Kenya Rift were performed at 0.7 and 1.0 GPa, 850-1100 degrees C, 3-5 wt % H (sub 2) O, and f (sub O2) near nickel-nickel oxide. Carbon dioxide [X (sub CO2) = molar CO (sub 2) /(H (sub 2) O+CO (sub 2) ) = 0.2-0.9] was added to experiments at 1025 and 1050 degrees C. Dehydration melting in the system alkali basalt-H (sub 2) O produces quartz- and corundum-normative trachyandesite (6-7.5 wt % total alkalis) at 1000 and 1025 degrees C by the incongruent melting of amphibole (pargasite-magnesiohastingsite). Dehydration melting in the system alkali basalt-H (sub 2) O-CO (sub 2) produces nepheline-normative tephriphonolite, trachyandesite, and trachyte (10.5-12 wt % total alkalis). In the latter case, the solidus is raised relative to the hydrous system, less melt is produced, and the incongruent melting reaction involves kaersutite. The role of carbon dioxide in alkaline magma genesis is well documented for mantle systems. This study shows that carbon dioxide is also important to the petrogenesis of alkaline magmas at the lower pressures of crustal systems. Select suites of continental alkaline rocks, including those containing phonolite, may be derived by low-pressure dehydration melting of an alkali basalt-carbon dioxide crustal system.
AN:  2001-024023

Record 65 of 393 in GeoRef Disc 5: 1997-2001/10

TI:  Corundum-bearing ultramafic veins in the Rymmen Gabbro, southern Sweden; isochemical mineral alteration.
AU:  Claeson-Dick-T
SO:  Neues Jahrbuch fuer Mineralogie. Abhandlungen. 175; 1, Pages 1-27. 1999. 
PB:  E. Schweizerbart'sche Verlagsbuchhandlung. Stuttgart, Federal Republic of Germany. 1999.
PY:  1999
AN:  2001-017853

Record 66 of 393 in GeoRef Disc 5: 1997-2001/10

TI:  Study of alkaline rocks and carbonatites in parts of eastern India (IGCP Project No. 314).
AU:  Ghosh-Roy-A-K
BK:  In: Extended abstracts of progress reports; field season 1991-92; eastern region.
BA:  Basu-K-K (prefacer)
SO:  Records of the Geological Survey of India. 126, Part 3; Pages 189-190. 1993. 
PB:  Geological Survey of India. Calcutta, India. 1993.
PY:  1993
AN:  2001-016555

Record 67 of 393 in GeoRef Disc 5: 1997-2001/10

TI:  Discovery of the eclogite and its petrography in the northern Dabie Mountain.
AU:  Xu-Shutong; Liu-Yican; Su-Wen; Wang-Rucheng; Jiang-Laili; Wu-Weiping
SO:  Chinese Science Bulletin. 45; 3, Pages 273-278. 2000. 
PB:  Science Press. Beijing, China. 2000.
PY:  2000
AB:  Eclogite from the Northern Dabie Mountain is a new finding by the authors. These eclogites in foliated peridotite are enveloped by banded gneiss and occur in the mafic-ultramafic rock belt. They are mainly composed of omphacite, garnet, diopside, orthopyroxene, amphibole, plagioclase and magnetite, and a small amount of rutile, spinel, olivine and corundum. The mineral association of peak metamorphism of the eclogite is omphacite+garnet+rutile. The existence of eclogite in the Northern Dabie Mountain implies that there was an eclogitic metamorphism prior to the granulitic facies one in the mafic-ultramafic rock belt.
AN:  2001-009314

Record 68 of 393 in GeoRef Disc 5: 1997-2001/10

TI:  Petrogenesis and evolution of the Dineibit El-Qulieb hyperaluminous leucogranite, southeastern Desert, Egypt; petrological and geochemical constraints.
AU:  El-Sayed-Mohamed-M; El-Nisr-Said-A
SO:  Journal of African Earth Sciences (1994). 28; 3, Pages 703-720. 1999. 
PB:  Pergamon. Oxford, United Kingdom. 1999.
PY:  1999
AB:  The Dineibit El-Qulieb Leucogranite exhibits most features of l-type granitoids (calc-alkaline affinity, relatively high Na (sub 2) O, moderate values of Rb, Ba, LREE, Rb/Sr and low Rb/Ba with the presence of magnetite and titanite as the main accessories). On the other hand, they possess hyperaluminous (molar A/CNK = 1.22-1.43) and high normative corundum ( approximately 5%), which are in contrast to typical l-type granitoids. The REE patterns are characterised by fractionated LREE and relatively flat HREE with pronounced negative Eu anomalies. The investigated rocks have low K/Rb and high Zr/Y ratios reflecting a typical mature continental-arc environment. The absence of recrystallised phases and the undepleted and flat HREE of the Dineibit El-Qulieb Leucogranite pattern argue against its formation by partial melting of crustal materials. Based on the petrological and geochemical features, the Dineibit El-Qulieb Leucogranite can be generated by fractional crystallisation of mafic magma. The Qulieb leucogranites are characterised by LILE enrichment, normative corundum-rich, strongly peraluminous compositions and associated with miarolitic cavities and pegmatitic patches suggesting the role of the aqueous fluids released from the downgoing slab during subduction. The main fractionating phases were hornblende, biotite, plagioclase and alkali feldspars. Based on the modelling of major elements, the least differentiated adamellite sample requires 91% crystal fractionation, mainly of hornblende, plagioclase, K-feldspar and biotite, from dioritic liquid. On the other hand, the most felsic investigated adamellite sample can be generated by 29% fractional crystallisation of plagioclase, K-feldspar and biotite from the most basic adamellite sample.
AN:  2001-009229

Record 69 of 393 in GeoRef Disc 5: 1997-2001/10

TI:  Condizioni di pressione e temperatura del termometamorfismo nel sistema geotermico di Larderello
Translated Title:  Pressure and temperature conditions during the contact metamorphism in the geothermal system of Larderello.
AU:  Gianelli-G
SO:  Atti della Societa Toscana di Scienze Naturali Residente in Pisa, Memorie, Serie A: Processi Verbali. 105; Pages 17-35. 1998. 
PB:  Arti Grafiche Pacini Mariotti. Pisa, Italy. 1998.
PY:  1998
AB:  The P-T conditions of the metapelites forming the contact aureole around the granite intrusions at Larderello are estimated as follows: a pressure range of approximately 50-100 MPa and a temperature range of approximately 400-650 degrees C. Using modified AFM phase diagrams it was possible to evaluate the stability fields of the mineral assemblages compatible with the chemical composition of the pelitic rocks found in the thermometamorphic aureole by a number of geothermal wells at Larderello. The rocks belong both to the Triassic Verrucano Formation and (more commonly) to Paleozoic and pre-Sudetic Units. The phase diagrams have been constructed by using the program PeRpLeX and an updated thermodynamic data bank. The pressure conditions are constrained by the present-day depth of the roof of the intrusions (approximately 2.5-4 km) and the estimated uplift ratio (0.2 mm/yr) and the age of the intrusion and thermometamorphic minerals (0.5 to about 4 Ma). The temperature range is constrained by paragenetic, fluid inclusion and isotopic data. At such low pressure the pelite re-crystallisation formed mineral assemblages characterised by biotite and andalusite (besides quartz, muscovite, chlorite and, in places, chloritoid). By increasing temperature we observe the prograde disappearance of chlorite and the crystallisation of cordierite and, in places, corundum. Temperatures equal or in excess of 500 degrees C probably occurred in a plastic, impervious layer close to the granite intrusions and characterised by a very steep thermal gradient. On the contrary, lower temperatures occurred along a crustal section with different characteristics: quasi-plastic to brittle mechanical behaviour, low thermal gradient and possible presence of hydrothermal circulation. A diffuse crystallisation of biotite associated with andalusite characterised this shallow crustal section. It is important to note that, at the pressure of 50-100 MPa garnet can be present at relatively low temperatures (below 500 degrees C) only in Fe-rich rocks. More commonly this mineral is found in micaschist and gneiss and is often present as a relict phase. Its occurrence is related to a pre-Alpine thermal event, characterised by HT-LP conditions. The pressure was at least 400 MPa.
AN:  2001-007619

Record 70 of 393 in GeoRef Disc 5: 1997-2001/10

TI:  Margarite-corundum phyllites from the Appalachian orogen of South Carolina; mineralogy and metamorphic history.
AU:  Ranson-William-A
SO:  American Mineralogist. 85; 11-12, Pages 1617-1624. 2000. 
PB:  Mineralogical Society of America. Washington, DC, United States. 2000.
PY:  2000
AB:  Phyllites from the Charlotte belt (Central Piedmont) of South Carolina contain porphyroblasts of black corundum in a matrix of margarite and minor muscovite. The margarite-corundum phyllites formed during Ordovician (?) amphibolite facies metamorphism of an aluminous protolith with a probable mineralogy of pyrophyllite, diaspore, and calcite through reactions such as 6Dia+Prl+2Cal = 2Mrg+2CO (sub 2) +2H (sub 2) O and 2Dia = Crn+H (sub 2) O. The protolith was probably a hydrothermally altered felsic tuff of Late Proterozoic to Cambrian age. Based on a whole-rock chemical analysis of margarite-corundum phyllite, the protolith is believed to have consisted of about 7 mol% calcite, 23 mol% pyrophyllite, and 70 mol% diaspore. A T-X (sub CO2) plot of pertinent reactions in the system CaO-Al (sub 2) O (sub 3) -SiO (sub 2) -H (sub 2) O-CO (sub 2) shows that in the presence of an H (sub 2) O-rich fluid (X (sub CO2) approximately 0.08) margarite began forming by the reaction 6Dia+Prl+2Cal = 2Mrg+2CO (sub 2) +2H (sub 2) O at about 350 degrees C at 5 kbar. This reaction continued along a univariant path until pyrophyllite and calcite were consumed. The remaining diaspore was converted to corundum by the reaction 2Dia = Crn+H (sub 2) O at about 430 degrees C for this H (sub 2) O-rich fluid at 5 kbar. The upper temperature limit of this assemblage is constrained by the reaction Mrg = Crn+An+H (sub 2) O, which should occur at about 575 degrees C under this pressure. The absence of plagioclase in these rocks suggests that the conditions of this reaction were never achieved. Fluids associated with subsequent Alleghanian greenschist facies metamorphism reacted with corundum to form fine-grained margarite at corundum margins.
AN:  2001-006278

Record 71 of 393 in GeoRef Disc 5: 1997-2001/10

TI:  A Csodi-hegy vulkani kozetenek geokemiaja es petrogenezise
Translated Title:  Geochemistry and petrogenesis of the volcanic rocks from Csodi Hill.
AU:  Harangi-S
BK:  In: Minerals of Csodi Hill, Dunabogdany.
BA:  Papp-G (editor)
SO:  Topographia Mineralogica Hungariae. 6; Pages 59-85. 1999. 
PB:  Herman Otto Museum. Miskolc, Hungary. 1999.
PY:  1999
AB:  The Middle Miocene subvolcanic rocks of Csodi Hill belong to the andesite-rhyodacite volcanic complex of the Visegrad Mts. They were formed between 14 and 16 Ma as a part of widespread Middle Miocene to Quaternary calc-alkaline volcanism along the northern and eastern part of the Pannonian Basin. The calc-alkaline volcanism at the western segment of the Carpathian volcanic arc occurred in a retreating subduction zone when the southward subduction of the European plate ceased and compressional tectonic field changed to extension. The present-day thickness of the crust and lithosphere beneath this area indicates that it belonged to the extended Pannonian Basin system. The origin of the calc-alkaline volcanic activity in the Western Carpathian Arc is a subject of debate i.e. whether there is a direct relationship between subduction and volcanism or melt generation occurred due to thinning of lithosphere resulting in partial melting of metasomatised lithospheric mantle. Garnet-bearing volcanic rocks belong to the earliest products of the calc-alkaline volcanism. K/Ar radiometric dating implies that the volcanic rock from Csodi Hill was formed about 16 Ma. Garnet-bearing volcanic rocks are rare world-wide and only limited data are available about them. Table I summarises the main information about garnet-bearing volcanic rocks from different localities. Rare occurrences of garnet-bearing volcanic rocks may be explained by the limited stability field of Cabearing and Mn-poor almandine garnets. Experimental studies pointed out that they can crystallise H (sub 2) O-rich silicic magma at high pressure (8-12 kbar). Preservation of euhedral garnet phenocrysts implies rapid ascent of the host magmas. Almandine garnets are usually hosted by peraluminous (S-type) SiO (sub 2) -rich volcanic rocks which are derived by anatexis of granulite facies metapelitic lower crustal rocks. On the other hand there are many examples of diopside-normative (I-type) garnet-bearing volcanic rocks which were formed from mantle-derived magmas. The volcanic rock of Csodi Hill is classified as medium-K garnet-bearing biotite-dacite. Garnets (Alm = 65-70% Gro = 9-14% are primary phenocrysts i.e. they crystallised from the magma. They are coexisting with calcic plagioclase (An = 77-86%) and biotite. Amphibole and orthopyroxene occur subordinately and they are usually strongly altered. The groundmass consists of intermediate plagioclase and subordinate Fe-Ti oxide glass and secondary minerals. Major element composition of a garnet-bearing (VH-CSH) and a garnet-free (L-CSH) sample from Csodi Hill is presented in Table II. Slightly peraluminous composition is supported by the appearance of normative corundum ( c = 1.48-1.88) and the A/CNK>1 ratio (A/CNK = 1.06-1.09). The N-MORB normalised trace element pattern of the dacite from Csodi Hill shows Nb and Ti trough and positive Pb anomaly which are typical of subduction-related volcanics. Comparing of the Csodi dacite with the garnet-bearing rhyodacites from the soutwestern part of the Visegrad Mts. the main differences are at the Ti-Lu range. The latter ones show strong depletion in Y and in heavy rare-earth elements which is similar to the garnet-bearing rhyolites from the Pyrenees. Chondrite-normalised rare-earth element pattern of the Csodi dacite is smooth without any Eu-anomaly. The (La/Yb)ch ratio is in the range of the garnet-free andesites of the Visegrad Mts. On the contrary the garnet-bearing rhyodacites have a strong depletion in the heavy rare-earth elements and show a weak negative Eu anomaly. Radiogenic isotope ratios ( (super 87) Sr/ (super 86) Sr and (super 143) Nd/ (super 144) Nd) of the Csodi dacite are comparable with other garnet-bearing volcanic rocks in the area. They have high (super 87) Sr/ (super 86) Sr (0.7092-0.7100) and low (super 143) Nd/ (super 144) Nd isotope ratio (0.51230-0.51235) whereas garnet-free volcanics show more depleted isotope composition ( (super 87) Sr/ (super 86) Sr = 0.7070-0.7092; (super 143) Nd/ (super 144) Nd = 0.51233-0.51242). Major element chemical variation of the volcanic rocks of the Visegrad Mts. shows a gap in the range of SiO (sub 2) = 62-66 wt%. Garnet-bearing volcanic rocks have higher SiO (sub 2) and total alkali content than the garnet-free volcanics. Incompatible trace element ratios and radiogenic isotope ratios are not consistent with a simple fractional crystallisation or assimilation and fractional crystallisation (AFC) model to explain the genesis of the Middle Miocene volcanic series of the Visegrad Mountains. A two-component mixing model has been also proposed recently invoking a mafic mantle-derived magma and a crustal-derived rhyolitic magma end-member. However distribution of data points in combined trace element and radiogenic isotope diagrams does not support this process as well. Therefore it appears that the Middle Miocene volcanic rocks of the Visegrad Mts. are not cogenetic i.e. they were formed from different parental magmas which could have been separated from each other. Primary magma of the Csodi dacite could have been generated in a metasomatised (H (sub 2) O-rich) lithospheric mantle source by relatively high degree of melting probably resulting in a silicic (andesitic) melt. The melt generation was initiated by thinning of lithosphere during the syn-rift period of the Pannonian Basin. Metasomatism was caused by subduction-related aqueous fluids before the Miocene magmatism. Major element chemistry and oxygen isotope data of the garnets of Csodi Hill indicate that they were crystallised at a pressure above 5-6 kbar (rather at about 8-10 kbar) corresponding to the crust-mantle boundary zone. We assume that crustal slivers might be incorporated into the primary andesitic magma resulting in an increase of Al (sub 2) O (sub 3) content. This allowed the high pressure crystallisation of garnet along with calcic plagioclase. Since the euhedral garnet phenocrysts are well preserved and the host rock does not show negative Eu-anomaly the Csodi dacite could have been formed from only a slightly differentiated melt ascended relatively fast to the surface. High pressure garnet and plagioclase fractionation could resulted in a more differentiated magma from which the garnet-bearing rhyodacites were generated.
AN:  2000-075234

Record 72 of 393 in GeoRef Disc 5: 1997-2001/10

TI:  Quantitative measurement of paramagnetic Fe (super 3+) in kaolinite.
AU:  Balan-Etienne; Allard-Thierry; Boizot-Bruno; Morin-Guillaume; Muller-Jean-Pierre
SO:  Clays and Clay Minerals. 48; 4, Pages 439-445. 2000. 
PB:  Clay Minerals Society. Clarkson, NY, United States. 2000.
PY:  2000
AB:  A method is proposed to measure the absolute concentration of paramagnetic Fe (super 3+) ions in kaolinite from various geochemical environments using powder X-band electron paramagnetic resonance (EPR) data. An Fe (super 3+) -doped corundum sample is used as a concentration standard. The Fe (super 3+) signal is calibrated by calculating the powder EPR spectra of Fe (super 3+) ions in corundum and low-defect kaolinite. The paramagnetic Fe (super 3+) concentration in other samples is obtained by an extrapolation procedure. This study provides a direct assessment of the iron distribution between isolated structural Fe (super 3+) ions and other iron species, such as Fe (super 3+) concentrated phases and Fe (super 2+) ions. The concentration of isolated structural Fe (super 3+) ranges between 200-3000 ppm and represents less than half of the total iron within kaolinite crystals.
AN:  2000-070305

Record 73 of 393 in GeoRef Disc 5: 1997-2001/10

TI:  1.4-Ga peraluminous granites in central New Mexico; petrology and geochemistry of the Priest Pluton.
AU:  Thompson-Amy-G; Barnes-Calvin-G
BK:  In: Proterozoic magmatism of the Rocky Mountains and environs (Part I).
BA:  Frost-Carol-D (editor)
SO:  Rocky Mountain Geology. 34; 2, Pages 223-243. 1999. 
PB:  University of Wyoming. Laramie, WY, United States. 1999.
PY:  1999
AB:  The Priest pluton is part of the suite of 1.4-Ga granitic plutons in North America. The pluton is a corundum normative, peraluminous, K-feldspar megacrystic granodiorite to quartz monzonite. It is characterized by: (1) high Mg/Mg+Fe; (2) high abundances of Al (sub 2) O (sub 3) , CaO, and large ion lithophile elements (e.g., Sr, Ba); and (3) low abundances of high field strength elements (e.g., Zr, Y). Major and trace element modeling suggests that variations in composition were produced by accumulation of K-feldspar and plagioclase, localized accumulation of plagioclase, biotite, and accessory minerals, and late-stage crystal fractionation of the residual melt. Plutons in the suite of 1.4 Ga, so-called "anorogenic" granitic plutons have been classified as A-type granites. Major and trace element abundances suggest that the Priest pluton is not A-type, but has more in common with S-type granites. In addition, typical tectonic classification techniques suggest that the pluton is either a volcanic-arc/syn-collisional or late orogenic granite. The pluton's intrusion was accompanied by highly partitioned, compressional deformation that is not typically associated with anorogenic, A-type plutons. The Priest pluton also is distinct from the nearby Sandia pluton, although the two plutons are nearly the same age. The Priest pluton has higher Mg number, alumina saturation index, and large ion lithophile element abundances as well as lower abundances of high field strength elements. The Priest pluton contains only biotite as its mafic phase, whereas the Sandia pluton contains biotite and hornblende. Differences in geochemistry between the Priest and Sandia plutons and the rest of the suite of 1.4 Ga granitic plutons suggest that the lower crust is a heterogeneous source region. Therefore, geochemical signatures that commonly are associated with particular tectonic settings may instead reflect heterogeneities in the source.
AN:  2000-069019

Record 74 of 393 in GeoRef Disc 5: 1997-2001/10

TI:  A quantitative X-ray diffraction study of mafic and ultramafic lithologies using the reference intensity method (RIM); a case study from Corundum Knob, Clay County, North Carolina.
AU:  Collins-J-E; Kath-Randy-L
BK:  In: Seventy-fifth annual meeting of the Georgia Academy of Science, and the Genetics Society of Georgia.
BA:  Anonymous
SO:  Bulletin of the Georgia Academy of Science. 56; 1, Pages 55-56. 1998. 
PB:  Georgia Academy of Science. Athens, GA, United States. 1998.
PY:  1998
AN:  2000-067470

Record 75 of 393 in GeoRef Disc 5: 1997-2001/10

TI:  Scapolite formation during desiccation of lower crustal shear zone rocks.
AU:  Kullerud-Kare
BK:  In: European Union of Geosciences conference abstracts; EUG 10.
BA:  Anonymous
SO:  Journal of Conference Abstracts. 4; 1, Pages 782. 1999. 
PB:  Cambridge Publications. Cambridge, United Kingdom. 1999.
PY:  1999
AN:  2000-060257

Record 76 of 393 in GeoRef Disc 5: 1997-2001/10

TI:  Pressure-temperature evolution of retrogressed kyanite eclogites, Weinschenk Island, North-East Greenland Caledonides.
AU:  Elvevold-Synnove; Gilotti-Jane-A
SO:  Lithos. 53; 2, Pages 127-147. 2000. 
FTXT:  SwetsNet (European Mirror) http://www.swetsnet.nl/link/access_db?issn=00244937&vol=00053&iss=00002&page=127 SwetsNet (US Mirror) http://www.swetsnet.com/link/access_db?issn=00244937&vol=00053&iss=00002&page=127 ScienceDirect (tm) http://www.sciencedirect.com/science?_ob=GatewayURL&_origin=SilverLinker&_urlversion=4&_method=citationSearch&_volkey=0024%2d4937%2353%23127%232&_version=1&md5=0e7af485bef7f4703eaa44418ced37f2
PB:  Elsevier. Amsterdam, International. 2000.
PY:  2000
AB:  Caledonian eclogites and associated high-pressure rocks are present in a 400X100-km long belt along the coast of North-East Greenland. Kyanite and clinozoisite eclogites on Weinschenk Island (77 degrees 54'N, 21 degrees 17'W) occur as lenses within amphibolite facies, quartzofeldspathic gneisses. The eclogites have been extensively overprinted by lower pressure assemblages and exhibit a variety of coronitic and symplectitic reaction textures that record the exhumation path of the rocks. Textural relationships and mineral composition data indicate that the initial high-pressure, plagioclase-free assemblage was garnet+omphacite + or - kyanite + or - clinozoisite+rutile. Compositional growth zoning in garnet, together with distribution of mineral inclusions within it, record a prograde evolution from epidote-amphibolite facies progressing into the eclogite facies. Post-peak pressure reaction textures include clinopyroxene-plagioclase intergrowths after omphacite; the replacement of kyanite by sapphirine-plagioclase, spinel-plagioclase and corundum-plagioclase symplectites; and resorption of garnet by amphibole-plagioclase kelyphites. The replacement textures indicate that post-eclogite facies decompression took place while the rocks remained at elevated temperatures (upper amphibolite/granulite facies conditions). The metamorphic evolution of the eclogites is in agreement with eclogite formation by thick-skinned crustal imbrication and subhorizontal shortening of the Laurentian margin during Caledonian collision, exhumation to amphibolite facies by emplacement of the eclogite-bearing thrust sheet on the Laurentian margin and accompanying erosion, and final exhumation to the surface by post-Caledonian crustal thinning.
AN:  2000-058644

Record 77 of 393 in GeoRef Disc 5: 1997-2001/10

TI:  Melting reactions of gneissic inclusions with enclosing magma at Voisey's Bay, Labrador, Canada; implications with respect to ore genesis.
AU:  Li-Chusi; Naldrett-Anthony-J
BK:  In: A special issue on Voisey's Bay Ni-Cu-Co deposit.
BA:  Naldrett-Anthony-J (editor); Li-Chusi (editor)
SO:  Economic Geology and the Bulletin of the Society of Economic Geologists. 95; 4, Pages 801-814. 2000. 
PB:  Economic Geology Publishing Company. Lancaster, PA, United States. 2000.
PY:  2000
AB:  The Voisey's Bay Ni-Cu-Co sulfide deposit is associated with a 1.333 Ga troctolitic-gabbroic intrusion, which transects the 1.85 Ga collisional boundary between Tasiuyak paragneiss of the Proterozoic-aged Churchill province to the west and orthogneiss of the Archean-aged Nain province to the east. The intrusion comprises an upper chamber to the east (the Eastern Deeps subchamber), a lower chamber to the west (the Reid Brook subchamber), and a conduit connecting them. Sulfide mineralization is closely associated with a breccia which occurs close to the basal contact of the Eastern Deeps subchamber and within the conduit. The breccia is composed of abundant Tasiuyak paragneiss inclusions with a troctolitic-gabbroic matrix. The gneiss inclusions have reacted extensively with the enclosing magma. In general, the degree of reaction increases from the Reid Brook subchamber through the conduit to the Eastern Deeps subchamber. In the course of this reaction, garnet has been oxidized to form hercynite and magnetite with the release of SiO (sub 2) to the magma; cordierite has been dehydrated to form hercynite with the release of SiO (sub 2) ; hypersthene and K feldspar have reacted together to produce hercynite with the release of SiO (sub 2) and K (sub 2) O; plagioclase has broken down to produce corundum, losing SiO (sub 2) and Na (sub 2) O to the magma and itself becoming enriched in anorthite; and the corundum has subsequently reacted with FeO and MgO from magma to form hercynite. The color of the hercynite changes progressively from beige in the Reid Brook subchamber, through green within the conduit, to black in the Eastern Deeps subchamber; this color change reflects an increase in FeAl (sub 2) O (sub 4) at the expense of the MgAl (sub 2) O (sub 4) in the hercynite. The inclusions in the Eastern Deeps subchamber characteristically show a series of reaction rims ranging from labradorite through biotite to hypersthene. It is seen that reaction with the gneiss inclusions results in the addition of SiO (sub 2) , K (sub 2) O, and Na (sub 2) O to the magma. This felsification of magma has resulted in a decrease in its ability to dissolve sulfide and therefore has promoted sulfide immiscibility.
AN:  2000-054364

Record 78 of 393 in GeoRef Disc 5: 1997-2001/10

TI:  Genesis of the Mamut porphyry copper deposit, Sabah, East Malaysia.
AU:  Imai-Akira
SO:  Resource Geology (Tokyo 1998). 50; 1, Pages 1-23. 2000. 
PB:  Society of Resource Geology. Tokyo, Japan. 2000.
PY:  2000
AB:  The Mamut deposit of Sabah, East Malaysia, is a porphury type Cu-Au deposit genetically related to a quartz monzonite ("adamellite") porphyry stock associated with upper Miocene Mount Kinabalu plutonism. The genesis of the Mamut deposit is discussed based on petrology of the intrusives in the Mount Kinabalu area combined with ore- and alteration-petrography, fluid inclusion and sulfur isotope studies. Groundmass of the adamellite porphyry at Mamut is rich in K which suggests vapor transport of alkaline elements during the mineraling magmatic process, while the groundmass of the post-ore "granodiorite" prophyry at Mamut contains small amounts of normative corundum suggesting depletion in alkaline elements at the root zone of the magma column. Subdendritic tremolitic amphibole rims on hornblende phenocrysts in the Mamut adamellite porphyry suggest interaction between the mineralizing magma and the exsolved fluids. Occurrence of clinopyroxene microphenocrysts and pseudomorphic aggregates of shredded biotite and clinopyroxene after hornblende phenocrysts in the barren intrusives imply lower water fugacity and decreasing in water fugacity, respectively. Compositional gap between the core of hornblende phenocrysts and the tremolitic amphibole rims and those in the groundmass of the Mamut adamellite porphyry suggests a decrease in pressure. Higher X (sub Mg) (= Mg/(Mg+Fe) atomic ratio) in the tremolitic aphibole rims in the Mamut adamellite porphyry compare to those of the barren intrusions suggests high oxygen fugacity. High halogen contents of igneous hydrous minerals such as amphiboles, biotite and apatite in the Mamut adamellite porphyry suggest the existence of highly saline fluids during the intrusion and solidification of the mineralizing magma. Fluid inclusions found in quartz veinlet stockworks are characterized by abundant hypersaline polyphase inclusions associated with subordinate amounts of immiscible gaseous vapor. Both Cu and Au are dispersed in disseminated and quartz stockwork ores. Chalcopyrite and pyrrhotite as well as magnetite are the principal ore minerals in the biotitized disseminated ores. Primary assemblage of intermediate solid solution (iss) and pyrrhotite converted to the present assemblage of chalcopyrite and pyrrhotite during cooling. Subsequent to biotitization, quartz veilet stockworks formed associated with retrograde chlorite alteration. The Cu-Fe sulfides associated with stockwork quartz veinlet are chalcopyrite and pyrite. Overlapping Pb and Zn and subsequent Sb mineralizations were spatially controlled by NNE-trending fractures accompamying the phyllic and advanced argillic alteration envelope. Sulfur isotopic composition of ore sulfides are homogeneous (about +2 per mil) throughout the mineralization stages. These are identical to those of the magmatic sulfides of Mount Kinabalu adamellitic rocks.
AN:  2000-054210

Record 79 of 393 in GeoRef Disc 5: 1997-2001/10

TI:  Aktsessornaya mineralizatsiya khromititov al'pinotipnykh giperbazitov Urala
Translated Title:  Accessory mineralization in chromitites of alpine-type ultrabasites in Urals.
AU:  Moloshag-V-P; Alimov-V-Yu; Anikina-Ye-V; Gulyayeva-T-Ya; Vakhrusheva-N-V; Smirnov-S-V
SO:  Zapiski Vserossiyskogo Mineralogicheskogo Obshchestva = Proceedings of the Russian Mineralogical Society. 128; 2, Pages 71-83. 1999. 
PB:  Nauka. Saint Petersburg, Russian Federation. 1999.
PY:  1999
AB:  The investigation was focused on sulfide mineralization in chromitites of the Ray-Iz, Voykar-Synin, eastern Tagil, Nuralinskiy, and Kempirsay massifs of alpine-type ultrabasites. In the scope of sulfides, two types of parageneses have been distinguished; syngenetic to chromitite formation and the type that originated during chromspinelide metamorphism. The principal part of sulfides is represented by heazlewoodite, pentlandite, bornite, and Fe-Ni monosulfide solid solutions. Godlevskite, pyrrhotite, cubanite, chalcopyrite, and PGE sulfides are also widespread. An admixture of PGE is typical for sulfides of Cu, Fe, and Ni. Specificity of the PGE geochemical spectra in chromitites is controlled by the peculiarities of their fractionation between spinelide and basalt melts in the mantle. The sulfides are associated with arsenides (orselite and maucherite), escolaite, corundum and moissanite. Compositions of the monosulfide solid solutions, syngenetic to chromites, and escolaite, corundum, and olivine allow one to apprise (independently from other methods) the temperature of the process as 900-1100 C at corresponding minimum values of the oxygen volatility 10 (super -18) -10 (super -15) bar.
AN:  2000-053214

Record 80 of 393 in GeoRef Disc 5: 1997-2001/10

TI:  Eclogite and metabasite xenoliths of subducted slab origin from the Paleogene Cedar Mountain diatremes, southwestern Wyoming, USA.
AU:  Kuehner-S-M; Irving-A-J
BK:  In: The J. B. Dawson volume; proceedings of the VIIth international kimberlite conference; Volume 1.
BA:  Gurney-J-J (editor); Gurney-J-L (editor); Pascoe-M-D (editor); Richardson-S-H (editor)
SO:  Proceedings of the International Kimberlite Conference. 7, Vol. 1; Pages 485-493. 1999. 
PB:  [publisher varies]. [location varies], United States. 1999.
PY:  1999
AB:  Lithospheric samples found as xenoliths in Paleogene diatremes and as reworked clasts and grains in conglomerates and ant mounds in the vicinity of Cedar Mountain (southwestern Wyoming) contain evidence for their derivation from variably altered mafic rocks within a subducted slab. Eclogites (including several samples containing corundum and kyanite) and epidote-amphibole-omphacite-bearing metabasites contain mineral assemblages indicative of equilibration at 450-700 degrees C at depths of 50-80 km. These temperature-pressure conditions approach, but are outside of, the diamond stability field, and suggest that the lithosphere sampled by these diatremes is unlikely to be diamondiferous. Diopside megacrysts (some with exsolved garnet) and enstatite megacrysts (some with exsolved chromite) may represent disaggregated, high temperature pegmatites related to a deep, Mg-rich alkalic magma. The diatreme matrix and associated dikes contain a disequilibrium quench mineral assemblage formed from a very low viscosity, hydrous, mafic, alkalic fluid; silicic glasses along grain boundaries within eclogite and metabasite clasts likely represent injected and reacted samples of this fluid. Low-Ti phlogopitic micas within the diatreme matrix and included within one diopside megacryst differ from micas in kimberlites, lamproites and minettes from the Wyoming Craton and elsewhere; both the mica and diopside are compositionally similar to phases in MARID xenoliths and may be related to deep metasomatic fluids.
AN:  2000-046955

Record 81 of 393 in GeoRef Disc 5: 1997-2001/10

TI:  Marundit z konglomerativ Krimu
Translated Title:  Marundite from Crimea's conglomerates.
AU:  Makarov-N-N; Marchenko-Ye-Ya; Matsyuk-S-S
SO:  Mineral'ni Resursi Ukrayini. Naukovo-Prosvitniy Zhurnal. 1999; 4, Pages 41. 1999. 
PB:  Derzhavniy Komitet Ukrayini po Geologiyi i Vykoristannyu Nadr, Derzhavnyy Informatsiyniy Geologichniy Fond Ukrayini. Kiev, Ukraine. 1999.
PY:  1999
AN:  2000-046437

Record 82 of 393 in GeoRef Disc 5: 1997-2001/10

TI:  The occurrence of preiswerkite in a tourmaline-biotite-scapolite rock from Blengsvatn, Norway.
AU:  Visser-Diederik; Nijland-Timo-G; Lieftink-Dick-J; Maijer-Cees
SO:  American Mineralogist. 84; 5-6, Pages 977-982. 1999. 
PB:  Mineralogical Society of America. Washington, DC, United States. 1999.
PY:  1999
AB:  We report paragenesis and chemistry of a new occurrence of the rare trioctahedral Al-rich sodium mica preiswerkite. The preiswerkite occurs in a tourmaline-biotite-scapolite rock in the contact zone of a gabbroic boudin surrounded by Proterozoic metasediments near the Blengsvatn, Bamble sector, southern Norway. The preiswerkite occurs as subhedral crystals or is intergrown with biotite in a polygonal fabric together with Cl-rich scapolite+tourmaline+ or -ilmenite+ or -plagioclase+ or -corundum. Accessory minerals are hematite, hogbomite, spinel, allanite, apatite, and zircon, with relic calcite. Preiswerkite has the compositional range: (Na (sub 1.84-2.02) K (sub 0.02-0.10) Ca (sub < or =0.04) ) (Mg (sub 3.13-3.42) Fe (sub 0.63-0.77) (super VI) Al (sub 1.87-2.07) ) ( (super IV) Al (sub 3.58-3.96) Si (sub 4.04-4.29) S (sub < or =0.02) )O (sub 20) [Cl (sub < or =0.03) (OH) (sub > or =3.97) ] and coexists with Na-Al-rich biotite, with the composition: (K (sub 1.38-1.61) Na (sub 0.18-0.45) Ca (sub < or =0.03) ) (Mg (sub 3.72-3.88) Fe (sub 1.38-1.43) Ti (sub 0.10-0.16) (super VI) Al (sub 0.63-0.85) ) ( (super IV) Al (sub 2.71-2.93) Si (sub 5.07-5.29) )O (sub 20) [Cl (sub 0.02) (OH) (sub > or =3.98) ]. We suggest that the assemblage preiswerkite+biotite+tourmaline+scapolite + or - ilmenite + or - plagioclase + or - corundum was formed during prograde or peak metamorphism in the area, at approximately 700 degrees C and 7 kb.
AN:  2000-046197

Record 83 of 393 in GeoRef Disc 5: 1997-2001/10

TI:  Petrology and metamorphism of sapphirine-bearing aluminous gneisses from Tonagh Island in the Napier Complex, East Antarctica.
AU:  Hokada-Tomokazu; Osanai-Yasuhito; Toyoshima-Tsuyoshi; Owada-Masaaki; Tsunogae-Toshiaki; Crowe-Warwick-A
SO:  Polar Geoscience. 12; Pages 49-70. 1999. 
PB:  National Institute of Polar Research. Tokyo, Japan. 1999.
PY:  1999
AB:  A variety of Mg-rich silica-undersaturated aluminous gneisses containing sapphirine, spinel and corundum occur within the ultrahigh-temperature (UHT) metamorphic sequence at Tonagh Island in the Napier Complex, East Antarctica. They occur as blocks or pods in quartzo-feldspathic gneisses or mafic granulite, or as thin layers around ultramafic rocks. The modes of occurrence, constituent minerals and mineral textures of these aluminous gneisses are different from each other, suggesting that they are derived from different protoliths or formation processes. Field occurrences suggest that some of the aluminous gneisses on Tonagh Island may not be simple pelitic precursors but were formed through processes associated with partial melting or metasomatism. Various reaction textures and compositional zoning in constituent minerals, which reflect retrograde metamorphism, are commonly observed in these rocks. Garnet-orthopyroxene geothermobarometry using the chemical compositions of the cores of garnet and orthopyroxene yields slightly lower temperatures (800-1000 degrees C at 0.5-1.0 GPa) than the thermal climax (1100 degrees C). Pressure condition of 0.8-1.1 GPa at the thermal peak (1030-1100 degrees C) is estimated from the garnet-orthopyroxene geobarometry.
AN:  2000-045490

Record 84 of 393 in GeoRef Disc 5: 1997-2001/10

TI:  Mineral inclusions in diamonds from the Venetia kimberlites, Northern Province, South Africa.
AU:  Viljoen-K-S; Phillips-D; Harris-J-W; Robinson-D-H
BK:  In: Proceedings of the VIIth international kimberlite conference.
BA:  Gurney-John-J (editor); Gurney-James-L (editor); Pascoe-Michelle-D (editor); Richardson-Stephen-H (editor)
SO:  Proceedings of the International Kimberlite Conference. 7, Vol. 2; Pages 888-895. 1999. 
PB:  [publisher varies]. [location varies], United States. 1999.
PY:  1999
AB:  Sulphides are the most common inclusions in diamonds from the Venetia Mine in the Northern Province, South Africa. Silicate and oxide inclusions belong predominantly to the peridotitic paragenesis, (90% of the inclusion population), with minor eclogite and websterite contributions. Peridotitic inclusions consist of chromite, garnet, olivine, and relatively rare orthopyroxene and clinopyroxene. Chromites have Cr (sub 2) O (sub 3) typically in the range 62 to 68 wt% and particularly low TiO (sub 2) (<0.5wt%). The garnets have variable calcium and chrome contents, ranging from 0.12 to 6.69 wt% for CaO and 2.51 to 19.05 wt% for Cr (sub 2) O (sub 3) . Olivines and orthopyroxenes are very magnesian, typically having Mg of 0.93 to 0.95 but with some Fe-rich members (<Fo (sub 92) , <En (sub 92) ) being present as well. Peridotitic clinopyroxenes have typical diamond inclusion compositions. Eclogitic garnets are characterised by higher calcium (up to 16.3 wt%) and very low Cr (sub 2) O (sub 3) . No inclusions exhibit the excess silica which is diagnostic of high pressure majorities. Eclogitic clinopyroxenes contain up to 0.09 wt% K (sub 2) O. The websteritic garnets have CaO contents in the range 3.5 to 5.0 wt%, but are distinguished by the relatively high Cr (sub 2) O (sub 3) of up to 0.91 wt%. Websteritic orthopyroxenes are Fe-rich (En (sub 80.2) and En (sub 80.8) ) and clinopyroxenes have up to 0.23 wt% K (sub 2) O. Unusual inclusions comprise corundum coexisting with eclogitic garnet and clinopyroxene; a chromiferous, magnesian ilmenite in contact with a peridotitic olivine; and a plagioclase associated with an iron-rich olivine. Calculated temperatures and pressures of inclusion equilibration for garnet-olivine, garnet-orthopyroxene, garnet-clino-pyroxene and orthopyroxene-clinopyroxene pairs range from approximately 900 to 1400 degrees C and 55 to 70 kb. Diamonds from the Venetia Mine are considered to have crystallised in a thick, ancient cratonic root which consists predominantly of very depleted, highly magnesian peridotite mantle and which encloses minor eclogite and websterite veins or lenses.
AN:  2000-043951

Record 85 of 393 in GeoRef Disc 5: 1997-2001/10

TI:  Presolar corundum and spinel from the Bishunpur and Semarkona ordinary chondrites.
AU:  Choi-B-G; Huss-Gary-R; Wasserburg-G-J
BK:  In: Abstracts of papers submitted to the Twenty-ninth lunar and planetary science conference.
BA:  Anonymous
SO:  Abstracts of Papers Submitted to the Lunar and Planetary Science Conference. 29; 1998. 
PB:  Lunar and Planetary Science Conference. Houston, TX, United States. 1998.
PY:  1998
AN:  2000-043287

Record 86 of 393 in GeoRef Disc 5: 1997-2001/10

TI:  Plagioclase replacement textures in partially eclogitized gabbros from the Sanddal mafic-ultramafic complex, North-East Greenland eclogite province.
AU:  Lang-Helen-M; Gilotti-Jane-A
BK:  In: Geological Society of America, 1999 annual meeting.
BA:  Anonymous
SO:  Abstracts with Programs - Geological Society of America. 31; 7, Pages 167-168. 1999. 
PB:  Geological Society of America (GSA). Boulder, CO, United States. 1999.
PY:  1999
AB:  The North-East Greenland Eclogite Province (NEGEP) contains widespread outcrops of eclogite and related high pressure rocks with a Caledonian metamorphic age (Brueckner, et al., 1998, Contrib. Mineral. Petrol., 130, 103-120). In addition to the true eclogites, there are many mafic and ultramafic bodies enclosed in the dominant quartzo-feldspathic gneisses that are partially eclogitized and have experienced varying degrees of retrogression to amphibolite facies assemblages.In the northwest corner of Sanddal (78 degrees 05'N, 21 degrees 30'W), a cluster of variably eclogitized mafic and ultramafic bodies (the Sanddal Mafic-Ultramafic Complex, SMUK) was sampled extensively. Partially eclogitized gabbroic rocks from SMUK exhibit a wide range in development of eclogite facies mineral assemblages. Except for plagioclase, relict igneous minerals (olivine, orthopyroxene, clinopyroxene, biotite and spinel) show systematic replacement textures that vary little from sample to sample. Plagioclase domains, which display the widest variety of different textures and minerals, can be placed in a roughly progressive sequence that provides insight into the eclogite-forming process. In the least eclogitized gabbro, plagioclase was initially replaced by an omphacite-spinel symplectite. Locally, garnet nucleated (on spinel?) and the omphacite-spinel symplectite was abruptly replaced by fine, granular garnet in contact with minor omphacite and amphibole. In other samples, where more plagioclase was present and eclogitization was further progressed, plagioclase domains are typically coronitic with an outer rim of garnet surrounding a layer of omphacitic pyroxene with corundum, clinozoisite and/or kyanite inclusions around a core of inclusion-rich relict plagioclase. Garnet eventually engulfs the plagioclase domains and omphacite is preserved only as inclusions in garnet. In the most thoroughly recrystallized sample, a garnet hornblende clinopyroxenite, plagioclase is rare and sodium is distributed in clinopyroxene (Jd18) and amphibole.
AN:  2000-037763

Record 87 of 393 in GeoRef Disc 5: 1997-2001/10

TI:  Upper-mantle system olivine-clinopyroxene-corundum-coesite; melting relations, magma generation and differentiation.
AU:  Litvin-Yu-A
BK:  In: 30th international geological congress; abstracts.
BA:  Anonymous
SO:  International Geological Congress, Abstracts = Congres Geologique International, Resumes. 30, VOL.2; Pages 437. 1996. 
PB:  [International Geological Congress]. [location varies], International. 1996.
PY:  1996
AN:  2000-037212

Record 88 of 393 in GeoRef Disc 5: 1997-2001/10

TI:  The Sondalo gabbroic complex and its country rocks; new geological and petrological data.
AU:  Giacomini-Folco; Messiga-B; Tribuzio-R; Braga-R
BK:  In: 4th workshop on Alpine geological studies.
BA:  Szekely-Balazs (editor); Dunkl-Istvan (editor); Kuhlemann-Joachim (editor); Frisch-Wolfgang (editor)
SO:  Tuebinger Geowissenschaftliche Arbeiten. Reihe A, Geologie, Palaeontologie, Stratigraphie. 52; Pages 156. 1999. 
PB:  Institut und Museum fuer Geologie und Palaeontologie. Tubingen, Federal Republic of Germany. 1999.
PY:  1999
AB:  In the upper Austro-Alpine System of the Central Alps the Sondalo gabbroic complex is a stock of intrusive rocks into the polymetamorphic basement of the Languard-Campo nappe. The complex consists in an inner portion of gabbro-norites with minor olivine-bearing gabbros showing poikilitic red-brown titan-pargasite; the outer portion is mostly composed of dioritic rocks. The enclosing country rocks are sillimanite+biotite+garnet-bearing paragneisses, orthogneisses, amphibolites and rare marble layers. Basement xenoliths occur within the gabbroic complex. Geochemical and isotopic data suggest that the gabbro-norites and the olivine-bearing gabbros formed by concomitant fractional crystallization and crustal assimilation of tholeiitic melts. Sm/Nd and Rb/Sr geochronological determination indicate an age of intrusion of 300-290 Ma. The country rocks show a regional metamorphic overprint under high-grade amphibolite-facies condition. Granulite-facies assemblages are locally present in paragneisses (sillimanite+orthopyroxene+K-feldspar parageneses). Thermobarometric estimates were performed on paragneisses and amphibolites giving values of 610-750 degrees C and about 5 kbar. At the contact with the gabbroic complex, the country rocks show the development of variable amounts of Al-rich minerals, such as garnet, cordierite, spinel, corundum and staurolite. Intrusive rocks of dioritic composition show the overgrowth of poikilitic garnet and orthorombic amphibole after igneous biotite and orthopyroxene; the modal amount of garnet increases towards the gabbroic complex. Xenolithic rocks within the gabbroic complex contain locally corundum and spinel in high modal amounts (up to 70% by volume), and they are interpreted as the refractory residuum of metapelitic material, related to the assimilation process. The Sondalo gabbroic complex can be considered a post-Variscan gabbro that underwent a substantial assimilation of country rocks during its emplacement in a metamorphic basement characterized by a high-temperature/low-pressure regional metamorphism.
AN:  2000-030730

Record 89 of 393 in GeoRef Disc 5: 1997-2001/10

TI:  Sapphires from Czech Republic and their origin.
AU:  Malikova-Petra; Zacharia-Jioi
BK:  In: Proceedings of the XIVth European current research on fluid inclusions.
BA:  Boiron-Marie-Christine (editor); Pironon-Jacques (editor)
SO:  Proceedings of the ... European Current Research on Fluid Inclusions (ECROFI). 14; Pages 190-191. 1997. 
PB:  International. 1997.
PY:  1997
AN:  2000-023240

Record 90 of 393 in GeoRef Disc 5: 1997-2001/10

TI:  The genesis of corundum megacrysts related to alkali basalt in Hainan.
AU:  Qiu-Zhili; Qin-Shecai; Pang-Xuebin
SO:  Zhongshan Daxue Xuebao = Acta Scientiarum Naturalium Universitatis Sunyatseni. 34; 3, Pages 95-101. 1995. 
PB:  Zhongshan University. Guangzhou, China. 1995.
PY:  1995
AN:  2000-013496

Record 91 of 393 in GeoRef Disc 5: 1997-2001/10

TI:  Electron microscope and infrared spectral studies on the structure of alumina phases.
AU:  Kimura-Seiji; Kamei-Kazuhiko; Tsuda-Noritoshi; Saito-Yoshio; Koike-Chiyoe; Kaito-Chihiro
BK:  In: Antarctic meteorites XX; papers presented to the twentieth symposium on Antarctic meteorites.
BA:  Anonymous
SO:  Papers Presented to the ... Symposium on Antarctic Meteorites. 20; Pages 111-114. 1995. 
PB:  National Institute of Polar Research. Tokyo, Japan. 1995.
PY:  1995
AN:  2000-012375

Record 92 of 393 in GeoRef Disc 5: 1997-2001/10

TI:  Les Clinopyroxenites a grenat-corindon du massif ultrabasique de Ronda (Espagne); etude geochimique preliminaire
Translated Title:  Garnet-corundum-bearing clinopyroxenites of Ronda ultramafic massif, Spain; preliminary geochemical study.
AU:  Piboule-M; Gueddari-K
BK:  In: 16>eme) reunion des sciences de la terre; Dynamique et economie Dynamique et economie de la Terre
Translated Title:  16th Earth sciences meeting; Dynamics and economy of the Earth.
BA:  Anonymous
SO:  Reunion Annuelle des Sciences de la Terre. 16; Pages 80. 1996. 
PB:  Societe Geologique de France. Paris, France. 1996.
PY:  1996
AN:  2000-002847

Record 93 of 393 in GeoRef Disc 5: 1997-2001/10

TI:  Are ureilites residues from partial melting of chondritic material? The answer from MAGPOX.
AU:  Goodrich-Cyrena-Anne
SO:  Meteoritics and Planetary Science. 34; 1, Pages 109-119. 1999. 
PB:  Meteoritical Society. Fayetteville, AR, United States. 1999.
PY:  1999
AB:  Calculations performed using MAGPOX show that no bulk compositions having chondritic Ca/Al ratio and within the range of chondritic Si/Mg ratios can produce the olivine-pigeonite ureilites (which constitute 65% of those for which modal abundances are known) as residues of single-stage equilibrium partial melting. Calcium/aluminum ratios of 2-3.5XCI are required. In addition, all the ureilites could not have formed from a single composition at various degrees of reduction, because they show no correlation between pigeonite/olivine ratio and mg ratio. Materials with various Al/Mg ratios, ranging from subchondritic to superchondritic, are required. If these materials are primitive (i.e., created by nebular processes rather than planetary igneous processes), they are unknown in the meteorite record. Excess accretion (relative to chondrites) of 5-10 mol% of a high-temperature condensate component, which was itself almost completely depleted in corundum due to early fractionation, could create the necessary compositions. The plausibility that such processes occurred on a parent-body sized scale is difficult to assess. In contrast, lodranites can be produced as residues of approximately 3-30% equilibrium partial melting of an average ordinary chondritic composition at the appropriate level of reduction. Although many features of ureilites suggest that they are relatively primitive residues produced by low degrees of melting of chondritic materials, and thus resemble lodranites and other groups of primitive achondrites, their predominantly pigeonite + olivine mineralogy remains difficult to explain within this simple scenario.
AN:  1999-029489

Record 94 of 393 in GeoRef Disc 5: 1997-2001/10

TI:  Exotic origin of the ruby deposits of the Mangari area in SE Kenya.
AU:  Mercier-A; Debat-P; Saul-John-M
SO:  Ore Geology Reviews. 14; 2, Pages 83-104. 1999. 
FTXT:  ScienceDirect (tm) http://www.sciencedirect.com/science?_ob=GatewayURL&_origin=SilverLinker&_urlversion=4&_method=citationSearch&_volkey=0169%2d1368%2314%2383%232&_version=1&md5=e35208a2a6697588ae115b357f12b724
PB:  Elsevier. Amsterdam, International. 1999.
PY:  1999
AB:  The Proterozoic Mozambique Belt contains numerous primary deposits of gem-corundum (i.e., ruby and sapphire). The ruby deposits in the Mangari area of SE Kenya, are among the most productive and best known. Enclosed within a metasedimentary sequence dominated by sillimanite-graphitic gneisses, the Mangari deposits are associated with rootless ultrabasic bodies. Ruby occurs (1) in lenses on the inner side of the contacts between the ultrabasites and the surrounding metasediments and (2) in veins within the ultrabasic bodies or forming their margins. Field relationships reveal that the corundum-bearing rocks are genetically related to the ultrabasic bodies but not to the surrounding gneisses. Laboratory studies and petrographic comparisons indicate that the ruby-bearing rocks crystallized under granulite facies conditions of 700-750 degrees C and 8-10.5 kbar. By contrast, the surrounding gneisses show only amphibolite facies metamorphism with maximum temperatures around 650 degrees C and pressures which did not exceed 7 kbar. At Mangari, the ruby-bearing rocks, as their associated ultrabasites, appear to be exotic with respect to the surrounding metasedimentary rocks. We interpret them as fragments of a deeper crust brought up to their present-day exposure level by the ultrabasic bodies during their emplacement as thrust sheets. Similar reasoning may account for the presence of charnockitic gneisses nearby. By contrast, granulite facies metamorphism characterizes all rock types genetically relatable to the Tanzanian ruby deposits at Longido and Lossogonoi, both also situated in the Mozambique Belt. This suggests that, if associated with ultrabasites, primary deposits of rubies (and of subgem red corundum) formed only under granulite facies conditions in the Mozambique Belt. Some of these deposits were subsequently tectonically inserted into country rocks of lower metamorphic grade. This apparently occurred without the total fracturing of all crystalline gems.
AN:  1999-046605

Record 95 of 393 in GeoRef Disc 5: 1997-2001/10

BK:  Mineralogie et petrologie du pluton de Cawood Low, Quebec
Translated Title:  Mineralogy and petrology of the Cawood Pluton, Low, Quebec.
BA:  Paris-Mireille
PY:  1999
DG:  Bachelor's
DI:  University of Ottawa. Ottawa, ON, Canada. Pages: 60. 1999.
AB:  Situated in the municipality of Low Townships, approximately sixty-five kilometers northeast of Ottawa, the Cawood pluton is made up of relatively homogeneous nepheline syenite with some alkali-feldspar syenite without nepheline. This Precambrian intrusion cuts the metamorphic lithologies of the Grenville Province and is part of a suite of alkaline intrusions that extends about eight hundred kilometers from eastern Ontario near Blue Mountain (Bancroft), to western Quebec near Albanel Lake (about two hundred kilometers northwest of Chibougamau). The rocks are remarkably fresh and free of alteration. They are medium to coarse-grained syenites with a slight foliation defined by the alignment of mafic minerals. These minerals are mostly amphibole and garnet, both iron-rich. Biotite is also found in certain places and is also very iron-rich. Potassic feldspar, identified as microcline by X-ray diffraction, is moderately ordered and perthitic. The nepheline is relatively fresh in thin section although its preferred dissolution on weathered surfaces leaves many small millimetric cavities. Accessory minerals are mostly calcite, zircon, apatite, magnetite, sodalite and pyrite. The geochemistry of the Cawood pluton is typical of anorogenic alkaline intrusions. The rocks demonstrate high enrichments in iron, sodium and potassium. Normative nepheline is very high, from 6 to 33%, and no normative corundum has been observed. Finally, the pluton's geochemistry and mineralogy is typical of the alkaline intrusions associated with rift zones in continental environments.
AN:  1999-069711

Record 96 of 393 in GeoRef Disc 5: 1997-2001/10

TI:  A corundum-quartz assemblage from the Eastern Ghats granulite belt, India; evidence for high P-T metamorphism?.
AU:  Shaw-R-K; Arima-M
SO:  Journal of Metamorphic Geology. 16; 2, Pages 189-196. 1998. 
PB:  Blackwell. Oxford, United Kingdom. 1998.
PY:  1998
AN:  1998-024242

Record 97 of 393 in GeoRef Disc 5: 1997-2001/10

TI:  Viscosity data for hydrous peraluminous granitic melts; comparison with a metaluminous model.
AU:  Dingwell-D-B; Hess-K-U; Romano-C
SO:  American Mineralogist. 83; 3-4, Pages 236-239. 1998. 
PB:  Mineralogical Society of America. Washington, DC, United States. 1998.
PY:  1998
AB:  We performed 27 viscosity determinations on dry and water-bearing peraluminous haplogranitic melts. The dry melt compositions cover the range of normative corundum to be expected in peraluminous granitic melts in nature. The compositions are based on addition of Al (sub 2) O (sub 3) to a haplogranitic melt (HPG8) whose composition is near that of the projection of the 2 kbar H (sub 2) O-saturated minimum melt composition into the system NaAlSi (sub 3) O (sub 8) -KAlSi (sub 3) O (sub 8) -SiO (sub 2) . The H (sub 2) O contents of the hydrous melts were analyzed using Karl Fischer titration ranging from 1 to 3 wt%. The viscosity determinations were performed using a modified micropenetration method in the viscosity range of 10 (super 10) to 10 (super 11) Pa-s, at 1 atm pressure, and in the temperature ranges of 880-940 degrees C and 470-640 degrees C for the dry and wet melts, respectively. For the dry peraluminous melts in this high viscosity range, addition of the first few percent of normative corundum to a metaluminous granitic melt increases the viscosity, which remains nearly constant despite further addition of Al (sub 2) O (sub 3) . Thus a viscosity maximum is inferred for dry slightly peraluminous granitic melts. The hydrous melt viscosity data were compared with the recent calculational model of Hess and Dingwell (1996), which was based on and designed for metaluminous melt viscosities. That model is capable of describing the viscosities of hydrous peraluminous granitic melts within the uncertainties stated for its application in metaluminous melts.
AN:  1998-031609

Record 98 of 393 in GeoRef Disc 5: 1997-2001/10

TI:  Corundum-bearing residues produced through the evaporation of natural and synthetic hibonite.
AU:  Floss-Christine; El-Goresy-Ahmed; Zinner-Ernst; Palme-Herbert; Weckwerth-Gerd; Rammensee-Werner
SO:  Meteoritics and Planetary Science. 33; 2, Pages 191-206. 1998. 
PB:  Meteoritical Society. Fayetteville, AR, United States. 1998.
PY:  1998
AN:  1998-031662

Record 99 of 393 in GeoRef Disc 5: 1997-2001/10

TI:  Peraluminous sapphirine formed during retrogression of a kyanite-bearing eclogite from Pays de Leon, Armorican Massif, France.
AU:  Godard-Gaston; Mabit-Jean-Luc
SO:  Lithos. 43; 1, Pages 15-29. 1998. 
FTXT:  ScienceDirect (tm) http://www.sciencedirect.com/science?_ob=GatewayURL&_origin=SilverLinker&_urlversion=4&_method=citationSearch&_volkey=0024%2d4937%2343%2315%231&_version=1&md5=0473d48eda15da34de926884e99816ab
PB:  Elsevier. Amsterdam, International. 1998.
PY:  1998
AB:  In a quartz-free eclogite from Pays de Leon (Armorican Massif, France) kyanite has been replaced by a symplectite of plagioclase, corundum, spinel and sapphirine. The sapphirine is amongst the most aluminous yet reported in the literature. One analysis (Mg (sub 1.38) Fe (sub 0.17) (super 2+) Fe (sub 0.05) (super 3+) Cr (sub 0.01) Al (sub 2.37) (super VI) Al (sub 2.43) (super IV) Si (sub 0.57 ) O (sub 10) ) shows the highest degree of Tschermak's substitution (Si (sub -1) Mg (sub -1) Al (super IV) Al (super VI) ) yet reported for sapphirine. Omphacite has been completely transformed into clinopyroxene+plagioclase symplectite. A quantification of material transfer indicates that kyanite and omphacite breakdowns were coupled. The kyanite and omphacite pseudomorphs exchanged components during their formation but the two pseudomorphs together behaved as a more-or-less closed system. The kyanite symplectitisation is the source of the silica required for the omphacite breakdown (i.e., jadeite (sub ss) +SiO (sub 2) -->albite (sub ss) ). The kyanite and omphacite pseudomorphs display all the characteristics of a metasomatic system at a microscopic scale (zonation, diffusion fronts, etc.). These features are explained in terms of relative mobility of the chemical components. The kyanite and omphacite pseudomorphs give information about the P-T path of the Leon eclogites during retrograde metamorphism. The appearance of sapphirine after kyanite is attributed to a low-pressure and high-temperature evolution from eclogite-facies to granulite-facies conditions. copyright 1998 Elsevier Science B.V.
AN:  1998-039862

Record 100 of 393 in GeoRef Disc 5: 1997-2001/10

TI:  A corundum-quartz assemblage in altered volcanic rocks Bond Range, Tasmania.
AU:  Bottrill-R-S
SO:  Mineralogical Magazine. 62; 3, Pages 325-332. 1998. 
FTXT:  Catchword http://www.catchword.com/cgi-bin/cgi?body=linker&reqidx=0026-461x()62:03L.325 EBSCO Online http://www.ebsco.com/online/direct.asp?ArticleID=HBCKT2BBU3X9Q10504FN
PB:  Mineralogical Society. London, United Kingdom. 1998.
PY:  1998
AN:  1998-047148

Record 101 of 393 in GeoRef Disc 5: 1997-2001/10

TI:  Finding of corundum-bearing gabbro boulder possibly derived from the Horoman peridotite complex, Hokkaido, northern Japan.
AU:  Morishita-Tomoaki; Kodera-Tadahiro
SO:  Ganko = Journal of Mineralogy, Petrology and Economic Geology. 93; 2, Pages 52-63. 1998. 
PB:  Nippon Ganseki Kobutsu Kosho Gakkai, c/o: Tohoku Daigaku Rigakubu. Sendai, Japan. 1998.
PY:  1998
AB:  Coarse-grained corundum-bearing gabbro was found as a boulder in the Ponsanushibetsu river of the Samani Town, Hokkaido, Japan. Its provenance is most probably the GBII gabbro (Shiotani and Niida, 1997) of the Horoman peridotite complex on the basis of mineral assemblage and chemical composition. Deduced from textural relationships between corundum and other minerals, corundum has not been stable in the gabbro under the latest metamorphic condition. The reaction for the corundum breakdown is possibly shown as: corundum+clinopyroxene = spinel+plagioclase (i). This reaction suggests that the GBII protolith had experienced heating or decompression or both to cause the corundum breakdown. On the other hand, we can estimate two possible reactions for corundum formation. First, corundum can be formed by a reaction (i) during cooling or compression after the formation of spinel by a reaction, which is shown as: olivine+anorthite = orthopyroxene+clinopyroxene+spinel (ii), in relatively aluminous protoliths (e.g., plagioclase-rich protoliths). Second, formation of corundum at much higher pressures is also possible by a reaction: Ca-tschermaks in clinopyroxene = corundum+grossular (iii). This reaction means that corundum-bearing garnet-clinopyroxenite can be formed from aluminous clinopyroxenite at high-pressure. The recent interpretation of the Horoman peridotite complex as a mantle diapir ascended from the garnet stability field (Ozawa and Takahashi, 1995) may favor the latter process, the high-pressure origin of the corundum. The GBII gabbro possibly ascended as one of the member of the mantle diapir after it had been metamorphosed under high P-T conditions to form corundum as one of high-pressure minerals.
AN:  1998-049810

Record 102 of 393 in GeoRef Disc 5: 1997-2001/10

TI:  Oxygen, magnesium, calcium, and titanium isotopes in asymptotic giant branch and supernova oxides.
AU:  Choi-B-G; Huss-G-R; Wasserburg-G-J
BK:  In: 61st Meteoritical Society meeting; abstracts.
BA:  Anonymous
SO:  Meteoritics and Planetary Science. 33; 4, Suppl., Pages A32. 1998. 
PB:  Meteoritical Society. Fayetteville, AR, United States. 1998.
PY:  1998
AN:  1998-067167

Record 103 of 393 in GeoRef Disc 5: 1997-2001/10

TI:  Enclaves in the Rochovce granite intrusion as indicators of the temperature and origin of the magma.
AU:  Hrasko-L-ubomir; Kotov-Alexander-B-(Kotov-Aleksandr-B); Salnikova-Ekatherina-B-(Salnikova-Ekaterina-B); Kovach-Viktor-P
SO:  Geologica Carpathica. 49; 2, Pages 125-138. 1998. 
PB:  Slovak Academic Press Ltd.. Bratislava, Slovak Republic. 1998.
PY:  1998
AB:  Two boreholes in the Mo-W-bearing porphyric Cretaceous granite, located near the village of Rochovce, Western Carpathians, reveal the existence of two types of enclaves: 1. micaceous enclaves (biotite-plagioclase gneisses without quartz, with highly calcitic plagioclases) and 2. mafic microgranular enclaves (MME), with predominantly dioritic composition. In the first type, corundum, Zn-hercynite and magnetite were produced due to the high temperature melting of biotite. These are considered to be restites. The melting reactions in biotite indicate that the granite magma temperatures exceeded 800 degrees C at the time of the enclave melting. The mafic microgranular enclaves represent portions of mafic magma incorporated in the granitic magma. Seven types of mineralogical-petrological indicators of magma mixing were found. The chemical and Sm/Nd isotopic characteristics of the host granite and MME show that chemical and isotopic equilibration was achieved within the granite-MME system. The initial epsilon Nd value in granite (-3.0) indicates that some mafic magmatic material was added to the magma chamber. The apparent crustal residence age (T (super *) (sub DM) = 1100 Ma) indicates an old, Precambrian history of the crustal source material. Thus, the Rochovce magma was derived from a crustal source, with addition of more mafic (probably mantle-derived) magma.
AN:  1998-073200

Record 104 of 393 in GeoRef Disc 5: 1997-2001/10

TI:  Effect of Al and organic acids on the surface chemistry of kaolinite.
AU:  Ward-David-B; Brady-Patrick-V
SO:  Clays and Clay Minerals. 46; 4, Pages 453-465. 1998. 
PB:  Clay Minerals Society. Clarkson, NY, United States. 1998.
PY:  1998
AB:  The cause of pH and ionic strength-dependent proton and hydroxyl adsorption onto kaolinite is specific binding at edge Al and Si sites, and it can be modeled as a function of temperature with a triple layer model (TLM) of the mineral-solution interface. Exchange of Al for protons and hydroxyls is observed at low pH, with a stoichiometry approaching 1:3 (Al:H (super +) ). Adsorption of organic acids from dilute solutions depends on: 1) solution pH; 2) the functionality of the acid; and, to a lesser extent, 3) temperature. Such adsorption may occur primarily at Al sites exposed on kaolinite edges, as indicated by sorption experiments on the constituent oxides, where negligible sorption was observed on SiO (sub 2) (quartz), but was significant on Al (sub 2) O (sub 3) (corundum) surfaces. Under similar conditions, oxalate adsorbs more strongly than acetate or formate to aluminol sites.
AN:  1999-003453

Record 105 of 393 in GeoRef Disc 5: 1997-2001/10

TI:  Presolar corundum and spinel in ordinary chondrites; origins from AGB stars and a supernova.
AU:  Choi-Byeon-Gak; Huss-Gary-R; Wasserburg-G-J; Gallino-Roberto
SO:  Science. 282; 5392, Pages 1284-1289. 1998. 
FTXT:  Journals@OVID http://gateway.ovid.com/ovidweb.cgi?T=JS&PAGE=fulltext&D=ovft&NEWS=n&DBC=n&AN=00007529-199811130-00003 Science http://www.sciencemag.org/cgi/content/full/282/5392/1284 HighWire http://www.sciencemag.org/cgi/content/full/282/5392/1284
PB:  American Association for the Advancement of Science. Washington, DC, United States. 1998.
PY:  1998
AN:  1999-003478

Record 106 of 393 in GeoRef Disc 5: 1997-2001/10

BK:  Metamorphic evolution of the Buck Creek mafic-ultramafic complex, Clay County, North Carolina, USA.
BA:  Emilio-Michael-Charles
PY:  1998
DG:  Master's
DI:  University of South Florida, Tampa. Tampa, FL, United States. 1998.
AB:  The Buck Creek mafic-ultramafic complex (BCUC) is one of a series of ultramafic bodies located in the high-grade metamorphic belt of the Blue Ridge Mountains. Models for the igneous and tectonic origins of the complex are dependent on its metamorphic record and the history of the P-T-P (sub H2O) changes recorded in its mineral assemblages. BCUC rocks are well suited to such studies as they include a range of lithologies: troctolite, edenite-margarite schist, amphibolite, chlorite talc schists, and dunite; which preserve both anhydrous and hydrous metamorphic assemblages over a range of grades and protoliths. Assemblage and P-T data from the troctolite-edenite-margarite schist interlayers in BCUC suggests granulite facies peak metamorphic conditions for the unit. The assemblage orthopyroxene + clinopyroxene/spinel (+ or -sapphirine+ or -amphibole) coronal symplectite in the troctolites indicates hot dry metamorphism (Tenthorey et al, 1996). The adjacent edenite-margarite schists contain an equilibrium assemblage of edenitic amphibole+anorthite+ or -corundum+ or -zoisite+ or -kyanite with retrograde margarite. This assemblage places new barometric constraints on peak metamorphism of the BCUC of >11 kbars (up to 14 kbars) at 825 degrees C. Similarities between peak and retrograde conditions at Buck Creek and the Lake Chatuge mafic-ultramafic complex; and to surrounding supracrustal rocks of the Tallulah Falls Formation at suggests that these areas experienced the same metamorphic history. All of these units may have been part of the same crustal block as early as the onset of the Taconic orogeny. BCUC rocks in the southern and western portions of the unit record evidence for a second, middle amphibolite grade metamorphic. Thermobarometry along with textural relationships in hydrated mineral assemblages from type II amphibolites (McElhaney & McSween, 1983), dunites, chlorite-talc schists, and EMS all record temperatures of approximately 525 degrees C and pressures of 4-6 kbars. The conditions of this second event are similar to those of formation of the Chunky Gal Thrust (550-600 degrees C and 4-6 kbars (Krukoski & Moecher, 1998), which forms part of the western margin of the complex.
AN:  1999-022164

Record 107 of 393 in GeoRef Disc 5: 1997-2001/10

TI:  The sapphirine-bearing rocks of the Fiskenaesset region, West Greenland; geological setting, controls on their formation and record of crustal evolution.
AU:  Herd-Richard-K; Windley-Brian-F
BK:  In: Geological Society of America, 1998 annual meeting.
BA:  Anonymous
SO:  Abstracts with Programs - Geological Society of America. 30; 7, Pages 380. 1998. 
PB:  Geological Society of America (GSA). Boulder, CO, United States. 1998.
PY:  1998
AB:  Sapphirine occurs at over 80 localities in the Fiskenaesset area of West Greenland, including the type locality, in rocks with complicated mineralogical and textural associations. Over 50 mineral phases have been recognized. Generally excellent exposures in this early Archaean terrane provide a unique background for understanding the mode of occurrence of these rocks. Our detailed mapping and study combined with published data demonstrate the following 6 controls on sapphirine formation: 1) Occurrences are on the upper contact of the Fiskenaesset anorthosite complex with overlying metavolcanic amphibolites; 2) Magnesian spinel-bearing ultramafic rocks, calc-silicate rocks, and aluminous meta-pelitic schists were important protoliths; 3) Stable isotope data indicate that alteration by sea-water of mafic-ultramafic rocks created serpentine protolith material; 4) Emplacement of the complex along the altered protolith interface deep in the oceanic crust introduced plagioclase- and chromite-bearing hydrous magmatic material, resulting in chromiferous phases and relatively Ca-rich metasomatic assemblages next to anorthosite; 5) Thrusting and crustal thickening transported the rocks into the deep continental crust, where they underwent granulite facies metamorphism leading to formation of enstatite, olivine, spinel, and hornblende; 6) Retrogression under amphibolite facies conditions was associated with introduction of hydrous granitic melts, mainly silica and potassium feldspar, leading to formation of abundant phlogopite relative to all other Fe-Mg silicates, sapphirine from spinel, and corundum including ruby. Associated granitic pegmatites were emplaced during formation of second phase isoclines. Thus maximum sapphirine development occurs regionally in areas retrogressed from granulite to amphibolite grade, and where introduction of granitic melts has taken place. Magnesian spinel layers and refractory sapphirine+ or -spinel+ or -corundum associations persisted during changing P-T-X conditions. A petrogenetic flow chart satisfactorily explains the origin of the sapphirine-bearing and associated rocks in terms of these controls.
AN:  1999-026286

Record 108 of 393 in GeoRef Disc 5: 1997-2001/10

BK:  Geology and petrogenesis of the Ireteba Pluton; implications for the generation of peraluminous granites.
BA:  D-Andrea-Jessica-L
PB:  Pages: 104. 1998.
PY:  1998
DG:  Master's
DI:  Vanderbilt University. Nashville, TN, United States.
AB:  The Late Cretaceous Ireteba granite is strongly peraluminous with 1-2% normative corundum, and 2-micas+ or -garnet. It is unusual in its extensive interactions with mafic magma, a relationship that has not been widely documented for peraluminous granites. Nd and Sr isotopic ratios, as well as ancient (1.7-2.5 Ga) zircon cores, demonstrate a large crustal component in the source. High Sr concentrations (400-700 ppm) and low heavy rare earth elements ( approximately 2x chondrite) imply a feldspar poor, garnet rich residue, consistent with the source being deep crust. However, Ireteba isotopes do not closely match regional crustal isotopic values, which are reflective of Early Proterozoic, metamorphosed granitic and supracrustal rocks of the Mojave terrane. Based on isotopes and mixing models, it appears that the Ireteba granite is a hybrid. There are two possible hybridization scenarios: (1) Hybridization occurred at depth by juvenile mafic magma in the Late Cretaceous. This scenario is consistent with mingling and mixing between the mafic magma and peraluminous granitic magma of the pluton, and (2) Hybridization by mafic magma occurred during an earlier episode and this prehybridized crust melted to form the Ireteba granite. A second population of inherited Jurassic zircon cores support this scenario, putting hybridization in the Jurassic. In either case, the Ireteba pluton demonstrates the lack of purity of some "pure" crustal melts (eg. peraluminous granites with crustal isotopic signatures), and may suggest that mafic magma can play a more important role in the generation of peraluminous granites than is commonly thought.
AN:  1999-035072

Record 109 of 393 in GeoRef Disc 5: 1997-2001/10

TI:  The origin of garnetiferous mylonitic gneisses in chill margins of the Hyde School Gneiss, NW Adirondacks, NY.
AU:  Hudson-Michael-R; Dahl-Peter-S
BK:  In: Geological Society of America, 1998 annual meeting.
BA:  Anonymous
SO:  Abstracts with Programs - Geological Society of America. 30; 7, Pages 280-281. 1998. 
PB:  Geological Society of America (GSA). Boulder, CO, United States. 1998.
PY:  1998
AB:  Chemical analyses and fabric characteristics of mylonitic gneisses that occur at the margins of Hyde School Gneiss (HSG) bodies in the NW Adirondack Lowlands are consistent with an interpretation that these mylonites are highly deformed chill margins of the HSG and provide new evidence that the HSG is a metaintrusive (Buddington, 1939 and McLelland et al., 1992) rather than a metavolcanic (deLorraine and Sangster, 1997). The HSG (ca. 1170 Ma) consists of a suite of rocks that range from alkali-granite to diorite (regionally metamorphosed to approximately 650 degrees C) that outcrop as 14 domical shaped bodies dispersed throughout the Lowlands, always in contact with marble. Enigmatic, anhydrous garnet-sillimanite and garnet-clinopyroxene mylonitic gneisses occur around the margins of nearly every HSG and have been interpreted in radically different ways. With the exception of some Ca and Fe enrichment and Na and Sr depletion, all other major elements and Rb, Zr, Ba, Y, P, and the REE demonstrate that these rocks are chemically indistinguishable from low silica-bearing HSG rocks and that their compositions follow trends that suggest a magmatic differentiation origin for the entire HSG suite. Almandine garnets (1-5 cm in dia.) constitute 10 to 40 vol. % of the rock and are enriched in Ca (up to 20% grossular). Many contain complex inclusion trails which show evidence of early rotation, static overgrowth, and subsequent rotation. Overgrowths may have concentric graphite inclusions, are sometimes associated with spinel-bearing symplectites + or - cordierite + or - corundum, have yielded garnet-biotite temperatures >800 degrees C, and have zoning profiles consistent with growth during a temperature increase and pressure decrease. Garnet rims in the garnet-sillimanite gneisses yield garnet-biotite temperature of approximately 680 degrees C and matrix fibrolite/sillimanite anastomose these porphyroblasts. Both garnet and sillimanite are the product of syntectonic, dehydration reactions involving plagioclase and biotite. These observations suggest that initial garnet growth was accompanied by forceful emplacement, followed by a reduction in pressure during subsequent heating and growth, followed by syn-tectonic, metamorphic overgrowth. Since slivers of marble are interleaved with marginal mylonites at some exposures, assimilation of carbonate country rock is proposed as the mechanism for some changes in bulk chemistry of the chill margin and abundant graphite.
AN:  1999-039565

Record 110 of 393 in GeoRef Disc 5: 1997-2001/10

TI:  P-T history and structural controls on the Buck Creek mafic-ultramafic complex, eastern Blue Ridge, North Carolina.
AU:  Emilio-M; Ryan-J
BK:  In: Geological Society of America, 1998 annual meeting.
BA:  Anonymous
SO:  Abstracts with Programs - Geological Society of America. 30; 7, Pages 380. 1998. 
PB:  Geological Society of America (GSA). Boulder, CO, United States. 1998.
PY:  1998
AB:  The Buck Creek Mafic-Ultramafic complex (BCUC) is a fragment of oceanic lower crust that has preserved a complex metamorphic history, due both to the varied rock types present and to contrasting rheologies. The complex covers approximately 20 sq. km and is enclosed by schists and paragneisses of the Tallulah Falls Fm. Amphibolite encloses the BC ultramafic body, dominated by dunite with lenses of variably metamorphosed troctolite. Major element compositions of BCUC rocks show a nearly continuous transition from dunite to troctolite and from troctolite to gabbro (amphibolite). Troctolite-dunite and troctolite - amphibolite are interlayered at cm to meter scales, and transitional rocks are common. Two meta-troctolite lithologies are present. A hard blue metatroctolite preserves anhydrous assemblages formed at approximately 825 degrees C and approximately 10 kbar. It is a strong unit that forms map- and outcrop-scale lenses and boudins. The hydrated meta-troctolite (edenite-margarite schist (EMS)) contains a primary assemblage of edenitic amphibole + anorthite + or - corundum + or - spinel + or - kyanite + or - zoisite with retrograde margarite. Assemblages in the EMS rocks indicate peak P-T conditions of >11 kbar and 700-850 degrees C. EMS, dunites and amphibolites on the western side of the complex, near the Chunky Gal Fault, preserve a prominent retrograde signature of approximately 525 degrees C and 4-6 kbar. Hydration appears to be tied to phases of deformation. Hydrated troctolite is most voluminous in boudin necks, the hinge regions of map-scale folds, and in shear zones, all regions where structural features may have favored local fluid infiltration. Relating structural features to anhydrous and hydrated assemblages improves constraints on the P-T history of BCUC.
AN:  1999-039588

Record 111 of 393 in GeoRef Disc 5: 1997-2001/10

TI:  Reaktsionnyye vzaimootnosheniya dolomitov s beskvartsevymi kristallicheskimi slantsami na Tsentral'nom Pamire
Translated Title:  Reaction interrelations of dolomites with quartzless crystalline schists in central Pamirs.
AU:  Litvinenko-A-K
SO:  Zapiski Vserossiyskogo Mineralogicheskogo Obshchestva = Proceedings of the Russian Mineralogical Society. 127; 3, Pages 65-72. 1998. 
PB:  Nauka. Saint Petersburg, Russian Federation. 1998.
PY:  1998
AB:  Metasomatites containing minerals with reaction structures were revealed within the highly metamorphized rocks of Muscoslavskaya series at the central Pamirs. While their study the reaction rims were observed between scapolite and rutile, kyanite, biotite, garnet, as well as between corundum and kyanite. Sphene, anorthite (itself or with corundum), high ferruginous biotite, magnesian garnet were formed as products of these reactions. Data obtained confirm an existence of the second cycle of metamorphism, which was supposed previously by investigators of the region.
AN:  1999-053953

Record 112 of 393 in GeoRef Disc 5: 1997-2001/10

TI:  Models of corundum origin from alkali basaltic terrains; a reappraisal.
AU:  Sutherland-F-Lin; Hoskin-Paul-W-O; Fanning-C-Mark; Coenraads-Robert-R
SO:  Contributions to Mineralogy and Petrology. 133; 4, Pages 356-372. 1998. 
FTXT:  SwetsNet (European Mirror) http://www.swetsnet.nl/link/access_db?issn=00107999&vol=00133&iss=00004&page=356 SwetsNet (US Mirror) http://www.swetsnet.com/link/access_db?issn=00107999&vol=00133&iss=00004&page=356 EBSCO Online http://www.ebsco.com/online/direct.asp?ArticleID=EFTRFP24D5CMRCYC3792 Springer-Verlag LINK (European Mirror) http://link.springer.de/cgi/linkref?issn=0010-7999&year=1998&volume=133&page=356 Springer-Verlag LINK (US Mirror) http://link.springer-ny.com/cgi/linkref?issn=0010-7999&year=1998&volume=133&page=356 Springer Search http://link.springer.de/search.htm /cgi/linkref?issn=0010-7999&year=1998&volume=133&page=356 InformationQuest http://www.eiq.com/usr_login.html?sici=0010-7999%28000000%29133%3A4%3C356%3AX%3E2.0.CO%3B2-X
PB:  Springer International. Heidelberg-New York, International. 1998.
PY:  1998
AN:  1999-055335

Record 113 of 393 in GeoRef Disc 5: 1997-2001/10

TI:  Textural and chemical relations among spl-spr-grt-opx, Salt Hill emery mine, Cortlandt Complex, N.Y.
AU:  Johnson-A-M; Tracy-R-J
BK:  In: AGU 1998 spring meeting.
BA:  Anonymous
SO:  Eos, Transactions, American Geophysical Union. 79; 17, Suppl., Pages 360. 1998. 
PB:  American Geophysical Union. Washington, DC, United States. 1998.
PY:  1998
AN:  1999-056239

Record 114 of 393 in GeoRef Disc 5: 1997-2001/10

TI:  Petrochemistry and origin of Archean granitic rocks of Hyderabad City.
AU:  Gnaneshwar-P; Sitaramayya-S
SO:  Indian Journal of Geology. 70; 3, Pages 249-264. 1998. 
PB:  Geological Mining & Metallurgical Society of India. Calcutta, India. 1998.
PY:  1998
AB:  Based on field relations and detailed observations near contacts of rock types, it is inferred that pyroxene granites in and around Hyderabad city are the oldest rock types of this area, followed by porphyritic grey granites, white alaskites and pink alaskites. Hybridization between white alaskites and pyroxene granites resulted in the formation of green biotite granites. Metasomatism of grey porphyritic granites by pink alaskites resulted in the formation of pink porphyritic granites. The chemical composition of six rock types of the present study indicate that each lithounit is remarkably uniform in composition and show calc-alkaline trend. These rock types range in composition from diopside (pyroxene granites, green biotite granites and porphyrites) to corundum normative (white alaskites and pink alaskites). The absence of peraluminous minerals, normative diopside, A/CNK ratio, and Rb-Ba-Sr variation in these rocks suggests their I-type nature. The whole rock chemistry and magmatic evolution trends suggest that these rocks are evolved from the same source by partial melting of older crustal rocks. The discontinuities in near-linear chemical correlations and Y-SiO (sub 2) variation indicate that there is a significant time gap between the pyroxene granite and other rock types.
AN:  1999-066176

Record 115 of 393 in GeoRef Disc 5: 1997-2001/10

TI:  Geochemistry and petrogenesis of Lower Paleozoic meta-granites of Lahaul-Spiti region, Himachal Pradesh, India.
AU:  Islam-R; Gururajan-N-S
SO:  Geochemical Journal. 31; 1, Pages 1-16. 1997. 
PB:  Geochemical Society of Japan. Nagoya, Japan. 1997.
PY:  1997
AB:  In the Lahaul-Spiti region of Himachal Pradesh two meta-granite bodies (Jispa granite and Ratilaman granite) emplaced in the low grade Haimanta Formation which is tectonically overlying the Central Crystallines. Field, petrographical and geochemical features of these meta-granites are compared with the orthogneisses of the Central Crystallines. Geochemical signatures of these meta-granites and orthogneisses suggest that they are products of peraluminous melt generated by partial melting of older crustal rock, with high A/CNK values and higher normative corundum. Decrease in Fe (sub 2) O (sub 3) , MgO, CaO, TiO (sub 2) , Sr and Zr and enhancement in K (sub 2) O, SiO (sub 2) and Rb as well as Rb/Sr ratios from melanocratic (margin) to leucocratic (core) portion of these bodies indicate that they are consistent with fractional crystallization processes. Decrease of total REE, moderate LREE/HREE ratios and more pronounced negative Eu anomalies are also in accord with fractional crystallization. The heat source for these lower Paleozoic granite magmas may be due to the lithospheric extension which resulted in mantle melting beneath the crust which led to anomalous heat flow, and triggered crustal melting. Felsic magmas thus produced have intruded into shallow crustal levels.
AN:  1997-051409

Record 116 of 393 in GeoRef Disc 5: 1997-2001/10

TI:  Near-end-member magnesiochloritoid in prograde-zoned pyrope, Dora-Maira Massif, Western Alps.
AU:  Simon-Gilla; Chopin-Christian; Schenk-Volker
BK:  In: High pressure metamorphism in nature and experiment.
BA:  Schreyer-W (editor); Stoeckhert-B (editor)
SO:  Lithos. 41; 1-3, Pages 37-57. 1997. 
FTXT:  ScienceDirect (tm) http://www.sciencedirect.com/science?_ob=GatewayURL&_origin=SilverLinker&_urlversion=4&_method=citationSearch&_volkey=0024%2d4937%2341%2337&_version=1&md5=509c6d7107dadfab2cfd117d2726ddaf
PB:  Elsevier. Amsterdam, International. 1997.
PY:  1997
AB:  In the ultrahigh-pressure metamorphic terrane of the Dora-Maira massif, western Alps, magnesiochloritoid (up to 97 mol% end-member) occurs along with ellenbergerite, talc, chlorite or kyanite as prograde inclusions in a few pyrope megablasts. Whereas most pyrope megablasts in this terrane are relatively homogeneous (Prp90-Prp98), the magnesiochloritoid-bearing megablasts commonly preserve a clear prograde Fe-Mg zonation pattern (from Prp70 to Prp98). The nearly homogeneous chloritoid inclusions also record this zonation pattern, their X (sub Mg) increasing from 0.70 to 0.96 from garnet core to garnet rim. These zonations are shown to be prograde and to record increasing P and T conditions up to about 700 degrees C, 30 kbar. The occurrence of magnesiochloritoid in some garnets simply reflects either a slightly more Fe-rich system (general case), or a more Al-rich and originally corundum-bearing system (one unzoned near-end-member pyrope megablast). Fe-Mg partitioning between chloritoid and zoned host-garnet changes from normal to reverse (i.e., X (sub Mg) (super Cld) <X (sub Mg) (super Grt) ) from core to rim, or from rim to core in other megablasts of yet similar composition. In case of reverse partitioning, a diffusion zone of a few tens of mu m wide exists in garnet around the inclusions, toward which X (sub Mg) (super Grt) decreases and reaches a normal partitioning value at the contact. These features are interpreted in terms of disequilibrium and tentatively ascribed to slow diffusion in chloritoid with respect to garnet growth rate, or to two competing garnet-forming reactions, with the metastable one, which produces a more Mg-rich garnet, being kinetically favoured. The prograde inclusions of magnesiostaurolite show a consistent Fe-Mg reversal with garnet, i.e. X (sub Mg) (super St) <X (sub Mg) (super Grt) , which is interpreted as an equilibrium feature at high pressure (and high X (sub Mg) ). Magnesiochloritoid locally breaks down into symplectites of chlorite and an extremely low-Si magnesiostaurolite (down to 7.0 Si per formula unit), which is probably metastable with respect to magnesiostaurolite+corundum.
AN:  1998-001617

Record 117 of 393 in GeoRef Disc 5: 1997-2001/10

TI:  Afyon metasedimanter grubu'nda felsik metavolkanitierin petrograf k ve jeokimyasal ozellikleri
Translated Title:  Petrographical and geochemical properties of felsic metavolcanites in the Afyon metasedimentary group.
AU:  Tolluoglu-A-Umit; Sumer-Engin-O
SO:  Yerbilimleri. 19; Pages 57-70. 1997. 
PB:  Hacettepe University, Institute of Earth Sciences. Ankara, Turkey. 1997.
PY:  1997
AB:  Afyon metamorphites are dominantly composed of sedimentary lithologies which are subdivided into two groups as Lower and Upper Metamorphites. They are unconformably overlain by the Anatolian Carbonate Platform of Middle/Upper Devonian to Upper Permian age. The Lower Metamorphite includes Doganlar schist, Cakmak quartzite and Sandikli porphyroid (felsic metavolcanites). On the other hand, the Upper Metamorphite is made of Deliktas metaconglomerate, Ballica phyllite and Iscehisar marble. The felsic metavolcanites in the Afyon Metamorphites include two rock types. According to their mineralogical-petrographical properties meta-tuffs and meta-rhyolites can be identified. The felsic metavolcanites are located in Alaca hill and Bozcal village at the southwest of Afyon. They exhibit similar metamorphism, mineralogical-petrographical and geochemical features with the Sandikli porphyroid in the west part of Sandikli area. It is accepted that the Sandikli porphyroid and felsic metavolcanites in the Afyon Metamorphites are derived from anatexitic material which affected the Lower metamorphite. They were later regionally folded as a result of a second metamorphism which affected the Upper Metamorphite. Cataclastic deformations that occurred during the latest stages of regional foliation transformed the felsic metamorphites into mylonite, protomylonite and blastomylonite. Geochemical results indicate that the felsic metavolcanites have high SiO (sub 2) content (%73-79), normative corundum (c), A/CNK >1.1 value, peraluminous character and leucocratic aspect S-type granitoid and within-plate magmatism (WPG) origin.
AN:  1998-020678

Record 118 of 393 in GeoRef Disc 5: 1997-2001/10

BK:  Geology of the Red Dwarf corundum (ruby-sapphire) deposit, Graham Ranch, western Granite Mountains, central Wyoming.
BA:  Hausel-W-Dan
SO:  Mineral Report - Geological Survey of Wyoming. 1997. 
PB:  Geological Survey of Wyoming. Laramie, WY, United States. Pages: 6. 1997.
PY:  1997
AB:  The Red Dwarf corundum deposit was investigated by the author in 1995, as part of a regional study of the geology and mineral resources of the Tin Cup district in the Granite Mountains of central Wyoming. The deposit was apparently discovered by William Marion and Lloyd Curtis while prospecting for jade in the 1930s. Branham reported that several star rubies were found by the discoverers including a few, unflawed rubies. The ruby deposit was more recently described briefly by Osterwald and others, Love, and Sutherland. During field investigations of the area, a sapphire deposit was discovered to the west of the Red Dwarf by Robert D. Odell in 1996.
RN:  MR97-1
AN:  1998-033027

Record 119 of 393 in GeoRef Disc 5: 1997-2001/10

TI:  Detailed petrology and geochemistry of a rare corundum eclogite xenolith from Obnazhennaya, Yakutia.
AU:  Qi-Qu; Taylor-L-A; Snyder-G-A; Clayton-R-N; Mayeda-T-K; Sobolev-N-V
BK:  In: Proceedings of the Sixth international kimberlite conference; Volume 1, Kimberlites, related rocks and mantle xenoliths.
BA:  Mitchell-R-H (editor); Sobolev-R-H (editor)
SO:  Russian Geology and Geophysics. 38; 1, Pages 247-260. 1997. 
PB:  Allerton Press. New York, NY, United States. 1997.
PY:  1997
AN:  1998-036033

Record 120 of 393 in GeoRef Disc 5: 1997-2001/10

TI:  Origin mechanism of hercynite-kamacite objects; evidence for liquid immiscibility phenomena in the Yamato-82133 ordinary chondrite (H3).
AU:  Zinovieva-Nina-G; Mitreikina-Olga-B; Granovsky-Lev-B
BK:  In: Papers presented at the Twenty-first symposium on Antarctic meteorites.
BA:  Anonymous
SO:  Antarctic Meteorite Research. 10; Pages 299-311. 1997. 
PB:  National Institute of Polar Research. Tokyo, Japan. 1997.
PY:  1997
AB:  Peculiar mineral aggregates detected in the nonequilibrated Yamato-82133 ordinary chondrite (H3) include regular intergrowths of hercynite and kamacite, sometimes with corundum. In addition to hercynite, kamacite, and corundum, the typical minerals of the hercynite-kamacite objects (HKO) are chrome spinels and phosphates (apatite, whitlockite, and a Ca-free Na-K analog of fillowite). HKO are most widespread in the chondrite matrix but also occur in the porphyritic pyroxene-olivine and olivine chondrules, in which HKO were detected in form of droplets. The latter stick together to produce dumbbell-shaped aggregates. Intrachondrule HKO are zoned and have magmatic textures. Their textural relationships and specific mineralogical features are indicative of the magmatic genesis of intrachondrule HKO and provide information on the composition of the parental melt. The textural identity between intrachondrule and matrix HKO and similarities in their mineral assemblages and mineral chemistries suggest their similar genesis.
AN:  1998-041112

Record 121 of 393 in GeoRef Disc 5: 1997-2001/10

TI:  High-pressure metamorphism in kyanite-bearing schists from the original Jingangku Formation of the Wutaishan.
AU:  Wang-Kaiyi; Hao-Jie; Cawood-Peter-A; Wilde-Simon-A
BK:  In: Precambrian geology and metamorphic petrology.
BA:  Qian-Xianglin (editor); You-Zhengdong (editor); Halls-H-C (editor)
SO:  Proceedings of the ... International Geological Congress. 30, Vol. 17; Pages 233-240. 1997. 
PB:  International Geological Congress. [location varies], International. 1997.
PY:  1997
AN:  1998-045761

Record 122 of 393 in GeoRef Disc 5: 1997-2001/10

TI:  The solubility of albite-paragonite-quartz at 5 kbar, 350C.
AU:  Lin-Heather; Manning-C-E
BK:  In: Geological Society of America, 1997 annual meeting.
BA:  Anonymous
SO:  Abstracts with Programs - Geological Society of America. 29; 6, Pages 400. 1997. 
PB:  Geological Society of America (GSA). Boulder, CO, United States. 1997.
PY:  1997
AB:  The solubility of Albite-Paragonite-Quartz has been measured in a pH-buffered sulfur-bearing aqueous solution at 350C, 5 kbar. There have been no other pH buffered solubility experiments in this system at these high pressure conditions. The models that allow calculation of the properties of aqueous species using the HKF equation of state are limited to (super *) 5 kbar and (super *) 1000C by the availability of experimental data on the properties of water. Therefore these experiments allow testing of such predictive models at their pressure limit. The pH of the solutions is buffered using a modification of a technique developed by Frantz and Eugster (1973) whereby gas buffers are used in concert with H (sub 2) O to fix hydronium ion concentration. A NNO oxygen buffer and a Ag-Ag2S sulfur buffer were used in these experiments. Calculated equilibrium constants and measured S concentrations then permit determination of pH. The buffer materials were placed in a 5 mm. O. D. Pt capsule with Amelia albite fragments ( approximately 1X1X2 mm), quartz cores ( approximately 2 mm dia, 1.5 mm long), fine-grained paragonite (in a separate, crimped 2 mm. capsule), and distilled, deionized H (sub 2) O. The paragonite was synthesized by taking an albite -- corundum mixture to 5 kbar and 400C for 140 hours in the presence of water. The experiments were brought stepwise to pressure and temperature in a 1" piston cylinder apparatus and allowed to equilibrate for 90+ hours. Solutions were extracted in 5% HNO3 and analyzed by ICP spectroscopy. At 5 kbar, 350C, pH was 6.97. Si had the highest solubility followed by Na and Al. (log m Si = -1.351, log m Na = -1.759, log m Al = -2.088) as in prior solubility experiments in the Na-Al-Si-O-H system (Davis, 1972; Woodland and Walther, 1986). Calculations suggest that the dominant Al complex is AlO2-. These experiments permit characterization of the mobility of Na, Al, and Si in high pressure environments, such as subduction zones and Barrovian metamorphic belts.
AN:  1998-057180

Record 123 of 393 in GeoRef Disc 5: 1997-2001/10

TI:  Cambrian granulite to upper amphibolite facies metamorphism of post-797 Ma sediments in Madagascar.
AU:  Ito-Masahiro; Suzuki-Kazuhiro; Yogo-Setsuo
SO:  The Journal of Earth and Planetary Sciences, Nagoya University. 44; Pages 89-102. 1997. 
PB:  Nagoya Daigaku Rigakubu Chikyukagaku Kyoshitsu. Nagoya, Japan. 1997.
PY:  1997
AB:  The CHIME monazite and xenotime ages were determined for two paragneisses from Madagascar. The biotite - sillimanite - cordierite - quartz - microcline - plagioclase schist at Ihosy in southern Madagascar contains core-mantle monazite grains as well as chronologically unzoned ones. The unzoned monazite grains (8 of 11 analyzed grains) give a CHIME age of 527+ or -15 Ma. Two zoned grains show core ages of 1640+ or -180 and 797+ or -75 Ma with mantles of 550+ or -50 and 535+ or -10 Ma, respectively. The kyanite- and corundum-bearing cordierite - sillimanite - muscovite - biotite - plagioclase - quartz gneiss at Maevatanana in northwestern Madagascar contains both monazite and xenotime. Monazite and xenotime grains are chronologically uniform, and give CHIME ages of 534+ or -10 and 530+ or -32 Ma, respectively. These chronological data suggest that the high-grade paragneisses in Madagascar, if not all, formed through a single thermal event at ca. 530 Ma from post-797 Ma sediments. This metamorphism can be linked to the continental collision that resulted in Gondwana supercontinent.
AN:  1998-063878

Record 124 of 393 in GeoRef Disc 5: 1997-2001/10

TI:  O geologicheskom stroyenii i k mineragenii lamprofirovykh diatrem vedinskoy ofiolitovoy zony
Translated Title:  Geological structure and minerogeny of lamprophyric diatremes of Vedinskaya ophiolite zone.
AU:  Satian-M-A; Vardanyan-A-V; Stepanyan-Zh-O; Tayan-R-N; Mnatsakanyan-A-Kh; Arutyunyan-M-A; Nisanyan-G-B
SO:  Izvestiya Natsional'noy Akademii Nauk Respubliki Armenii; Nauki o Zemle. 50; 1-2, Pages 14-24. 1997. 
PB:  Gitutyun. Yerevan, Armenia. 1997.
PY:  1997
AB:  The paper deals with the geological structure and composition of lamprophyric diatremes of the Vedy ophiolite zone. It is found out that the diatreme tuffs belong to holohyaline differences of alkaline lamprophyres, the tuffs are of the Early Cretaceous and the diatreme dykes are of the Late Cretaceous, the structural control with faults and folding relate to the Post Valanginian-Pre-Late Albian stage in the ophiolites. A potential perspectivity with respect to precious minerals of the corundum group and a possibility to use tuffs for production of glassy ceramics and coloured glass are found out as well.
AN:  1998-069645

Record 125 of 393 in GeoRef Disc 5: 1997-2001/10

TI:  Provenance studies in the Yerrida Basin; initial report.
AU:  Adamides-Nicos-G
BK:  In: Geological Survey of Western Australia; annual review 1996-97.
BA:  Johnston-J-F (editor); Nowak-I-R (editor)
SO:  Geological Survey of Western Australia, Annual Review. 1996-97; Pages 104-109. 1997. 
PB:  Western Australia Geological Survey. Perth, West. Aust., Australia. 1997.
PY:  1997
AB:  The Yerrida Basin is one of several Palaeoproterozoic ensialic sedimentary basins that resulted from the collision of the Yilgarn and Pilbara Cratons around 2.0-1.8 Ga. Within this basin, the Doolgunna and Thaduna Formations represent turbidite facies that are probably temporally and stratigraphically related. The Doolgunna Formation is a kaolinitic wacke of granitic derivation. It is characterized by a clastic assemblage of quartz and feldspar and a heavy-mineral suite of zircon, schorlite, corundum, apatite, topaz, cassiterite, and fluorite. On the QFL diagram, samples from this unit occupy the field of continental block provenance. The Thaduna Formation is characterized by a varied assemblage of clasts and minerals of mafic igneous derivation, intermixed with sedimentary components. The heavy-mineral fraction is dominated by epidote, subordinate clinopyroxene, and detrital opaque minerals of the titanomagnetite group. These show a variety of textures (sandwich-type, trellis) suggesting similarly varied source rocks. Samples from this formation occupy the field of magmatic are provenance. Interaction between the sedimentary environments of the Doolgunna and Thaduna Formations is inferred from field relationships as well as from mixed heavy-mineral assemblages.
AN:  1998-070063

Record 126 of 393 in GeoRef Disc 5: 1997-2001/10

TI:  Laprofirovyye diatremy Vedinskoy ofiolitovoy zony (Armeniya)
Translated Title:  Lamprophyre diatremes of the Vedinskaya ophiolite zone; Armenia.
AU:  Satian-M-A; Vardanyan-A-V; Stepanyan-Zh-O; Tayan-R-N; Mnatsakanyan-A-Kh; Atutunyan-M-A
SO:  Izvestiya Vysshikh Uchebnykh Zavedeniy. Geologiya i Razvedka. 1997; 3, Pages 63-73. 1997. 
PB:  Ministerstvo Obshchego i Professional'nogo Obrazovaniya Rossiyskoy Federatsii. Moscow, Russian Federation. 1997.
PY:  1997
AB:  The geological structure and rock composition of lamprophyric diatremes newly found in the Vedinskaya ophiolite zone were studied. It was established that filling tuffs represent holohyaline varieties of alkaline lamprophyres. The diatremes are dated at Cretaceous, they are structurally controlled by post-Valanginian-pre-Late Albian faults within the ophiolite zones. Telescoped development of the diatremes and their potential prospectivity for gem minerals of corundum group were established.
AN:  1999-007976

Record 127 of 393 in GeoRef Disc 5: 1997-2001/10

TI:  Asociace mineralu vyznamnejsich pegmatitovych zil v hatich u dolnich boru na zapadni Morave
Translated Title:  Mineral assemblages of significant pegmatite dikes from the Hate area near Dolni Bory, western Moravia.
AU:  Stanek-Josef
SO:  Acta Musei Moraviae. Scientiae Geologicae. Casopis Moravskeho Muzea. 82; Pages 3-19. 1997. 
PB:  Moravske Zemske Muzeum. Brno, Czech Republic. 1997.
PY:  1997
AB:  Significant pegmatite dikes from Dolni Bory Dikes No. 1, 3, 4, 5, 6, 7, 8 and Oldrich were selected and localized within the Hate area. Their mineral assemblages were specified in detail with respect to minor and accessory minerals and the minerals typical for the individual dikes. The pegmatite from the Hate area near Dolni Bory are typical Al-rich with volumentarically abundant andalusite, schorl, sekaninaite muscovite and several accessory minerals such as corundum, diaspore, pyrophyllite, dumortierite, chloritoid and augelite. Iron is also a typical element in the studied pegmatites, it is dominant in almost all Fe. Mg. Mn minerals: sekaninaite, schorl, almandine, zwieselite, triphylite, ilmenite, wolframite.
AN:  1999-024248

Record 128 of 393 in GeoRef Disc 5: 1997-2001/10

TI:  Metamorphism of Al-rich gneisses in Taihang Mountain Archean metamorphic complex.
AU:  Liu-Shuwen; Liang-Haihua
SO:  Yanshi Xuebao = Acta Petrologica Sinica. 13; 3, Pages 303-312. 1997. 
PB:  Science Press. Beijing, China. 1997.
PY:  1997
AB:  Al-rich gneisses in the Taihang Mountain Archean metamorphic complex are mainly distributed in the lower part of the Wanzi stratified rock series and the gneisses are usually associated with various marbles or occur as stratified bodies in granitic gneisses. The evolution of their metamorphism involves three stages. Through garnet-biotite thermometry and internally consistent thermodynamic calculation, we found garnet, staurolite and rutile assemblage was formed at 680 degrees C and 0.8 GPa, corundum- and gedrite-present mineral assemblage at 730-750 degrees C and about 0.7 GPa. The temperature of sillimanite- and hercynite-present mineral assemblage is a little higher than that of second association, yet pressure is less than that of the second assemblage.
AN:  1999-032486

Record 129 of 393 in GeoRef Disc 5: 1997-2001/10

TI:  Spinel-corundum-alkali feldspar in Jinling Complex, Shandong; the discovery of a very rare Al-rich metasomatite.
AU:  Li-Daxin; Zhao-Yiming
SO:  Yanshi Kuangwuxue Zazhi = Acta Petrologica et Mineralogica. 16; 1, Pages 44-49. 1997. 
PB:  Dizhi Chubanshe. Beijing, China. 1997.
PY:  1997
AN:  1999-033099

Record 130 of 393 in GeoRef Disc 4: 1993-1996

TI:  Corundum, rutile, periclase, and CaO in Ca,Al-rich inclusions from carbonaceous chondrites.
AU:  Greshake-A; Bischoff-A; Putnis-A; Palme-H
SO:  Science. 272; 5266, Pages 1316-1318. 1996. 
FTXT:  Journals@OVID http://gateway.ovid.com/ovidweb.cgi?T=JS&PAGE=fulltext&D=ovft&NEWS=n&DBC=n&AN=00007529-199605310-00014 HighWire http://www.sciencemag.org/cgi/content/full/272/5266/1316
PB:  American Association for the Advancement of Science. Washington, DC, United States. 1996.
PY:  1996
AN:  1996-042638

Record 131 of 393 in GeoRef Disc 4: 1993-1996

TI:  Pure CaO, MgO (periclase), TiO (sub 2) (rutile), and Al (sub 2) O (sub 3) (corundum) in Ca, Al-rich inclusions from carbonaceous chondrites.
AU:  Greshake-A; Bischoff-A; Putnis-A
SO:  Abstracts of Papers Submitted to the Lunar and Planetary Science Conference. 27, Part 1; Pages 463-464. 1996. 
PB:  Lunar and Planetary Science Conference. Houston, TX, United States. 1996.
PY:  1996
AN:  1996-051191

Record 132 of 393 in GeoRef Disc 4: 1993-1996

TI:  Quantitative mineralogical analysis of coals from the Callide Basin, Queensland, Australia using X-ray diffractometry and normative interpretation.
AU:  Ward-Colin-R; Taylor-John-C
SO:  International Journal of Coal Geology. 30; 3, Pages 211-229. 1996. 
FTXT:  ScienceDirect (tm) http://www.sciencedirect.com/science?_ob=GatewayURL&_origin=SilverLinker&_urlversion=4&_method=citationSearch&_volkey=0166%2d5162%2330%23211%233&_version=1&md5=78673173d75e31da6377b135d959979f
PB:  Elsevier. Amsterdam, International. 1996.
PY:  1996
AB:  Comparisons are presented between the results of quantitative X-ray diffractometry using a Rietveld-based computational method (SIROQUANT) on low-temperature ash (LTA) and normative calculation from chemical analysis of high-temperature ash for a series of coal samples from the Callide Basin of Queensland. Mineral percentages indicated by each method are also compared to the results of conventional X-ray diffractometry on low-temperature ash spiked with a known proportion of corundum, evaluated in conjunction with detailed clay mineral analysis of the <2 mu m fraction of each sample by oriented-aggregate X-ray diffraction methods. For species where direct comparison is possible, the proportions of the different minerals in the crystalline fraction indicated by SIROQUANT are similar to those indicated by normative analysis using a computational procedure referred to as SEDNORM. More conventional XRD study of spiked LTA materials, with the samples studied, seems to underestimate quartz and siderite content, and by default overestimate kaolinite. SIROQUANT, on the other hand, tends to overestimate the proportion of Ca-bearing minerals, relative to the Ca content of the high-temperature ash, processed using the SEDNORM computation. Both the SIROQUANT analysis and the normative evaluation of SEDNORM provide significantly more quantitative information on coal mineralogy than other more commonly used techniques.
AN:  1996-063688

Record 133 of 393 in GeoRef Disc 4: 1993-1996

TI:  A quartz-corundum assemblage from the western Adirondacks.
AU:  Morgia-Nicholas-D; Darling-Robert-S
BK:  In: Geological Society of America, Northeastern Section, 31st annual meeting.
BA:  Anonymous
SO:  Abstracts with Programs - Geological Society of America. 28; 3, Pages 85. 1996. 
PB:  Geological Society of America (GSA). Boulder, CO, United States. 1996.
PY:  1996
AN:  1996-065070

Record 134 of 393 in GeoRef Disc 4: 1993-1996

TI:  Sapphirine-bearing equilibria in the system MgO-Al (sub 2) O (sub 3) -SiO (sub 2) .
AU:  Podlesskii-K-K-(Podlesskiy-K-K)
BK:  In: Sixth international symposium on Experimental mineralogy, petrology and geochemistry.
BA:  Anonymous
SO:  Terra Abstracts. 8, Suppl. 1; Pages 51. 1996. 
PB:  Blackwell Scientific Publications. Oxford, International. 1996.
PY:  1996
AN:  1996-065407

Record 135 of 393 in GeoRef Disc 4: 1993-1996

TI:  Reaction textures in contact-metamorphosed xenoliths; implications for the tectonothermal evolution of the Seiland igneous province, Norwegian Caledonides.
AU:  Elvevold-Synnove; Reginiussen-Helge
SO:  European Journal of Mineralogy. 8; 4, Pages 777-789. 1996. 
PB:  Schweizerbart'sche Verlagsbuchhandlung (Naegele u. Obermiller). Stuttgart, Federal Republic of Germany. 1996.
PY:  1996
AN:  1996-066133

Record 136 of 393 in GeoRef Disc 4: 1993-1996

TI:  Corundum from basaltic terrains; a mineral inclusion approach to the enigma.
AU:  Guo-J; O-Reilly-S-Y; Griffin-W-L
SO:  Contributions to Mineralogy and Petrology. 122; 4, Pages 368-386. 1996. 
PB:  Springer International. Heidelberg-New York, International. 1996.
PY:  1996
AN:  1996-066688

Record 137 of 393 in GeoRef Disc 4: 1993-1996

TI:  Zircon inclusions in corundum megacrysts; I, Trace element geochemistry and clues to the origin of corundum megacrysts in alkali basalts.
AU:  Guo-Jingfeng; O-Reilly-S-Y; Griffin-W-l
SO:  Geochimica et Cosmochimica Acta. 60; 13, Pages 2347-2363. 1996. 
FTXT:  ScienceDirect (tm) http://www.sciencedirect.com/science?_ob=GatewayURL&_origin=SilverLinker&_urlversion=4&_method=citationSearch&_volkey=0016%2d7037%2360%232347%2313&_version=1&md5=b9b9f95740b95b43fc4a64654d30c942
PB:  Pergamon. Oxford, International. 1996.
PY:  1996
AN:  1996-071170

Record 138 of 393 in GeoRef Disc 4: 1993-1996

TI:  An unusual ruby-sapphire-sapphirine-spinel assemblage from the Tertiary Barrington volcanic province, New South Wales, Australia.
AU:  Sutherland-F-Lin; Coenraads-Robert-R
SO:  Mineralogical Magazine. 60; 4, Pages 623-638. 1996. 
PB:  Mineralogical Society. London, United Kingdom. 1996.
PY:  1996
AN:  1996-073284

Record 139 of 393 in GeoRef Disc 4: 1993-1996

TI:  Corundum-quartz-bearing assemblage in the Ihouhaouene area (In Ouzzal, Algeria).
AU:  Guiraud-M; Kienast-J-R; Ouzegane-K
BK:  In: Special issue on the In Ouzzal granulite unit, Hoggar, Algeria.
BA:  Kienast-J-R (editor); Fourcade-S (editor); Guiraud-M (editor); Hensen-B-J (editor); Ouzegane-K (editor)
SO:  Journal of Metamorphic Geology. 14; 6, Pages 755-761. 1996. 
PB:  Blackwell. Oxford, United Kingdom. 1996.
PY:  1996
AN:  1997-005098

Record 140 of 393 in GeoRef Disc 4: 1993-1996

TI:  Occurrence of oxides in minerals of Ca, Al-rich inclusions from carbonaceous chondrites; Al (sub 2) O (sub 3) (corundum), TiO (sub 2) (rutile), MgO (periclase), and CaO.
AU:  Greshake-A; Bischoff-A; Putnis-A; Palme-H
BK:  In: 59th annual Meteoritical Society meeting; abstracts.
BA:  Sears-Derek-W-G (editor)
SO:  Meteoritics and Planetary Science. 31, Suppl.; Pages 54. 1996. 
PB:  Meteoritical Society. Fayetteville, AR, United States. 1996.
PY:  1996
AN:  1997-010482

Record 141 of 393 in GeoRef Disc 4: 1993-1996

TI:  Timing of emplacement of the sapphire-bearing Yogo Dike, Little Belt Mountains, Montana.
AU:  Harlan-Stephen-S
SO:  Economic Geology and the Bulletin of the Society of Economic Geologists. 91; 6, Pages 1159-1162. 1996. 
PB:  Economic Geology Publishing Company. Lancaster, PA, United States. 1996.
PY:  1996
AN:  1997-026472

Record 142 of 393 in GeoRef Disc 4: 1993-1996

TI:  Iridium metal, calcium-aluminum-rich inclusions in Chicxulub impact melt; relicts of a carbonaceous chondrite K-T boundary impactor.
AU:  Schuraytz-Benjamin-C; Lindstrom-David-J; Morrison-Donald-A; Sharpton-Virgil-L
BK:  In: Geological Society of America, 28th annual meeting.
BA:  Anonymous
SO:  Abstracts with Programs - Geological Society of America. 28; 7, Pages 108. 1996. 
PB:  Geological Society of America (GSA). Boulder, CO, United States. 1996.
PY:  1996
AN:  1997-075507

Record 143 of 393 in GeoRef Disc 4: 1993-1996

TI:  Size effect of aluminum ultrafine particles on formation of alumina phase.
AU:  Kimura-Seiji; Tamura-Nobuyasu; Tsuda-Noritoshi; Saito-Yashio; Koike-Chiyoe; Kaito-Chihiro
BK:  In: Antarctic meteorites XXI; papers presented to the Twenty-first symposium on Antarctic meteorites.
SO:  Papers Presented to the ... Symposium on Antarctic Meteorites. 21; Pages 70-72. 1996. 
PB:  National Institute of Polar Research. Tokyo, Japan. 1996.
PY:  1996
AN:  1998-057932

Record 144 of 393 in GeoRef Disc 4: 1993-1996

TI:  Sapphirine+spinel+corundum+quartz association from granulite of Paderu, Vishakapatnam District, A.P.
AU:  Singh-S-P
SO:  Indian Mineralogist. 30; Pages 20-30. 1996. 
PB:  Mineralogical Society of India. Mysore, India. 1996.
PY:  1996
AB:  Corundum + quartz and corundum + sillimanite + quartz, along with hemoilmenite + (Magnetite-hercynite) as + sapphirine+ spinel association has been noticed from the sapphirine-spinel-bearing granulites of Paderu. The corundum related reaction textures are mainly associated with various corona textures of other refractory phases viz, spinel, sapphirine, sillimanite in the matrix of quartz. The mineral chemistry of corundum and associated mineral paragenesis show high content of Fe (sub 2) O (sub 3) . It is suggested here that unusual coexistence of corundum + quartz and sapphirine + spinel + corundum + quartz are possibly due to oxidation of FeO rich spinel and sapphirine phases in the matrix of quartz within the stability field of spinel + sapphirine + quartz during the early stage of retrograde metamorphism of granulite of Paderu.
AN:  1999-069589

Record 145 of 393 in GeoRef Disc 4: 1993-1996

TI:  Comment on "Measurement of the PVT properties of water to 25 kbars and 1600 degrees C from synthentic fluid inclusions in corundum" by J. P. Brodholt and B. J. Wood; reply.
AU:  Duan-Zhenhao; Moller-Nancy; Weare-John-H
SO:  Geochimica et Cosmochimica Acta. 59; 12, Pages 2639-2641. 1995. 
PB:  Pergamon. Oxford, International. 1995.
PY:  1995
AN:  1995-051842

Record 146 of 393 in GeoRef Disc 4: 1993-1996

TI:  High-grade metamorphism and retrogression of Moldanubian granulites, Austria.
AU:  Petrakakis-Konstantin; Jawecki-Christine
SO:  European Journal of Mineralogy. 7; 5, Pages 1183-1203. 1995. 
PB:  Schweizerbart'sche Verlagsbuchhandlung (Naegele u. Obermiller). Stuttgart, Federal Republic of Germany. 1995.
PY:  1995
AN:  1996-001707

Record 147 of 393 in GeoRef Disc 4: 1993-1996

TI:  Des xenolites a corindon dans une vaugnerite de l'Ardeche (Massif Central francais); implications pour le metamorphisme ardechois
Translated Title:  Corundum-bearing xenoliths in Ardeche vaugnerite, French Central Massif; implications for Ardeche metamorphism.
AU:  Ait-Malek-Halima; Gasquet-D; Marignac-C; Bertrand-J-M
SO:  Comptes Rendus de l'Academie des Sciences, Serie II. Sciences de la Terre et des Planetes. 321; 11, Pages 959-966. 1995. 
PB:  Gauthier-Villars. Montrouge, France. 1995.
PY:  1995
AB:  Xenoliths from the Loubaresse (Ardeche) vaugneritic sill are slivers of the metapelitic country rocks. Some of them are partially melted and experienced desilicification. Corundum that appears in the xenoliths is due to early emplacement of the mafic magma, before the LP-HT M3 metamorphic climax.
AN:  1996-071084

Record 148 of 393 in GeoRef Disc 4: 1993-1996

TI:  Dokazatel'stva lokal'nogo anateksisa v vysokotemperaturnom kontaktovom oreole dioritov intruzivnogo kompleksa Glen Lednok, Komri, Shotlandiya
Translated Title:  Evidence for local anatexis at high-temperature diorite contacts of the Glen Lednock plutonic complex, Comrie, Scotland.
AU:  Uayld-S-A-(Wilde-S-A)
SO:  Petrologiya. 3; 3, Pages 228-247. 1995. 
PB:  MAIK "Nauka". Moscow, Russian Federation. 1995.
PY:  1995
AB:  The Glen Lednock plutonic complex (Komrie Mountain, Scotland) includes eighteen individual intrusion phases and occurs near the Highland Boundary Fault in turbidites of the Dalradian Supergroup, metamorphized in the conditions of greenschist facies. High-temperature contact aureol is developed here, and internal zone of pyroxene hornfels facies is characterized by intense manifestation of cordierite hornfels, high in iron and magnesium, in association with metapelites, poor in silica (enriched with cordierite, spinel, and corundum), and metapsammites. Melts formed in two different regions are noticeably differed. In the Lednok River region (to south-west from Belmuick) they close to the triple minimum in Qtz-Ab-Or system at pressure about 0.5 kbar. At the time, granite melts of Creppich-Hill are considerably enriched with albite approaching in composition to trondhjemites. But these melts are similar in composition to restites associated with them and rich in cordierite. This fact suggests the equilibrium during melting. For the formation of anatectic melts in Comrie diorite contacts, the temperature higher than 750 C is necessary. Such proposal may be considered as a competent one considering intense adsorption by melt of refractory xenolite hornfels and the basic type of diorites justifying that magmatic temperatures could be close to the temperatures of basaltic magmas.
AN:  1998-047419

Record 149 of 393 in GeoRef Disc 4: 1993-1996

TI:  Study on mineralogy of hypersthene-cordierite granite suite along Darongshan-Shiwandashan zone in Guangxi, China.
AU:  Wang-Shaonian
SO:  Guangxi Dizhi = Guangxi Geology. 8; 1, Pages 1-13. 1995. 
PB:  Guangxi Bureau of Geology and Natural Resources. Nanning, China. 1995.
PY:  1995
AB:  Situated in the Hercynian-Indosinian folded zone of southeastern Guangxi, China, the hypersthene cordierite granite suite along the Darongshan-Shiwandashan rock zone abounds with cordierite, hypersthene, garnet, sillimanite, andalusite, and corundum, etc.. Its mineral association in complicated and its origin can be divided into three types: magmatic crystallization, metamorphosed residual and reaction types. According to the characteristics of minerals of various rocks, it is considered that the granitoid of the suite derived from the nonmelted residue of deep-seated melted granitic magma, partly from the nonmelted residue of xenoliths of country rocks metamorphosed first and then reformed by melted magma. The granitoid belongs to the crust-derived type granite produced from regional metamorphic rocks through different temperatures and pressures and deep-seated melting in different depths.
AN:  1999-012586

Record 150 of 393 in GeoRef Disc 4: 1993-1996

TI:  Upper-mantle system olivine-clinopyroxene-corundum coesite; melting relations, magma generation and differentiation.
AU:  Litvin-Yu-A
BK:  In: International Union of Geodesy and Geophysics; XXI general assembly; abstracts.
BA:  Anonymous
SO:  International Union of Geodesy and Geophysics, General Assembly. 21, Week A; Pages 393. 1995. 
PB:  [publisher varies]. [location varies], International. 1995.
PY:  1995
AN:  1999-028617

Record 151 of 393 in GeoRef Disc 4: 1993-1996

TI:  Evidence for prograde metamorphic evolution of Sri Lankan pelitic granulites, and implications for the development of continental crust.
AU:  Hiroi-Yoshikuni; Ogo-Yoshie; Namba-Keiko
BK:  In: Tectonic, metamorphic and isotopic evolution of deep crustal rocks, with special emphasis on Sri Lanka.
BA:  Raith-M (editor); Hoernes-S (editor)
SO:  Precambrian Research. 66; 1-4, Pages 245-263. 1994. 
PB:  Elsevier. Amsterdam, International. 1994.
PY:  1994
AB:  Petrological evidence for prograde metamorphic evolution is obtained for pelitic granulites of the newly defined Highland Complex in Sri Lanka. It includes the occurrences of relict kyanite+ or -quartz, staurolite, corundum+ or -kyanite, hercynite+kyanite and sapphirine+kyanite+ or -spinel within garnet in the sillimanite-quartz-rich rocks. Of special interest is the mineralogy of khondalites (graphitic garnet-sillimanite-K-feldspar-quartz gneisses), the matrix of which is free of hydrous minerals indicating that dehydration reactions have been completed in this kind of rocks. However, relict hydrous minerals such as Al-Ti-rich (more than 58 wt% Al (sub 2) O (sub 3) and more than 1 wt% TiO (sub 2) ) staurolite and extremely Ti-rich (up to 9.8 wt% TiO (sub 2) ) biotite occur as inclusions within garnet. The local relict mineral assemblages within garnet in khondalites indicate the following continuous staurolite-breakdown reactions which may have progressed as temperature increased and pressure decreased: staurolite+quartz=kyanite+garnet+H (sub 2) O; staurolite=corundum+kyanite+garnet+H (sub 2) O; staurolite=kyanite+hercynite+garnet+H (sub 2) O; staurolite=sillimanite+hercynite+garnet+H (sub 2) O. Some of these dehydration reactions are inferred to have also taken place in other widespread pelitic granulites of the Highland Complex. Moreover, garnet in the Highland Complex pelitic granulites occasionally preserves growth zoning, though modified slightly to extensively by post-growth volume diffusion. Based on the evidence, a clockwise prograde P-T path of evolution is inferred for meta-sedimentary granulites belonging to the Highland Complex. On the other hand, no evidence for prograde metamorphism has so far been obtained in "lower-grade" rocks of the Wanni Complex to the northwest of the Highland Complex. Such a difference between these complexes may be the first petrological feature which supports the new geotectonic division of the Sri Lankan basement rocks based virtually on the distinctly different neodymium model ages. It suggests that these two complexes were amalgamated during the very last part of prograde metamorphism of the Highland Complex rocks, that is during decompression and heating, probably by the lower crustal flow lateral flow after tectonic overthickening and delamination. The clockwise prograde P-T-t path followed by the meta-sedimentary granulites of the Highland Complex is in marked contrast with the near isobaric cooling path for meta-igneous granulites suggested by some authors. It is proposed that both types of P-T-t paths, albeit for different rock types, are possible and resulted from diverse deep crustal processes, such as underplating of continental crust by sediments and magmas at or near convergent plate boundaries.
AN:  1994-019629

Record 152 of 393 in GeoRef Disc 4: 1993-1996

TI:  Measurements of the PVT properties of water to 25 kbars and 1600 degrees C from synthetic fluid inclusions in corundum.
AU:  Brodholt-John-P; Wood-Bernard-J
SO:  Geochimica et Cosmochimica Acta. 58; 9, Pages 2143-2148. 1994. 
PB:  Pergamon. Oxford, International. 1994.
PY:  1994
AN:  1994-033053

Record 153 of 393 in GeoRef Disc 4: 1993-1996

TI:  Minerals and meteorites.
AU:  Jones-Bob
SO:  Rock and Gem. 24; 5, Pages 58-59, 82-84. 1994. 
PB:  Behn-Miller Publishers. Encino, CA, United States. 1994.
PY:  1994
AN:  1994-036952

Record 154 of 393 in GeoRef Disc 4: 1993-1996

TI:  Metamorphosed gabbros and troctolites from the Chunky Gal Mountain Complex, North Carolina; straddling the amphibolite-granulite facies transition?.
AU:  Farrier-Katherine-R; Ranson-William-A
BK:  In: Geological Society of America, Southeastern Section, 43rd annual meeting.
BA:  Anonymous
SO:  Abstracts with Programs - Geological Society of America. 26; 4, Pages 14. 1994. 
PB:  Geological Society of America (GSA). Boulder, CO, United States. 1994.
PY:  1994
AN:  1994-040080

Record 155 of 393 in GeoRef Disc 4: 1993-1996

TI:  The stability of lawsonite and zoisite at high pressures; experiments in CASH to 92 kbar and implications for the presence of hydrous phases in subducted lithosphere.
AU:  Schmidt-Max-W; Poli-Stefano
SO:  Earth and Planetary Science Letters. 124; 1-4, Pages 105-118. 1994. 
PB:  Elsevier. Amsterdam, Netherlands. 1994.
PY:  1994
AB:  The breakdown reactions of lawsonite in SiO (sub 2) +H (sub 2) O- and in Al (sub 2) O (sub 3) +H (sub 2) O-saturated synthetic CASH systems were examined between 17 and 92 kbar in both forward and reversed experiments. Lawsonite is stable to 565 degrees C at 20 kbar, 760 degrees C at 40 kbar, and 980 degrees C at 65 kbar. In this pressure range lawsonite breaks down to zoisite + kyanite + quartz/coesite + H (sub 2) O. An invariant point occurs at 1000 degrees C, 67 kbar. At higher pressures lawsonite breaks down to the assemblage grossular + kyanite + coesite +H (sub 2) O. The steep positive dP/dT slope of this higher pressure breakdown reaction becomes steeply negative when coesite transforms to stishovite. At 92 kbar, the highest pressure investigated, lawsonite is stable to 1040 degrees C. The invariant point marks also the pressure stability limit of zoisite since zoisite reacts to lawsonite + grossular + kyanite + coesite (at temperatures below 1000 degrees C), to grossular + kyanite + coesite + H (sub 2) O (1000-1040 degrees C) and to grossular + kyanite + melt + H (sub 2) O (above 1040 degrees C). These three reactions have a flat Clapeyron slope, and they locate the maximum pressure stability of zoisite between 65 and 68 kbar (between 800 and 1200 degrees C). Eutectic melting in the SiO (sub 2) + H (sub 2) O-saturated CASH system occurs for the assemblage zoisite + kyanite + coesite + H (sub 2) O at temperatures approximately 100 degrees C (at 40 kbar) to 40 degrees C (at 65 kbar) higher than the lawsonite breakdown reaction. In the Al (sub 2) O (sub 3) + H (sub 2) O-saturated system the reaction lawsonite + diaspore/corundum = zoisite + kyanite + H (sub 2) O limits the stability of lawsonite. The diaspore = corundum + H (sub 2) O equilibrium is found to be located about 50 degrees C lower than predicted by previous studies. The equilibrium boundaries of the reactions between 17 and 38 kbar from both SiO (sub 2) + H (sub 2) O- and Al (sub 2) O (sub 3) + H (sub 2) O-saturated chemical systems were used to improve the thermochemical data on lawsonite. Two sets of thermodynamic properties internally consistent with the databases of both Berman [1] and Holland and Powell [2], and also consistent with most previous experimental studies, were calculated employing the technique of linear programming (for Berman's data) and a least-squares fit procedure (for Holland and Powell's data). The unit cell volume of lawsonite was determined (674.67 + or - 0.38 Aa (super 3) ) and G (super o) (sub formation) and S (super o) (sub third law) were fitted. A revised G (super o) of -4 513 333 J.mol (super -1) and S (super o) of 217.45 J.K (super -1) .mol (super -1) , and a revised G (super o) of -4 517 466 J.mol (super -1) and S (super o) of 217.06 J.K (super -1) .mol (super -1) result, internally consistent with [1] and with [2], respectively. Because lawsonite is stable to 1040 degrees C at 92 kbar, a temperature far higher than predicted by thermal modelling of subduction zones, it is expected to be stable in metabasalts and intermediate compositions (e.g., andesites and greywackes) subducted to depths exceeding 300 km. Lawsonite contains 11 wt% water in its structure, and is thus capable of transporting water deep into the mantle. Its breakdown would contribute significantly to the fluid budget of the slab and overlying mantle wedge. The experimental data in combination with thermal modelling studies indicate that a complete dehydration of the descending oceanic crust is unlikely to occur at shallow levels.
AN:  1994-040777

Record 156 of 393 in GeoRef Disc 4: 1993-1996

TI:  Mineralogy and geochemistry of Bobov Dol coals, Bulgaria.
AU:  Vassilev-Stanislav-V; Yossifova-Mariana-G; Vassileva-Christina-G
SO:  International Journal of Coal Geology. 26; 3-4, Pages 185-214. 1994. 
PB:  Elsevier. Amsterdam, International. 1994.
PY:  1994
AB:  The mineralogy, elemental composition, and modes of occurrence of 49 elements in nine composite samples of Bobov Dol high-ash coals were studied by optical microscopy, scanning and transmission electron microscopy, X-ray diffractometry and chemical analysis. The major minerals were quartz, kaolinite, illite, plagioclase and K-feldspar and the minor minerals and phases were pyrite, marcasite, siderite, calcite, dolomite, gypsum, muscovite, montmorillonite and volcanic glass. The accessory minerals include a wide variety of minerals, such as galena, pyrrhotite, magnetite, hematite, goethite, chromite, rutile, anatase, corundum, gibbsite, biotite, chlorite, zircon, enstatite, garnet, jarosite, alunite, barite, polyhalite, aragonite, ankerite, witherite, apatite, halite and sylvite. The modes of occurrence and some genetic peculiarities of the above-mentioned minerals are described. Thirty-three elements occurred in concentrations higher than the respective Clarke values; especially S, Rb, Nb, Hf, Zn, Cu, Pb, Mn, Ti and U. The concentration trends and modes of occurrence of the trace elements are also discussed. In decreasing order of significance, the trace elements probably occur as element-organic compounds, as impurities in the mineral constituents, as major components in the minerals, as major and impurity components in the inorganic amorphous constituents, and in the fluid constituents. The Bobov Dol coals have undergone complex syngenetic, diagenetic and epigenetic mineralization processes associated with hydrothermal and volcanic activities. These processes were also accompanied by intensive tectonic movements and, possibly, by a later change from continental to marine sedimentation in the area after burial of the coal.
AN:  1994-056509

Record 157 of 393 in GeoRef Disc 4: 1993-1996

TI:  Tohdite (5Al (sub 2) O (sub 3) .H (sub 2) O) in bauxites from northern Australia.
AU:  Tilley-David-B; Eggleton-Richard-A
SO:  Clays and Clay Minerals. 42; 4, Pages 485-488. 1994. 
PB:  Clay Minerals Society. Clarkson, NY, United States. 1994.
PY:  1994
AN:  1995-005651

Record 158 of 393 in GeoRef Disc 4: 1993-1996

TI:  Ruby/ sapphire-Cr-silicate rocks; metasomatic products of greywacke schist and serpentinite, Southern Alps, New Zealand.
AU:  Grapes-R-H
BK:  In: International Mineralogical Association, 16th general meeting; abstracts.
BA:  Anonymous
SO:  Abstracts of the ... General Meeting of the International Mineralogical Association. 16; Pages 154. 1994. 
PB:  International Mineralogical Association. [location varies], International. 1994.
PY:  1994
AN:  1995-025705

Record 159 of 393 in GeoRef Disc 4: 1993-1996

TI:  On the phase equilibrium versus pressure periclase+corundum <--> spinel; a quantum-mechanical calculation.
AU:  Catti-M; Valerio-G; Dovesi-R; Causa-M
BK:  In: International Mineralogical Association, 16th general meeting; abstracts.
BA:  Anonymous
SO:  Abstracts of the ... General Meeting of the International Mineralogical Association. 16; Pages 66. 1994. 
PB:  International Mineralogical Association. [location varies], International. 1994.
PY:  1994
AN:  1995-026741

Record 160 of 393 in GeoRef Disc 4: 1993-1996

TI:  Ultra-high-pressure mineral assemblage of Dabie Shan metamorphic rocks, eastern China.
AU:  Xu-Shutong
BK:  In: International Mineralogical Association, 16th general meeting; abstracts.
BA:  Anonymous
SO:  Abstracts of the ... General Meeting of the International Mineralogical Association. 16; Pages 445-446. 1994. 
PB:  International Mineralogical Association. [location varies], International. 1994.
PY:  1994
AN:  1995-046881

Record 161 of 393 in GeoRef Disc 4: 1993-1996

TI:  Interstellar corundum and spinel from the Tieschitz ordinary chondrite.
AU:  Nittler-L; Alexander-C; Gao-X; Walker-R; Zinner-E
BK:  In: Twenty-fifth lunar and planetary science conference; abstracts of papers.
BA:  Anonymous
SO:  Abstracts of Papers Submitted to the Lunar and Planetary Science Conference. 25, Part 2; Pages 1005-1006. 1994. 
PB:  Lunar and Planetary Science Conference. Houston, TX, United States. 1994.
PY:  1994
AN:  1996-010980

Record 162 of 393 in GeoRef Disc 4: 1993-1996

TI:  Corundum in the Minnesota River valley peridotite.
AU:  Chan-Chien-Lu
BK:  In: AGU 1994 spring meeting.
BA:  Anonymous
SO:  Eos, Transactions, American Geophysical Union. 75; 16, Suppl., Pages 188. 1994. 
PB:  American Geophysical Union. Washington, DC, United States. 1994.
PY:  1994
AN:  1996-022341

Record 163 of 393 in GeoRef Disc 4: 1993-1996

TI:  The study on the sequence of metamorphism and deformation in metapelites from Liaohe Group in the Dashiqiao-Haicheng area, Liaoning, China.
AU:  Chen-Manyun; Huang-Zhi-an
SO:  Liaoning Dizhi = Liaoning Geology. 1994; 1-2, Pages 44-53. 1994. 
PB:  Bureau of Geology and Mineral Resources of Liaoning Province. Shenyang, China. 1994.
PY:  1994
AB:  Metapelites from Liaohe Group are one of the main types of metamorphic rock in Dashiqiao-Haicheng area, which have been undergone three phases of deformation. The foliation (S1) formed in the first phase of deformation widely distributed in the metamorphic rocks; in the second phase of deformation, crenulation cleavage (S2) mainly occurred in metapelites, which the degree of deformation is various within the entire area; the third phase of deformation is marked by the locally developed kinked zone. There are various minerals in metapelites. The main minerals are sericite, muscovite, biotite, chlorite, garnet, staurolite, quartz, silliminate and feldspar, but kyanite, andalusite, cordierite, chloritoid and corundum can be found only by accident. Judged from the field observing and surveying, the extension of kyanite and staurolite distributed along the strike of strata indicates that the composition of the original rocks is the main controlling factor in their formation. The relations among metamorphic minerals, and between the metamorphism and deformation of the metapelites are very complex, they provide the important evidences for studying the evolution history of metamorphism and sequence of metamorphism and deformation in the area.
AN:  1996-060468

Record 164 of 393 in GeoRef Disc 4: 1993-1996

TI:  Corundum from thermally metamorphosed and hydrothermally altered Cambrian tuffaceous rocks, Bedkowska Valley, S Poland.
AU:  Koszowska-Ewa; Wolska-Anna
SO:  Mineralogia Polonica. 25; 1, Pages 29-42. 1994. 
PB:  Polskie Towarzystwo Mineralogiczne. Warsaw, Poland. 1994.
PY:  1994
AN:  1997-046364

Record 165 of 393 in GeoRef Disc 4: 1993-1996

TI:  Ruby/ sapphire corundum- Cr-silicate rocks; metasomatic products of greywacke schist and serpentinite, Southern Alps.
AU:  Grapes-Rodney-H
BK:  In: Geological Society of New Zealand 1994 annual conference; programme and abstracts.
BA:  Neil-Helen (editor); Gillespie-Jeanette-L (editor); Moon-Vicki (editor); Briggs-Roger (editor)
SO:  Geological Society of New Zealand Miscellaneous Publication. 80A; Pages 76. 1994. 
PB:  Geological Society of New Zealand. Christchurch, New Zealand. 1994.
PY:  1994
AN:  1997-060815

Record 166 of 393 in GeoRef Disc 4: 1993-1996

TI:  Ultramafic knockers and Cr-bearing minerals in marbles of central Rhodope (N. Greece) and their significance for the age of sedimentation.
AU:  Liati-A
BK:  In: Proceedings, 7th congress of the Geological Society of Greece, with emphasis on the geology of Macedonia and Thrace.
BA:  Mountrakis-D (chairperson)
SO:  Deltio tes Ellenikes Geologikes Etaireias = Bulletin of the Geological Society of Greece. 30; 3, Pages 155-164. 1994. 
PB:  Ellenike Geologike Etaireia. Athens, Greece. 1994.
PY:  1994
AB:  Ultramafic rocks occur in form of cm- to dm-large knockers incorporated in marbles of the upper tectonic unit of central Rhodope, near the contact with the Oligocene granodiorite of Xanthi. They have suffered regional metamorphism and were subsequently affected by contact metamorphism. The following mineral assemblage was identified in these rocks: olivine - serpentine - Cr-spinel - clinopyroxene + or - phlogopite + or - andradite + or - magnetite + or - calcite. Within the same marble belt, Cr-bearing minerals occur in a horizon of impure aluminous marbles, near the village Stirigma. These marbles bear the mineral assemblage: calcite + or - dolomite - zoisite - anorthite - Ca-amphibole - Cr-Al-spinel - Mg-spinel - chlorite + or - corundum + or - margarite + or - olivine + or - phlogopite. Besides Cr-Al-spinel, which is believed to be of detritic origin, also zoisite, corundum and amphibole are rich in Cr. The presence of ultramafic knockers and Cr-bearing minerals, among which detritic Cr-Al-spinel, indicates that during the time of sedimentation a source of ultrabasic rocks should have existed in the neighbouring regions. Since no pre-Triassic ophiolite complexes have been confirmed in the broad area surrounding Greece, the age of the carbonate sediments of central Rhodope, which contain the ultrabasic material may be interpreted as younger than Triassic.
AN:  1999-057302

Record 167 of 393 in GeoRef Disc 4: 1993-1996

TI:  Petrogenesis of red corundum rocks from the northern Dabie Mountains, Anhui, China.
AU:  Sun-Xianru; Zhou-Zuozhen
SO:  Yanshi Xuebao = Acta Petrologica Sinica. 10; 3, Pages 275-289. 1994. 
PB:  Science Press. Beijing, China. 1994.
PY:  1994
AN:  1999-058116

Record 168 of 393 in GeoRef Disc 4: 1993-1996

TI:  Reaction textures in a spinel-sapphirine granulite from the Eastern Ghats, India, and their implications.
AU:  Dasgupta-Somnath; Ehl-Juergen
SO:  European Journal of Mineralogy. 5; 3, Pages 537-543. 1993. 
PB:  Schweizerbart'sche Verlagsbuchhandlung (Naegele u. Obermiller). Stuttgart, Federal Republic of Germany. 1993.
PY:  1993
AN:  1993-017381

Record 169 of 393 in GeoRef Disc 4: 1993-1996

TI:  Reversal of the metastable kyanite + corundum + quartz and andalusite + corundum + quartz equilibria and the enthalpy of formation of kyanite and andalusite.
AU:  Harlov-Daniel-E; Newton-Robert-C
SO:  American Mineralogist. 78; 5-6, Pages 594-600. 1993. 
PB:  Mineralogical Society of America. Washington, DC, United States. 1993.
PY:  1993
AN:  1993-019715

Record 170 of 393 in GeoRef Disc 4: 1993-1996

TI:  Exsolution of garnet within clinopyroxene of mantle eclogites; major- and trace-element chemistry.
AU:  Jerde-Eric-A; Taylor-Lawrence-A; Crozaz-Ghislaine; Sobolev-Nikolai-V
SO:  Contributions to Mineralogy and Petrology. 114; 2, Pages 148-159. 1993. 
PB:  Springer International. Heidelberg-New York, International. 1993.
PY:  1993
AN:  1993-023601

Record 171 of 393 in GeoRef Disc 4: 1993-1996

TI:  Impact-induced phase transformations at 50-60 GPa in continental crust; an EPMA and ATEM study.
AU:  Martinez-Isabelle; Schaerer-Urs; Guyot-Francois
SO:  Earth and Planetary Science Letters. 119; 1-2, Pages 207-223. 1993. 
PB:  Elsevier. Amsterdam, Netherlands. 1993.
PY:  1993
AB:  Strongly shocked gneiss fragments from the allochthonous polymict breccia of the 23 Ma old Haughton impact crater were studied by optical microscopy, electron probe microanalysis (EPMA) and analytical transmission electron microscopy (ATEM). The study is focused on the substantiation of shock-induced phase transformations in rock-forming minerals, and their implications for post-shock thermal regimes and impact age dating. In the gneiss fragments, the original layering is largely preserved, although all the minerals have experienced dramatic phase transformations. Chemically, the various shock-generated decomposition regions still reflect the pre-shock mineralogy. However, significant heterogeneities exist on the 10-100 mu m scale. Four different regions of decomposition products can be distinguished (EPMA): (1) shocked biotite-rich regions with strong variations in Si, Al, K, Fe and Mg on the 10 mu m scale, (2) shocked quartz with about 3% Al and K and traces of Fe and Mg, (3) a region with Al/Si nearly equal 1, which does not correspond to any pre-shock mineral, and (4) shocked K-feldspar showing a significant deficit in K, and traces of Fe and Mg. On the nanometer scale, a uniform, bimodal reaction pattern emerges: all minerals are transformed to new crystals embedded in a silica-rich glass. The shock-generated crystals are: (1) spinel in shocked biotite, (2) alpha -quartz, cristobalite, and coesite in shocked quartz, (3) an unknown polymorph of corundum (Al (sub 2) O (sub 3) ) in feldspar and in the Al/Si nearly equal 1 region, and (4) mullite in association with SiO (sub 2) glass in shocked sillimanite grains. All crystals range in size between 0.05 and 1.0 mu m. Taking into account estimated durations and pressure-temperature conditions for shock-wave passage and post-shock temperatures, the reactions observed can be ascribed to high temperatures during and after pressure release. The different mineral-glass parageneses suggest temperatures in excess of 1400 degrees C. Moreover, given the small size of the newly formed minerals, very rapid cooling down to 1200 degrees C is required.
AN:  1993-033660

Record 172 of 393 in GeoRef Disc 4: 1993-1996

TI:  The role of ultramafic rocks in regulating the concentrations of volatile and non-volatile components during deep crustal metamorphism.
AU:  Rosing-Minik-T; Rose-Nicholas-M
BK:  In: Fluid-rock interaction in the deeper continental lithosphere.
BA:  Touret-Jacques-L-R (editor); Thompson-Alan-B (editor)
SO:  Chemical Geology. 108; 1-4, Pages 187-200. 1993. 
PB:  Elsevier. Amsterdam, Netherlands. 1993.
PY:  1993
AB:  The common preservation of H (sub 2) O and CO (sub 2) bearing phases in high grade ultramafic rocks indicates that they represent reservoirs of volatile components in the deep crust. The upper thermal stabilities of volatile bearing Mg-silicates and magnesite exceed those of volatile bearing phases in most other crustal lithologies. The solubility of many rock-forming components (e.g. CO (sub 2) , Al (sub 2) O (sub 3) , CaO, SiO (sub 2) ) is considerably lower in fluids coexisting with ultramafic rocks than in adjacent quartzo-feldspathic units. Metamorphism of crustal sections that include ultramafic rocks is accompanied by metasomatic reactions that regulate the chemistry of both volatile and non-volatile components in deep crustal metamorphic fluids. During amphibolite facies metamorphism, ultramafic rocks can absorb and store volatile and non-volatile components introduced from the country rock under conditions of low activities or fugacities. An example is the early fixation of CO (sub 2) , H (sub 2) O and aluminium by reaction of dunite to form chlorite, magnesite and progressively more siliceous Mg-silicates along an early low X CO (sub 2) reaction path. One-dimensional continuum models of fluid transport and reaction indicate that infiltration of fluids derived from quarzo-feldspathic country rocks can cause enrichment of aluminium in ultramafic rocks up to the level of wt.%. Internal reaction between the metasomatic minerals within ultramafic units release fluids during prograde metamorphism. Fluids will be released in two pulses; one with intermediate X CO (sub 2) and aluminium activity at the level of aluminosilicate or corundum saturation and a later pulse of pure CO (sub 2) .
AN:  1993-034007

Record 173 of 393 in GeoRef Disc 4: 1993-1996

TI:  Metamorphic petrology of the Froland corundum-bearing rocks; the cooling and uplift history of the Bamble Sector, South Norway.
AU:  Nijland-T-G; Liauw-F; Visser-D; Maijer-C; Senior-A
SO:  Bulletin - Norges Geologiske Undersokelse. 424; Pages 51-63. 1993. 
PB:  Universitetsforlaget. Trondheim - Oslo, Norway. 1993.
PY:  1993
AN:  1994-003730

Record 174 of 393 in GeoRef Disc 4: 1993-1996

TI:  Geology of the lamproites in Majiang, Guizhou.
AU:  Ren-Huaixiang; Zhang-Guangwen
SO:  Guizhou Dizhi = Geology of Guizhou. 10; 3, Pages 189-191. 1993. 
PB:  Editorial Department of Geology of Guizhou. Guiyang, China. 1993.
PY:  1993
AB:  40 lamproite bodies including five lamproite volcanic pipes were found in Majiang County of Guizhou province in 1992. These lamproites tectonically in the transition between the Jiangnan Uplift and the South Guizhou Depression occur in the mid-upper Cambrian, these rocks display porphyritic, metasomatic and corona fextures and their structures are mainly massive. The minerals composed of the rocks are mica, olivine, pyroxene, chromite, ilmenite, anatase, moissanite, apatite, perovsckite, corundum, retile, hypersthene, garnet, zircon, monazite, tournaline and so on. Chemical analyses of the lamproites show these rocks are bias-alkali to ultrabasic ones, named as olivine-lamproites with quite high content of REE. The study of the mineralization in this type of rocks is currently in progress.
AN:  1994-017345

Record 175 of 393 in GeoRef Disc 4: 1993-1996

TI:  Aluminas in Quaternary sedimentary rocks of Yakutia; new findings concerning mineral formation in permafrost regions.
AU:  Siegert-Christine
BK:  In: Permafrost; sixth international conference proceedings.
BA:  Cheng-Guodong (chairperson)
SO:  International Conference on Permafrost, Proceedings. 6, Vol. 1; Pages 569-573. 1993. 
PB:  [publisher varies]. [location varies], International. 1993.
PY:  1993
AN:  1995-037928

Record 176 of 393 in GeoRef Disc 4: 1993-1996

TI:  Kyanite solubility in H (sub 2) O at 700 degrees C and 1 GPa and Al transport during subduction zone metasomatism.
AU:  Manning-C-E
BK:  In: AGU 1993 spring meeting.
BA:  Anonymous
SO:  Eos, Transactions, American Geophysical Union. 74; 16, Suppl., Pages 321-322. 1993. 
PB:  American Geophysical Union. Washington, DC, United States. 1993.
PY:  1993
AN:  1997-007800

Record 177 of 393 in GeoRef Disc 3: 1985-1992

TI:  Mineralogy and petrology of margarite-corundum schists from the Charlotte Belt, York County, South Carolina.
AU:  Ranson-William-A; Stuart-Ashley-B
BK:  In: 41st annual meeting of the Southeastern Section of the Geological Society of America.
BA:  Anonymous
SO:  Abstracts with Programs - Geological Society of America. 24; 2, Pages 59. 1992. 
PB:  Geological Society of America (GSA). Boulder, CO, United States. 1992.
PY:  1992
AN:  1992-036704

Record 178 of 393 in GeoRef Disc 3: 1985-1992

TI:  Petrology of aluminous schist in the Boehls Butte region of northern Idaho; phase equilibria and P-T evolution.
AU:  Grover-Timothy-W; Rice-Jack-M; Carey-J-William
SO:  American Journal of Science. 292; 7, Pages 474-507. 1992. 
PB:  Kline Geology Laboratory, Yale University. New Haven, CT, United States. 1992.
PY:  1992
AN:  1992-041080

Record 179 of 393 in GeoRef Disc 3: 1985-1992

TI:  Metamorphic reactions in ruby corundum amphibolite from the Chunky Gal Mountain mafic-ultramafic complex, Clay County, North Carolina.
AU:  Ranson-William-A; Garihan-John-M; Ulmer-Katherine-E
BK:  In: Geological Society of America, 1992 annual meeting.
BA:  Anonymous
SO:  Abstracts with Programs - Geological Society of America. 24; 7, Pages 265. 1992. 
PB:  Geological Society of America (GSA). Boulder, CO, United States. 1992.
PY:  1992
AN:  1993-003783

Record 180 of 393 in GeoRef Disc 3: 1985-1992

TI:  Oxygen and magnesium isotopic compositions of corundum and hibonite grains from the Murchison Meteorite.
AU:  Amari-Sachiko; Zinner-Ernst; Lewis-Roy-S
BK:  In: 55th annual meeting, Meteoritical Society.
BA:  Anonymous
SO:  Meteoritics. 27; 3, Pages 198. 1992. 
PB:  Arizona State University, Center for Meteorite Studies. Tempe, AZ, United States. 1992.
PY:  1992
AN:  1994-009999

Record 181 of 393 in GeoRef Disc 3: 1985-1992

TI:  Presolar (?) corundum in the Orgueil Meteorite.
AU:  Huss-G-R; Hutcheon-I-D; Wasserburg-G-J; Stone-J
BK:  In: Abstracts of papers submitted to the Twenty-third lunar and planetary science conference.
BA:  Anonymous
SO:  Abstracts of Papers Submitted to the Lunar and Planetary Science Conference. 23; Pages 563-564. 1992. 
PB:  Lunar and Planetary Science Conference. Houston, TX, United States. 1992.
PY:  1992
AN:  1995-033469

Record 182 of 393 in GeoRef Disc 3: 1985-1992

TI:  Les chlorures en solution hydrothermale; solubilite et complexation des metaux (Al et Fe), modelisation des interactions avec les roches
Translated Title:  Chlorides in hydrothermal solutions; solubility and complexing of metals (Al and Fe), modelling of interactions with rocks.
AU:  Pascal-M-L; Volfinger-M; Roux-J; Clavieres-V
BK:  In: Programme dynamique et bilans de la Terre; resultats des travaux 1988-1992
Translated Title:  Earth dynamics and balances program; research results for 1988-1992.
BA:  Anonymous
PB:  Inst. National Sci. Univers, Centre National. Paris, France. 1992.
PY:  1992
AN:  1996-061672

Record 183 of 393 in GeoRef Disc 3: 1985-1992

TI:  Aluminium silicate xenocrystals in the "ophites" of the Subbetic Zone (southern Spain).
AU:  Morata-D; Puga-E
SO:  Schweizerische Mineralogische und Petrographische Mitteilungen = Bulletin Suisse de Mineralogie et Petrographie. 72; 3, Pages 379-387. 1992. 
PB:  Staeubli Verlag AG. Zurich, Switzerland. 1992.
PY:  1992
AB:  In one of numerous basic intrusions in the Triassic Keuper facies of the Betic Cordilleras a picritic dolerite was found. Evidence of gravity accumulation processes could be observed in this outcrop showing rocks which commonly contain crystalline aggregates of corundum+green spinel+highly sericitized plagioclase. These are pseudomorphs after andalusite. The dolerite has a high content of incompatible elements. The observations suggest a continental setting of the magmatism i.e. metapelites belonging to basement rocks (not found in the outcrops) have been assimilated by the magma.
AN:  1998-013770

Record 184 of 393 in GeoRef Disc 3: 1985-1992

TI:  The corundum garnetite in Zhimafang, Donghai District, China.
AU:  Fan-Qicheng; Liu-Ruoxin; Ma-Baolin; Yan-Fenglin
SO:  Yanshi Xuebao = Acta Petrologica Sinica. 8; 3, Pages 291-295. 1992. 
PB:  Science Press. Beijing, China. 1992.
PY:  1992
AB:  The corundum garnetite of Zhimafang, Donghai District is composed of red corundum (15 approximately 30%), garnet (65 approximately 80%) and little amount (<5%) of metasomatic genetic apatite, amphibole etc., and the REE pattern with high enrichment of LREE ((La)N = 1258) and strong diversity of LREE and HREE (La/Yb)= 126). It is inferred that corundum garnetite may have been formed during the collision of Yangzi Plate and North China Plate, through the high pressure metamorphism of Al rich-clay rocks and Mg rich-dolomite and the metasomatism of fluid rich in P, Na, LREE and volatiles.
AN:  1999-058203

Record 185 of 393 in GeoRef Disc 3: 1985-1992

TI:  An ion microprobe study of corundum in the Murchison Meteorite; implications for (super 26) Al and (super 16) O in the early solar system.
AU:  Virag-Alois; Zinner-Ernst-K; Amari-Sachiko; Anders-Edward
SO:  Geochimica et Cosmochimica Acta. 55; 7, Pages 2045-2062. 1991. 
PB:  Pergamon. Oxford, International. 1991.
PY:  1991
AN:  1991-038325

Record 186 of 393 in GeoRef Disc 3: 1985-1992

TI:  Petrology and fluid inclusions in garnetiferous gneisses and charnockites from Weddagala (Ratnapura District, Sri Lanka).
AU:  De-Maesschalck-A-A; Touret-J-L-R; Maaskant-P; Dahanayake-K
SO:  Journal of Geology. 99; 3, Pages 443-456. 1991. 
PB:  University of Chicago Press. Chicago, IL, United States. 1991.
PY:  1991
AN:  1991-038662

Record 187 of 393 in GeoRef Disc 3: 1985-1992

TI:  Petrology and mineralogy of quasi-whiteschist in the high-pressure metamorphic belt of the continental crust in Eastern China.
AU:  Liu-Yaqin; Zhang-Shuye; Qiao-Lanyong
SO:  Dizhi Lunping = Geological Review. 37; 4, Pages 348-355. 1991. 
PB:  [Geological Society of China]. Beijing, China. 1991.
PY:  1991
AB:  The high-pressure metamorphic belt of the continental crust in central China consists of blueschist, ecologite and quasi-whiteschist. Quasi-whiteschist is a rock type which contains abundant high-Al minerals. It occurs in the Middle Proterozoic. Metamorphic minerals include kyanite, corundum, topaz, paragonite, chloritoid and muscovite. The conditions of formation are P = 2000 MPa and T = 850-900 degrees C. It is metapelitic rocks formed under high-pressure conditions. Typical mineral associations are Ky+Tz+Q, Ky+Co and Ky+Pa+Mus. The associations are slightly different from typical whiteschist (Ky+Tc) termed by Schreyer, but their geological significance is similar. There are both metapelitic rocks formed under the high-pressure conditions and regarded as an indicator suggesting that crustal materials have been subducted to the mantle depths. Therefore the Al-rich rocks in central China is named quasi-whiteschists.
AN:  1992-008629

Record 188 of 393 in GeoRef Disc 3: 1985-1992

TI:  Experimental determination of the andalusite-corundum-quartz equilibrium.
AU:  Peterson-D-E; Newton-R-C
BK:  In: AGU-MSA 1991 spring meeting.
BA:  Anonymous
SO:  Eos, Transactions, American Geophysical Union. 72; 17, Pages 315. 1991. 
PB:  American Geophysical Union. Washington, DC, United States. 1991.
PY:  1991
AN:  1992-045301

Record 189 of 393 in GeoRef Disc 3: 1985-1992

TI:  Lamproitopodbnyye porody zapadnoy chasti sredinnogo Tyan'-Shanya
Translated Title:  Lamproite-like rocks from western middle Tien Shan.
AU:  Novgorodova-M-I; Galuskin-Ye-V; Yeremeyev-N-V; Sapozhnikova-Ye-N
BK:  In: Lamproity
Translated Title:  Lamproites.
BA:  Bogatikov-O-A (editor); Kononova-V-A (editor)
SO:  Pages 114-160. 1991. 
PB:  Izd. Nauka. Moscow, USSR. 1991.
PY:  1991
AN:  1993-024692

Record 190 of 393 in GeoRef Disc 3: 1985-1992

TI:  Study of alteration minerals in the secondary quartzite type of nonmetallic deposits in southeastern China.
AU:  Wu-Quanhuai; Chen-Henian; Zhang-Yaofu; Jiang-Yaohui
SO:  Bulletin of the Nanjing Institute of Geology and Mineral Resources, Chinese Academy of Geological Sciences = Nan-Ching Ti Chih K'uang Ch'an Yen Chiu So So K'an. 12; 4, Pages 72-86. 1991. 
PB:  Nanjing Institute of Geology and Mineral Resources, Chinese Academy of Geological Sciences. Nanjing, China. 1991.
PY:  1991
AN:  1993-037601

Record 191 of 393 in GeoRef Disc 3: 1985-1992

TI:  Aluminum-26; a non-uniform heat source in the early solar system.
AU:  Virag-Alois; Anders-Edward; Zinner-Ernst; Lewis-Roy-S
BK:  In: Twenty-second lunar and planetary science conference; abstracts of papers submitted.
BA:  Ryder-Graham (editor); Sharpton-Virgil-L (editor)
SO:  Abstracts of Papers Submitted to the Lunar and Planetary Science Conference. 22; Pages 1447-1448. 1991. 
PB:  Lunar and Planetary Science Conference. Houston, TX, United States. 1991.
PY:  1991
AN:  1993-045479

Record 192 of 393 in GeoRef Disc 3: 1985-1992

TI:  Corundum in the continental Upper Cretaceous sandstone in southern Bohemia, its composition, provenance and dissolution.
AU:  Vrana-S
SO:  Casopis pro Mineralogii a Geologii. 36; 4, Pages 237-242. 1991. 
PB:  Societas Mineralogica et Geologica Bohemoslovaca. Prague, Czech Republic. 1991.
PY:  1991
AN:  1994-014325

Record 193 of 393 in GeoRef Disc 3: 1985-1992

BK:  Origin and implication of corona structures within diabase dykes intruding the Archean orthogneisses of the central Grenville Province, east of Chibougamau, Quebec.
BA:  Madore-Catherine
PY:  1991
DG:  Master's
DI:  University of Ottawa. Ottawa, ON, Canada. Pages: 359. 1991.
AB:  Geological mapping has defined a distinct group of NNE trending diabase dykes east of the Grenville Front in the Chibougamau area. These dykes are found intruding Archean orthogneisses within a narrow zone, the Parautochthonous terrane, bounded to the northwest by the Grenville Front and to the southeast by the Allochthon Front. The best preserved dykes, exhibiting primary igneous minerals and textures, are located along the Grenville Front, whereas the most metamorphosed dykes (i.e. amphibolites) are located along the Allochthon Front. The dykes are tholeiitic to weakly alkaline and can be divided into four main groups, based on texture and certain major and trace elements: 1) low-TiO (sub 2) (average TiO (sub 2) 1.19 wt%, K (sub 2) O 0.45 wt%, P (sub 2) O (sub 5) 0.13 wt%, Y 18ppm, Zr 92ppm, Yb 1.8ppm), 2) high-TiO (sub 2) (average TiO (sub 2) 2.24 wt%, K (sub 2) O 0.82 wt%, P (sub 2) O (sub 5) 0.33 wt%, Y 34ppm, Zr 176ppm, Yb 3.3 ppm), 3) high-TiO (sub 2) segregations (average TiO (sub 2) 2.63 wt%, K (sub 2) O 0.97 wt%, P (sub 2) O (sub 5) 0.58 wt%, Y 51ppm, Zr 241ppm, Yb 5.1ppm) and 4) high-Al (sub 2) O (sub 3) (average A1 (sub 2) O (sub 3) 23.3 wt%, TiO (sub 2) 0.27 wt%, K (sub 2) O 0.37 wt%, P (sub 2) O (sub 5) 0.04 wt%, Y 7ppm, Zr 34ppm, Yb 0.8ppm). The low-TiO (sub 2) dykes are similar to N-type MORB and to low-TiO (sub 2) flood basalts, whereas the high-TiO (sub 2) diabase dykes and high-TiO (sub 2) pegmatoidal segregations are similar to high- Fe-Ti, continental flood basalts. Comparison of the dykes with other dyke swarms of the Grenville and Superior Provinces shows that the high-TiO (sub 2) group is most similar to the Grenville dyke swarm. The high-Al (sub 2) O (sub 3) group, characterized also by high Mg number and Ni contents, are similar to high-Al (sub 2) O (sub 3) basalts; however, they are considered to be cumulate rocks. Igneous minerals include olivine, augite, plagioclase, magnetite, biotite, and pargasite. Igneous biotite forms single corona layers around primary magnetite and pargasite occurs at olivine-magnetite and olivine-plagioclase contacts. These early formed corona layers are interpreted as products of late- to post-magmatic equilibration with a fluid phase at grain boundaries. The chemical composition of primary (igneous) mineral assemblages are for the most part not pristine because of reaction and recrystallization during the formation of post-magmatic corona structures. The olivine composition is overall uniform and ranges from Fo (sub 45) to Fo (sub 60) . Igneous clinopyroxene varies from En (sub 40) Wo (sub 39) Fs (sub 21) to En (sub 44) Wo (sub 39) Fs (sub 17) . Plagioclase composition ranges from An (sub 50) to An (sub 60) . Primary biotite flakes are uniform in composition with 3.14-3.19 wt% TiO (sub 2) , 14.45-15.09 wt% Al (sub 2) O (sub 3) , 2.87-3.31 wt% Fe (sub 2) O (sub 3) , 15.87-18.29 wt% FeO, and 11.49-14.38 wt% MgO. Post-magmatic amphiboles are pargasitic in composition with low TiO (sub 2) (0.02-0.18 wt%) and high Al (sub 2) O (sub 3) (17.0-21.0 wt%). The principal metamorphic minerals are enstatite, hornblende, spinel, corundum, garnet, albite, and quartz. The evolution from primary to secondary minerals can be followed through several complex reactions, four of which are: 1) olivine + plagioclase = enstatite + pargasiteCAl (sub 2) O (sub 3) , 2) olivine+0 (sub 2) = enstatite + magnetite, 3) pargasite + plagioclase = garnet + diopside + albite + Al (sub 2) O (sub 3) , 4) augite + plagioclase = pargasite, 5) biotite + plagioclase = garnet + pargasite + diopside. Reactions (1), (2), and (5) are spacially and temporaly associated. The orthopyroxene produced by reaction (1) is more magnesian-rich (En (sub 61-72) Fs (sub 27-39) ) than the orthopyroxene associated with magnetite crystals (En (sub 38-64) Fs (sub 36-62) ). Metamorphic clinopyroxene varies from salitic augitic to diopsidic in composition. Metamorphic plagioclase compositions are sodic, The chemical composition of ranging from An (sub 20) to An (sub 50) . Metamorphic amphibole is defined by high TiO (sub 2) (0.79-1.25 wt%) and low Al (sub 2) O (sub 3) (3.0-11.0 wt%) values. Garnet crystals produced during reaction (2) are magnesian-rich (Fe (sub 47-55) Mg (sub 16-22) Ca (sub 19-32) ) whereas garnet crystals from reaction (4) are iron-rich (Fe (sub 68-72) Mg (sub 7-11) Ca (sub 16-20) ). The development of metamorphic assemblages progressively increases from the Grenville Front to the Allochthon Front, where the dykes have been affected by the Grenvillian Orogeny to produce atoll garnet and hornblende. A tentative P-T path of corona reactions (based on several estimates of pressure and temperature from various geothermometers and geobarometers) across the parautochthonous terrane extends from 600 degrees C to 950 degrees C at 6.0 to 9.0 kbars.
AN:  1995-026497

Record 194 of 393 in GeoRef Disc 3: 1985-1992

TI:  Metastable growth of corundum adjacent to quartz in a spinel-bearing quartzite from the Archaean Napier Complex, Antarctica.
AU:  Motoyoshi-Y; Hensen-B-J; Matsueda-H
SO:  Journal of Metamorphic Geology. 8; 1, Pages 125-130. 1990. 
PB:  Blackwell. Oxford, United Kingdom. 1990.
PY:  1990
AN:  1990-016982

Record 195 of 393 in GeoRef Disc 3: 1985-1992

TI:  Peraluminous metamorphic rocks from the Namaqualand metamorphic complex (South Africa); geochemical evidence for an exhalation-related, sedimentary origin in a mid-Proterozoic rift system.
AU:  Willner-A; Schreyer-W; Moore-J-M
SO:  Chemical Geology. 81; 3, Pages 221-240. 1990. 
PB:  Elsevier. Amsterdam, Netherlands. 1990.
PY:  1990
AN:  1990-031248

Record 196 of 393 in GeoRef Disc 3: 1985-1992

TI:  Corundum-bearing garnet clinopyroxenites at Beni Bousera (Morocco); original plagioclase-rich gabbros recrystallized at depth within the mantle?.
AU:  Kornprobst-Jacques; Piboule-Michel; Roden-Michael; Tabit-Abdelhalim
SO:  Journal of Petrology. 31; 3, Pages 717-745. 1990. 
PB:  Clarendon Press. Oxford, United Kingdom. 1990.
PY:  1990
AN:  1990-044029

Record 197 of 393 in GeoRef Disc 3: 1985-1992

TI:  Variation of inorganic content of peat with depositional and ecological setting.
AU:  Raymond-Robert Jr.; Gladney-Ernest-S; Bish-David-L; Cohen-Arthur-D; Maestas-Lori-M
BK:  In: Recent advances in coal geochemistry.
BA:  Chyi-L-Lynn (editor); Chou-C-L (editor)
SO:  Special Paper - Geological Society of America. 248; Pages 1-12. 1990. 
PB:  Geological Society of America (GSA). Boulder, CO, United States. 1990.
PY:  1990
AN:  1990-060023

Record 198 of 393 in GeoRef Disc 3: 1985-1992

TI:  A staurolite-bearing corundum-garnet gneiss from the eastern Sor Rondane Mountains, Antarctica.
AU:  Asami-Masao; Grew-Edward-S; Makimoto-Hiroshi
BK:  In: Proceedings of the NIPR symposium on Antarctic geosciences.
BA:  Kaminuma-Katsutada (editor)
SO:  Proceedings of the NIPR Symposium on Antarctic Geosciences. 4; Pages 22-40. 1990. 
PB:  National Institute of Polar Research. Tokyo, Japan. 1990.
PY:  1990
AN:  1991-011442

Record 199 of 393 in GeoRef Disc 3: 1985-1992

TI:  Metabazity i giperbazity Susunayskogo khrebta (o. Sakhalin)
Translated Title:  Metabasites and ultrabasites of the Susunay Range, Sakhalin Island.
AU:  Bekhtol-d-A-F; Semenov-D-F
SO:  Tikhookeanskaya Geologiya = Pacific Geology. 1990; 1, Pages 121-126. 1990. 
PB:  Izdatel'stvo Nauka Tikhookeanskaya Geologiya. Novosibirsk, Russian Federation. 1990.
PY:  1990
AN:  1991-015961

Record 200 of 393 in GeoRef Disc 3: 1985-1992

TI:  Finding of staurolite in pelitic granulites from the Hidaka metamorphic belt, Hokkaido, Japan.
AU:  Osanai-Yasuhito; Owada-Masaaki
SO:  Chishitsugaku Zasshi = Journal of the Geological Society of Japan. 96; 7, Pages 549-552. 1990. 
PB:  Nippon Chishitsugaku Gakkai. Tokyo, Japan. 1990.
PY:  1990
AN:  1991-035288

Record 201 of 393 in GeoRef Disc 3: 1985-1992

TI:  Association of corundum, zircon, and plagioclase in alkaline basaltoids of Shavaryn-Tsaram (Mongolia).
AU:  Agafonov-L-V; Namsrai-T; Lkhamsuren-Zh; Pal-chik-N-A
SO:  Soviet Geology and Geophysics. 31; 9, Pages 72-77. 1990. 
PB:  Allerton Press. New York, NY, United States. 1990.
PY:  1990
AN:  1991-045830

Record 202 of 393 in GeoRef Disc 3: 1985-1992

TI:  The solubility of corundum in HF solutions at elevated temperatures.
AU:  Soboleva-Yu-B; Zaraisky-G-P-(Zarayskiy-G-P)
BK:  In: Experiment-89; informative volume.
BA:  Zharikov-V-A (editor)
SO:  Pages 77-78. 1990. 
PB:  Izd. Nauka. Moscow, USSR. 1990.
PY:  1990
AN:  1991-049594

Record 203 of 393 in GeoRef Disc 3: 1985-1992

TI:  Decouverte d'eclogites, de peridotites a spinelle et d'amphibolites a anorthite, spinelle et corindon dans le Morvan
Translated Title:  Discovery of eclogites, spinel-bearing peridotites, and anorthosite-bearing, spinel-bearing and corundum-bearing amphibolites in Morvan.
AU:  Godard-G
SO:  Comptes Rendus de l'Academie des Sciences, Serie 2, Mecanique, Physique, Chimie, Sciences de l'Univers, Sciences de la Terre. 310; 3, Pages 227-232. 1990. 
PB:  Gauthier-Villars. Montrouge, France. 1990.
PY:  1990
AN:  1994-023357

Record 204 of 393 in GeoRef Disc 3: 1985-1992

TI:  Los enclaves con espinela+corindon de los granitoides calcoalcalinos postectonicos
Translated Title:  Spinel+corundum enclaves of post-tectonic calc-alkaline granitoids.
AU:  Suarez-O; Arias-D; Corretge-L-G; Cuesta-A
BK:  In: Sociedad Espanola de Mineralogia; Reunion 10.
BA:  Anonymous
SO:  Boletin Sociedad Espanola de Mineralogia. 13; 1, 1990. 
PB:  Sociedad Espanola de Mineralogia. Madrid, Spain. Pages: 137. 1990.
PY:  1990
AN:  1995-000161

Record 205 of 393 in GeoRef Disc 3: 1985-1992

TI:  Sillimanite-corundum deposits of Sonapahar, Meghalaya, India; a metamorphosed Precambrian Paleosol.
AU:  Golani-P-R
SO:  Precambrian Research. 43; 3, Pages 175-189. 1989. 
PB:  Elsevier. Amsterdam, International. 1989.
PY:  1989
AN:  1989-045218

Record 206 of 393 in GeoRef Disc 3: 1985-1992

TI:  Speciation of Al, Si, and K in supercritical solutions; experimental study and interpretation.
AU:  Pascal-M-L; Anderson-G-M
SO:  Geochimica et Cosmochimica Acta. 53; 8, Pages 1843-1855. 1989. 
PB:  Pergamon. Oxford, International. 1989.
PY:  1989
AN:  1989-065531

Record 207 of 393 in GeoRef Disc 3: 1985-1992

TI:  Oxygen isotopic compositions of spinel and corundum grains from the Murchison carbonaceous chondrite.
AU:  Virag-Alois; Zinner-Ernst-K; Lewis-R-S; Amari-Sachiko
BK:  In: Abstracts for the 52nd annual meeting of the Meteoritical Society.
BA:  Koeberl-Christian (chairperson)
SO:  LPI Contribution. 712; Pages 249. 1989. 
PB:  Lunar and Planetary Institute. Houston, TX, United States. 1989.
PY:  1989
AN:  1989-073031

Record 208 of 393 in GeoRef Disc 3: 1985-1992

TI:  Corganites and corgaspinites; two new types of aluminous assemblages from the Jagersfontein kimberlite pipe.
AU:  Mazzone-P; Haggerty-Stephen-E
BK:  In: Kimberlites and related rocks.
BA:  Ross-J (editor); Jaques-A-L (editor); Ferguson-J (editor); Green-D-H (editor); O-Reilly-S-Y (editor); Danchin-R-V (editor); Janse-A-J-A (editor)
SO:  Special Publication - Geological Society of Australia. 14; 2, Pages 795-808. 1989. 
PB:  Geological Society of Australia. Sydney, N.S.W., Australia. 1989.
PY:  1989
AN:  1989-073508

Record 209 of 393 in GeoRef Disc 3: 1985-1992

TI:  The mineralogy, petrology and geochemistry of the Halfway Cove-Queensport Pluton, Nova Scotia, Canada.
AU:  Ham-L-J
BK:  In: Atlantic Geoscience Society; 1989 colloquium; abstracts.
BA:  Anonymous
SO:  Atlantic Geology. 25; 2, Pages 160-161. 1989. 
PB:  Atlantic Geoscience Society. Fredericton, NB, Canada. 1989.
PY:  1989
AN:  1990-004706

Record 210 of 393 in GeoRef Disc 3: 1985-1992

TI:  The stability of hercynite and hercynite-gahnite spinels in corundum- or quartz-bearing assemblages.
AU:  Shulters-Jacqueline-C; Bohlen-Steven-R
SO:  Journal of Petrology. 30; 4, Pages 1017-1031. 1989. 
PB:  Clarendon Press. Oxford, United Kingdom. 1989.
PY:  1989
AN:  1990-009309

Record 211 of 393 in GeoRef Disc 3: 1985-1992

TI:  Relative solubilities of corundum, gibbsite, boehmite, and diaspore at standard state conditions; an addendum.
AU:  Hemingway-Bruce-S; Kittrick-James-A; Peryea-F-J
SO:  Clays and Clay Minerals. 37; 6, Pages 566-567. 1989. 
PB:  Clay Minerals Society. Clarkson, NY, United States. 1989.
PY:  1989
AN:  1990-024589

Record 212 of 393 in GeoRef Disc 3: 1985-1992

BK:  The dissolution behavior of corundum, kaolinite, and andalusite; a surface complex reaction model for the dissolution of aluminosilicate minerals in diagenesis and weathering environs.
BA:  Carroll-Susan-Ann
PY:  1989
DG:  Doctoral
DI:  Northwestern Univ.. Evanston, IL, United States. Pages: 135. 1989.
AN:  1990-024850

Record 213 of 393 in GeoRef Disc 3: 1985-1992

TI:  Discovery of cosmic dust in granite and its geological significance.
AU:  Wang-Jijun; Zhuo-Zhaokun
SO:  Dizhi Lunping = Geological Review. 35; 6, Pages 492-499. 1989. 
PB:  [Geological Society of China]. Beijing, China. 1989.
PY:  1989
AB:  The Changli-Fuxin gold-and molybdenum-bearing granite belt is located in the NE-trending fracture belt between the Shanhaiguan-Yiwulu uplift and the Yanshan-Liaoning subsidence belt, which possesses 27 granite bodies (>5km2), including I-type, S-type and A-type. Although they belong to crustal granite, anatectic granite is dominant and metasomatic granite is subordinate. Four phases may be distinguished from the middle-later Inodsinian stage to late Yanshanian stage. Molybdenum in the granites was derived from the Archean basement, while lead and zinc occurring in the contact belt were derived from the country rocks of the Sinian. Cosmic dust has been discovered in eleven granite bodies of different stages and different types at Honglaoshan, Jinxi, Yangjiazhangzi, Jianchang, Yiwulu etc. There are three types of cosmic dust: silicate glass ball, ferruginous hollow ball and ferruginous solid ball. Cosmic dust is spherical, elliptical, spindle, milkdrop, dummbbell etc. in shape. The diameter of the cosmic dust ranges from 0.12 to 0.45mm and the thickness of the crust varies from 0.01 to 0.07mm. The surface of the cosmic dust is smooth with anasphaltic-semimetallic luster and strong magnetism, and is brittle. According to the electron microprobe, X-ray and microscopic analyses, the crust is composed mainly of magnetite and rhodonite with minor quartz and corundum. The grains of the magnetite are extremely fine (<0.004mm) and are arranged regularly in the shapes of snowflake-like, feather-like, imbricate and pilotaxitic arabesquitic crystallites. The core is composed of kanacite (alpha -Fe). Obviously, the cosmic dust in the granites was derived from the basement source rocks, and such rocks were bound to have been exposed at the surface once. Only then could the cosmic dust in the air have fallen on it, and then it descended to depth to undergo anataxis or metasomatism to form the granite. In this way, the cosmic dust has been kept as a refractory constituent in the granite. Therefore the existence of the cosmic dust in granite is the most direct and important evidence for the crustal granite.
AN:  1990-025232

Record 214 of 393 in GeoRef Disc 3: 1985-1992

TI:  O pozdney mineral'noy assotsiatsii korundovykh plagioklazitov Yugo-Zapadnogo Pamira (diaspor, korundofillit, margarit)
Translated Title:  Later mineral assemblages of corundum-anorthosites in the southwestern Pamirs; diaspore, corundophilite, margarite.
AU:  Litvinenko-A-K; Rossovskiy-L-N
SO:  Izvestiya Akademii Nauk Tadzhikskoy SSR. Otdeleniye Fiziko-Matematicheskikh, Khimicheskikh i Geologicheskikh Nauk. 1989; 2, Pages 46-51. 1989. 
PB:  Izdatel'stvo "Donish". Dushanbe, USSR. 1989.
PY:  1989
AN:  1990-055558

Record 215 of 393 in GeoRef Disc 3: 1985-1992

TI:  Cathodoluminescence mineralogy of meteorites.
AU:  Steele-Ian-M
BK:  In: Twentieth lunar and planetary science conference; abstracts.
BA:  Anonymous
SO:  Abstracts of Papers Submitted to the Lunar and Planetary Science Conference. 20, Part 3; Pages 1052-1053. 1989. 
PB:  Lunar and Planetary Science Conference. Houston, TX, United States. 1989.
PY:  1989
AN:  1990-057762

Record 216 of 393 in GeoRef Disc 3: 1985-1992

TI:  Vaporization in the system plagioclase solid solution-hydrogen.
AU:  Nagahara-H; Kushiro-I
BK:  In: Twentieth lunar and planetary science conference.
BA:  Anonymous
SO:  Abstracts of Papers Submitted to the Lunar and Planetary Science Conference. 20, Part 2; Pages 754-755. 1989. 
PB:  Lunar and Planetary Science Conference. Houston, TX, United States. 1989.
PY:  1989
AN:  1991-003135

Record 217 of 393 in GeoRef Disc 3: 1985-1992

TI:  Hydrothermal andalusite and corundum in a potassic alteration around a Proterozoic gabbro-tonalite-granite intrusion NE of Persberg, central Sweden.
AU:  Outhuis-J-H-M
SO:  Mineralogy and Petrology. 40; 1, Pages 1-16. 1989. 
PB:  Springer-Verlag. Vienna, Austria. 1989.
PY:  1989
AN:  1991-071899

Record 218 of 393 in GeoRef Disc 3: 1985-1992

TI:  Oxygen isotopic compositions of spinel and corundum grains from the Murchison carbonaceous chondrite.
AU:  Virag-A; Zinner-E; Lewis-R-S; Amari-S
BK:  In: Meteoritical Society, 52nd meeting; abstracts.
BA:  Wasson-John-T (editor)
SO:  Meteoritics. 24; 4, Pages 334. 1989. 
PB:  Arizona State University, Center for Meteorite Studies. Tempe, AZ, United States. 1989.
PY:  1989
AN:  1992-007037

Record 219 of 393 in GeoRef Disc 3: 1985-1992

TI:  Petrochemistry of eclogites from the Koidu kimberlite complex, Sierra Leone.
AU:  Hills-D-V; Haggerty-S-E
SO:  Contributions to Mineralogy and Petrology. 103; 4, Pages 397-422. 1989. 
PB:  Springer International. Heidelberg-New York, International. 1989.
PY:  1989
AN:  1993-039358

Record 220 of 393 in GeoRef Disc 3: 1985-1992

TI:  Petrologic and geochemical characteristics of Cenozoic volcanic rocks in the middle segment of the Tancheng-Lujiang fault zone.
AU:  Jin-Longyu
SO:  Yanshi Xuebao = Acta Petrologica Sinica. 1989; 4, Pages 45-57. 1989. 
PB:  Science Press. Beijing, China. 1989.
PY:  1989
AB:  According to the main rock-forming minerals, the Cenozoic volcanic rocks are mainly alkali olivine basalt, basanite and nephelinite. Among these rocks the alkali olivine basalt is most common, the nephelinite only occurs as a part of the volcanic rocks in the Qixia and Wudi regions. Some of alkalic basaltic rocks contain inclusions of spinel peridotite and garnet peridotite and megacrysts of Al-angite, anorthoclases, phlogopite, ilmenete, garnet and blue-corundum. OL' -Ne' -O', An-Ab' -Or and FeO*-FeO* / MgO Diagrams indicate that these rocks mainly belong to the alkali, the sub-alkali and rare tholeiite series. Transition metals of these rocks show highly fractionated distribution patterns. Their REE distribution patterns show higher LREE content relative to HREE with steep slope and delta Eu 0.94-1.10. The alkali olivine basalt, basanite and nephelinite in Qixia, Penglai and Wudidashan have higher REE abundance than those rocks in Linju-Changle and Yishui-Augou.
AN:  1999-058298

Record 221 of 393 in GeoRef Disc 3: 1985-1992

TI:  Magnesian staurolite in garnet-corundum rocks and eclogite from the Donghai District, Jiangsu Province, East China.
AU:  Enami-Masaki; Qijia-Zang
SO:  American Mineralogist. 73; 1-2, Pages 48-56. 1988. 
PB:  Mineralogical Society of America. Washington, DC, United States. 1988.
PY:  1988
AN:  1988-027956

Record 222 of 393 in GeoRef Disc 3: 1985-1992

TI:  Kornerupine-tourmaline reactions in paragneisses from West Greenland and southern Madagascar.
AU:  Ackermand-D; Windley-B-F; Herd-R-K; Razafiniparany-A
BK:  In: Geological Association of Canada, Mineralogical Association of Canada, Canadian Society of Petroleum Geologists, 1988 joint annual meeting--Association Geologique du Canada, Association Mineralogique du Canada, Societe Canadienne de Geologues Petroliers, 1988 reunion annuelle conjointe.
BA:  Anonymous
SO:  Program with Abstracts - Geological Association of Canada; Mineralogical Association of Canada; Canadian Geophysical Union, Joint Annual Meeting. 13; Pages A1. 1988. 
PB:  Geological Association of Canada. Waterloo, ON, Canada. 1988.
PY:  1988
AN:  1988-053596

Record 223 of 393 in GeoRef Disc 3: 1985-1992

TI:  Relative solubility of corundum, gibbsite, boehmite, and diaspore at standard state conditions.
AU:  Peryea-F-J; Kittrick-J-A
SO:  Clays and Clay Minerals. 36; 5, Pages 391-396. 1988. 
PB:  Clay Minerals Society. Clarkson, NY, United States. 1988.
PY:  1988
AN:  1988-078827

Record 224 of 393 in GeoRef Disc 3: 1985-1992

TI:  A chemical and isotopic study of hibonite-rich refractory inclusions in primitive meteorites.
AU:  Hinton-Richard-W; Davis-Andrew-M; Scatena-Wachel-Debra-E; Grossman-Lawrence; Draus-Ronald-J
SO:  Geochimica et Cosmochimica Acta. 52; 11, Pages 2573-2598. 1988. 
PB:  Pergamon. Oxford, International. 1988.
PY:  1988
AN:  1989-007090

Record 225 of 393 in GeoRef Disc 3: 1985-1992

TI:  Buchitic metagreywacke xenoliths from Mount Ngauruhoe, Taupo volcanic zone, New Zealand.
AU:  Graham-I-J; Grapes-R-H; Kifle-K
SO:  Journal of Volcanology and Geothermal Research. 35; 3, Pages 205-216. 1988. 
PB:  Elsevier. Amsterdam, Netherlands. 1988.
PY:  1988
AB:  Buchitic sedimentary xenoliths, a few centimetres to several decimetres diameter, occur in recent andesite from Mount Ngauruhoe, Tongariro Volcanic Centre, Taupo Volcanic Zone, New Zealand. Bulk chemistry and Sr isotope compositions of the xenoliths indicate that they are greywacke and argillite derived from Mesozoic Torlesse terrane basement that partly underlies the Taupo Volcanic Zone. The xenoliths contain up to 80% glass with quartz, apatite and zircon remaining as unmelted phases. Glasses within the xenoliths are peraluminous (A/CNK = 1.0-1.4), have high normative corundum (2-7%), appreciable FeO (2-4 wt.%), MgO (0.2-1.5 wt.%), TiO (sub 2) (0.17-0.84 wt.%), relatively high normative An (1.0-5.3%), and do not represent S-type granitic melts. In the argillite the glass has higher amounts of Al (sub 2) O (sub 3) , FeO, MgO, CaO and K (sub 2) O, and has less SiO (sub 2) and Na (sub 2) O than glass in the greywacke. Silica-rich glass (up to 80 wt.% SiO (sub 2) ) surrounds partially melted quartz. Variable glass chemistry reflects the heterogeneous (layered) nature of the xenoliths. Cordierite (Mg/(Mg+Fe+Mn)-0.78-0.58), orthopyroxene (En 43-56), Mg-rich ilmenite, rutile, pleonaste, V-Cr-Ti spinel, and pyrrhotite occur in the glass of the xenoliths. The dominant cordierite, orthopyroxene, spinel assemblage can be accounted for by disequilibrium breakdown reactions under low oxidation conditions (QFM) involving phengite and chlorite which are abundant in Torlesse greywacke and argillite cropping out along the eastern side of the Taupo Volcanic Zone. Comparison with glass compositions and phase relations of disequilibrium melting experiments on Torlesse greywacke and argillite indicates a minimum temperature of 775 degrees C and a maximum pressure of 1.5 kbar for fusion of the xenoliths that underwent a rapid rate of heating at a depth of less than 5 km and a cooling period constrained by the time of quenching when they were erupted.
AN:  1989-021037

Record 226 of 393 in GeoRef Disc 3: 1985-1992

TI:  Corundum- and zoisite-bearing marbles in the Rhodope Zone, Xanthi Area (N. Greece); estimation of the fluid phase composition.
AU:  Liati-A
SO:  Mineralogy and Petrology. 38; 1, Pages 53-60. 1988. 
PB:  Springer-Verlag. Vienna, Austria. 1988.
PY:  1988
AN:  1989-024155

Record 227 of 393 in GeoRef Disc 3: 1985-1992

TI:  Prediction of the solubility of aluminium oxides and hydroxides at high temperature and pressure.
AU:  Castet-S; Anderson-G-M; Mesmer-R-E; Schott-J
BK:  In: International congress of geochemistry and cosmochemistry.
BA:  Bottinga-Yan (editor)
SO:  Chemical Geology. 70; 1-2, Pages 158. 1988. 
PB:  Elsevier. Amsterdam, Netherlands. 1988.
PY:  1988
AN:  1989-049528

Record 228 of 393 in GeoRef Disc 3: 1985-1992

TI:  Geology and the origin of the corundum bearing skarn at Bakamuna, Sri Lanka.
AU:  Silva-K-K-M-W; Siriwardena-C-H-E-R
SO:  Mineralium Deposita. 23; 3, Pages 186-190. 1988. 
PB:  Springer-Verlag. Berlin, Federal Republic of Germany. 1988.
PY:  1988
AN:  1989-059145

Record 229 of 393 in GeoRef Disc 3: 1985-1992

TI:  Corundum, Cr-muscovite rocks at O'Briens, Zimbabwe; the conjunction of hydrothermal desilification and LIL-element enrichment; geochemical and isotopic evidence; discussion and reply.
AU:  Schreyer-W; Kerrich-R; Fyfe-W-S; Barnett-R-L; Blair-B-B; Willmore-L-M
SO:  Contributions to Mineralogy and Petrology. 100; 4, Pages 552-559. 1988. 
PB:  Springer International. Heidelberg-New York, International. 1988.
PY:  1988
AN:  1989-067663

Record 230 of 393 in GeoRef Disc 3: 1985-1992

TI:  Experimentelle Untersuchung zum Mechanismus von Muskovitabbauenden Reaktionen
Translated Title:  Experimental studies on the mechanics of muscovite chemical reactions.
AU:  Grossmann-U; Metz-P; Wirth-R
BK:  In: Referate der Vortraege und Poster; 66. Jahrestagung der Deutschen Mineralogischen Gesellschaft.
BA:  Anonymous
SO:  Fortschritte der Mineralogie, Beiheft. 66; 1, Pages 48. 1988. 
PB:  E. Schweizerbart'sche Verlagsbuchhandlung. Stuttgart, Federal Republic of Germany. 1988.
PY:  1988
AN:  1989-067745

Record 231 of 393 in GeoRef Disc 3: 1985-1992

TI:  Ungewoehnliche Einschlussbilder in Korund- und Spinell-fuehrenden Paragenesen des Edelsteinlagerstaettenkomplexes Elahera, Sri Lanka
Translated Title:  Uncommon inclusions in corundum- and spinel-bearing parageneses of precious stone complexes of Elahera, Sri Lanka.
AU:  Malley-J; Pense-J; Dissanayake-C-B
BK:  In: Referate der Vortraege und Poster; 66. Jahrestagung der Deutschen Mineralogischen Gesellschaft.
BA:  Anonymous
SO:  Fortschritte der Mineralogie, Beiheft. 66; 1, Pages 100. 1988. 
PB:  E. Schweizerbart'sche Verlagsbuchhandlung. Stuttgart, Federal Republic of Germany. 1988.
PY:  1988
AN:  1989-067797

Record 232 of 393 in GeoRef Disc 3: 1985-1992

TI:  Geology, mineralogy and mineral resources of Sri Lanka.
AU:  Jayatileke-Sarath; Matsueda-Hiroharu
SO:  Journal of the Mining College, Akita University, Series A: Mining Geology. 7; 1, Pages 1-27. 1988. 
PB:  Akita Daigaku Kozangakubu. Akita, Japan. 1988.
PY:  1988
AN:  1990-001773

Record 233 of 393 in GeoRef Disc 3: 1985-1992

TI:  Experimental determination of corundum solubility and Al-speciation in supercritical H (sub 2) O-HCl solutions.
AU:  Baumgartner-Lukas-P; Eugster-Hans-P
BK:  In: Geological Society of America, 1988 centennial celebration.
BA:  Anonymous
SO:  Abstracts with Programs - Geological Society of America. 20; 7, Pages 191. 1988. 
PB:  Geological Society of America (GSA). Boulder, CO, United States. 1988.
PY:  1988
AN:  1990-011949

Record 234 of 393 in GeoRef Disc 3: 1985-1992

BK:  The mineralogy, petrology, and geochemistry of the Halfway Cove-Queensport Pluton, Nova Scotia, Canada.
BA:  Ham-Linda-J
PY:  1988
DG:  Master's
DI:  Dalhousie University. Halifax, NS, Canada. Pages: 294. 1988.
AB:  The Halfway Cove-Queensport Pluton (HCQP) of eastern Nova Scotia is a moderately deformed, post-Acadian granitoid intrusion that was emplaced into regionally deformed and metamorphosed Meguma Group metasedimentary rocks by passive stoping, with some degree of forceful emplacement. Deformation features (C-S fabrics) occur in the northern part of the body, closest to the Cobequid-Chedabucto fault zone, and within the southern part, closest to a postulated shear zone. The pluton is composed primarily of medium- to coarse-grained monzogranite, with minor granodiorite. Five rock units are recognized by textural and mineralogical characteristics (HCQP1, HCQP1A, HCQP2, HCQP3, HCQP4). There are minor late-stage intrusions of aplite, pegmatite and leucogranite. All rocks, except the late-stage intrusions, contain quartz, alkali feldspar, plagioclase, muscovite and biotite. Garnet is present as xenocrystic grains in monzogranite of some units, and as magmatic grains in late-stage aplites. Apatite occurrs in trace amounts, and cordierite is not present. This absence contrasts with other granitoid bodies of southwestern and south-central Nova Scotia (e.g. South Mountain Batholith and the Musquodoboit Batholith) where cordierite is common. The presence of garnet and muscovite, both of presumed magmatic origin, constrains the pressure of crystallization to between 3 and 4 kbars (10.5-14 km). Major element chemical analyses indicate that the rocks are peraluminous (i.e. Al (sub 2) O (sub 3) /CaO+Na (sub 2) O+K (sub 2) O) >1). Compositions resemble those of the Halifax Pluton, the Musquodoboit Batholith, and the granitoid plutons of central and eastern Nova Scotia (excluding the Liscomb Complex), with lower FeO (sub t) , TiO (sub 2) and higher Al (sub 2) O (sub 3) , P (sub 2) O (sub 5) and normative corundum than the South Mountain Batholith. The least evolved units of the HCQP, however, are chemically more similar to rocks of the South Mountain Batholith. A well-defined chemical break between the two least evolved units (HCQP1 and HCQP1A), and the three more evolved units (HCQP2, HCQP3 and HCQP4), suggests that, although some of the five units may be related by fractional crystallization, other processes such as assimilation and melting of heterogeneous sources may have contributed to the overall chemical variation in the HCQP. Major and trace element characteristics of the three more evolved units suggest that at least two of the units are co-magmatic. Rare earth element patterns of unit HCQP1 .
AN:  1990-053313

Record 235 of 393 in GeoRef Disc 3: 1985-1992

TI:  Perekhod kianita Al (sub 2) SiO (sub 5) v korund Al (sub 2) O (sub 3) +SiO (sub 2)
Translated Title:  Transition of Al (sub 2) SiO (sub 5) kyanite to corundum Al (sub 2) O (sub 3) +SiO (sub 2) .
AU:  Ponomarenko-A-I
SO:  Doklady Akademii Nauk SSSR. 303; 6, Pages 1446-1449. 1988. 
PB:  Akademiya Nauk SSSR. Moscow, Russian Federation. 1988.
PY:  1988
AN:  1994-007542

Record 236 of 393 in GeoRef Disc 3: 1985-1992

TI:  Eksperimental'noye issledovaniye preobrazovaniy boksitonosnykh kor vyvetrivaniya pri povyshennykh P (sub H2O) -T parametrakh
Translated Title:  Experimental investigations of transformation of bauxite-bearing weathering cores for increased P (sub H2O) -T parameters.
AU:  Kotov-N-V; Nikitina-A-P; Ivanov-V-P
BK:  In: Problemy issledovaniya i ispol'zovaniya glin i glinistykh mineralov
Translated Title:  Problems in the study and utilization of clays and clay minerals.
BA:  Seydov-A-G (editor)
SO:  Pages 180-190. 1988. 
PB:  Baku, Azerbaijan. 1988.
PY:  1988
AN:  1996-019415

Record 237 of 393 in GeoRef Disc 3: 1985-1992

TI:  The peraluminous granodiorites with low initial Sr-87/ Sr-86 ratio and their genesis in southern Anhui, China.
AU:  Zhou-Xinmin; Wang-Dezi
SO:  Yanshi Xuebao = Acta Petrologica Sinica. 1988; 3, Pages 36-44. 1988. 
PB:  Science Press. Beijing, China. 1988.
PY:  1988
AB:  In this paper the petrological, mineralogical, and isotopic aspects of three granitic intrusions in southern Anhui are discussed in detail. These three Precambrian granodiorite bodies are Xiuning (132km2), Xicun (133km2) and Xixian (32km2). The achievements of this paper are as following; 1, The authors found common presence of cordierite and Mn-poor almandite in these three bodies. The average values (13 samples) of A/CNK and norm corundum for whole rocks are 1.35 and 4.31, respectively. Consequently, it is confirmed that they are typical peraluminous granodiorites. Based on the coexisting relationship and chemistry of minerals, the data of thickness for Precambrian strata, and the melting experiment of peraluminous granite made by T. H. Green (1976, 1977), it is assumed that the initial crystallization of magma began at the depth approximately of 24 km in lower crust and emplaced at the depth of 8km+ in upper crust. 2, The value of the initial 87Sr/86Sr ratio for Xiuning granodiorite is 0.7039+-0.00033 (r = 0.99). Obviously, this value indicates that the parental rock of granodiorite is not a sort of Al-rich felsic sedimentary rock, but probably is intermediate-basic volcanic rocks and volcanic sedimentary deposits of ophiolite suite which are the intrusions nearby at present exposure. Because the ophiolite was the youngest crust without radioactive strontium in that geological time. It is likely that due to certain reason the young oceanic crust subducted towards the continent and partial melting took place later on. The resulting magma was peraluminous and preserved low 87Sr/86Sr initial ratio which is characteristic of original ophiolite suite. 3, The peraluminous granodiorites in southern Anhui are post-collision granitoid and bear no relation with volcanism and regional metamorphism. They might belong to a new type for the peraluminous granitoid. If the above viewpoint is correct, a simplified classification of the Precambrian granitoids in southern China into S-type and I-type or other current genetic types is incomplete.
AN:  1999-056128

Record 238 of 393 in GeoRef Disc 3: 1985-1992

TI:  Hydration of corundum-bearing xenoliths in the Qorqut granite complex, Godthaabsfjord, West Greenland.
AU:  Rosing-Minik-T; Bird-Dennis-K; Dymek-Robert-F
SO:  American Mineralogist. 72; 1-2, Pages 29-38. 1987. 
PB:  Mineralogical Society of America. Washington, DC, United States. 1987.
PY:  1987
AN:  1987-055728

Record 239 of 393 in GeoRef Disc 3: 1985-1992

TI:  Evidence for Devonian age of the Okpilak Batholith, northeastern Brooks Range, Alaska.
AU:  Dillon-J-T; Bakke-A-A
BK:  In: Geological Society of America, Cordilleran Section, 83rd annual meeting with the Paleontological Society of America, Pacific Coast Section.
BA:  Anonymous
SO:  Abstracts with Programs - Geological Society of America. 19; 6, Pages 373. 1987. 
PB:  Geological Society of America (GSA). Boulder, CO, United States. 1987.
PY:  1987
AN:  1987-080247

Record 240 of 393 in GeoRef Disc 3: 1985-1992

TI:  Corundum, Cr-muscovite rocks at O'Briens, Zimbabwe; the conjunction of hydrothermal desilicification and LIL-element enrichment; geochemical and isotopic evidence.
AU:  Kerrich-R; Fyfe-W-S; Barnett-R-L; Blair-B-B; Willmore-L-M
SO:  Contributions to Mineralogy and Petrology. 95; 4, Pages 481-498. 1987. 
PB:  Springer International. Heidelberg-New York, International. 1987.
PY:  1987
AN:  1988-009310

Record 241 of 393 in GeoRef Disc 3: 1985-1992

TI:  Accessory minerals in lamproite-like rocks from Central Asia.
AU:  Novgorodova-M-I; Galuskin-Ye-V; Boyarskaya-R-V; Mokhov-A-V
SO:  International Geology Review. 29; 3, Pages 295-306. 1987. 
PB:  Winston & Son. Silver Spring, MD, United States. 1987.
PY:  1987
AN:  1988-013215

Record 242 of 393 in GeoRef Disc 3: 1985-1992

TI:  Mineral chemistry and metasomatic growth of aluminous enclaves in gedrite-cordierite-gneiss from southwestern New Hampshire, USA.
AU:  Schumacher-John-C; Robinson-Peter
SO:  Journal of Petrology. 28; 6, Pages 1033-1073. 1987. 
PB:  Clarendon Press. Oxford, United Kingdom. 1987.
PY:  1987
AN:  1988-024226

Record 243 of 393 in GeoRef Disc 3: 1985-1992

TI:  Zur Entstehung Al-reicher oxidischer Mineralphasen in den Metasedimenten Sri Lankas
Translated Title:  Genesis of Al-rich oxide mineral phase in the metasediments of Sri Lanka.
AU:  Malley-J
BK:  In: Referate der Vortraege und Poster; 65. Jahrestagung der Deutschen Mineralogischen Gesellschaft
Translated Title:  Lectures and posters; 65th anniversary of the Deutschen Mineralogischen Gesellschaft.
BA:  Anonymous
SO:  Fortschritte der Mineralogie, Beiheft. 65; 1, Pages 129. 1987. 
PB:  E. Schweizerbart'sche Verlagsbuchhandlung. Stuttgart, Federal Republic of Germany. 1987.
PY:  1987
AN:  1988-029212

Record 244 of 393 in GeoRef Disc 3: 1985-1992

TI:  Petrography of a corundum-bearing compound Allende inclusion.
AU:  Kuehner-S-M; Grossman-L
BK:  In: Abstracts of papers presented at the 50th annual meeting; the Meteoritical Society.
BA:  Anonymous
SO:  Meteoritics. 22; 4, Pages 433-434. 1987. 
PB:  Arizona State University, Center for Meteorite Studies. Tempe, AZ, United States. 1987.
PY:  1987
AN:  1988-043070

Record 245 of 393 in GeoRef Disc 3: 1985-1992

TI:  Corundum+quartz association in Archean granulite-facies rock from Enderby Land, East Antarctica; preliminary interpretation.
AU:  Motoyoshi-Yoichi; Matsueda-Hiroharu
BK:  In: Proceedings of the NIPR symposium on Antarctic geosciences.
BA:  Matsuda-Tatsuro (editor)
SO:  Proceedings of the NIPR Symposium on Antarctic Geosciences. 1; Pages 107-112. 1987. 
PB:  National Institute of Polar Research. Tokyo, Japan. 1987.
PY:  1987
AN:  1988-062326

Record 246 of 393 in GeoRef Disc 3: 1985-1992

TI:  Novyye mineralo-geokhimicheskiye kriterii korundonosnosti mramorov na Yugo-Zapadnom Pamire
Translated Title:  New mineralogical and geochemical criteria of corundum-bearing marbles in the southwestern Pamirs.
AU:  Shamsi-Zade-A
SO:  Doklady Akademii Nauk Tadzhikskoy SSR. 1987; 6, Pages 378-382. 1987. 
PB:  Akademiya Nauk Tadzhikskoy SSR. Dushanbe, USSR. 1987.
PY:  1987
AN:  1988-076461

Record 247 of 393 in GeoRef Disc 3: 1985-1992

TI:  Geochemistry of muong nong type tektites; a review.
AU:  Koeberl-Christian
BK:  In: The 2nd international conference on natural glasses.
BA:  Jelinek-E (editor)
SO:  Abstracts - International Conference on Natural Glasses. 2; Pages 40. 1987. 
PB:  [publisher varies]. Prague, Czechoslovakia. 1987.
PY:  1987
AN:  1989-018253

Record 248 of 393 in GeoRef Disc 3: 1985-1992

TI:  Inclusiones en corindones sinteticos
Translated Title:  Inclusions in synthetic corundum.
AU:  Garzon-J
SO:  Boletin del Instituto Gemologico Espanol. 29; Pages 6-28. 1987. 
PB:  Instituto Gemologico Espanol. Madrid, Spain. 1987.
PY:  1987
AN:  1990-071736

Record 249 of 393 in GeoRef Disc 3: 1985-1992

TI:  Enclaves con espinela-corindon-sillimanita en rocas andesitico-daciticas (Noguera, Sierra de Albarracin Teruel)
Translated Title:  Inclusions with spinel-corundum-sillimanite in andesitic-dacitic rocks, Noguera, Sierra de Albarracin, Teruel.
AU:  Auque-L-F; Sanchez-Cela-V; Aparicio-A
SO:  Estudios Geologicos (Madrid). 43; 3-4, Pages 139-147. 1987. 
PB:  Consejo Superior de Investigaciones Cientificas, Instituto de Investigaciones Geologicas "Lucas Mallada". Madrid, Spain. 1987.
PY:  1987
AN:  1991-076198

Record 250 of 393 in GeoRef Disc 3: 1985-1992

TI:  The tin-granites and their relation to mineralization in Tengchong, Yunnan.
AU:  Mao-Jingwen; Zhang-Shilu; Rossi-P
SO:  Yanshi Xuebao = Acta Petrologica Sinica. 1987; 4, Pages 32-43. 1987. 
PB:  Science Press. Beijing, China. 1987.
PY:  1987
AB:  Lai lishan, Guyong and Tieyaostan granite bodies were taken as examples for discussing the inherent relation between tin-barren granite and tin granite in this paper through studying the characteristics of the mineralogy petrology and geochemistry. Based on the work mentioned above the origin, evolution of the granitoids associated with tin deposits and their relation to mineralization were discussed using the methods of isotopic geology. The main conclusions can be summed up as follows: 1. In rock series from granodiorite to monzonitic (syenite) granite mafic minerals decrease with increasing felsic minerals. In the meantime, or in k-feldspar increases and An in plagioclase decreases. The prominent feature k-feldspar and plagioclase in granodiorite is the well developed composition zonation. FM value of biotite increase. The evolutional tendency of its composition is noted with decrease of cesium down and increase of iron and aluminium the species of accessory minerals become diversified and more complex. At the same time Fe (super 2+) /Fe (super 3+) ratio of magnetite gradually decreases. 2. Both types of granitoids mentioned above belong to postaluminium granite series with corundum as the standard mineral ranging from 0.1 to 3.67. In the granite series from granodiorite to monzonite (syenite) silica-alkali component increases, while mafic, Al (sub 2) O (sub 3) , CaO content decreases. The latter had a evident feature of high differentiation with average index of 90.99, K/Rb = 68-91. However, for the former one the differentiation index is 81.69, K/Rb = 182.3. The evolutional tendency of the REE in the granitoids is that from an early to a late stage the total REE, LREE, delta Eu value decrease, while the HREE increase either in the granite bodies of different substages of in the rocks with different crystallization time in same granite body. In the rock series from granodiorite to monzonite (syenite) granite the REE evolution is controlled by the crystallization of plagioclase and other rock forming minerals. A group of accessories enriched in LREE affect the redistribution of the REE in the same monzonite (syenite) granite. 4. The results of Sm-Nd, Rb-Sr and O isotopes unanimously show that the compound granites in Tengchong originated from the crust as multi-substage products in the same stage. Gaoligong System were supposed to be their mother source. The origin of tin in the granite was related to the regional geochemistry. The multiple fractionation and evolution of the granitoids played a role in the formation of tin deposits. The collision between the Eurasian Plate and the Indian Plate was the leading factor for the granitic magmatism and the mineralization.
AN:  1999-056786

Record 251 of 393 in GeoRef Disc 3: 1985-1992

TI:  PERANORM; a BASIC program to calculate a modal norm for peraluminous granitoids.
AU:  Usdansky-Steven-I
SO:  Computers and Geosciences. 12; 1, Pages 13-20. 1986. 
PB:  Pergamon. New York-Oxford-Toronto, International. 1986.
PY:  1986
AN:  1986-050974

Record 252 of 393 in GeoRef Disc 3: 1985-1992

TI:  The generation of quartz-normative melts and corundum-bearing restites by crustal anatexis; petrogenetic modelling based on an example from the Lewisian of North-west Scotland.
AU:  Cartwright-I; Barnicoat-A-C
SO:  Journal of Metamorphic Geology. 4; 1, Pages 79-99. 1986. 
PB:  Blackwell. Oxford, United Kingdom. 1986.
PY:  1986
AN:  1986-057505

Record 253 of 393 in GeoRef Disc 3: 1985-1992

TI:  Inorganic contents of peats vary with depositional and ecological settings.
AU:  Raymond-Robert Jr.; Gladney-Ernest-S; Bish-David-L; Cohen-Arthur-D; Maestas-Lori-M
BK:  In: The Geological Society of America, North-Central Section, 20th annual meeting.
BA:  Heimlich-Richard-A (chairperson)
SO:  Abstracts with Programs - Geological Society of America. 18; 4, Pages 320. 1986. 
PB:  Geological Society of America (GSA). Boulder, CO, United States. 1986.
PY:  1986
AN:  1986-085157

Record 254 of 393 in GeoRef Disc 3: 1985-1992

TI:  A thermobarometer for corundum-bearing pelites.
AU:  Bohlen-Steven-R; Dietz-J-M; Zec-C-P; Governale-R-C
BK:  In: The Geological Society of America, 99th annual meeting.
SO:  Abstracts with Programs - Geological Society of America. 18; Pages 545. 1986. 
PB:  Geological Society of America (GSA). Boulder, CO, United States. 1986.
PY:  1986
AN:  1987-037566

Record 255 of 393 in GeoRef Disc 3: 1985-1992

TI:  A discussion on the genetic classification of metasomatites and their associated mineralizations.
AU:  Zhao-Yiming
SO:  Mineral Deposits = Kuangchuang Dizhi. 5; 4(18), Pages 1-13. 1986. 
PB:  Chinese Academy of Geological Sciences, Institute of Mineral Deposits. Beijing, China. 1986.
PY:  1986
AB:  A genetic classification of metasomatites is given is this paper. The six genetic types or groups of metasomatites adopted by the author are as follows: (1) metasmomatites related to intermediate, basic and ultrabasic magmatic rocks; (2) metasomatites associated with granitoids; (3) metasomatites connected with alkali intrusive rocks, alkali granites and ultrabasic alkali igneous rocks; (4) metasomatites bound up with hydrothermalism of migmatization; (5) metasomatites linked up with volcanic hydrothermalism and (6) metasomatites having nothing to do with magmatism. In each genetic type-group there exist several metasomatic formations. The author advances some new metasomatic formations, such as manganese calcic skarn, spinel-corundum-anorthoclasite and fluor-boro-metasomatites, and briefly describes characters of some important metasomatic formations which have rarely been mentioned in Chinese geological references. Finally, the term "metasomatic series" has been further illustrated.
AN:  1987-049254

Record 256 of 393 in GeoRef Disc 3: 1985-1992

TI:  Novyye proyavleniya korundovoy mineralizatsii v mramorakh Lyangarskogo rayona (Yugo-Zapadnyy Pamir)
Translated Title:  New manifestation of corundum mineralization in the Lyangar-district marbles; southwestern Pamirs.
AU:  Rossovskiy-L-N; Litvinenko-A-K
SO:  Doklady Akademii Nauk Tadzhikskoy SSR. 29; 7, Pages 422-425. 1986. 
PB:  Akademiya Nauk Tadzhikskoy SSR. Dushanbe, USSR. 1986.
PY:  1986
AN:  1987-067302

Record 257 of 393 in GeoRef Disc 3: 1985-1992

TI:  En korundforande anortosit i det Sydvastsvenska gnejskomplexet
Translated Title:  Corundum-bearing anorthosite of the southwestern Sweden gneiss complex.
AU:  Lindh-A
BK:  In: Abstracts, 17 (super e* Nordiska geologmotet, 1986
Translated Title:  Abstracts, 17th Nordic geological meeting, 1986.
BA:  Lang-Kaj (prefacer)
SO:  Pages 103. 1986. 
PB:  Helsingsfors Univ.. Helsinki, Finland. 1986.
PY:  1986
AN:  1987-084253

Record 258 of 393 in GeoRef Disc 3: 1985-1992

TI:  Occurrence of alluaudite from a peraluminous mineral-bearing pegmatite in Cino Villas (Basque Pyrenees, Navarra, Spain).
AU:  Pesquera-A; Fontan-F; Velasco-F
SO:  Neues Jahrbuch fuer Mineralogie. Monatshefte. 1986; 2, Pages 82-88. 1986. 
PB:  E. Schweizerbart'sche Verlagsbuchhandlung. Stuttgart, Federal Republic of Germany. 1986.
PY:  1986
AN:  1988-004708

Record 259 of 393 in GeoRef Disc 3: 1985-1992

TI:  Saphirine et staurotide riche en magnesium et chrome dans les amphibolites et anorthosites a corindon du Vohibory Sud, Madagascar
Translated Title:  Sapphirine and staurolite rich in magnesium and chromium in amphibolites and corundum anorthosites from southern Vohibory, Madagascar.
AU:  Nicollet-C
SO:  Bulletin de Mineralogie. 109; 5, Pages 599-612. 1986. 
PB:  Masson. Paris, France. 1986.
PY:  1986
AN:  1988-031384

Record 260 of 393 in GeoRef Disc 3: 1985-1992

TI:  Polybaric magma mixing in alkalic basalts and kimberlites; evidence from corundum, zircon and ilmenite megacrysts.
AU:  Irving-Anthony-J
BK:  In: Fourth international kimberlite conference.
BA:  Smith-C-B (compiler)
SO:  Abstracts - Geological Society of Australia. 16; Pages 262-264. 1986. 
PB:  Geological Society of Australia. Sydney, N.S.W., Australia. 1986.
PY:  1986
AN:  1988-041423

Record 261 of 393 in GeoRef Disc 3: 1985-1992

TI:  Corganites and corgaspinites; two new types of aluminous assemblages from the Jagersfontein kimberlite pipe.
AU:  Mazzone-Peter; Haggerty-Stephen-E
BK:  In: Fourth international kimberlite conference.
BA:  Smith-C-B (compiler)
SO:  Abstracts - Geological Society of Australia. 16; Pages 279-281. 1986. 
PB:  Geological Society of Australia. Sydney, N.S.W., Australia. 1986.
PY:  1986
AN:  1988-041429

Record 262 of 393 in GeoRef Disc 3: 1985-1992

TI:  Roentgenographische Mengenbestimmung von Steinsalz und Anhydrit
Translated Title:  X-ray quantitative analysis of salt and anhydrite.
AU:  Brokmeier-H-G; Brehler-B
BK:  In: Referate der Vortraege und Poster; 64. Jahrestagung der Deutschen Mineralogischen Gesellschaft
Translated Title:  Abstracts of lectures and poster sessions; 64th Anniversary of the German Mineralogical Society.
BA:  Anonymous
SO:  Fortschritte der Mineralogie, Beiheft. 64; 1, Pages 23. 1986. 
PB:  E. Schweizerbart'sche Verlagsbuchhandlung. Stuttgart, Federal Republic of Germany. 1986.
PY:  1986
AN:  1989-028857

Record 263 of 393 in GeoRef Disc 3: 1985-1992

TI:  Khidrotermalno izmenenie na korigirani do amfibolov systav mergeli s ogled natrievo-alkalnata metasomatoza
Translated Title:  Hydrothermal alteration of marls corrected to hornblende composition in view of sodio-alkaline metasomatism.
AU:  Kanazirski-M-M
SO:  Geokhimiya, Mineralogiya i Petrologiya. 20-21; Pages 145-154. 1986. 
PB:  Bulgarska Akademiya na Naukite. Sofia, Bulgaria. 1986.
PY:  1986
AN:  1989-031726

Record 264 of 393 in GeoRef Disc 3: 1985-1992

TI:  Petrochemistry of gem-bearing basalt in Nong Bon area, Trat Province, eastern Thailand.
AU:  Thanasuthipitak-Theerapongs; Sirinawin-Thanawut
BK:  In: GEOSEA V proceedings; Volume II.
BA:  Teh-G-H (editor); Paramananthan-S (editor)
SO:  Buletin Persatuan Geologi Malaysia = Bulletin Geological Society of Malaysia. 20; Pages 503-521. 1986. 
PB:  Geological Society of Malaysia. Kuala Lumpur, Malaysia. 1986.
PY:  1986
AN:  1991-011174

Record 265 of 393 in GeoRef Disc 3: 1985-1992

TI:  Some geochemical characteristics of alkaline rocks of the Mada Younger Granite complex, Nigeria.
AU:  Abaa-Solomoni-I
BK:  In: Alkaline ring complexes in Africa.
BA:  Black-R (editor); Bowden-Peter (editor)
SO:  Journal of African Earth Sciences. 3; 1-2, Pages 115-120. 1985. 
PB:  Pergamon. London-New York, International. 1985.
PY:  1985
AN:  1986-000956

Record 266 of 393 in GeoRef Disc 3: 1985-1992

TI:  Muscovite breakdown and corundum growth at anomalously low fH (sub 2) O; a study of contact metamorphism and convective fluid movement around the Omey Granite, Connemara, Ireland.
AU:  Ferguson-C-C; Al-Ameen-S-I
SO:  Mineralogical Magazine. 49, Part 4; 353, Pages 505-514. 1985. 
PB:  Mineralogical Society. London, United Kingdom. 1985.
PY:  1985
AN:  1986-008900

Record 267 of 393 in GeoRef Disc 3: 1985-1992

TI:  Charnockites and the genesis of gem minerals.
AU:  Rupasinghe-M-S; Dissanayake-C-B
SO:  Chemical Geology. 53; 1-2, Pages 1-16. 1985. 
PB:  Elsevier. Amsterdam, Netherlands. 1985.
PY:  1985
AN:  1986-026853

Record 268 of 393 in GeoRef Disc 3: 1985-1992

TI:  Layered chondrules; evidence for multistage histories during chondrule formation.
AU:  Prinz-M; Weisberg-M-K; Nehru-C-E; Delaney-Jeremy-S
BK:  In: Abstracts of papers presented at the 48th annual meeting of the Meteoritical Society.
BA:  Moore-Carleton-B (editor)
SO:  Meteoritics. 20; 4, Pages 732-733. 1985. 
PB:  Arizona State University, Center for Meteorite Studies. Tempe, AZ, United States. 1985.
PY:  1985
AN:  1986-050548

Record 269 of 393 in GeoRef Disc 3: 1985-1992

TI:  The generation of corundum-bearing restites in metapelitic rocks.
AU:  Cartwright-I; Barnicoat-A-C
BK:  In: Metamorphic studies; research in progress.
BA:  Brodie-Kate-H (chairperson)
SO:  Journal of the Geological Society of London. 142, Part 6; Pages 1240. 1985. 
PB:  Geological Society of London. London, United Kingdom. 1985.
PY:  1985
AN:  1986-067003

Record 270 of 393 in GeoRef Disc 3: 1985-1992

TI:  (Dis) equilibria involving cordierite-sapphirine-corundum from the "Great Gray-Green, Greasy Limpopo" belt.
AU:  Campion-Moira; Perkins-Dexter
BK:  In: The Geological Society of America; 98th annual meeting.
BA:  Anonymous
SO:  Abstracts with Programs - Geological Society of America. 17; 7, Pages 538. 1985. 
PB:  Geological Society of America (GSA). Boulder, CO, United States. 1985.
PY:  1985
AN:  1986-076336

Record 271 of 393 in GeoRef Disc 3: 1985-1992

TI:  Aluminum speciation in metamorphic fluids.
AU:  Anderson-G-M; Pascal-M-L; Rao-J
BK:  In: GAC, MAC, CGU 1985 joint annual meeting.
BA:  Anonymous
SO:  Program with Abstracts - Geological Association of Canada; Mineralogical Association of Canada; Canadian Geophysical Union, Joint Annual Meeting. 10; Pages A1. 1985. 
PB:  Geological Association of Canada. Waterloo, ON, Canada. 1985.
PY:  1985
AN:  1987-004559

Record 272 of 393 in GeoRef Disc 3: 1985-1992

TI:  Origine des amphibolites a saphirine, corindon et grenat de la formation precambrienne du Vohibory (SW de Madagascar)
Translated Title:  Origin of sapphirine-, corundum- and garnet-bearing amphibolites from the Precambrian Vohibory Formation; Southwest Madagascar.
AU:  Nicollet-C
SO:  Comptes Rendus de l'Academie des Sciences, Serie 2, Mecanique, Physique, Chimie, Sciences de l'Univers, Sciences de la Terre. 301; 3, Pages 167-170. 1985. 
PB:  Gauthier-Villars. Montrouge, France. 1985.
PY:  1985
AN:  1987-043777

Record 273 of 393 in GeoRef Disc 3: 1985-1992

TI:  Corundum-bearing assemblages from the Proterozoic Zn-Pb-Cu deposit of Saxberget, central Sweden.
AU:  Karlsson-K-L
SO:  Geologiska Foereningen i Stockholm Foerhandlingar. 107; 3, Pages 233-239. 1985. 
PB:  Geological Society of Sweden. Stockholm, Sweden. 1985.
PY:  1985
AN:  1987-070375

Record 274 of 393 in GeoRef Disc 3: 1985-1992

TI:  Petrographie und Genese Korund-Spinell-fuehrender Einschluesse in rhyodacitischen Ganggesteinen des mittleren Schluechttals, Suedschwarzwald
Translated Title:  Petrography and genesis of corundum-spinel-bearing inclusions in rhyodacitic dike rocks of the central Schluchttal, southern Black Forest.
AU:  Becker-I
SO:  Oberrheinische Geologische Abhandlungen. 34; 1-2, Pages 1-27. 1985. 
PB:  Verlag C. F. Mueller. Karlsruhe, Federal Republic of Germany. 1985.
PY:  1985
AN:  1990-070258

Record 275 of 393 in GeoRef Disc 2: 1975-1984

TI:  Fluid inclusions in corundum from a contact metamorphic xenolith of the Quaternary Wehr Volcano (East Eifel, Germany).
AU:  Woerner-G; Fricke-A
SO:  Neues Jahrbuch fuer Mineralogie. Monatshefte. 1984; 1, Pages 39-47. 1984. 
PB:  E. Schweizerbart'sche Verlagsbuchhandlung. Stuttgart, Federal Republic of Germany. 1984.
PY:  1984
AN:  1984-045936

Record 276 of 393 in GeoRef Disc 2: 1975-1984

TI:  Petrology of a suite of eclogitic inclusions from the Bobbejaan Kimberlite; I, Two unusual corundum-bearing kyanite eclogites.
AU:  Smyth-J-R; McCormick-T-C; Caporuscio-F-A
BK:  In: Kimberlites; II, The mantle and crust-mantle relationships.
BA:  Kornprobst-J (editor)
CT:  In the collection: Developments in petrology. 1984.
SO:  11B; Pages 109-119. 1984. 
PB:  Elsevier Sci. Publ.. Amsterdam, Netherlands. 1984.
PY:  1984
AN:  1984-046722

Record 277 of 393 in GeoRef Disc 2: 1975-1984

TI:  Petrology of a suite of eclogite inclusions from the Bobbejaan Kimberlite; II, Primary phase compositions and origin.
AU:  Smyth-J-R; Caporuscio-F-A
BK:  In: Kimberlites; II, The mantle and crust-mantle relationships.
BA:  Kornprobst-J (editor)
CT:  In the collection: Developments in petrology. 1984.
SO:  11B; Pages 121-131. 1984. 
PB:  Elsevier Sci. Publ.. Amsterdam, Netherlands. 1984.
PY:  1984
AN:  1984-046723

Record 278 of 393 in GeoRef Disc 2: 1975-1984

TI:  A thermodynamic model for subsolidus equilibria in the system CaO-MgO-Al (sub 2) O (sub 3) -SiO (sub 2) .
AU:  Wood-Bernard-J; Holloway-John-R
SO:  Geochimica et Cosmochimica Acta. 48; 1, Pages 159-176. 1984. 
PB:  Pergamon. Oxford, International. 1984.
PY:  1984
AB:  The study integrates phase equilibrium and calorimetric data for the following phases in the CaO-MgO-Al (sub 2) O (sub 3) -SiO (sub 2) system: clinopyroxene, orthopyroxene, garnet, forsterite, anorthite, spinel, kyanite, sillimanite, corundum and quartz. The internally consistent data set includes mixing properties for clinopyroxene, orthopyroxene, and garnet solid solutions and enables calculation of any equilibrium involving the components of the above 10 phases under any desired P, T conditions. Major conclusions of the study are: (1) Spinel appears to have an enthalpy of Mg-Al exchange on the order of 20 Kcal or more, substantially above the calorimetrically measured value. (2) CaAl (sub 2) SiO (sub 6) pyroxene has virtually complete Al-Si disorder. (3) Enstatite has an enthalpy of formation from oxides at 1000 K of about-16840 cal/mole, substantially greater than the calorimetric value of -17620+ or -340 cal. (4) Anorthite has about 0.6 cal/K entropy of Al-Si disorder. (5) CMAS garnets of between Pyrope (sub 100) and Pyrope (sub 80) Grossular (sub 20) composition have almost zero excess entropy. (6) Nonstoichiometry in clinopyroxene has a moderate but predictable influence on reaction boundaries in SiO (sub 2) -saturated compositions.
AN:  1984-052114

Record 279 of 393 in GeoRef Disc 2: 1975-1984

TI:  High-magnesium staurolite in a sapphirine-garnet rock from the Limpopo Belt, Southern Africa.
AU:  Schreyer-W; Horrocks-Peter-C; Abraham-K
SO:  Contributions to Mineralogy and Petrology. 86; 2, Pages 200-207. 1984. 
PB:  Springer International. Heidelberg-New York, International. 1984.
PY:  1984
AB:  Unusually Mg-rich staurolite with F = Fe/(Fe+Mg) = 0.51 occurs in a peraluminous silica-deficient sapphirine-garnet-gedrite-spinel-corundum-phlogopite rock as relic inclusions within pyrope-almandine garnet (F = 0.43-0.48), from which it is generally separated by sapphirine (F = 0.19). Gedrite has F = 0.24-0.27, phlogopite 0.19, and spinel 0.43. The gradual disappearance of staurolite is due to a shift of the 3-phase AFM assemblage staurolite-garnet-sapphirine to more Fe-rich compositions according to probably prograde reactions between staurolite and garnet to form sapphirine together with either quartz or gedrite. Thus still more Mg-rich staurolite seems to have existed in the rock at earlier stages of metamorphism characterized by lower temperatures and perhaps higher pressures. The local equilibria now frozen in indicate minimum pressures of 7-8 kbar and temperatures in excess of about 800 degrees C. Staurolite is free from Zn, very low in Si, and richer in Ti than any other staurolite found thus far. Most notable is the Mg/Fe fraction between staurolite and garnet with staurolite being the more Fe-rich phase (K (sub D) = 1.32).--Modified journal abstract.
AN:  1984-052853

Record 280 of 393 in GeoRef Disc 2: 1975-1984

TI:  Mineral parageneses and metamorphic reactions in metasedimentary enclaves from the Archaean Gneiss Complex of North-west India.
AU:  Sharma-R-S; Windley-Brian-F
SO:  Mineralogical Magazine. 48, Part 2; 347, Pages 195-209. 1984. 
PB:  Mineralogical Society. London, United Kingdom. 1984.
PY:  1984
AB:  Three metasedimentary enclaves. Banded Gneissic Complex (>2580Ma). The kyanite-chloritoid-muscovite schist with quartz or corundum, and kyanite-fuchsite-corundum+ or -diaspore was metamorphosed under lower amphibolite conditions, and is thus not isofacial with the surrounding schists and gneisses (of the "basement" complex) which reached sillimanite-grade metamorphism in the last orogenic cycle (Aravalli: 1650-950Ma Orogeny) in Rajasthan. A calc-silicate rock occurs as a small lens. The presence of two generations of wollastonite which formed during different metamorphic events in the calcite-quartz-grossularite-anorthite-clinopyroxene assemblage indicates polymetamorphism. A metabasic rock records a complete polymetamorphic history in discontinuous zones in garnet coexisting with hornblende-chlorite-plagioclase-quartz+ or -epidote. The mineralogy of the calc-silicate and metabasic enclaves gives a recrystallization temperature of c. 700 degrees C and a pressure in the range of 8-3 kbar during the second metamorphism.--Modified journal abstract.
AN:  1985-003858

Record 281 of 393 in GeoRef Disc 2: 1975-1984

TI:  Petrology of garnet-, spinel-, and sillimanite-bearing granites from the Bavarian Forest, West Germany.
AU:  Propach-G; Gillessen-Barbara
SO:  TMPM. Tschermaks Mineralogische und Petrographische Mitteilungen. 33; 1, Pages 67-75. 1984. 
PB:  Springer-Verlag. Vienna, Austria. 1984.
PY:  1984
AB:  17 small granitic intrusions of late-Variscan age. All of them contain biotite, 14 cordierite, 6 andalusite, 2 garnet, green spinel, and rare sillimanite. The granites are peraluminous (normative corundum between 1.0 and 3.5 per cent) and highly evolved. Biotite and garnet in the garnet-bearing granites are highly ferrous, MnO in garnet is moderate (3 to 5 per cent), the spinel is essentially hercynite with 2 to 16 per cent ZnO. From textural relationships the sequence of crystallization of the aluminous minerals is deduced as: cordierite 1 + biotite 1, reaction of biotite 1 and some cordierite 1 to garnet (+ sillimanite?), rimming of garnet by cordierite 2 and biotite 2, growth of spinel in plagioclase, in cordierite 1, and around sillimanite. The pressure during the magmatic stage was between 2 and 3 kb.--Modified journal abstract.
AN:  1985-008696

Record 282 of 393 in GeoRef Disc 2: 1975-1984

TI:  S-type characteristics of the Hercynian granitoids of the Central Palaeozoic Massif, Morocco.
AU:  Mahmood-A; Bennani-A
SO:  Geological Magazine. 121; 4, Pages 301-311. 1984. 
PB:  Cambridge University Press. London, United Kingdom. 1984.
PY:  1984
AB:  This study of the Hercynian granitoids of the Central Palaeozoic Massif of Morocco covers the Zaer, Ment, Oulmes, and Moulay Bouazza plutons. These plutons are formed of biotite or two-mica, quartz-rich granodiorites and monzogranites containing reddish-brown, inclusion-rich biotites as the only essential mafic mineral; zoned plagioclase; and perthitic K-feldspar. The modal contents of micas and K-feldspar are highly variable. Medium to coarse grained, massive; however foliated varieties are also commonly found, particularly at the contact of the plutons with sedimentary rocks. The strongly peraluminous character of the granitoids is shown by high normative corundum and high molar Al (sub 2) O (sub 3) /(CaO+Na (sub 2) O+K (sub 2) O) ratio, and is reflected by the occasional presence of aluminosilicates. The mineralogical and chemical characteristics of the granitoids are similar to those of the S-type granites, and were inherited from the crustal source of the granitic magmas which are thought to have been generated by partial equilibrium fusion of the sandy argillaceous sediments of the Massif. The heat source for the fusion might have been provided by intrusion of mantle-derived material. --Modified journal abstract.
AN:  1985-008822

Record 283 of 393 in GeoRef Disc 2: 1975-1984

TI:  Thermodynamic mixing properties of Mg(Al, Cr) (sub 2) O (sub 4) spinel crystalline solution at high temperatures and pressures.
AU:  Oka-Yastami; Steinke-Petra; Chatterjee-Niranjan-D
SO:  Contributions to Mineralogy and Petrology. 87; 2, Pages 196-204. 1984. 
PB:  Springer International. Heidelberg-New York, International. 1984.
PY:  1984
AB:  Three Al--Cr exchange isotherms at 1,250 degrees , 1,050 degrees , and 796 degrees between Mg(Al, Cr) (sub 2) O (sub 4) spinel and (Al, Cr) (sub 2) O (sub 3) corundum crystalline solutions have been studied experimentally at 25 kbar pressure. Using the equation of state of (Al, Cr) (sub 2) O (sub 3) crystalline solution and assuming that the Mg(Al, Cr) (sub 2) O (sub 4) can be treated in terms of the asymmetric Margules relation, the exchange isotherms were solved for Delta G (super *) , W (super Sp) G, MgAl (sub 2) O (sub 4) and W (super Sp) G, MgCr (sub 2) O (sub 4) . The best constrained data set from the 1,250 degrees C isotherm shows that the latter two quantities do not overlap within three standard deviations. Temperature-dependence of G (super ex) (sub m) is best constrained in the range 796-1,250 degrees C. Extrapolation to lower temperature shows tentatively that at 1 bar pressure the critical temperature, T (sub c) , of the spinel solvus is 427 degrees C, with dT (sub c) /dP nearly equal 1.3 K/kbar. The critical composition, X (sub c) , is 0.42 X (super Sp) MgCr (sub 2) O (sub 4) , and changes barely with pressure.
AN:  1985-020756

Record 284 of 393 in GeoRef Disc 2: 1975-1984

TI:  Korund und Margarit fuehrende Blackwall-Gesteine in Serpentinit-Hornfelsen
Translated Title:  Corundum- and margarite-bearing Blackwall rocks in serpentinite-hornfels.
AU:  Olesch-M; Matthes-S
BK:  In: Referate der Vortraeage und Poster auf der 62. Jahrestagung der Deutschen Mineralogischen Gesellschaft, gemeinsam mit der Oesterreichischen Mineralogischen Gesellschaft und der Schweizerischen Mineralogischen und Petrographischen Gesellschaft
Translated Title:  Abstracts of presentations and posters from the Sixty-second annual meeting of the German Mineralogical Society in cooperation with the Austrian Mineralogical Society and the Swiss Mineralogic and Petrographic Society.
BA:  Anonymous
SO:  Fortschritte der Mineralogie, Beiheft. 62; 1, Pages 179-181. 1984. 
PB:  E. Schweizerbart'sche Verlagsbuchhandlung. Stuttgart, Federal Republic of Germany. 1984.
PY:  1984
AN:  1985-026546

Record 285 of 393 in GeoRef Disc 2: 1975-1984

TI:  Corundum - sapphirine - spinel amphibolites containing relict Zn - Al chromite; possible metamorphosed mafic igneous rocks, Kittilae, Finnish Lapland.
AU:  Schumacher-J-C
BK:  In: Referate der Vortraeage und Poster auf der 62. Jahrestagung der Deutschen Mineralogischen Gesellschaft, gemeinsam mit der Oesterreichischen Mineralogischen Gesellschaft und der Schweizerischen Mineralogischen und Petrographischen Gesellschaft
Translated Title:  Abstracts of presentations and posters from the Sixty-second annual meeting of the German Mineralogical Society in cooperation with the Austrian Mineralogical Society and the Swiss Mineralogic and Petrographic Society.
BA:  Anonymous
SO:  Fortschritte der Mineralogie, Beiheft. 62; 1, Pages 228-229. 1984. 
PB:  E. Schweizerbart'sche Verlagsbuchhandlung. Stuttgart, Federal Republic of Germany. 1984.
PY:  1984
AN:  1985-026585

Record 286 of 393 in GeoRef Disc 2: 1975-1984

TI:  A staurolite-talc assemblage in tourmaline-phlogopite-chlorite schist from northern Victoria Land, Antarctica, and its petrogenetic significance.
AU:  Grew-E-S; Sandiford-Michael
SO:  Contributions to Mineralogy and Petrology. 87; 4, Pages 337-350. 1984. 
PB:  Springer International. Heidelberg-New York, International. 1984.
PY:  1984
AN:  1985-033158

Record 287 of 393 in GeoRef Disc 2: 1975-1984

TI:  The system CaO-Al (sub 2) O (sub 3) -SiO (sub 2) -H (sub 2) O; new phase equilibria data, some calculated phase relations, and their petrological applications.
AU:  Chatterjee-N-D; Johannes-W; Leistner-H
SO:  Contributions to Mineralogy and Petrology. 88; 1-2, Pages 1-13. 1984. 
PB:  Springer International. Heidelberg-New York, International. 1984.
PY:  1984
AN:  1985-038022

Record 288 of 393 in GeoRef Disc 2: 1975-1984

TI:  Petrographic studies of refractory inclusions from the Murchison Meteorite.
AU:  MacPherson-Glenn-J; Grossman-Lawrence; Hashimoto-Akihiko; Bar-Matthews-Miryam; Tanaka-Tsuyoshi
BK:  In: Proceedings of the Fifteenth lunar and planetary science conference, Part 1.
BA:  Ryder-Graham (editor); Schubert-Gerald (editor)
SO:  JGR. Journal of Geophysical Research. B. 89, Suppl. 1; Pages C299-C312. 1984. 
PB:  American Geophysical Union. Washington, DC, United States. 1984.
PY:  1984
AN:  1985-038333

Record 289 of 393 in GeoRef Disc 2: 1975-1984

TI:  Sapphirine-bearing assemblages from Kiranur, southern India; a study of chemographic relationships in the Na (sub 2) O-FeO-MgO-Al (sub 2) O (sub 3) -SiO (sub 2) -H (sub 2) O system.
AU:  Lal-R-K; Ackermand-D; Raith-M; Raase-P; Seifert-F
SO:  Neues Jahrbuch fuer Mineralogie. Abhandlungen. 150; 2, Pages 121-152. 1984. 
PB:  E. Schweizerbart'sche Verlagsbuchhandlung. Stuttgart, Federal Republic of Germany. 1984.
PY:  1984
AN:  1985-052894

Record 290 of 393 in GeoRef Disc 2: 1975-1984

TI:  New associations of native elements in ultrabasites.
AU:  Rudashevskii-N-S-(Rudashevskiy-Nikolay-Semenovich); Mochalov-A-G
SO:  Soviet Geology and Geophysics. 25; 4, Pages 35-41. 1984. 
PB:  Allerton Press. New York, NY, United States. 1984.
PY:  1984
AN:  1985-053105

Record 291 of 393 in GeoRef Disc 2: 1975-1984

BK:  Experimental and theoretical investigation of quartz and corundum solubilities and their application to phase equilibria and mass transfer in the geothermal system, Svartsengi, Iceland.
BA:  Ragnarsdottir-Kristin-Vala
PY:  1984
DG:  Doctoral
DI:  Michigan State University. East Lansing, MI, United States. Pages: 128. 1984.
AN:  1985-068870

Record 292 of 393 in GeoRef Disc 2: 1975-1984

TI:  Trace elements in high-temperature inclusions from Murchison.
AU:  Ekambaram-Vanavan; Sluk-S-M; Grossman-L; Davis-Andrew-M
BK:  In: Abstracts of papers presented at the 47th annual meeting; the Meteoritical Society.
BA:  Anonymous
SO:  Meteoritics. 19; 4, Pages 222-223. 1984. 
PB:  Arizona State University, Center for Meteorite Studies. Tempe, AZ, United States. 1984.
PY:  1984
AN:  1985-070215

Record 293 of 393 in GeoRef Disc 2: 1975-1984

TI:  Magnesium and calcium isotopes in hibonite-bearing CAIs.
AU:  Hinton-R-W; Grossman-L; MacPherson-Glenn-J
BK:  In: Abstracts of papers presented at the 47th annual meeting; the Meteoritical Society.
BA:  Anonymous
SO:  Meteoritics. 19; 4, Pages 240-241. 1984. 
PB:  Arizona State University, Center for Meteorite Studies. Tempe, AZ, United States. 1984.
PY:  1984
AN:  1985-070235

Record 294 of 393 in GeoRef Disc 2: 1975-1984

TI:  Experimentally determined stability of clinopyroxene + garnet + corundum in the system CaO-MgO-Al (sub 2) O (sub 3) -SiO (sub 2) .
AU:  Gasparik-Tibor
SO:  American Mineralogist. 69; 11-12, Pages 1025-1035. 1984. 
PB:  Mineralogical Society of America. Washington, DC, United States. 1984.
PY:  1984
AN:  1986-019181

Record 295 of 393 in GeoRef Disc 2: 1975-1984

TI:  Ferric iron in sapphirine; a Moessbauer spectroscopic study.
AU:  Steffen-G; Seifert-F; Amthauer-G
SO:  American Mineralogist. 69; 3-4, Pages 339-348. 1984. 
PB:  Mineralogical Society of America. Washington, DC, United States. 1984.
PY:  1984
AN:  1986-019489

Record 296 of 393 in GeoRef Disc 2: 1975-1984

TI:  Metamorphism, deformation, tectonic significance of the Cheyenne Belt, Medicine Bow Mountains, Wyoming.
AU:  Duebendorfer-Ernest-M
BK:  In: The Geological Society of America, 97th annual meeting.
SO:  Abstracts with Programs - Geological Society of America. 16; 6, Pages 495. 1984. 
PB:  Geological Society of America (GSA). Boulder, CO, United States. 1984.
PY:  1984
AN:  1986-040983

Record 297 of 393 in GeoRef Disc 2: 1975-1984

TI:  Disequilibrium features in contact metamorphosed Emery, Cortlandt Complex, New York.
AU:  Tracy-Robert-J; McLellan-Eileen-L; Waldron-Kim-A
BK:  In: The Geological Society of America, Northeastern Section, 19th annual meeting.
SO:  Abstracts with Programs - Geological Society of America. 16; 1, Pages 68. 1984. 
PB:  Geological Society of America (GSA). Boulder, CO, United States. 1984.
PY:  1984
AN:  1987-010051

Record 298 of 393 in GeoRef Disc 2: 1975-1984

TI:  Decouverte d'enclaves hyper-alumineuses dans l'ortho-gneiss de l'ile d'Yeu
Translated Title:  Discovery of hyperaluminous inclusions in the orthogneiss of Yeu Island, Vendee, France.
AU:  Semelin-B; Marchand-J
SO:  Comptes-Rendus des Seances de l'Academie des Sciences, Serie 2: Mecanique-Physique, Chimie, Sciences de l'Univers, Sciences de la Terre. 299; 10, Pages 633-638. 1984. 
PB:  Gauthier-Villars. Montrouge, France. 1984.
PY:  1984
AN:  1987-018476

Record 299 of 393 in GeoRef Disc 2: 1975-1984

TI:  Osobennosti flyuidnogo rezhima formirovaniya korund-normativnykh magmaticheskikh porod
Translated Title:  Particularities of the fluid regime during the genesis of magmatic rocks rich in corundum.
AU:  Martynov-Yu-A
SO:  Doklady Akademii Nauk SSSR. 278; 4, Pages 971-974. 1984. 
PB:  Akademiya Nauk SSSR. Moscow, USSR. 1984.
PY:  1984
AN:  1987-025624

Record 300 of 393 in GeoRef Disc 2: 1975-1984

TI:  Effect of H (sub 2) O on liquidus relationships in MgO-Al (sub 2) O (sub 3) -SiO (sub 2) at 30 kilobars.
AU:  Sekine-Toshimori; Wyllie-Peter-J
SO:  Journal of Geology. 91; 2, Pages 195-210. 1983. 
PB:  University of Chicago Press. Chicago, IL, United States. 1983.
PY:  1983
AN:  1983-041081

Record 301 of 393 in GeoRef Disc 2: 1975-1984

TI:  Aktsesorni minerali magnezial'nikh ul'traosnovnikh porid dokembriyu Verkhivtsevs'koyi sinklinali
Translated Title:  Accessory minerals in the Precambrian magnesium-rich ultramafics from the Verkhovtsevo Syncline.
AU:  Stul-chikov-V-O; Ilovays-ka-S-V
SO:  Dopovidi Akademiyi Nauk Ukrayins'koyi RSR, Seriya B: Geologichni, Khimichni ta Biologichni Nauki. 1983; 3, Pages 31-33. 1983. 
PB:  Izdavnitstvo Naukova Dumka. Kiev, USSR. 1983.
PY:  1983
AN:  1983-041254

Record 302 of 393 in GeoRef Disc 2: 1975-1984

TI:  Alkremite, garnetite and eclogite xenoliths from Bellsbank and Jagersfontein, South Africa.
AU:  Exley-Richard-A; Smith-Joseph-V; Dawson-J-Barry
SO:  American Mineralogist. 68; 5-6, Pages 512-516. 1983. 
PB:  Mineralogical Society of America. Washington, DC, United States. 1983.
PY:  1983
AB:  Textural and mineralogical evidence of crystal fractionation from evolving aluminous magma; Ca and P increase in garnet as Cr and Ti decrease in most spinels. Several parental magmas. Corundum in alkremites contains 0.1-0.2 wt.% TiO (sub 2) , 0.2-0.5 Cr (sub 2) O (sub 3) , and 0.5-1.2 Fe (sub 2) O (sub 3) . Mica (0.7-3.4 TiO (sub 2) ) in grain boundaries is secondary. Foundering or subduction of Al-rich sediments (perhaps chloritized ocean crust) may have generated local Al enrichment in the upper mantle to provide diverse source regions for alkremite magmas.--Modified journal abstract.
AN:  1983-060097

Record 303 of 393 in GeoRef Disc 2: 1975-1984

TI:  Possible genetic relationship between the rockford-type granites and the Bluff Springs granite.
AU:  Allison-David-T
BK:  In: 32nd annual meeting, Southeastern Section, Geological Society of America; with the Southeast Section of the National Association of Geology Teachers and the Southeastern Section of the Paleontological Society.
BA:  Anonymous
SO:  Abstracts with Programs - Geological Society of America. 15; 2, Pages 46. 1983. 
PB:  Geological Society of America (GSA). Boulder, CO, United States. 1983.
PY:  1983
AN:  1983-061941

Record 304 of 393 in GeoRef Disc 2: 1975-1984

TI:  Rockford Granite; an S-type felsic plutonic suite in the northern Alabama Piedmont.
AU:  Drummond-Mark-S; Ragland-Paul-C
BK:  In: 32nd annual meeting, Southeastern Section, Geological Society of America; with the Southeast Section of the National Association of Geology Teachers and the Southeastern Section of the Paleontological Society.
BA:  Anonymous
SO:  Abstracts with Programs - Geological Society of America. 15; 2, Pages 46. 1983. 
PB:  Geological Society of America (GSA). Boulder, CO, United States. 1983.
PY:  1983
AN:  1983-061942

Record 305 of 393 in GeoRef Disc 2: 1975-1984

TI:  Feldspar solubility and the transport of aluminum under metamorphic conditions.
AU:  Anderson-G-M; Burnham-Charles-Wayne
BK:  In: Orville volume; Studies in metamorphism and metasomatism.
BA:  Greenwood-Hugh-J (editor)
SO:  American Journal of Science. 283-A; Pages 283-297. 1983. 
PB:  Kline Geology Laboratory, Yale University. New Haven, CT, United States. 1983.
PY:  1983
AN:  1984-001218

Record 306 of 393 in GeoRef Disc 2: 1975-1984

TI:  Phase equilibria in the system containing muscovite, paragonite, alkaline feldspars, H (sub 2) O, and CO (sub 2) .
AU:  Shvedenkov-G-Yu; Shvedenkova-S-V; Dashevskii-Yu-A-(Dashevskiy-Yu-A); Kalinin-D-V
SO:  Soviet Geology and Geophysics. 24; 1, Pages 73-79. 1983. 
PB:  Allerton Press. New York, NY, United States. 1983.
PY:  1983
AN:  1984-012388

Record 307 of 393 in GeoRef Disc 2: 1975-1984

TI:  Pyroxene-garnet-corundum equilibria in the system CaO-MgO-Al (sub 2) O (sub 3) -SiO (sub 2) .
AU:  Gasparik-T
BK:  In: American Geophysical Union; 1983 spring meeting.
BA:  Anonymous
SO:  Eos, Transactions, American Geophysical Union. 64; 18, Pages 347. 1983. 
PB:  American Geophysical Union. Washington, DC, United States. 1983.
PY:  1983
AN:  1985-028888

Record 308 of 393 in GeoRef Disc 2: 1975-1984

TI:  Aluminous enclaves in orthoamphibole gneiss, Finland.
AU:  Tracy-Robert-J; Merewether-Paul-A
BK:  In: American Geophysical Union; 1983 spring meeting.
BA:  Anonymous
SO:  Eos, Transactions, American Geophysical Union. 64; 18, Pages 351. 1983. 
PB:  American Geophysical Union. Washington, DC, United States. 1983.
PY:  1983
AN:  1985-028918

Record 309 of 393 in GeoRef Disc 2: 1975-1984

TI:  A corundum and sapphirine paragenesis from the Limpopo mobile belt, Southern Africa.
AU:  Horrocks-P-C
SO:  Journal of Metamorphic Geology. 1; 1, Pages 13-23. 1983. 
PB:  Blackwell. Oxford, United Kingdom. 1983.
PY:  1983
AN:  1985-068984

Record 310 of 393 in GeoRef Disc 2: 1975-1984

TI:  New discovery of a gneiss with corundum in Ryoke metamorphic belt, central Japan.
AU:  Tezuka-T
SO:  Chishitsugaku Zasshi = Journal of the Geological Society of Japan. 89; 4, Pages 243-244. 1983. 
PB:  Nippon Chishitsugaku Gakkai. Tokyo, Japan. 1983.
PY:  1983
AN:  1986-013283

Record 311 of 393 in GeoRef Disc 2: 1975-1984

TI:  Existence de granulites de haute pression a clinopyroxene-grenat dans les formations precambriennes du Vohibory (SW de Madagascar)
Translated Title:  Occurrence of high pressure granulites in the Precambrian Vohibory area; Southwest Malagasy Republic.
AU:  Nicollet-C
SO:  Comptes-Rendus des Seances de l'Academie des Sciences, Serie 2: Mecanique-Physique, Chimie, Sciences de l'Univers, Sciences de la Terre. 297; 2, Pages 145-148. 1983. 
PB:  Gauthier-Villars. Montrouge, France. 1983.
PY:  1983
AN:  1986-026287

Record 312 of 393 in GeoRef Disc 2: 1975-1984

TI:  Note on the graphite-free corundum-K feldspar gneiss in the Hida metamorphic belt, central Japan.
AU:  Osakabe-T; Suzuki-M
SO:  Journal of Science of the Hiroshima University, Series C: Geology and Mineralogy. 8; 1, Pages 31-42. 1983. 
PB:  Hiroshima Daigaku. Hiroshima, Japan. 1983.
PY:  1983
AN:  1986-031700

Record 313 of 393 in GeoRef Disc 2: 1975-1984

TI:  Gneissic xenolith with corundum-cordierite of the Anko-minamisawa mafic mass, Ryoke metamorphic belt, central Japan.
AU:  Tezuka-T
SO:  Chishitsugaku Zasshi = Journal of the Geological Society of Japan. 89; 7, Pages 403-406. 1983. 
PB:  Nippon Chishitsugaku Gakkai. Tokyo, Japan. 1983.
PY:  1983
AN:  1986-048498

Record 314 of 393 in GeoRef Disc 2: 1975-1984

TI:  Thermodynamic mixing properties of corundum-eskolaite, alpha -(Al, Cr (super +3) ) (sub 2) O (sub 3) , crystalline solutions at high temperatures and pressures.
AU:  Chatterjee-Niranjan-D; Leistner-Hans; Terhart-Ludger; Abraham-Kurt; Klaska-Rolf
SO:  American Mineralogist. 67; 7-8, Pages 725-735. 1982. 
PB:  Mineralogical Society of America. Washington, DC, United States. 1982.
PY:  1982
AN:  1983-005693

Record 315 of 393 in GeoRef Disc 2: 1975-1984

TI:  Corundum-bearing schist from the Willyama Complex Thackaringa, N.S.W.
AU:  Plimer-I-R
SO:  Australian Gem and Treasure Hunter. 72; Pages 215-216. 1982. 
PB:  Minelab Electronic Industries Limited. Stepney, South Aust., Australia. 1982.
PY:  1982
AN:  1983-017247

Record 316 of 393 in GeoRef Disc 2: 1975-1984

TI:  Corundum- and kyanite-bearing anatexites from the Precambrian of Tanzania.
AU:  Altherr-R; Okrusch-M; Bank-H
SO:  Lithos. 15; 3, Pages 191-197. 1982. 
PB:  Elsevier. Amsterdam, International. 1982.
PY:  1982
AN:  1983-026612

Record 317 of 393 in GeoRef Disc 2: 1975-1984

TI:  A corundum-rich inclusion in the Murchison carbonaceous chondrite.
AU:  Bar-Matthews-M; Hutcheon-I-D; MacPherson-G-J; Grossman-L
SO:  Geochimica et Cosmochimica Acta. 46; 1, Pages 31-41. 1982. 
PB:  Pergamon. Oxford, International. 1982.
PY:  1982
AN:  1983-026622

Record 318 of 393 in GeoRef Disc 2: 1975-1984

TI:  Petrology of the alkaline rocks around Sivamalai, Coimbatore District, Tamilnadu, India.
AU:  Rao-B-Bhaskar
SO:  Geologische Rundschau. 71; 1, Pages 263-279. 1982. 
PB:  Springer International. Berlin, Federal Republic of Germany. 1982.
PY:  1982
AN:  1984-018261

Record 319 of 393 in GeoRef Disc 2: 1975-1984

TI:  Fuchsite-aluminium silicate rocks in Archaean greenstone belts; are they metamorphosed alunite deposits?.
AU:  Schreyer-W
SO:  Geologische Rundschau. 71; 1, Pages 347-368. 1982. 
PB:  Springer International. Berlin, Federal Republic of Germany. 1982.
PY:  1982
AN:  1984-018266

Record 320 of 393 in GeoRef Disc 2: 1975-1984

TI:  Ruby from the Sanbagawa metamorphic belt, in the Hodono Valley, Ehime Prefecture, Japan.
AU:  Minakawa-T; Momoi-H
SO:  Mineralogical Journal. 11; 2, Pages 78-83. 1982. 
PB:  Nippon Kobutsu Gakkai; Japan Publications Trading Co., Ltd.. Tokyo, Japan. 1982.
PY:  1982
AN:  1984-043857

Record 321 of 393 in GeoRef Disc 2: 1975-1984

TI:  Studies on corundum bearing pegmatite and contact rock near Kalyadi, Hassan District, Karnataka.
AU:  Bhaskar-Rao-P; Reddy-T-R-K; Venkataraman-G
SO:  Indian Journal of Earth Sciences. 9; 2, Pages 201-205. 1982. 
PB:  Indian Society of Earth Sciences. Calcutta, India. 1982.
PY:  1982
AN:  1985-043931

Record 322 of 393 in GeoRef Disc 2: 1975-1984

TI:  Mineral resource potential of mafic and ultramafic rocks of the Southern Appalachians.
AU:  Lipin-Bruce-R; Gottfried-David; McSween-Harry-Y Jr.
BK:  In: The Geological Society of America, 95th annual meeting.
SO:  Abstracts with Programs - Geological Society of America. 14; 7, Pages 547. 1982. 
PB:  Geological Society of America (GSA). Boulder, CO, United States. 1982.
PY:  1982
AN:  1986-015837

Record 323 of 393 in GeoRef Disc 2: 1975-1984

TI:  Petrology of a suite of eclogite inclusions from the Bobbejaan Mine, South Africa; Part II, Two unique corundum grospydites.
AU:  Smyth-J-R; Caporuscio-F-A
BK:  In: Third international kimberlite conference; abstracts.
BA:  Anonymous
SO:  Terra Cognita. 2; 3, Pages 219-220. 1982. 
PB:  European Union of Geosciences. Strasbourg, France. 1982.
PY:  1982
AN:  1986-024440

Record 324 of 393 in GeoRef Disc 2: 1975-1984

TI:  Petrology and geochemistry of mantle eclogite xenoliths from Colorado-Wyoming kimberlites.
AU:  Ater-P-C; McCallum-M-E; Eggler-D-H
BK:  In: Third international kimberlite conference; abstracts.
BA:  Anonymous
SO:  Terra Cognita. 2; 3, Pages 221-222. 1982. 
PB:  European Union of Geosciences. Strasbourg, France. 1982.
PY:  1982
AN:  1986-024447

Record 325 of 393 in GeoRef Disc 2: 1975-1984

TI:  Single-crystal structure refinements of super-silicic clinopyroxenes from the Zagadochnaya kimberlite pipe, Yakutia, USSR.
AU:  Smith-D-C; Domeneghetti-Chiara; Rossi-Giuseppe; Ungaretti-Luciano
BK:  In: Third international kimberlite conference; abstracts.
BA:  Anonymous
SO:  Terra Cognita. 2; 3, Pages 223. 1982. 
PB:  European Union of Geosciences. Strasbourg, France. 1982.
PY:  1982
AN:  1986-024451

Record 326 of 393 in GeoRef Disc 2: 1975-1984

TI:  Thermodynamic properties of minerals in the system CaO-MgO-Al (sub 2) O (sub 3) -SiO (sub 2) .
AU:  Wood-Bernard-J; Holloway-John-R
BK:  In: The Geological Society of America, 95th annual meeting.
SO:  Abstracts with Programs - Geological Society of America. 14; 7, Pages 649. 1982. 
PB:  Geological Society of America (GSA). Boulder, CO, United States. 1982.
PY:  1982
AN:  1986-057078

Record 327 of 393 in GeoRef Disc 2: 1975-1984

TI:  Nigerite-hogbomite-spinel assemblages from Manitouwadge, Ontario and their significance.
AU:  Essene-Eric-J; Petersen-Erich-U; Peacor-D-R
BK:  In: AGU 1982 spring meeting; abstracts.
SO:  Eos, Transactions, American Geophysical Union. 63; 18, Pages 456. 1982. 
PB:  American Geophysical Union. Washington, DC, United States. 1982.
PY:  1982
AN:  1986-062192

Record 328 of 393 in GeoRef Disc 2: 1975-1984

TI:  A rare occurrence of corundum-corona from the migmatite terrain of Kerala; a case of desilication.
AU:  Vidyadharan-K-T
SO:  Records of the Geological Survey of India. 114; 5, Pages 54-59. 1982. 
PB:  Geological Survey of India. Calcutta, India. 1982.
PY:  1982
AN:  1987-005915

Record 329 of 393 in GeoRef Disc 2: 1975-1984

TI:  Tsel'zianova mineralizatsiya v porodakh Pliskivs'koyi strukturi
Translated Title:  Celsian mineralization in rocks of the Pliskovian Structure.
AU:  Shramenko-I-F; Stadnik-V-O; Kostyuchenko-V-S
SO:  Dopovidi Akademiyi Nauk Ukrayins'koyi RSR, Seriya B: Geologichni, Khimichni ta Biologichni Nauki. 4, Pages 22-25. 1981. 
PB:  Izdavnitstvo Naukova Dumka. Kiev, USSR. 1981.
PY:  1981
AN:  1981-048253

Record 330 of 393 in GeoRef Disc 2: 1975-1984

TI:  Desilicified pegmatites with dravite and corundum (southwestern Pamir).
AU:  Rossovskiy-L-N; Konovalenko-S-I; Bovin-Yu-P
SO:  International Geology Review. 23; 4, Pages 371-382. 1981. 
PB:  Winston & Son. Silver Spring, MD, United States. 1981.
PY:  1981
AB:  We studied the corundum plagioclasites which occur with dravite in the Archean crystalline sequences of the Shakhdara Range (southwestern Pamir). The corundum plagioclasites form small veins (0.5-20x2-140 m) in magnetite calciphyres and forsterites. The principal rock-forming mineral is a plagioclase of variable composition (An (sub 15-100) ). The typomorphic minerals are corundum and dravite. At the contact between the plagioclasites and the country rocks, there are always one or several bi- and monomineralic selvages: amphibole, corundum-amphibole, and phlogopite. The corundum plagioclasite s formed at the expense of normal quartz-microcline-plagioclase pegmatites, granite pegmatites, and aplites during a high-temperature infiltration-diffusion bimetasomatism. The superimposed solutions, which caused the metasomatism, were produced by metamorphism of the surrounding sequences under conditions of the amphibolite facies. We suggest that the corundum plagioclasites of the southwestern Pamir are prospective for supplies of precious varieties of corundum.
AN:  1981-051467

Record 331 of 393 in GeoRef Disc 2: 1975-1984

TI:  Interactions between the iron and the aluminium minerals during the heating of Venezuelan lateritic bauxites; II, X-ray diffraction study.
AU:  Yariv-S; Mendelovici-E; Villalba-R
SO:  Thermochimica Acta. 45; 3, Pages 339-348. 1981. 
PB:  Elsevier. Amsterdam, Netherlands. 1981.
PY:  1981
AN:  1982-049525

Record 332 of 393 in GeoRef Disc 2: 1975-1984

TI:  The application of spinel-bearing metapelites P/ T determinations; an example from South India.
AU:  Harris-N
SO:  Contributions to Mineralogy and Petrology. 76; 2, Pages 229-233. 1981. 
PB:  Springer International. Heidelberg-New York, International. 1981.
PY:  1981
AN:  1982-059032

Record 333 of 393 in GeoRef Disc 2: 1975-1984

TI:  Corundum occurrences around Bhopalratnam, Bastar District, Madhya Pradesh.
AU:  Tripathi-C; Dutta-S-M
BK:  In: Symposium on three decades of developments in petrology, mineralogy and petrochemistry in India; abstracts.
BA:  Anonymous
SO:  Pages 135. 1981. 
PB:  Geol. Surv. India. Jaipur, India. 1981.
PY:  1981
AN:  1983-035593

Record 334 of 393 in GeoRef Disc 2: 1975-1984

TI:  Petrology of the Elk Creek and Bozeman corundum deposits, Madison and Gallatin counties, Montana.
AU:  Bakken-Barbara-M
BK:  In: Rocky Mountain Section, the Geological Society of America, 34th annual meeting.
BA:  Kolm-Kenneth-E (chairperson)
SO:  Abstracts with Programs - Geological Society of America. 13; 4, Pages 190. 1981. 
PB:  Geological Society of America (GSA). Boulder, CO, United States. 1981.
PY:  1981
AN:  1983-052909

Record 335 of 393 in GeoRef Disc 2: 1975-1984

TI:  The reaction corundum + dolomite = spinel + calcite.
AU:  Thordarsson-H
BK:  In: Symposium on experiment and theory in geology.
BA:  Anonymous
SO:  Geologiska Foereningen i Stockholm Foerhandlingar. 103; 1, Pages 127-128. 1981. 
PB:  Geological Society of Sweden. Stockholm, Sweden. 1981.
PY:  1981
AN:  1984-014102

Record 336 of 393 in GeoRef Disc 2: 1975-1984

TI:  The first mineral was condensed in a solar system.
AU:  Bar-Matthews-Miryam
BK:  In: Geology of the Golan Heights (central theme); annual meeting 1981.
BA:  Anonymous
SO:  1981; Pages 1-2. 1981. 
PB:  Isr. Geol. Soc., Israel. 1981.
PY:  1981
AN:  1984-019811

Record 337 of 393 in GeoRef Disc 2: 1975-1984

TI:  The melting phenomenon of the plagioclase feldspars II.
AU:  Smith-Michael-P; Philpotts-John-A
BK:  In: The Geological Society of America, 94th annual meeting.
SO:  Abstracts with Programs - Geological Society of America. 13; 7, Pages 557. 1981. 
PB:  Geological Society of America (GSA). Boulder, CO, United States. 1981.
PY:  1981
AN:  1984-026358

Record 338 of 393 in GeoRef Disc 2: 1975-1984

TI:  Quantitative Erfassung des Phasenwachstums in oxidischen Stoffsystemen mit Hilfe der Elektronenstrahl-Mikrobereichs-Analyse; Teil III, Reaktionen im System SiO (sub 2) -Al (sub 2) O (sub 3) bei Subsolidustemperaturen (1)
Translated Title:  Quantitative determination of phase growth in the oxide system using electron probe analysis; III, Reactions in the system SiO (sub 2) -Al (sub 2) O (sub 3) at lower temperature than the solidus.
AU:  Weisweiler-W
SO:  Sprechsaal (1976). 114; 6, Pages 450-454. 1981. 
PB:  Verlag des Sprechsaal Mueller & Schmidt. Coburg, Federal Republic of Germany. 1981.
PY:  1981
AN:  1985-013042

Record 339 of 393 in GeoRef Disc 2: 1975-1984

TI:  Interdiffusion studies in minerals with the corundum structure; Al (sub 2) O (sub 3) -Cr (sub 2) O (sub 3) .
AU:  Freer-R
BK:  In: Progress in experimental petrology, Fifth progress report of research supported by N.E.R.C. 1978-1980.
BA:  Ford-C-E (editor)
SO:  Progress in Experimental Petrology. 5; Pages 166-170. 1981. 
PB:  Natural Environment Research Council. London, United Kingdom. 1981.
PY:  1981
AN:  1986-044975

Record 340 of 393 in GeoRef Disc 2: 1975-1984

TI:  Korund-Orientierung am Gabbrokontakt (Seeheim, Bl. 6217 Zwingenberg a.d. Bergstrasse, Hessen)
Translated Title:  Corundum orientation at the gabbro contact (Seeheim, sheet 6217 Zwingenberg/ Bergstrasse), Hesse.
AU:  Krystosek-K; Paulitsch-P
SO:  Geologisches Jahrbuch Hessen. 109; Pages 133-136. 1981. 
PB:  Hessisches Landesamt fuer Bodenforschung. Wiesbaden, Federal Republic of Germany. 1981.
PY:  1981
AN:  1986-084310

Record 341 of 393 in GeoRef Disc 2: 1975-1984

TI:  Corundum-fuchsite rocks in greenstone belts of southern Africa; petrology, geochemistry, and possible origin.
AU:  Schreyer-W; Werding-G; Abraham-K
SO:  Journal of Petrology. 22; 2, Pages 191-231. 1981. 
PB:  Clarendon Press. Oxford, United Kingdom. 1981.
PY:  1981
AN:  1987-032600

Record 342 of 393 in GeoRef Disc 2: 1975-1984

TI:  Granitoids in the middle of Himalaya and Gangdise Mountains, Xizang.
AU:  Jin-Chengwei
SO:  Petrological Research. 1; 1, Pages 81-95. 1981. 
PB:  Institute of Geology Academia Sinica. Beijing, China. 1981.
PY:  1981
AB:  In southern xizang granitoids are widely distributed. The area of their exposures can be divided into two rock belts: the Gangdise and the Himalaya from north to south. The Gangdise granite belt is composed of Xoggula-Yangbajain-Chala (XYC) two-mica gneissic granite zone in north and the Nymling-Quxu (NQ) granite batholith zone in south. In XYC zone granites represent mainly two mica granite, biotite granite and alkali feldspar granite. Their K-Ar ages are 40-20 m.y.. The NQ batholith, which consists mainly of two-pyroxene gabbro, diorite, quartz diorite, quartz monzodiorite, granodiorite, monzogranite, hornblende granite and alkali feldspar leucogranite, is a complex intruded in several periods and stages. The radiometric dating shows that the age of the intrusion is 130-20 m.y. mainly 90-40 m.y. Six samples from Qu xu granodiorite give us a Rb-Sr whole rock isochron at 52.40+ or -11.75 m.y. (initial (super 87) Sr/ (super 88) Sr = 0.70523+ or -0.00057). Seven samples from Gurum hornblende granite give us a Rb-Sr whole rock isochron at 55.76+ or -9.95 m.y. (initial (super 87) Sr/ (super 86) Sr = 0.70572+ or -0.00012) and mineral isochron (biotite and feldspar) at 59.40+ or -0.47 m.y. (initial (super 87) Sr/ (super 86) Sr = 0.70534+ or -0.00046). Their characteristic accessory minerals are sphene, zircon, allanite, magnetite etc. The Lhagoi-Kangri two-mica gneissic monzonitic granite in northern zone of the Himalaya granite belt occurs usually as domes formed by diapirism and has strong migmatization at its margin. The-K-Ar age of Lhagoi-Kangri granites is 50-20 m.y. Eight samples from Kangmar gneissic granite give us a Rb-Sr whole rock isochron at 434.7+ or -37.3 m.y. (initial (super 87) Sr/ (super 86) Sr = 0.72072+ or -0.00087). K-Ar ages of tourmaline-muscovite granite in the High Himalaya zone is 30-10 m.y. The granite massives have accompanied with a large-scale regional migmatization. They are simple in petrography and small in size. The accessory minerals of the Himalaya granites are mainly tourmaline, garnet, sillimanite and topaz. Basing on the presented data author suggests that the Cretaceous-Eocene granitoids was formed by partial melting of the upper mantle and lower crust. Beside the above mentioned, there are other main characteristics: samples points trend towards the Ab end in the Or-Ab-Q diagram; the mean atomic weights, 20.9, are more than those of general granites; Norm of the granites usually contains diopside, no corundum; the average Na (sub 2) O/K (sub 2) O is 1.82; there is hornblende mode, not muscovite; sample points plot in hornblende-biotite-plagioclase region of Al-K-Na-Ca-Fe (super 2+) +Mg diagram under plagioclase-biotite line; the age of the batholith with complex composition is younger from south to north and the ratio K (sub 2) O/Si (sub 2) O increases; The granites are remarkably richer in Cu, V, Sc among the trace elements; initial (super 87) Sr/ (super 86) Sr is 0.7047-0.7057. These granites belong to I-type granite in accordance with the White and Chappeli's classification. The Eocene-Pliocene leucogranites in Gangdise and Himalaya were probably formed by the partial melting of the upper crust. The plotting point are concentrated near the eutectic point in Or-Ab-Q diagram. Their mean atomic weights are 20.4-20.6. There is higher corundum in norm (0.5-6.0%), and mode minerals are muscovite, garnet, sillimanite, etc. Their Na (sub 2) O/K (sub 2) O ratio is lower (average 0.87) and Be, B, Li, etc. is higher. The sample points are concentrated in muscovite-plagioclase-biotite region upper plagioclase-biotite line. Initial (super 87) Sr/ (super 86) Sr is 0.7186-0.7490. These granites belong undoubtedly to S-type granite. We suggested a model of three stage process--continent convergence, continent collision and intracontinent convergence--to explain the genesis of Gangdise and Himalaya granites.
AN:  1999-039871

Record 343 of 393 in GeoRef Disc 2: 1975-1984

TI:  Equilibria in the system Al (sub 2) O (sub 3) -SiO (sub 2) -H (sub 2) O and some general implications for alteration/ mineralization processes.
AU:  Hemley-J-J; Montoya-J-W; Marinenko-J-W; Luce-R-W
SO:  Economic Geology and the Bulletin of the Society of Economic Geologists. 75; 2, Pages 210-228. 1980. 
PB:  Economic Geology Publishing Company. Lancaster, PA, United States. 1980.
PY:  1980
AN:  1980-033803

Record 344 of 393 in GeoRef Disc 2: 1975-1984

TI:  The spinel- and corundum-bearing basic intrusion of Drahotin, Southwest Bohemia.
AU:  Vejnar-Zdenek

BK:  In: Krystalinikum; contributions to the geology and petrology of crystalline complexes.
BA:  Zoubek-Vladimir (editor)
SO:  Krystalinikum. 15, Pages 33-54. 1980. 
PB:  Ceskoslovenska Akademie Ved. Prague, Czechoslovakia. 1980.
PY:  1980
AN:  1982-007467

Record 345 of 393 in GeoRef Disc 2: 1975-1984

TI:  A corundum-rich inclusion in Murchison.
AU:  Grossman-L; Bar-Matthews-M; Hutcheon-I-D; MacPherson-G-J; Tanaka-T; Kawabe-I
BK:  In: Abstracts of papers presented at the 43rd annual meeting of the Meteoritical Society.
BA:  Moore-Carleton-B (editor)
SO:  Meteoritics. 15; 4, Pages 296-297. 1980. 
PB:  Arizona State University, Center for Meteorite Studies. Tempe, AZ, United States. 1980.
PY:  1980
AN:  1982-035271

Record 346 of 393 in GeoRef Disc 2: 1975-1984

BK:  Petrology and chemistry of the Elk Creek and Bozeman corundum deposits, Madison and Gallatin counties, Montana.
BA:  Bakken-Barbara-M
PY:  1980
DG:  Master's
DI:  University of Washington. Seattle, WA, United States. Pages: 69. 1980.
AN:  1992-055823

Record 347 of 393 in GeoRef Disc 2: 1975-1984

TI:  Thermally overprinted Dalradian rocks near Cleggan, Connemara, western Ireland.
AU:  Ferguson-C-C; Stewart-D-J
SO:  Proceedings of the Geologists' Association. 90, Parts 1-2; Pages 43-50. 1979. 
PB:  Geologists' Association. London, United Kingdom. 1979.
PY:  1979
AN:  1979-026605

Record 348 of 393 in GeoRef Disc 2: 1975-1984

TI:  The origin of corundum gneiss in the Cherry Creek Group, Ruby Range, Montana.
AU:  Haartz-E-R
SO:  Northwest Geology. 8; Pages 47-52. 1979. 
PB:  University of Montana, Department of Geology. Missoula, MT, United States. 1979.
PY:  1979
AN:  1980-003471

Record 349 of 393 in GeoRef Disc 2: 1975-1984

TI:  A reconnaissance of the system CaFe (super 3+) AlSiO (sub 6) -CaTiAl (sub 2) O (sub 6) .
AU:  Onuma-K; Akasaka-M
SO:  Journal of the Faculty of Science, Hokkaido University, Series 4: Geology and Mineralogy. 19; 1-2, Pages 29-35. 1979. 
PB:  Hokkaido University, Faculty of Science. Sapporo, Japan. 1979.
PY:  1979
AN:  1980-008031

Record 350 of 393 in GeoRef Disc 2: 1975-1984

TI:  Partial fusion and magma hybridization, Cortlandt Complex, New York.
AU:  Tracy-R-J; Thompson-A-B
SO:  Eos, Transactions, American Geophysical Union. 60; 18, Pages 411. 1979. 
PB:  American Geophysical Union. Washington, DC, United States. 1979.
PY:  1979
AN:  1980-010251

Record 351 of 393 in GeoRef Disc 2: 1975-1984

TI:  Pyrophyllite shales from South Africa.
AU:  Hayashi-H
BK:  In: Professor Takeshi Inoue memorial volume.
SO:  Akita Daigaku Kozan Gakubu, Chika Shigen Kenkyu Shisetsu Hokoku = Report of the Research Institute of Underground Resources, Mining College, Akita University. 45, Pages 110-123. 1979. 
PB:  Akita Daigaku Kozan Gakubu, Chika Shigen Kenkyu Shisetsu. Akita, Japan. 1979.
PY:  1979
AN:  1980-045739

Record 352 of 393 in GeoRef Disc 2: 1975-1984

BK:  Petrology and origin of the Camp Creek corundum deposit, Southwest Ruby Range, Montana.
BA:  Haartz-Eric-R
PY:  1979
DG:  Master's
DI:  University of Montana. Missoula, MT, United States. Pages: 53. 1979.
AN:  1981-002693

Record 353 of 393 in GeoRef Disc 2: 1975-1984

TI:  Margarite in kyanite- and corundum-bearing anorthosite, amphibolite, and hornblendite from central Fiordland, New Zealand.
AU:  Gibson-G-M
SO:  Contributions to Mineralogy and Petrology. 68; 2, Pages 171-179. 1979. 
PB:  Springer International. Heidelberg-New York, International. 1979.
PY:  1979
AN:  1982-048658

Record 354 of 393 in GeoRef Disc 2: 1975-1984

BK:  Precambrian geology of the Hottah Lake area, District of Mackenzie, N.W.T.
BA:  Violette-Benoit
PY:  1979
DG:  Bachelor's
DI:  Univ. of Ottawa. Ottawa, ON, Canada. 1979.
AN:  1983-054509

Record 355 of 393 in GeoRef Disc 2: 1975-1984

TI:  Mineralogiya korundovykh plagioklazitov Yugo-Zapadnogo Pamira
Translated Title:  Mineralogy of plagioclase and corundum in the southwestern Pamirs.
AU:  Kiselev-V-I
SO:  Mineralogiya Tadzhikistana. 4; Pages 175-184. 1979. 
PB:  Akademiya Nauk Tadzhikskoy SSR, Takzhikskoye Otdeleniye Vsesoyuznogo Mineralogicheskogo Obshchestva. Dushanbe, USSR. 1979.
PY:  1979
AN:  1984-052581

Record 356 of 393 in GeoRef Disc 2: 1975-1984

TI:  Parageneticheskiy analiz mineral'nykh assotsiatsiy v korundovykh plagioklazitakh Yugo-Zapadnogo Pamira
Translated Title:  Paragenesis analysis of mineral associations of corundum and plagioclase in the southwestern Pamirs.
AU:  Kiselev-V-I
SO:  Mineralogiya Tadzhikistana. 4; Pages 185-192. 1979. 
PB:  Akademiya Nauk Tadzhikskoy SSR, Takzhikskoye Otdeleniye Vsesoyuznogo Mineralogicheskogo Obshchestva. Dushanbe, USSR. 1979.
PY:  1979
AN:  1984-052582

Record 357 of 393 in GeoRef Disc 2: 1975-1984

TI:  Geologic and tectonic position of diamond-bearing basalts of Kamchatka.
AU:  Kaminskiy-F-V; Patoka-M-G; Sheymovich-V-S
SO:  Transactions (Doklady) of the U.S.S.R. Academy of Sciences: Earth Science Sections. 246; 1-6, Pages 55-58. 1979. 
PB:  Scripta Publishing. Silver Spring, MD, United States. 1979.
PY:  1979
AN:  1985-054472

Record 358 of 393 in GeoRef Disc 2: 1975-1984

TI:  Composition of biotites in igneous rocks.
AU:  Sobolev-V-S; Ushakova-Ye-N
SO:  Transactions (Doklady) of the U.S.S.R. Academy of Sciences: Earth Science Sections. 246; 1-6, Pages 116-118. 1979. 
PB:  Scripta Publishing. Silver Spring, MD, United States. 1979.
PY:  1979
AN:  1985-054491

Record 359 of 393 in GeoRef Disc 2: 1975-1984

TI:  A model for the formation and crystallization of corundum-normative calc-alkaline magmas through amphibole fractionation; a discussion.
AU:  Green-T-H; Cawthorn-R-G; Brown-P-A
SO:  Journal of Geology. 86; 2, Pages 269-275. 1978. 
PB:  University of Chicago Press. Chicago, IL, United States. 1978.
PY:  1978
AN:  1978-021986

Record 360 of 393 in GeoRef Disc 2: 1975-1984

TI:  A spinel-forming reaction in aluminous dolomitic marbles of Naxos, Greece.
AU:  Jansen-J-B-H; Feenstra-A; Schuiling-R-D
SO:  Neues Jahrbuch fuer Mineralogie. Monatshefte. 4, Pages 145-158. 1978. 
PB:  E. Schweizerbart'sche Verlagsbuchhandlung. Stuttgart, Federal Republic of Germany. 1978.
PY:  1978
AN:  1978-039412

Record 361 of 393 in GeoRef Disc 2: 1975-1984

TI:  Liquidus phase relations on the join diopside-forsterite-anorthite from 1 atm to 20 kbar; their bearing on the generation and crystallization of basaltic magma.
AU:  Presnall-D-C; Dixon-S-A; Dixon-J-R; O-Donnell-T-H; Brenner-N-L; Schrock-R-L; Dycus-D-W
SO:  Contributions to Mineralogy and Petrology. 66; 2, Pages 203-220. 1978. 
PB:  Springer International. Heidelberg-New York, International. 1978.
PY:  1978
AB:  In the system CaO-MgO-Al2O3-SiO2, the tetrahedron CaMgSi2O6 (di) - Mg2SiO4 (fo) - SiO2 - CaAl2SiO6 (CaTs) forms a simplified basalt tetrahedron, and within this tetrahedron, the plane di-fo-CaAl2Si2O8 (an) separates simplified tholeiitic from alkalic basalts. Liquidus phase relations on this join have been studied at 1 atm and at 7, 10, 15, and 20 kbar. The temperature maximum on the 1 atm isobaric quaternary univariant line along which forsterite, diopside, anorthite, and liquid are in equilibrium lies to the SiO2-rich side of the join di-fo an. The isobaric quaternary invariant point at which forsterite, diopside, anorthite, spinel, and liquid are in equilibrium passes, with increasing pressure, from the silica-poor to the silica-rich side of the join di-fo-an, which causes the piercing points on this join to change from forsterite + diopside + anorthite + liquid and forsterite + spinel + anorthite + liquid below 5 kbar to forsterite + diopside + spinel + liquid and diopside + spinel + anorthite + liquid above 5 kbar. As pressure increases, the forsterite and anorthite fields contract and the diopside and corundum fields expand. The anorthite primary phase field disappears entirely from the join di-fo-an between 15 and 20 kbar. Below about 4 kbar, the join di-fo-an represents, in simplified form, a thermal divide between alkalic and tholeiitic basalts. From about 4 to at least 12 kbar, alkalic basalts can produce tholeiitic basalts by fractional crystallization, and at pressures above about 12 kbar it is possible for alkalic basalt to be produced from oceanite by crystallization of both olivine and orthopyroxene. If alkalic basalts are primary melts from a lherzolite mantle, they must be produced at high pressures, probably greater than about 12 kbar.
AN:  1979-007818

Record 362 of 393 in GeoRef Disc 2: 1975-1984

TI:  Korundstaebchen; Das Korundstaebchen als neuer Arbeitshelfer
Translated Title:  Corundum rods; the corundum rod as a new technique.
AU:  Ballczo-H
SO:  Lapis (Muenchen). 3; 11, Pages 20-21. 1978. 
PB:  Weise. Munich, Federal Republic of Germany. 1978.
PY:  1978
AN:  1979-008820

Record 363 of 393 in GeoRef Disc 2: 1975-1984

TI:  A pyrope-spinel xenolith from Colorado Plateau kimberlite; first known North American occurrence.
AU:  Padovani-E-R; Tracy-R-J
SO:  Abstracts with Programs - Geological Society of America. 10; 7, Pages 466. 1978. 
PB:  Geological Society of America (GSA). Boulder, CO, United States. 1978.
PY:  1978
AN:  1979-010403

Record 364 of 393 in GeoRef Disc 2: 1975-1984

BK:  On an Archaean marundite occurrence (corundum-margarite rock) in the Barberton Mountain Land, eastern Transvaal.
BA:  Anhaeusser-C-R
SO:  Information Circular - University of the Witwatersrand, Economic Geology Research Unit. 119, 1978. 
PB:  University of the Witwatersrand, Economic Geology Research Unit. Johannesburg, South Africa. Pages: 8. 1978.
PY:  1978
AN:  1979-014224

Record 365 of 393 in GeoRef Disc 2: 1975-1984

TI:  Termodinamicheskiy analiz nekotorykh mineral'nykh ravnovesiy v sisteme MgO-Al (sub 2) O (sub 3) -SiO (sub 2) i petrologicheskiye vyvody
Translated Title:  Thermodynamic analysis of certain mineral balances in the system MgO-Al (sub 2) O (sub 3) -SiO (sub 2) and petrologic conclusions.
AU:  Kolesnik-Yu-N
BK:  In: Problemy petrologii zemnoy kory i verkhney mantii.
BA:  Dobretsov-N-L (editor); Kepezhinskas-K-B (editor); Kuznetsov-V-A (editor); Reverdatto-V-V (editor); Khlestov-V-V (editor); Chepurov-A-I (editor)
SO:  Trudy Instituta Geologii i Geofiziki (Novosibirsk). 403, Pages 130-139. 1978. 
PB:  Nauka, Sibirskoye Otdeleniye Instituta Geologii i Geofiziki. Novosibirsk, USSR. 1978.
PY:  1978
AN:  1979-038657

Record 366 of 393 in GeoRef Disc 2: 1975-1984

TI:  On an Archaean marundite occurrence in the Barberton Mountain Land, eastern Transvaal.
AU:  Anhaeusser-C-R
SO:  Verhandelinge van die Geologiese Vereniging van Suid Afrika = Transactions of the Geological Society of South Africa. 81; 2, Pages 211-218. 1978. 
PB:  Geological Society of South Africa. Marshalltown, South Africa. 1978.
PY:  1978
AN:  1980-002730

Record 367 of 393 in GeoRef Disc 2: 1975-1984

TI:  Un cas peu frequent de retromorphose du disthene primaire dans une eclogite amphibolitisee du Bas-Limousin
Translated Title:  An infrequent case of retromorphism of primary kyanite in an amphibolitized eclogite in Bas-Limousin.
AU:  Santallier-Danielle
SO:  Comptes Rendus Hebdomadaires des Seances de l'Academie des Sciences, Serie D: Sciences Naturelles. 286; 11, Pages 819-820. 1978. 
PB:  Gauthier-Villars. Paris, France. 1978.
PY:  1978
AN:  1981-050271

Record 368 of 393 in GeoRef Disc 2: 1975-1984

TI:  Some characteristics of the corundum-bearing basalt in Thailand ?.
AU:  Vichit-Pongsak; Vudhichativanich-Supatra; Hansawek-Rak
BK:  In: Geology and mineral resources of Thailand; special issue for III GEOSEA.
BA:  Sampattavanija-Suvit (editor)
SO:  Warasan Samakhom Thoraniwitthaya Haeng Prathetthai = Journal of the Geological Society of Thailand. 3; 1, Pages M4.1-M4.38. 1978. 
PB:  Geological Society of Thailand, Department of Mineral Resources. Bangkok, Thailand. 1978.
PY:  1978
AN:  1982-026463

Record 369 of 393 in GeoRef Disc 2: 1975-1984

TI:  Desilitsirovannyye pegmatity s dravitom i korundom (Yugo-Zapadnyy Pamir)
Translated Title:  Desilicified pegmatites with dravite and corundum from the southwestern Pamirs.
AU:  Rossovskiy-L-N; Konovalenko-S-I; Bovin-Yu-P
SO:  Izvestiya Akademii Nauk SSSR. Seriya Geologicheskaya. 1978; 11, Pages 40-53. 1978. 
PB:  Akademiya Nauk SSSR. Moscow, USSR. 1978.
PY:  1978
AN:  1984-007308

Record 370 of 393 in GeoRef Disc 2: 1975-1984

TI:  Une nouvelle eclogite a disthene et corindon primaires dans les complexes leptyno-amphiboliques du Massif central francais (Levezou, Rouergue)
Translated Title:  A new kyanitic and primary-corundum-bearing eclogite from the leptyno-amphibolic complexes of the Central Massif, Levezou, Rouergue, France.
AU:  Nicollet-C
SO:  Bulletin de la Societe Francaise de Mineralogie et de Cristallographie. 100; 6, Pages 334-337. 1977. 
PB:  Masson. Paris, France. 1977.
PY:  1977
AN:  1978-016625

Record 371 of 393 in GeoRef Disc 2: 1975-1984

TI:  The Corundum Hill Dunite, Macon County, North Carolina.
AU:  Yurkovich-S-P
SO:  Southeastern Geology. 19; 1, Pages 55-68. 1977. 
PB:  Duke University, Department of Geology. Durham, NC, United States. 1977.
PY:  1977
AN:  1978-018722

Record 372 of 393 in GeoRef Disc 2: 1975-1984

TI:  Isograds of kyanite, chloritoid, corundum, and high-alumina equilibria in greenschist metamorphism (Patom Highlands).
AU:  Korikovskiy-S-P; Boronikhin-V-A
SO:  International Geology Review. 19; 6, Pages 703-708. 1977. 
PB:  Winston & Son. Silver Spring, MD, United States. 1977.
PY:  1977
AN:  1978-021657

Record 373 of 393 in GeoRef Disc 2: 1975-1984

TI:  Zakonomernosti raspredeleniya aktsessornykh mineralov v granitoidakh Vitimo-Kondinskogo mezhdurech'ya; Zapadnoye Zabaykal'ye
Translated Title:  Regularities in the distribution of accessory minerals in the granitoids of the Vitim-Kondian region, western Baikal region.
AU:  Slipchenko-V-A
BK:  In: Voprosy prikladnoy geokhimii i petrofiziki; sbornik statey.
BA:  Tolstoy-M-I (editor); Gasanov-Yu-L (editor); Belevtsev-Ya-N (editor); Vovk-I-F (editor); Galetskiy-L-S (editor); Yegorov-Yu-P (editor); Zhukov-N-N (editor); Kravchenko-Yu-B (editor); Kulikovskiy-V-K (editor); Lebedev-T-S (editor); Mitskevich-B-F (editor); Ostafiychuk-I-M (editor); Pivovar-I-S (editor); Povarennykh-A-S (editor); Sobotovich-E-B (editor); Sukhorada-A-V (editor)
SO:  Pages 88-101. 1977. 
PB:  Izd. Vishcha Shkola. Kiev, USSR. 1977.
PY:  1977
AN:  1979-027512

Record 374 of 393 in GeoRef Disc 2: 1975-1984

TI:  Corundum plagioclasite of the southwestern Pamirs.
AU:  Rossovskiy-L-N; Konovalenko-S-I
SO:  Transactions (Doklady) of the U.S.S.R. Academy of Sciences: Earth Science Sections. 235; 1-6, Pages 145-147. 1977. 
PB:  Scripta Publishing. Silver Spring, MD, United States. 1977.
PY:  1977
AN:  1979-038891

Record 375 of 393 in GeoRef Disc 2: 1975-1984

TI:  The Posey Canyon Shale; a Pliocene lacustrine deposit of the Ridge Basin, southern California.
AU:  Irvine-P-J
BK:  In: Geological guidebook to the Ridge Basin; northwestern Los Angeles County, California.
BA:  French-J (chairperson); Woyski-M-S (editor)
SO:  Pages 28-30. 1977. 
PB:  South Coast Geol. Soc.. Irvine, Calif., United States. 1977.
PY:  1977
AN:  1980-019866

Record 376 of 393 in GeoRef Disc 2: 1975-1984

TI:  Origin of corundum-normative intrusive and extrusive magmas.
AU:  Cawthorn-R-G; Strong-D-F; Brown-P-A
SO:  Nature (London). 259; 5539, Pages 102-104. 1976. 
PB:  Macmillan Journals. London, United Kingdom. 1976.
PY:  1976
AN:  1976-031007

Record 377 of 393 in GeoRef Disc 2: 1975-1984

TI:  Phase relations of basalts in their melting ranges at P (sub H2O) = 5 kb; Part II, Melt compositions.
AU:  Helz-R-T
SO:  Journal of Petrology. 17; 2, Pages 139-193. 1976. 
PB:  Clarendon Press. Oxford, United Kingdom. 1976.
PY:  1976
AB:  This paper describes the melting relations of three basalts, a Picture Gorge tholeiite, the 1921 Kilauea olivine tholeiite, and the 1801 Hualalai alkali basalt, at 5 kb water pressure, 680-1045 degrees C, at the oxygen fugacities of the quartz-fayalite-magnetite (QFM) and hematite-magnetite (HM) buffer. All melts produced within the hornblende stability field are strongly quartzo-feldspathic. All are quartz-normative, including those from the alkali basalt, and all but two of the melts are corundum-normative. Melt composition shows very little dependence on oxygen fugacity within the hornblende stability field, as MgO and FeO contents are very low. When hornblende begins to melt extensively (1000-1045 degrees C), the TiO2, FeO, and MgO contents of the melt increase abruptly. In this range, melts formed on the HM buffer have much higher Mg/Fe ratios and lower TiO2 than melts formed on the QFM buffer. Melt composition is also quite insensitive to changes in basalt composition, within the hornblende stability field. The chief exception is the Na/Ca ratio, which varies directly with Na/Ca in the starting basalt. When projected into the Ab-An-Or-Qz quaternary system, all melts produced follow a rather narrow spiral path through the tetrahedron, they descend from the An corner, moving toward Qz at constant Ab/Or, moving toward Or only when plagioclase:quartz begin to precipitate. The melting behavior of hornblende, plagioclase, and augite in these experiments has been examined closely, with the following results: successive partial melts may differ from each other by compositional increments which are very different in composition from the minerals contributing to the melt in the temperature interval under consideration. These increments can almost never be expressed solely in terms of members of the one or two mineral solid solutions from which they are actually derived. In a few cases the increments cannot be expressed in terms of any reasonable combination of minerals. This pattern contrasts markedly with that observed in fractional crystallization, in which the difference between successive melts must always correspond to present or possible phenocryst minerals. The contrast implies that magma series generated by any kind of melting process, equilibrium or fractional, should be recognizably different from series generated by fractional crystallization, if minerals like hornblende or pyroxene are involved.
AN:  1976-032317

Record 378 of 393 in GeoRef Disc 2: 1975-1984

TI:  Petrology of the Corundum Hill alpine peridotite, Macon County, North Carolina.
AU:  Yurkovich-S-P
SO:  Abstracts with Programs - Geological Society of America. 8; 2, Pages 306. 1976. 
PB:  Geological Society of America (GSA). Boulder, CO, United States. 1976.
PY:  1976
AN:  1977-043438

Record 379 of 393 in GeoRef Disc 2: 1975-1984

TI:  O rezul'tatakh primeneniya dvukhfaktornogo dispersionnogo analiza dlya obrabotki dannykh mineralogicheskogo, khimicheskogo i spektral'nogo izucheniya nizhnedevonskikh porod Litvy
Translated Title:  Application of a two-factor dispersion analysis in the treatment of mineralogical, chemical and spectral analysis data from Devonian rocks in Lithuania.
AU:  Narbutas-V
BK:  In: Metodika i interpretatsiya rezul'tatov mineralogicheskikh i geokhimicheskikh issledovaniy.
BA:  Narbutas-V (editor)
SO:  Pages 18-21. 1976. 
PB:  Izd. Mokslas. Vilna, USSR. 1976.
PY:  1976
AN:  1978-000343

Record 380 of 393 in GeoRef Disc 2: 1975-1984

TI:  Sur une paragenese a pargasite-gedrite-disthene-corindon dans les metagabbros des massifs basiques et ultrabasiques differencies de Limousin (Massif Central francais)
Translated Title:  On a paragenesis of pargasite-gedrite-kyanite-corundum in the metagabbros of different basic and ultrabasic massifs of Limousin, French Central Massif.
AU:  Piboule-M; Menot-R-P
SO:  Comptes Rendus Hebdomadaires des Seances de l'Academie des Sciences, Serie D: Sciences Naturelles. 282; 2, Pages 141-144. 1976. 
PB:  Gauthier-Villars. Paris, France. 1976.
PY:  1976
AN:  1978-004941

Record 381 of 393 in GeoRef Disc 2: 1975-1984

TI:  Corundum-staurolite-hornblende schists of the Belomorskiy Complex.
AU:  Lebedev-V-I; Kalmykova-N-A; Nagaytsev-Yu-V
SO:  International Geology Review. 18; 6, Pages 653-662. 1976. 
PB:  Winston & Son. Silver Spring, MD, United States. 1976.
PY:  1976
AN:  1978-005741

Record 382 of 393 in GeoRef Disc 2: 1975-1984

TI:  Bauxitization in the geologic history of the Earth and the basic similarity between exogenic processes in the Precambrian and the Phanerozoic.
AU:  Sidorenko-A-V; Tenyakov-V-A
SO:  Transactions (Doklady) of the U.S.S.R. Academy of Sciences: Earth Science Sections. 226; 1-6, Pages 85-87. 1976. 
PB:  Scripta Publishing. Silver Spring, MD, United States. 1976.
PY:  1976
AN:  1978-020947

Record 383 of 393 in GeoRef Disc 2: 1975-1984

TI:  Izogrady kianita, khloritoida, korunda v vysokoglinozemistyye ravnovesiya v zelenoslantsevoy fatsii metamorfizma (Patomskoye nagor'ye)
Translated Title:  Kyanite, chloritoid and corundum isograds and high-alumina balance in greenschist-facies metamorphic rocks from the Patom Plateau.
AU:  Korikovskiy-S-P; Voronikhin-V-A
SO:  Izvestiya Akademii Nauk SSSR. Seriya Geologicheskaya. 1976; 04, Pages 17-23. 1976. 
PB:  Akademiya Nauk SSSR. Moscow, USSR. 1976.
PY:  1976
AN:  1983-024361

Record 384 of 393 in GeoRef Disc 2: 1975-1984

TI:  Synthetic Mn (super 3+) -kyanite and viridine, (Al (sub 2-x) Mn (super 3+) (sub x) )SiO (sub 5) , in the system Al (sub 2) O (sub 3) -MnO (sub 2) -SiO (sub 2) .
AU:  Abs-Wurmbach-I; Langer-K
SO:  Contributions to Mineralogy and Petrology. 49; 1, Pages 21-38. 1975. 
PB:  Springer International. Heidelberg-New York, International. 1975.
PY:  1975
AN:  1975-018102

Record 385 of 393 in GeoRef Disc 2: 1975-1984

TI:  Solid-liquid equilibria involving spinels, ilmenite and pseudobrookite in the system "FeO"-Al (sub 2) O (sub 3) -TiO (sub 2) in contact with metallic iron.
AU:  Schreifels-W-A; Muan-A
BK:  In: Lunar Science VI, Part II, Abstracts.
SO:  Pages 718-719. 1975. 
PB:  Lunar Sci. Inst., Houston, Texas. 1975.
PY:  1975
AN:  1975-024257

Record 386 of 393 in GeoRef Disc 2: 1975-1984

TI:  Natural fluorine buffers in the system BeO-Al (sub 2) O (sub 3) -SiO (sub 2) -F (sub 2) O (sub -1) .
AU:  Burt-D-M
SO:  Eos, Transactions, American Geophysical Union. 56; 6, Pages 467. 1975. 
PB:  American Geophysical Union. Washington, DC, United States. 1975.
PY:  1975
AN:  1976-002493

Record 387 of 393 in GeoRef Disc 2: 1975-1984

TI:  High temperature heat content of silicate glasses and the partial molar heat capacities of oxide components of silicate melts between 298 degrees K and the glass transition.
AU:  Bacon-C-R
SO:  Abstracts with Programs - Geological Society of America. 7; 7, Pages 983-984. 1975. 
PB:  Geological Society of America (GSA). Boulder, CO, United States. 1975.
PY:  1975
AN:  1976-043822

Record 388 of 393 in GeoRef Disc 2: 1975-1984

TI:  Petrogenetic significance of normative corundum in calc-alkaline volcanic rock series.
AU:  Ujike-O
SO:  Ganseki Kobutsu Kosho Gakkai-Shi = Journal of the Japanese Association of Mineralogists, Petrologists and Economic Geologists. 70; 3, Pages 85-92. 1975. 
PB:  Nippon Ganseki Kobutsu Kosho Gakkai, c/o: Tohoku Daigaku Rigakubu. Sendai, Japan. 1975.
PY:  1975
AN:  1977-011784

Record 389 of 393 in GeoRef Disc 2: 1975-1984

TI:  Sapphire-bearing basaltic rocks from Queensland, Australia.
AU:  Stephenson-P-J
SO:  Eos, Transactions, American Geophysical Union. 56; 12, Fall annual meeting, Pages 1070. 1975. 
PB:  American Geophysical Union. Washington, DC, United States. 1975.
PY:  1975
AN:  1977-027379

Record 390 of 393 in GeoRef Disc 2: 1975-1984

TI:  Sapphirine and associated minerals from the kornerupine rock of Waldheim, Saxony.
AU:  Schreyer-W; Abraham-K; Behr-H-J
SO:  Neues Jahrbuch fuer Mineralogie. Abhandlungen. 126; 1, Pages 1-27. 1975. 
PB:  E. Schweizerbart'sche Verlagsbuchhandlung. Stuttgart, Federal Republic of Germany. 1975.
PY:  1975
AN:  1977-035445

Record 391 of 393 in GeoRef Disc 2: 1975-1984

TI:  Korundovyye siyenity kopi "Yubileynoy"
Translated Title:  Corundum syenites at the Yubileynoy mines.
AU:  Levin-V-Ya; Koroteyev-V-A; Zvonareva-G-K
BK:  In: Materialy k mineralogii Urala
Translated Title:  Data on the mineralogy of the Urals.
BA:  Popov-V-A (editor)
SO:  Trudy Il'menskogo Gosudarstvennogo Zapovednika. 13, Pages 44-49. 1975. 
PB:  Akademiya Nauk SSSR, Ural'skiy Nauchnyy Tsentr. Sverdlovsk, USSR. 1975.
PY:  1975
AN:  1981-057910

Record 392 of 393 in GeoRef Disc 2: 1975-1984

TI:  K mekhanizmu formirovaniya polevoshpatovykh ochkov vokrug kristallov korunda kopi "Yubileynoy" v Il'menskikh gorakh
Translated Title:  The formation mechanism of feldspar lenses around corundum crystals at the "Yubileynoy" mines in the Ilmen Mountains.
AU:  Popov-V-A; Popova-V-I
BK:  In: Materialy k mineralogii Urala
Translated Title:  Data on the mineralogy of the Urals.
BA:  Popov-V-A (editor)
SO:  Trudy Il'menskogo Gosudarstvennogo Zapovednika. 13, Pages 50-57. 1975. 
PB:  Akademiya Nauk SSSR, Ural'skiy Nauchnyy Tsentr. Sverdlovsk, USSR. 1975.
PY:  1975
AN:  1981-057911

Record 393 of 393 in GeoRef Disc 2: 1975-1984

TI:  Der Korund-Hercynit-Fels von Ploessberg
Translated Title:  The corundum-hercynite rocks of Ploessberg.
AU:  Propach-Giselher
BK:  In: Zur Mineralogie und Geologie der Oberpfalz
Translated Title:  Mineralogy and geology of the Upper Palatinate.
BA:  Strunz-Hugo (editor)
SO:  Der Aufschluss, Sonderheft. 26; Pages 65-80. 1975. 
PB:  Vereinigung der Freunde der Mineralogie und Geologie. Heidelberg, Federal Republic of Germany. 1975.
PY:  1975
AN:  1983-013003