At 12:57 PM 7/4/01 +0200, you wrote:
>Listmembers,
> I am working on pseudotachylyte-like veins from a gabbro in the
>high-pressure zone of the Western Gneiss Region, Norway. These veins show
>fine-grained (1-100 micrometer) and highly skeletal or 'flowershaped'
>grains of grt, cpx, dol, omph, amph, and bi. Conventional
>geothermobarometry yield eclogite-facies conditions for assemblages in
>these veins.
> If anyone has suggestions to references concerning
>crystallization/recrystallization processes (both crystallization from a
>melt and metamorphic recrystallization) that may lead to the formation of
>highly skeletal, dendritic, or 'flowershaped' crystals, I would be very
>grateful.
> Many thanks, Mats.
> Mats G. Lund
> Mineralogical-Geological Museum,
> University of Oslo
> P.O. Box 1172 Blindern
> N-0318 Oslo, Norway
Classical (for basalts):
G.E. Lofgren, JGR 76, 5635-5648, 1971
-- , Am. J. Science 274, 243-273, 1974
-- , in R.B. Hargraves (ed), Physics of magmatic processes. Princeton UP,
487-551, 1980
-- , J. Petrology 24, 229-255, 1983
Also:
C.H. Donaldson, CMP 57, 187-213, 1976
Donaldson & Brown, EPSL 37, 81-89, 1977
Donaldson et al, Proc. 6th Lunar Sci. Conf. , 843-869, 1975
D. Walker et al., BGSA 87, 646-656, 1976
R.J. Kirkpatrick, Initial Rept DSDP, 46, 271-282, 1978
and check K/T boundary spherules, e.g.
F. Martinez Ruiz et al, Sedimentary Geology 113, 137-147, 1997 and refs
therein
spherules with unaltered skelettal cpx were drilled by DSDP hole 577
-------------------------------------
Frank F. Beunk
Institute of Earth Sciences, Dept. of Petrology, Vrije Universiteit
De Boelelaan 1085, 1081 HV Amsterdam, the Netherlands
phone +31-20-4447371
FAX +31-20-6462457
e-mail: [log in to unmask]
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