Dear Dr Singh,
There are a couple of tectonomagmatic events that I know of in the range 800-850. These affected the Amazonia craton in South America, (Hippertt & Davis 2000, Neves et al. 2000), the Antananarivo Block, central Madagascar (Kroner et al. 2000), South China (Li et al. 1999, Zhang et al. 1998), and are associated with rifting/mantle metasomatism in the western US (Beard & Glazner 1995) and eastern Africa (Hanson et al. 1994), and the Knoydartian Orogeny recorded in the Dalradian rocks of Scotland (Prave 1999, Highton et al. 1999, Rogers et al. 1998). There are also some ages in this range from Australian kimberlites (Ramsay et al 1994, Kent et al. 1998), and metamorphic rocks in the southern Appalachians (Su et al. 1994). I realise that this is a bit of a rag bag of events, but I hope that it will at least give you a start.
All the best,
Alan
TRACE-ELEMENT AND SR AND ND ISOTOPIC COMPOSITION OF MANTLE XENOLITHS FROM THE BIG-PINE VOLCANIC FIELD, CALIFORNIA
BEARD BL, GLAZNER AF
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
100: (B3) 4169-4179 MAR 10 1995
GEOLOGIC EVOLUTION OF THE NEOPROTEROZOIC ZAMBEZI OROGENIC BELT IN ZAMBIA
HANSON RE, WILSON TJ, MUNYANYIWA H
JOURNAL OF AFRICAN EARTH SCIENCES
18: (2) 135-150 FEB 1994
U-Pb zircon geochronology of migmatization in the northern Central Highlands: evidence for pre-Caledonian (Neoproterozoic) tectonometamorphism in the Grampian block, Scotland
Highton AJ, Hyslop EK, Noble SR
JOURNAL OF THE GEOLOGICAL SOCIETY
156: 1195-1204, Part 6 NOV 1999
Dome emplacement and formation of kilometre-scale synclines in a granite-greenstone terrain (Quadrilatero Ferrifero, southeastern Brazil)
Hippertt J, Davis B
PRECAMBRIAN RESEARCH
102: (1-2) 99-121 JUL 2000
Mineralogy and Ar-40/Ar-39 geochronology of orangeites (Group II kimberlites) from the Damodar Valley, eastern India
Kent RW, Kelley SP, Pringle MS
MINERALOGICAL MAGAZINE
62: (3) 313-323 JUN 1998
Age and magmatic history of the Antananarivo Block, central Madagascar, as derived from zircon geochronology and Nd isotopic systematics
Kroner A, Hegner E, Collins AS, Windley BF, Brewer TS, Razakamanana T, Pidgeon RT
AMERICAN JOURNAL OF SCIENCE
300: (4) 251-288 APR 2000
The breakup of Rodinia: did it start with a mantle plume beneath South China?
Li ZX, Li XH, Kinny PD, Wang J
EARTH AND PLANETARY SCIENCE LETTERS
173: (3) 171-181 NOV 30 1999
Intralithospheric differentiation and crustal growth: Evidence from the Borborema province, northeastern Brazil
Neves SP, Mariano G, Guimaraes IP, Da Silva AF, Melo SC
GEOLOGY
28: (6) 519-522 JUN 2000
The Neoproterozoic Dalradian Supergroup of Scotland: an alternative hypothesis
Prave AR
GEOLOGICAL MAGAZINE
136: (6) 609-617 NOV 1999
COMPOSITIONS OF GARNET AND SPINEL FROM THE ARIES DIAMONDIFEROUS KIMBERLITE PIPE, CENTRAL KIMBERLEY BLOCK, WESTERN-AUSTRALIA - IMPLICATIONS FOR EXPLORATION
RAMSAY RR, EDWARDS D, TAYLOR WR, ROCK NMS, GRIFFIN BJ
JOURNAL OF GEOCHEMICAL EXPLORATION
51: (1) 59-78 APR 1994
The structural setting and U-Pb geochronology of Knoydartian pegmatites in W Inverness-shire: evidence for Neoproterozoic tectonothermal events in the Moine of NW Scotland
Rogers G, Hyslop EK, Strachan RA, Paterson BA, Holdsworth RE
JOURNAL OF THE GEOLOGICAL SOCIETY
155: 685-696, Part 4 JUL 1998
PRECISE U-PB ZIRCON AGES OF NEOPROTEROZOIC PLUTONS IN THE SOUTHERN APPALACHIAN BLUE-RIDGE AND THEIR IMPLICATIONS FOR THE INITIAL RIFTING OF LAURENTIA
SU Q, GOLDBERG SA, FULLAGAR PD
PRECAMBRIAN RESEARCH
68: (1-2) 81-95 JUN 1994
The neodymium isotopic characteristic and geological significance of Kuokesu plagioclase amphibolites from the Kuruktag, Xinjiang, China
Zhang ZC, Guo ZJ, Liu SW, Zheng HF
CHINESE SCIENCE BULLETIN
43: (23) 2001-2005 DEC 1998
Dr. Alan P.M. Vaughan
Geological Sciences
British Antarctic Survey
High Cross
Madingley Rd.
Cambridge CB3 0ET
UK
Tel. -44-1223-221419
Fax -44-1223-362616
E-mail: [log in to unmask]
Web: www.antarctica.ac.uk
>>> Dr Sandeep Singh <[log in to unmask]> 04:36:37 25/08/00 >>>
Dear friend
Is there any Neoproterozoic magmatic activity related with some orogeny in
the world around 820-830 Ma. There is one felsic body in Himalaya which
correspond to this particular event. I am trying to relate them with the
global event, because there is no other event reported in Himalaya.
looking forward for hearing from you on this aspect.
Sandeep Singh
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