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Rameshwar Rao, D.
- Felsic Granites vis-a-vis Leucosomes from the Shyok-Darbuk Section of the Shyok Suture Zone, Eastern Ladakh, India: A Geochemical Study
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Authors
Affiliations
1 Wadia Institute of Himalayan Geology, 33 General Mahadeo Singh Road, Dehradun 248 001, IN
2 Groundwater Surveys and Development Agency, Solapur 413 003, IN
1 Wadia Institute of Himalayan Geology, 33 General Mahadeo Singh Road, Dehradun 248 001, IN
2 Groundwater Surveys and Development Agency, Solapur 413 003, IN
Source
Current Science, Vol 108, No 2 (2015), Pagination: 198-204Abstract
The Shyok-Darbuk section of eastern Ladakh forms a part of the Shyok Suture Zone, and is dominantly comprised of Early Eocene orthogneisses and mafic enclaves, and Miocene felsic granites and migmatites. The aim of the present study is to establish genetic linkage between leucosome of the migmatites from mixed zone and the felsic granite in the Darbuk region (DFG). It is observed that, partial melting, with or without segregation of initial melts, seems to be the main cause for the generation of felsic melts as represented by leucosomes and felsic granites. Leucosomes are considered as felsic partial melts that were retained in the partially molten zone (migmatite), and that the complex intrusive networks of melt channels in the migmatite region are considered to merge and coalesce during their ascent to upper crustal levels resulting in stocks and plutons of felsic granites that are observed in the Darbuk region.Keywords
Darbuk Felsic Granite, Eastern Ladakh, Leucosomes, Migmatites, Shyok–Darbuk Section.Full Text
- Garnetiferous Metamorphic Rocks in Jaspa Granite, Himachal Pradesh, India:Implication of Tethyan Himalayan Metamorphism and Tectonics
Abstract Views :168 |
PDF Views:76
Authors
Affiliations
1 Wadia Institute of Himalayan Geology, 33 GMS Road, Dehradun 248 001, IN
1 Wadia Institute of Himalayan Geology, 33 GMS Road, Dehradun 248 001, IN
Source
Current Science, Vol 115, No 8 (2018), Pagination: 1576-1583Abstract
Studies on the magmatic enclaves, pelitic xenoliths and host Jaspa granite pluton outcropped in the Lahaul area, NW Himalaya, India illustrate that the rocks have undergone garnet-grade metamorphism. The P -T pseudosection modelling shows that the metamorphic mineral assemblage is stable in the P -T range ~4.5-7.3 kbar and ~440-500°C, matching quite well with the results obtained from the conventional geothermobarometers (5.7-8.6 kbar and 409-531°C). The observed garnet-grade metamorphism in and around the Jaspa pluton is proposed to be due to localized perturbation of high-temperature isotherms in the Tethys Himalaya, as a consequence of the Cenozoic tectono-thermal event during Himalayan orogeny. Further, the Haimanta group of Tethys Himalayan rocks in the Lahaul area has been interpreted to have attained right-way-up metamorphic field gradient.Keywords
Garnet-Grade Metamorphism, Granite Pluton, Magmatic Enclaves, Pelitic Xenoliths.Full Text
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