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Tripathy, S. K.
- Characteristics of Mesoproterozoic Felsic Meta-Volcanics from the Shillong Group of Rocks, Meghalaya, North East India
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Authors
Affiliations
1 Geological Survey of India, North Eastern Region, Shillong 793 003, IN
2 Department of Applied Geology, Dibrugarh University, Dibrugarh 786 004, IN
3 Regional Training Institute, Geological Survey of India, Eastern Region, Kolkata 700 091, IN
1 Geological Survey of India, North Eastern Region, Shillong 793 003, IN
2 Department of Applied Geology, Dibrugarh University, Dibrugarh 786 004, IN
3 Regional Training Institute, Geological Survey of India, Eastern Region, Kolkata 700 091, IN
Source
Current Science, Vol 118, No 7 (2020), Pagination: 1123-1128Abstract
Shillong Group comprises a thick meta-volcano-sedimentary sequence forming a part of Shillong Plateau and Mikir Hills. The litho variants of felsic meta-volcanics are characterized in detail based on their constituent material, textural variation, depositional feature and mode of eruption. Lava flows are characterized as porphyritic, spherulitic and aphyric type whereas pyroclastic deposits are classified as tuff breccia, lapilli tuff, tuffand ignimbrite. Fractured crystal and brecciated lithic fragments in tuff; fiamme and eutaxitic texture of ignimbrite suggest for subaerial eruption. The felsic meta-volcanics are rhyolitic to dacitic in composition and interbedded with tuffaceous phyllite, phyllite and quartzite.Keywords
Felsic Volcanics, Ignimbrite, Lava Flow, Tuff, Shillong Group, Subaerial.Full Text
References
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