Journal of Geological Society of India (Online archive from Vol 1 to Vol 78)

A. N. Shah ¹, P. P. Patel ²

Affiliations
1 Indian Co-Operation Mission, Kathmandu, NP
2 Department of Geology. M. S. University of Baroda, Baroda 2, IN

Abstract

The granitic gneisses of Lansdowne area form a part of the Amri unit of Garhwal nappe, formed before the main Himalayan orogeny. Field and petrological observations indicate that they have been thrust along with the crystalline rocks of Amri unit and there is no separate thrust contact between them. Chemical analysis and Petrography of the samples of gneisses from the margin to the centre show a progressive increase in feldspar-content which suggests a metasomatic origin for these granitic gneisses.

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Ravindra Kumar ¹, A. N. Shah ¹, D. K. Bingham ¹

Affiliations
1 Department of Geology, Tribhuvan University, Kathmandu, NP

Abstract

An angular unconformity between fossiliferous Early-Middle Palaeozoic and Precambrian rocks, yet not known in the Himalaya, has been discovered in Central Nepal. The underlying Precambrian rocks show at least one additional distinct foliation and lineation than the overlying Early-Middle Palaeozoic rocks. This deformation is attributed to a Precambrian tectonic phase.

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D. M. Shringarpure ¹, A. N. Shah ¹

Affiliations
1 Department of Geology, M. S. University of Baroda, 390002, IN

Abstract

Some well-preserved star shaped, cylindrical, curved, horizontal and vertical burrow like structures in the green and purple coloured shales of the Subathu roch of Nilkanth are described. Most of these structures are mud-lined, smooth surfaced and have relatively low densities and localised occurrence. These structures recognised as trace fossil burrows of Thalassinoides, Palacophycus and Planolites. Possible Palaeoenvironments in which the trace making communities lived are indicated.

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