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H. N. Sinha ¹, S. S. Srivastava ², James Peters ³

Affiliations
1 Department of Geology, Vinoba Bhave University, Hazaribagh - 825 301, IN
2 Department of Earth Sciences, Indian Institute of Technology, Roorkee - 247 667, IN
3 KDMIPE, Geology Division, ONGC, Dehra Dun-248 195, IN

Abstract

The present study is an interdisciplinary approach to put forward a precise picture of Ordovician-Silurian acritarcha and other associated microfossil distribution in the Lower Palaeozoic Tethyan sequence of the Garhwal Himalaya, lndia For the purpose, sedimentological data, macrofauna and microflora from the Shiala and Yong Formations have been considered to constrain the environmental distribution of the microfossils It has been found that chitinozo and melanosclerites as well as acritarcha of Garhwal Tethys Himalaya have a wide range of adaptation The acritarcha bloomed during cool marine condition whereas chitinozoa and melanosclerites preferred mainly In warm-water condition of blooming The Shlala Formation was deposited under cool-water conditions In a shallow pulsating basin with a rapid variations In the depositonal environment and frequent sea-level changes This formation has been affected by the fluvial influx intermittently and possibly there was a sea-level drawdown at Ordovician-Silurian boundary An attempt has been made to correlate this phenomenon with a possible Late Ordovician glacioeustatic event and it is found that the Hirnantian glaciation was probably not situated in the Himalayan region The Yong Formation was deposited mainly in a shallow subtidal setting in a tranquil and low energy ancient warm-water mass.

Keywords

Microfossil flora and fauna, Acntarcha, Palaeoenvironment, Ordovician-Silurian, tethys Hlmalaya, Garhwal, Uttaranchal.

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K. Anbarasu , B. N. Tiwari ¹, H. N. Sinha

Affiliations
1 Wadia Institute of Himalayan Geology, 33 General Mahadeo Singh Road, Dehra Dun - 248 001, IN

Abstract

No Abstract.

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H. N. Sinha ¹, P. K. Mishra ²

Affiliations
1 Department of Geology, Vinoba Bhave University, Hazaribag-825 301, IN
2 Department of Botany, Vinoba Bhave University, Hazaribag-825 301, IN

Abstract

Well preserved, though rare occurrence of Chlorophyceae algae of genus Prismocorollina sp in one of the maroon coloured silty shale microfacies from the Thango Formation reveals that the deposition sediment took place in a shallow marine in adequately oxygenated, Warm-and climatic condition during the Early Ordovician time In the Tidong valley, Kinnaur Tethyan Himalaya.

Keywords

Prismocoroelina Sp , Thango Formation, Early Ordovician, Kinnaur Tethyan Himalaya, Himachal Pradesh.

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