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

J. Daneshian ¹, S. Sarkar ², V. Sharma ³

Affiliations
1 Department of Geology, Teacher Training University, No-49 Mofatteh Ave, Tehran, IR
2 Birbal Sahni Institute of Palaeobotany, 53 University Road, Lucknow - 226 007, IN
3 Department of Geology, University of Delhi, Delhi -110 007, IN

Abstract

A nch palynofloral assemblage has been recorded for the first time from a stratigraphc section of the Inglis Formation at Inglis Island, Andarnan Sea, India Forty-six genera and fifty eight species belonging to differen botanical groups viz , dinoflagellate cysts, fungal remains, ptendophytic spores, and gymnospermous and angiospermous pollen have been recognized Geological ranges of some stratigraphically important palynotaxa suggest late Early Mioceneearly Middle Miocene age to the assemblage The recorded palynofloral assemblage is also closely comparable to that recorded horn late Early Miocene-Early Middle Miocene sediments of South Indla The palynoflora has been compared with the modem equivalents and it indicates a warm humid climate with high degree of rainfall during the deposition of the sequence In the area of investigation.

Keywords

Palynoflora, Late Early Miocene-Early Middle Miocene, Palaeoecology, Inglis Island, Andaman Sea

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V. Sharma ¹, J. Daneshian ¹, L. Bhagyapati Devi ¹

Affiliations
1 Department of Geology, University of Delhi, Delhi - 110 007, IN

Abstract

Two radiolanan assemblages are distinguished in the Calocydetta (C) costata Zone of Early to Middle Miocene from a stratigraphic section of Inghs Island, Andaman Sea Fluctuations in percent abundance of cooler and warmer water taxa in the section indicate changing water mass conditions Water mass fluctuations in the form of cooling and warming of surface water have also been identified in the same stratigraphic interval from various tropical Indian Ocean DSDP and ODP sites by other investigators using oxygen isotope data.

Keywords

Radiolana, Miocene, Andaman Sea, Inghs Island, Andaman-Nicobar.

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V. Sharma ¹, J. Daneshian ¹

Affiliations
1 Department of Geology, University of Delhi, Delhi - 110 007, IN

Abstract

One hundred and thirty three radiolarian taxa from two sections, one each at Nicholson Island and John Lawrence Island, Andaman Sea are reported. The assemblage is referable to upper Calocycletta costata Zone to lower Dorcadospyris alata Zone (late Early Miocene to early Middle Miocene, about 16.9 Ma to 15.9 Ma). Stratigraphic ranges of some selected species are compared with those in the deep sea drilling sites in the tropical Indian Ocean.

Keywords

Radiolaria, Micropaleontology, Miocene, Andaman-Nicobar Islands, Indian Ocean.

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