Quaternary climatic changes indicated by planktonic foraminifera of Northern Indian Ocean
The relative abundances of planktonic foraminifera, the changes in their coiling and the isotopic record from deep sea cores of some crucial sites in Northern Indian Ocean indicate climatic fluctuations for the past 3.0 million years (Late Pliocene to Pleistocene). The abundance of temperate forms l...
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ftindianacasci:oai:repository.ias.ac.in:77408 2023-05-15T18:00:34+02:00 Quaternary climatic changes indicated by planktonic foraminifera of Northern Indian Ocean Singh, A. D. Srinivasan, M. S. 1993-06-25 application/pdf http://repository.ias.ac.in/77408/ http://repository.ias.ac.in/77408/1/77408.pdf http://cs-test.ias.ac.in/cs/Downloads/article_28608.pdf unknown Current Science Association http://repository.ias.ac.in/77408/1/77408.pdf Singh, A. D. Srinivasan, M. S. (1993) Quaternary climatic changes indicated by planktonic foraminifera of Northern Indian Ocean Current Science, 64 (11-12). pp. 908-915. ISSN 0011-3891 QE Geology Article PeerReviewed 1993 ftindianacasci 2013-01-20T13:01:30Z The relative abundances of planktonic foraminifera, the changes in their coiling and the isotopic record from deep sea cores of some crucial sites in Northern Indian Ocean indicate climatic fluctuations for the past 3.0 million years (Late Pliocene to Pleistocene). The abundance of temperate forms like Globigerina spp, together with sporadic occurrence of a polar species Neogloboquadrina pachyderm. during specific time intervals suggest cooling episodes. Warmer intervals are marked by the dominance of tropical assemblages including Globigerinoides spp., Globorotalia s.l., Pulleniatina and Globoquadrina. On the basis of the planktonic foraminiferal frequency changes, four intervals of major climatic cooling have been recognized- one in the Late Pliocene (2-3 m.y.), three in the Pleistocene immediately above the Pliocene/Pleistocene boundary (1.6 m.y.), at 0.6 m.y., and during the late Pleistocene. Marked shift in coiling directions within Pulleniatina populations and Globorotalia s.l., is observed to coincide with the frequency changes. There was marked increase of δ 18 O values in oxygen isotopic record of foraminiferal tests around 2-3 m.y. (Late Pliocene) and within the Pleistocene. Major faunal turnover accompanied by changes in coiling synchronous with the isotopic shilts, suggest these faunal changes to be climatically induced. Article in Journal/Newspaper Planktonic foraminifera Indian Academy of Sciences: Publication of Fellows Indian |
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Open Polar |
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Indian Academy of Sciences: Publication of Fellows |
op_collection_id |
ftindianacasci |
language |
unknown |
topic |
QE Geology |
spellingShingle |
QE Geology Singh, A. D. Srinivasan, M. S. Quaternary climatic changes indicated by planktonic foraminifera of Northern Indian Ocean |
topic_facet |
QE Geology |
description |
The relative abundances of planktonic foraminifera, the changes in their coiling and the isotopic record from deep sea cores of some crucial sites in Northern Indian Ocean indicate climatic fluctuations for the past 3.0 million years (Late Pliocene to Pleistocene). The abundance of temperate forms like Globigerina spp, together with sporadic occurrence of a polar species Neogloboquadrina pachyderm. during specific time intervals suggest cooling episodes. Warmer intervals are marked by the dominance of tropical assemblages including Globigerinoides spp., Globorotalia s.l., Pulleniatina and Globoquadrina. On the basis of the planktonic foraminiferal frequency changes, four intervals of major climatic cooling have been recognized- one in the Late Pliocene (2-3 m.y.), three in the Pleistocene immediately above the Pliocene/Pleistocene boundary (1.6 m.y.), at 0.6 m.y., and during the late Pleistocene. Marked shift in coiling directions within Pulleniatina populations and Globorotalia s.l., is observed to coincide with the frequency changes. There was marked increase of δ 18 O values in oxygen isotopic record of foraminiferal tests around 2-3 m.y. (Late Pliocene) and within the Pleistocene. Major faunal turnover accompanied by changes in coiling synchronous with the isotopic shilts, suggest these faunal changes to be climatically induced. |
format |
Article in Journal/Newspaper |
author |
Singh, A. D. Srinivasan, M. S. |
author_facet |
Singh, A. D. Srinivasan, M. S. |
author_sort |
Singh, A. D. |
title |
Quaternary climatic changes indicated by planktonic foraminifera of Northern Indian Ocean |
title_short |
Quaternary climatic changes indicated by planktonic foraminifera of Northern Indian Ocean |
title_full |
Quaternary climatic changes indicated by planktonic foraminifera of Northern Indian Ocean |
title_fullStr |
Quaternary climatic changes indicated by planktonic foraminifera of Northern Indian Ocean |
title_full_unstemmed |
Quaternary climatic changes indicated by planktonic foraminifera of Northern Indian Ocean |
title_sort |
quaternary climatic changes indicated by planktonic foraminifera of northern indian ocean |
publisher |
Current Science Association |
publishDate |
1993 |
url |
http://repository.ias.ac.in/77408/ http://repository.ias.ac.in/77408/1/77408.pdf http://cs-test.ias.ac.in/cs/Downloads/article_28608.pdf |
geographic |
Indian |
geographic_facet |
Indian |
genre |
Planktonic foraminifera |
genre_facet |
Planktonic foraminifera |
op_relation |
http://repository.ias.ac.in/77408/1/77408.pdf Singh, A. D. Srinivasan, M. S. (1993) Quaternary climatic changes indicated by planktonic foraminifera of Northern Indian Ocean Current Science, 64 (11-12). pp. 908-915. ISSN 0011-3891 |
_version_ |
1766169717614051328 |