New stable isotope records of sediment cores from the SE Arabian Sea - Inferences on the variations in monsoon regime during the late Quaternery
DRS at CSIR-National Institute of Oceanography
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Title |
New stable isotope records of sediment cores from the SE Arabian Sea - Inferences on the variations in monsoon regime during the late Quaternery
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Creator |
Thamban, M.
Rao, V.P. |
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Subject |
Indian monsoons
foraminifers Indian Ocean primary productivity |
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Description |
We reconstruct here the changes in regional hydrography related to the fluctuations in Indian monsoons during the late Quaternary based on the stable isotope composition of the foraminifers and organic matter in three sediment cores from the upper continental slope of western India. The planktic foraminiferal d18O contrast between the Last Glacial Maximum (LGM) and Holocene (Dd18O), after correcting for the global ‘ice effect’ is relatively high (0.8–1.0‰), suggesting notable changes in the sea surface conditions. This includes a moderate sea surface cooling (~ 2°C) and an enhanced evaporation (increasing salinity by ~ 2.5 p.s.u.) during the LGM and/or increased precipitation during the early Holocene. The diminished Dd18O value of benthic records (~ 1.0‰) appears to be a basin-wide phenomenon along the shallow depths of the upper continental slope and is related to the eustatic sea level fluctuations. Carbon isotope composition of the organic matter suggests that primary productivity was the main source of organic carbon along this margin throughout the late Quaternary.
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Date |
2006-08-26T15:34:09Z
2006-08-26T15:34:09Z 2001 |
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Type |
Journal Article
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Identifier |
Current Science, vol. 80(11), 1432-1436pp.
http://drs.nio.org/drs/handle/2264/269 |
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Language |
en
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Format |
120832 bytes
application/pdf |
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Publisher |
Indian Academy of Sciences
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