Palaeomonsoon and palaeoproductivity records of 18O, 13C and CaCO3 variations in the northern Indian Ocean sediments

18O and 13C of G. sacculifer have been measured in five cores from the northern Indian Ocean. In addition, high resolution analysis (1 to 2 cm) was performed on one core (SK-20-185) for both 18O and 13C in five species of planktonic foraminifera. CaCO3 variation was measured in two cores. The result...

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Main Authors: A Sarkar, R Ramesh Y, S K Bhattacharya, N B Price
Other Authors: The Pennsylvania State University CiteSeerX Archives
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Language:English
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Online Access:http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.513.3420
http://www.ias.ac.in/jess/mar2000/E1301.pdf
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spelling ftciteseerx:oai:CiteSeerX.psu:10.1.1.513.3420 2023-05-15T18:00:55+02:00 Palaeomonsoon and palaeoproductivity records of 18O, 13C and CaCO3 variations in the northern Indian Ocean sediments A Sarkar R Ramesh Y S K Bhattacharya N B Price The Pennsylvania State University CiteSeerX Archives application/pdf http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.513.3420 http://www.ias.ac.in/jess/mar2000/E1301.pdf en eng http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.513.3420 http://www.ias.ac.in/jess/mar2000/E1301.pdf Metadata may be used without restrictions as long as the oai identifier remains attached to it. http://www.ias.ac.in/jess/mar2000/E1301.pdf text ftciteseerx 2016-01-08T09:45:16Z 18O and 13C of G. sacculifer have been measured in five cores from the northern Indian Ocean. In addition, high resolution analysis (1 to 2 cm) was performed on one core (SK-20-185) for both 18O and 13C in five species of planktonic foraminifera. CaCO3 variation was measured in two cores. The results, presented here, show that the summer monsoon was weaker during 18 ka and was stronger during 9 ka, relative to modern conditions; 13C variations are consistent with independent evidence that shows that during the last glacial maximum (LGM; 18 ka) the upwelling was reduced while during 9 ka it was vigorous; calculation of CaCO3 flux shows that the LGM was characterized by low biogenic productivity in the Arabian Sea while during the Holocene productivity increased by 65%, as a direct consequence of the changes in upwelling. Similar changes (of lesser magnitude) are also seen in the equatorial Indian Ocean. The amount of terrigenous input into the Arabian Sea doubled during LGM possibly due to the higher erosion rate along the west coast. 18O values indicate that the Arabian Sea was saltier by 1 to 2 % during LGM. The northern part was dominated by evaporation while in the equatorial part there was an increased precipitation. 1. Text Planktonic foraminifera Unknown Indian
institution Open Polar
collection Unknown
op_collection_id ftciteseerx
language English
description 18O and 13C of G. sacculifer have been measured in five cores from the northern Indian Ocean. In addition, high resolution analysis (1 to 2 cm) was performed on one core (SK-20-185) for both 18O and 13C in five species of planktonic foraminifera. CaCO3 variation was measured in two cores. The results, presented here, show that the summer monsoon was weaker during 18 ka and was stronger during 9 ka, relative to modern conditions; 13C variations are consistent with independent evidence that shows that during the last glacial maximum (LGM; 18 ka) the upwelling was reduced while during 9 ka it was vigorous; calculation of CaCO3 flux shows that the LGM was characterized by low biogenic productivity in the Arabian Sea while during the Holocene productivity increased by 65%, as a direct consequence of the changes in upwelling. Similar changes (of lesser magnitude) are also seen in the equatorial Indian Ocean. The amount of terrigenous input into the Arabian Sea doubled during LGM possibly due to the higher erosion rate along the west coast. 18O values indicate that the Arabian Sea was saltier by 1 to 2 % during LGM. The northern part was dominated by evaporation while in the equatorial part there was an increased precipitation. 1.
author2 The Pennsylvania State University CiteSeerX Archives
format Text
author A Sarkar
R Ramesh Y
S K Bhattacharya
N B Price
spellingShingle A Sarkar
R Ramesh Y
S K Bhattacharya
N B Price
Palaeomonsoon and palaeoproductivity records of 18O, 13C and CaCO3 variations in the northern Indian Ocean sediments
author_facet A Sarkar
R Ramesh Y
S K Bhattacharya
N B Price
author_sort A Sarkar
title Palaeomonsoon and palaeoproductivity records of 18O, 13C and CaCO3 variations in the northern Indian Ocean sediments
title_short Palaeomonsoon and palaeoproductivity records of 18O, 13C and CaCO3 variations in the northern Indian Ocean sediments
title_full Palaeomonsoon and palaeoproductivity records of 18O, 13C and CaCO3 variations in the northern Indian Ocean sediments
title_fullStr Palaeomonsoon and palaeoproductivity records of 18O, 13C and CaCO3 variations in the northern Indian Ocean sediments
title_full_unstemmed Palaeomonsoon and palaeoproductivity records of 18O, 13C and CaCO3 variations in the northern Indian Ocean sediments
title_sort palaeomonsoon and palaeoproductivity records of 18o, 13c and caco3 variations in the northern indian ocean sediments
url http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.513.3420
http://www.ias.ac.in/jess/mar2000/E1301.pdf
geographic Indian
geographic_facet Indian
genre Planktonic foraminifera
genre_facet Planktonic foraminifera
op_source http://www.ias.ac.in/jess/mar2000/E1301.pdf
op_relation http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.513.3420
http://www.ias.ac.in/jess/mar2000/E1301.pdf
op_rights Metadata may be used without restrictions as long as the oai identifier remains attached to it.
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