Benthic foraminiferal faunal and isotopic changes as recorded in Holocene sediments of the northwest Indian Ocean
Historically, the Holocene has been considered an interval of relatively stable climate. However, recent studies from the northern Arabian Sea (Netherlands Indian Ocean Program 905) suggested high-amplitude climate shifts in the early and middle Holocene based on faunal and benthic isotopic proxy re...
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ftindianacasci:oai:repository.ias.ac.in:21928 2023-05-15T17:25:27+02:00 Benthic foraminiferal faunal and isotopic changes as recorded in Holocene sediments of the northwest Indian Ocean Gupta, Anil K. Das, Moumita Clemens, Steven C. Mukherjee, Baidehi 2008-05 http://repository.ias.ac.in/21928/ http://www.agu.org/pubs/crossref/2008/2007PA001546.shtml unknown American Geophysical Union Gupta, Anil K. Das, Moumita Clemens, Steven C. Mukherjee, Baidehi (2008) Benthic foraminiferal faunal and isotopic changes as recorded in Holocene sediments of the northwest Indian Ocean Paleoceanography, 23 (2). PA2214_1- PA2214_10. ISSN 0883-8305 QE Geology Article PeerReviewed 2008 ftindianacasci 2013-01-20T10:26:08Z Historically, the Holocene has been considered an interval of relatively stable climate. However, recent studies from the northern Arabian Sea (Netherlands Indian Ocean Program 905) suggested high-amplitude climate shifts in the early and middle Holocene based on faunal and benthic isotopic proxy records. We examined benthic foraminiferal faunal and stable isotopic data from Ocean Drilling Program (ODP) Site 723 and total organic carbon data from ODP Site 724, Oman Margin (808 and 593 m water depths, respectively). At Site 723 the mid-Holocene shift in δ 18 O values of infaunal benthic species Uvigerina peregrina (1.4‰) is 3 times larger than that of epifaunal benthic species Cibicides kullenbergi recorded at Site NIOP 905 off Somalia. However, none of the five other benthic species we measured at Hole 723A exhibits such a shift in δ 18 O. We speculate that the late Holocene δ 18 O decrease in U. peregrina represents species-specific changes in ecological habitat or food preference in response to changes in surface and deep ocean circulation. While the stable isotopic data do not appear to indicate a middle Holocene climatic shift, our total organic carbon and benthic faunal assemblage data do indicate that the early Holocene deep Arabian Sea was influenced by increased ventilation perhaps by North Atlantic Deep Water and/or Circumpolar Deep Water incursions into the Indian Ocean, leading to remineralization of organic matter and a relatively weak early Holocene oxygen minimum zone in the northwest Arabian Sea in spite of strong summer monsoon circulation. Article in Journal/Newspaper North Atlantic Deep Water North Atlantic Indian Academy of Sciences: Publication of Fellows Indian |
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Indian Academy of Sciences: Publication of Fellows |
op_collection_id |
ftindianacasci |
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topic |
QE Geology |
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QE Geology Gupta, Anil K. Das, Moumita Clemens, Steven C. Mukherjee, Baidehi Benthic foraminiferal faunal and isotopic changes as recorded in Holocene sediments of the northwest Indian Ocean |
topic_facet |
QE Geology |
description |
Historically, the Holocene has been considered an interval of relatively stable climate. However, recent studies from the northern Arabian Sea (Netherlands Indian Ocean Program 905) suggested high-amplitude climate shifts in the early and middle Holocene based on faunal and benthic isotopic proxy records. We examined benthic foraminiferal faunal and stable isotopic data from Ocean Drilling Program (ODP) Site 723 and total organic carbon data from ODP Site 724, Oman Margin (808 and 593 m water depths, respectively). At Site 723 the mid-Holocene shift in δ 18 O values of infaunal benthic species Uvigerina peregrina (1.4‰) is 3 times larger than that of epifaunal benthic species Cibicides kullenbergi recorded at Site NIOP 905 off Somalia. However, none of the five other benthic species we measured at Hole 723A exhibits such a shift in δ 18 O. We speculate that the late Holocene δ 18 O decrease in U. peregrina represents species-specific changes in ecological habitat or food preference in response to changes in surface and deep ocean circulation. While the stable isotopic data do not appear to indicate a middle Holocene climatic shift, our total organic carbon and benthic faunal assemblage data do indicate that the early Holocene deep Arabian Sea was influenced by increased ventilation perhaps by North Atlantic Deep Water and/or Circumpolar Deep Water incursions into the Indian Ocean, leading to remineralization of organic matter and a relatively weak early Holocene oxygen minimum zone in the northwest Arabian Sea in spite of strong summer monsoon circulation. |
format |
Article in Journal/Newspaper |
author |
Gupta, Anil K. Das, Moumita Clemens, Steven C. Mukherjee, Baidehi |
author_facet |
Gupta, Anil K. Das, Moumita Clemens, Steven C. Mukherjee, Baidehi |
author_sort |
Gupta, Anil K. |
title |
Benthic foraminiferal faunal and isotopic changes as recorded in Holocene sediments of the northwest Indian Ocean |
title_short |
Benthic foraminiferal faunal and isotopic changes as recorded in Holocene sediments of the northwest Indian Ocean |
title_full |
Benthic foraminiferal faunal and isotopic changes as recorded in Holocene sediments of the northwest Indian Ocean |
title_fullStr |
Benthic foraminiferal faunal and isotopic changes as recorded in Holocene sediments of the northwest Indian Ocean |
title_full_unstemmed |
Benthic foraminiferal faunal and isotopic changes as recorded in Holocene sediments of the northwest Indian Ocean |
title_sort |
benthic foraminiferal faunal and isotopic changes as recorded in holocene sediments of the northwest indian ocean |
publisher |
American Geophysical Union |
publishDate |
2008 |
url |
http://repository.ias.ac.in/21928/ http://www.agu.org/pubs/crossref/2008/2007PA001546.shtml |
geographic |
Indian |
geographic_facet |
Indian |
genre |
North Atlantic Deep Water North Atlantic |
genre_facet |
North Atlantic Deep Water North Atlantic |
op_relation |
Gupta, Anil K. Das, Moumita Clemens, Steven C. Mukherjee, Baidehi (2008) Benthic foraminiferal faunal and isotopic changes as recorded in Holocene sediments of the northwest Indian Ocean Paleoceanography, 23 (2). PA2214_1- PA2214_10. ISSN 0883-8305 |
_version_ |
1766116876920815616 |