Initiation of Northern Hemisphere glaciation and strengthening of the Northeast Indian monsoon; Ocean Drilling Program Site 758, eastern equatorial Indian Ocean

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doi: 10.1130/0091-7613(2003)031<0047:IONHGA>2.0.CO;2
Author(s): Gupta, Anil K.; Thomas, Ellen
Author Affiliation(s): Primary:
Indian Institute of Technology, Department of Geology and Geophysics, Kharagpur, India
Wesleyan University, United States
Volume Title: Geology (Boulder)
Source: Geology (Boulder), 31(1), p.47-50. Publisher: Geological Society of America (GSA), Boulder, CO, United States. ISSN: 0091-7613 CODEN: GLGYBA
Note: In English. With GSA Data Repository Item 2003004. 36 refs.; illus., incl. 1 table, sketch map
Summary: The Indian monsoon system, as recorded by ocean-floor biota (benthic foraminifera) at Ocean Drilling Program Site 758 in the eastern equatorial Indian Ocean, has varied dramatically over the past 5.5 m.y., long after the onset of the monsoons at 10-8 Ma. Benthic foraminifera that thrive with high productivity year-round were common before the formation of Northern Hemisphere continental ice sheets ca. 3.1-2.5 Ma, indicating that the summer (southwest) monsoon had high intensity and long seasonal duration. Ca. 2.8 Ma benthic faunas became dominated by taxa that flourish with a seasonally strongly fluctuating food supply, indicating that the northeast (winter) monsoon, during which primary productivity is relatively low, increased in duration and strength to form a system similar to that of today. The change occurred coeval with the initiation of the Northern Hemisphere glaciation, documenting a close link between the development of the Indian monsoon and Northern Hemisphere glaciation.
Year of Publication: 2003
Research Program: ODP Ocean Drilling Program
Key Words: 12 Stratigraphy, Historical Geology and Paleoecology; Benthic taxa; Biofacies; Cenozoic; East Indian Ocean; Equatorial region; Factor analysis; Foraminifera; Glaciation; Indian Ocean; Invertebrata; Leg 121; Marine environment; Microfossils; Monsoons; Neogene; Northern Hemisphere; ODP Site 758; Ocean Drilling Program; Paleo-oceanography; Paleocirculation; Paleoclimatology; Paleoecology; Pliocene; Productivity; Protista; Seasonal variations; Statistical analysis; Tertiary
Coordinates: N052302 N052303 E0902141 E0902140
Record ID: 2003014304
Copyright Information: GeoRef, Copyright 2017 American Geosciences Institute. Reference includes data supplied by the Geological Society of America, Boulder, CO, United States