Rai, A. K. and Srinivasan, M. S. (2000): Deep sea benthic foraminiferal response to the Pliocene palaeoenvironments of the northern Indian Ocean

Leg/Site/Hole:
DSDP 23
DSDP 24
DSDP 23 219
DSDP 24 237
Identifier:
2001-047164
georefid

10.1016/S0016-6995(00)80159-X
doi

Creator:
Rai, A. K.
Allahabad University, Department of Earth & Planetary Sciences, Allahabad, India
author

Srinivasan, M. S.
Banaras Hindu University, Varanasi, India
author

Identification:
Deep sea benthic foraminiferal response to the Pliocene palaeoenvironments of the northern Indian Ocean
2000
Geobios
Universite Claude Bernard, Departement de Geologie, Lyon, France
33
3
301-308
The benthic foraminiferal contents of two DSDP sites 219 (Arabian Sea) and 237 (Mascarene Plateau) have been analysed in order to understand paleoceanographic changes in the northern Indian Ocean during Pliocene. Uvigerina proboscidea is the most dominant taxon with intervals of marked fluctuations in its abundance at both the sites reflecting relatively higher surface water productivity with changing magnitudes during Pliocene. Earliest Pliocene (c. 5.6 to 5.0 Ma) is the interval of distinct increase in the surface water productivity in response to more SW Indian Ocean monsoonal upwelling. The faunal assemblage during c. 5.0 to 4.0 Ma suggests relatively warm, oxygenated and more saline bottom waters and moderately low surface water productivity in the Arabian Sea region. This was also broadly the period of global warmth and higher eustatic sea level. The surface water productivity during c. 4.0 to 3.4 Ma at site 219 was moderately higher. However, site 237 is characterised by strong bottom currents and relatively lower surface productivity. Further, the latest Pliocene (c. 2.5 Ma onwards) is characterised by significantly higher surface water productivity induced by higher rates of SW Indian Ocean monsoonal upwelling which corresponds with the onset of major Northern Hemisphere glaciation. These paleoenvironmental changes are suggested to be mainly responsible for several last occurrences of benthic foraminiferal taxa near the Pliocene/Pleistocene transition.
English
Serial
Coverage:Geographic coordinates:
North:30.3000
West:47.3000East: 77.0000
South:-7.0500

Stratigraphy; Arabian Sea; benthic taxa; biostratigraphy; Buliminacea; Cenozoic; Chordata; Deep Sea Drilling Project; deep-sea environment; DSDP Site 219; DSDP Site 237; Eutheria; Foraminifera; Indian Ocean; Invertebrata; Leg 23; Leg 24; Mammalia; marine environment; Mascarene Plateau; microfossils; Neogene; northern Indian Ocean; paleo-oceanography; Pliocene; Proboscidea; productivity; Protista; Rotaliina; Tertiary; Tetrapoda; Theria; upper Tertiary; upwelling; Uvigerina; Uvigerinidae; Vertebrata;

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