PLEISTOCENE BENTHIC FORAMINIFERA AND DEEP-SEA ENVIRONMENTS AT NORTHERN INDIAN-OCEAN DSDP SITE 219

The evolution of Pleistocene deep-sea environments at Northern Indian Ocean DSDP Site 219 has been evaluated, using the quantitative analyses of deep-sea benthic foraminiferal fauna. The Pleistocene assemblages are dominated by Uvigerina proboscidea which shows remarkable frequency changes. The relative abundances of characteristic benthic foraminifera, and patterns of Species Diversity and Equitability have enabled identification of four events (C1-C4) of major faunal turnovers. These events have been inferred to represent intervals of fundamental changes in atmospheric-oceanic circulation, most likely the cooling and intensification of bottom-waters due to major increase in polar ice volume.