Paleotemperature History of the Cenozoic and the Initiation of Antarctic Glaciation: Oxygen and Carbon Isotope Analyses in DSDP Sites 277, 279 and 281

An oxygen and carbon isotopic history based on analyses of benthonic and planktonic foraminifera in three overlapping subantarctic sections is presented for the last 55 m.y. with a sampling interval ofless than 1 m.y. Surface temperature at Site 277, on the Campbell Plateau, was about 19C in the early Eocene, about 13C in the middle Eocene, about 11C in the late Eocene, and about 7C in the Oligocene. Declines in temperature appear to have been rather rapid and are separated by episodes of relative temperature stability. Bottom temperature at Site 277 was about 1C below surface temperature in the Paleocene and about 2C below surface temperature in the Oligocene.