17. PALEOTEMPERATURE HISTORY OF THE CENOZOIC AND THE INITIATION OF ANTARCTIC GLACIATION: OXYGEN AND CARBON ISOTOPE ANALYSES IN DSDP SITES

• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: Antarctic; Campbell Plateau; Antarc*; Planktonic foraminifera
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.598.3173; http://www.deepseadrilling.org/29/volume/dsdp29_17.pdf

An oxygen and carbon isotopic history based on analyses of ben-thonic and planktonic foraminifera in three overlapping subantarc-tic 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 19°C in the early Eocene, about 13°C in the mid-dle Eocene, about 11°C in the late Eocene, and about 7°C in the Oligocene. Declines in temperature appear to have been rather rapid and are separated by episodes of relative temperature stability. Bot-tom temperature at Site 277 was about 1°C below surface temperature in the Paleocene and about 2°C below surface temperature in the Oligocene. Site 279, on the Macquarie Ridge, records an early Miocene warming of over 2°C followed by a cooling and a second similar temperature rise in the middle Miocene. Bottom temperature at this