PLIOCENE TO PLEISTOCENE ICE VOLUME CHANGES IN ANTARCTICA AS A FORCING FACTOR OF FAR-FIELD RECORDS

Traditionally, the correlation of ice-rafted debris (IRD) and fluctuations in the δ ¹⁸O record in the Northern Hemisphere (NH) were cited as evidence for a NH dominance of changes in global ice volume since ~ 3 Ma. However, interpretations of IRD records are complex, because sea level as an external control can force marine-grounded ice sheets and glaciers to disintegrate through the process of decoupling. As a result, both the δ ¹⁸O and the IRD signal of a NH deep-sea core can be forced by an ice sheet situated at considerable distance, i.e. in Antarctica. Studies of sedimentary records of high-latitude continental margins are, therefore, essential in reconstructions of the cryosphere and to groundtruth interpretations of climate and sea level proxies. In the past ten years, studies by the Ocean Drilling Program Leg 188, the Antarctic Geological Drilling Program, and the Integrated Ocean Drilling Program Exp. 318 have aimed to reconstruct the extent of the Antarctic ice sheets through studies of its continental margin. Recent studies indicate that the Antarctic ice sheets were dynamic until at least the middle Pliocene. This paper will provide an overview of Pliocene to Pleistocene sea level forcing from an Antarctic perspective.