Cenozoic environmental changes along the East Antarctic continental margin inferred from regional seismic stratigraphy

Abstract

We interpret ~40 000 km of multichannel seismic reflection lines collected by the Russian Antarctic Expedition along the East Antarctic continental margin between 32 o E and 115 o E, and present a revised seismic stratigraphic model for depositional paleoenvironments of the region. Variations in acoustic facies characteristics observed across major seismic horizons are correlated with paleoenvironmental changes deciphered from Antarctic drilling data and deep-sea "proxy" records. Our results, as well as other studies, indicate that the East Antarctic margin was glaciated at different times. Glacial ice first reached the western Wilkes Land margin in the Middle Eocene and then advanced onto most parts of the East Antarctic continental shelf during the earliest Oligocene. During the Neogene, bottom currents deposited a variety of drift deposits along the margin.