Abstract:
The general character and geometry of sediments of the Ross Sea are known from extensive seismic surveys and stratigraphic drilling during Deep Sea Drilling Project (DSDP), leg 28 (sites 270-273), Cenozoic Investigations of the Ross Sea-1 (CIROS-1), and McMurdo Sound Sediment and Tectonic Studies (MSSTS-1), as well as numerous piston and gravity cores across the Ross Sea. In contrast, the stratigraphic record beneath the West Antarctic ice sheet and Ross Ice Shelf is very poorly known. Data available from beneath the Ross Ice Shelf and the West Antarctic ice sheet include limited seismic and other geophysical surveys and few sub-ice sediment samples that have been recovered from three sites in the southern Ross embayment, south of the Ross Ice Shelf barrier. Available sub-ice sediments from the Ross embayment include 53 short gravity cores recovered from beneath the southern Ross Ice Shelf Project (RISP), sediments recovered from Crary Ice Rise (CIR) during the 1987-1988 field season, and sediments recovered from beneath ice stream B in the vicinity of the Upstream B camp (UpB) during five field seasons on the ice sheet. All of the recovered West Antarctic interior sediments are glacial diamictons containing a mixture of particles, including diatom fossils derived from deposits of various Cenozoic ages.