Proposed Programme

Surveys of the sea floor of McMurdo Sound and Granite Harbour have shown that sediment texture there is, in broad terms, bathymetrically controlled with mud in the basins, muddy sand on the slopes and sand on the shelves (Barrett et al. 1983). Foraminiferal studies also show some bathymetric control, though in this case the controlling factor is the carbonate compensation depth at 620 m offshore and 230 m in the harbours (Ward et al. 1987). The main purpose of this project is to document the relationship between sediment texture, micro-organisms (diatoms and foraminifera) and water depth from the shoreline to the 100 m contour along the Victoria Land coast. This areally limited zone has come to be of particular interest because studies of the MSSTS-1 drill core (Barrett 1986) show how variations in species diversity and sediment texture may be used to follow sea level changes in cored sequences. Changes to be expected are an increase in mud content and a decrease in mean size seaward due to declining wave power (cf. Jago & Barusseau 1981; Barrett 1986), an increase in species diversity (Webb et al. 1986) and in the case of diatoms an increase in benthic/planktic ratio (Harwood 1986). Data from the modern shoreline are needed for comparison with older shallow marine polar sequences like that cored in MSSTS-1.