9809273 Anderson This ESH project will attempt to obtain precise and accurate radiocarbon dates from Antarctic diatomaceous sediments. Preliminary work suggests that modern radiocarbon is adsorbed onto the material during preparation, resulting in artificially young ages. A variety of directions will be explored, including replacement of ambient CO2 in the gas vacuum line by other gases, and separation of the organic matrix from the enclosing silica. Successful application will permit the dating of known records of climate change hitherto undateable.