Debris from the basal ice of the Agassiz ice cap,Ellesmere Island,arctic Canada

This article describes the characteristics of debris obtained from the basal ice in a borehole in the Agassiz ice cap, Ellesmere Island, Northwest Territories by the Canadian Polar Continental Shelf Project in 1979. The debris appears to have been incorporated by basal freezing at a time when the base of the glacier upstream was near the pressure melting point and some 19°C warmer than at the present site. Such an occurrence may be explained by a different flow regime, by a thicker ice sheet, by the influence of irregular bedrock topography on basal ice conditions at some stage in the past, or by a combination of these factors.