Seafloor kettle holes in Orleans Trough, Bransfield Basin, Antarctic Peninsula

Abstract

Melting out of ice blocks or larger ice masses that have been buried or partially buried by glacifluvial sediments can leave a characteristic subaerial landscape of meso-scale depressions or kettle holes, known as kettle topography (Benn & Evans 2010). Kettle topography on proglacial outwash plains, or sandurs, results from the release of glacial outburst floodwaters that transport icebergs onto sandurs where they are buried and later melt out to form hollows. Such features are especially well known from Iceland (e.g. Fay 2002; Russell & Knudsen 2002). In plan view, kettle-hole depressions tend to be roughly circular where individual icebergs have melted out, or irregular in shape where multiple ice blocks have been deposited together. Depth of burial and the amount of sediment in the block also determine the final shape of depressions, which usually occur with raised rims (Burr et al. 2009; Benn & Evans 2010). Although kettle holes have been described extensively in terrestrial glacial landscapes, few have been identified in submarine environments (e.g. Bennett et al. 2009). Here we present a high-resolution bathymetric dataset from central Bransfield Basin, northern …