Radio-echo sounding at the Mittivakkat Gletscher, southeast Greenland

Profiles along sounding lines and maps are presented of the glacier surface, bottom topography, and ice thickness of Mittivakkat Gletscher. The maps are the result of the use of monopulse radio-echo sounding of ice thickness in about 450 points along profiles across the glacier. The position of most points was surveyed using a theodolith together with Electrooptic Distance Measurement. The Mittivakkat Gletscher consists of several accumulation basins which combine into a single ice tongue. There is a marked relief underneath the glacier, and it is possible to identify two major subglacial depressions, which probably strongly influence the subglacial drainage of water from the glacier. The bottom topography is reflected in the surface topography and in the position of crevassed areas. The following data were extracted: area: 17.6 km(2); volume: 2024 x 10(6) m(3); ice thickness, H-mean: 115 m; ice thickness, H-max: 245 m.