Antifreeze-Thermodrilling of Cores in Arctic Sheet Glaciers

In 1985-87 two Arctic sheet glaciers: Austfonna (Nordaustland) and Akademia Nauk (Severnaya Zemlya) ware cored with antifreeze electrothermal drill down their beds at 566.7 m and 761 m depth, respectively. The paper discusses the use of electrothermal drills for studies of the structure and hydrothermal regime of glaciers. It deals both with the equipment and results. The difficulties of drilling are also discussed, as well as ways to cope with them. Experiments on the reduction of bore hole inclination and on drilling of an additional bore hole to obtain an extra core from the bottom glacial stratum are described.