Deep Rotary Core Drilling in Ice

Rotary drilling equipment was modified and used to obtain cores form glaciers in Northwest Greenland, Byrd Station and Little America V, Antarctica. Using cold compressed air, specially designed bits and other modifications, cores were obtained to 1345 feet in Greenland, 1000 feet at Byrd Station and Ice Shelf was penetrated to a depth of 840 feet at Little America V. In all locations cracks in the core appeared with increasing frequency due to the sudden release of the overburden lead when the core was cut in the air-filled hole. Special equipment and techniques developed dealt with the problem with some success. It is suggested that better cores and greater depths may be obtained by using diesel fuel as the circulating medium. A wireline system instead of drill pipe is suggested for coring to 10,000 foot depths in polar glaciers.