Accession Number : ADP004802

Title :   A Deep Ice Core Drill System,

Corporate Author : COPENHAGEN UNIV (DENMARK) GEOPHYSICAL ISOTOPE LAB*

Personal Author(s) : Gundestrup,N. S. ; Johnsen,S. J. ; Reeh,N.

Report Date : DEC 1984

Pagination or Media Count : 13

Abstract : This report describes the ice core drill system used to core to bedrock at a depth of 2037.63 m near Dye-3 in South Greenland (65 deg 11 N 43 deg 49'W h = 2490m). The drill is designed to provide good core quality and to be easy to maintain in the field. It is a probe type system, with the drill suspended on a 6.4 mm cable. The drill consists of two parts. An antitorque section prevents rotation of the upper part, containing the motors and the electronics. During drilling, the ice chips, produced by the cutters, are sucked into the lower, rotating part of the drill. The chips are transported inside the drill to the surface, where the drill is clamped to a 6 m tower and tilted to a horizontal position for easy core removal and drill cleaning. The cutters work like a plane, which reduces the cutting power and provides stable penetration, essentially independent of the load on the cutters. The drill is powered by a rechargeable battery pack, and is controlled by a microprocessor in the drill. The length and weight of the drill are 11.5 m and 180 kg, respectively.

Descriptors :   *DRILLING MACHINES, *ICE, CORE SAMPLING, CORES, RECOVERY, DRILLS, CUTTING TOOLS, PROBES, DEEP DEPTH, GREENLAND, DENMARK

Distribution Statement : APPROVED FOR PUBLIC RELEASE