A Battery Powered, Instrumented Deep Ice Core Drill for Liquid Filled Holes
- C.C. Langway Jr.,
- H. Oeschger and
- W. Dansgaard
Published Online: 18 MAR 2013
Copyright 1985 by the American Geophysical Union.
Greenland Ice Core: Geophysics, Geochemistry, and the Environment
How to Cite
Gundestrup, N. S. and Johnsen, S. J. (1985) A Battery Powered, Instrumented Deep Ice Core Drill for Liquid Filled Holes, in Greenland Ice Core: Geophysics, Geochemistry, and the Environment (eds C.C. Langway, H. Oeschger and W. Dansgaard), American Geophysical Union, Washington, D. C.. doi: 10.1029/GM033p0019
- Published Online: 18 MAR 2013
- Published Print: 1 JAN 1985
Print ISBN: 9780875900575
Online ISBN: 9781118664155
- Ice sheets—Greenland—Addresses, essays, lectures;
- Greenland Ice Sheet Program
The ice core drill used at Dye 3 for coring to bedrock at 2038-m depth is described. The main design criteria was low cost and weight, and easy maintenance in the field. The drill is divided into two main parts. The upper section consists of the antitorque section that prevents rotation of the upper part, the motors and the electronics. During drilling, the ice chips produced by the cutters are sucked into the lower, rotating part of the drill and transported with the drill to the surface, where the drill is clamped to a 6 m tower and tilted to horizontal position for easy core removal and drill cleaning. The cutters work like a plane, with an aggressive cutting angle that 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, charged through the 6.4-mm cable. A microcomputer built into the drill controls 7 functions (battery charge and temperature, motor rotation speed and direction, etc.) at the same time that it measures 32 parameters. All this information is transmitted to a data terminal at the surface. The length of the drill is 11.5 m and its weight is 180 kg. The tower and the winch, including an electro-hydraulic pumpstation and 2500 m of cable, weigh 900 kg total. Core length is about 2.2 m per run, and the weekly core retrieval is 120 m of 10 cm diameter core at the 2000 m depth. The core recovery is better than 99.9%. Close to bedrock the hole deviates 6 degrees from the vertical, and the temperature is −13°C (−20°C at surface).