V. Zagorodnov et al., Antifreeze thermal ice core drilling: an effective approach to the acquisition of ice cores, COLD REG SC, 28(3), 1998, pp. 189-202
Antifreeze thermal electric drills have a long history of ice drilling in t
emperate, subpolar and polar glaciers. Shallow, intermediate and deep ice c
ores have been obtained in Arctic, Antarctic and on high elevation glaciers
. Many merits and drawbacks of antifreeze thermal technology have been disc
overed over the past 25 years. A modified version of the antifreeze thermal
electric ice coring drill has recently been developed and tested in the la
boratory and in the field for use with an ethanol-water solution. This ther
mal drill reduces thermal stresses in an ice core by a factor of 5 compared
to that of conventional thermal drills and produces good quality ice core.
The new drill was used to obtain a 315-m ice core in Franz Josef Land in t
he high Russian Arctic. It is viewed as a practical and cost-effective alte
rnative to the electromechanical fluid-operated drills for intermediate dep
th ice coring in subpolar sand remote high elevation glaciers. Alternating
an electromechanical drill with the antifreeze thermal drill in the bottom
of Antarctic Ice Sheet may provide a cost effective way for acquiring good
quality multiple ice cores. This approach would also reduce possible enviro
nmental impact on subglacial lakes and allow making multiple access holes.
Previous results of ice coring with an ethanol-water solution are summarize
d below. Then, the new thermal drilling equipment along with the results of
laboratory and field tests are presented. All aspects of the antifreeze th
ermal electric drilling process are discussed along with prospects for furt
her improvements. (C) 1998 Elsevier Science B.V. All rights reserved.