An Investigation of Core Drilling in Perennially Frozen Gravels and Rock

• Main Author: Lange,G. Robert
• Other Authors: COLD REGIONS RESEARCH AND ENGINEERING LAB HANOVER N H
• Format: Text
• Language: English
• Published: 1973
• Subjects: Snow; Ice and Permafrost; Civil Engineering; *Foundations(Structures); *Permafrost; *Boreholes; Core sampling; Drilling machines; Drills; Rock drilling; Foundations(Structures); Alaska; Ice; permafrost
• Online Access: http://www.dtic.mil/docs/citations/AD0772705; http://oai.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=AD0772705

The problems of obtaining frozen samples by core drilling of perennially frozen gravel and rock were investigated. Most of the core drilling was carried out in ice-bonded, well-graded alluvial gravel with the ground temperature near its freezing point. Both chilled compressed air and oil-based liquids were used as drilling fluids. The details of both successful and unsuccessful coring attempts are reported and related to descriptions and photographs of samples of a wide range of quality. Drilling variables such as weight on the bit, rotational velocity, rate of penetration, fluid temperatures, viscosities, flow rates and pressures and mechanical details of the diamond bits are reported. (Modified author abstract)