A Preliminary Scanning Electron Microscope Study of Quartz Grains from a Dirt Band in the Tuto Ice Tunnel, Northwest Greenland

Abstract

Quartz sand grains, 120 to 500 μm diameter obtained from a dirt band in the Tuto ice tunnel were examined with a scanning electron microscope. A single population of slightly weathered, angular to subangular grains was found. The grains were probably released from parent rock by subaerial weathering. Some surface deposition of silica was found although this was generally light. No edge attrition, suggestive of subglacial or englacial shearing or grinding, was found. This suggests passive, basal freeze-on processes for the incorporation of subglacial debris into the dirt bands.