Natural cairns on rock glaciers as an indication of a solid ice core

Abstract

Humlum, Ole: Natural cairns on rock glaciers as an indication of a solid ice core. Geografisk Tidsskrift 88:78–82. Copenhagen. 1988.

A special surface feature taking the form of natural cairns is observed on rock glaciers in Disko, central West Greenland, known to possess a core of solid ice. These block accumulations are perceived as developed by the gradually outcropping of large en-glacial blocks from the ice core due to surface ablation, thereby lifting surface debris lying above. Below a line on the rock glacier where the surface debris layer equals or exceeds the depth of summer thaw, no more cairns are developed. Natural cairns as these on rock glaciers are suggested as a criterion for the existence of a solid ice core within the rock glacier, and the designation rock glacier cairn is proposed for them.

Keywords:

• Rock glacier
• Glacier-derived rock glacier
• West Greenland
• Disko