Wenkchemna Glacier: ablation complex and rock glacier in the Canadian Rocky Mountains

Abstract

The characteristics and behavior of the Wenkchemna Glacier in the Valley of the Ten Peaks of the Canadian Rocky Mountains are described. Early descriptions, old photographs, tree-rings, an annual sequence of photos since 1965, and field observations provide a data base. The Wenkchemna Glacier combines characteristics of ice-cored rock glaciers, ablation complexes, and glaciers, supporting the concept of a transition between these features. It is the product of a unique geomorphic–climatic system where a large mountain wall of northerly exposure produces a glacial micro–climate, a freeze–thaw weathering environment, a high rockfall frequency, and copious avalanche activity that led, in turn, to a thin, active mass of glacier ice that is preserved by a cover of rock debris. The behavior of the Wenkchemna Glacier has lagged behind that of surrounding glaciers by at least 70 years. Stagnation and differential ablation are the primary processes of glacier wastage. The landforms produced by the Wenkchemna Glacier include rock glacier features, such as arcuate ridges of debris, as well as hummocky ablation moraines typical of glacier stagnation.