CGRG Bibliography of Canadian Geomorphology
Search Results
Author : Elconin, R.F.; LaChapelle, E.R.
Date : 1997
Title : Flow and internal structure of a rock glacier
Publication : Journal of Glaciology
Issue : 43(144):
Page(s) : 238-244
Abstract
Exposure of a full transverse cross-section of the terminus of Fireweed rock glacier, Wrangell Mountains, Alaska, revealed a thin layer of unconsolidated debris mantling a consolidated melange of ice and rock. The main rock glacier is fed by three tributaries; at the terminus, contacts between the three are sharply defined. Ice content is >50% by volume. Bubble foliation and crystal morphologies of the ice matrix are similar to those reported from glacier ice. Folded ice-rich strata and lenses, foliation planes, and the long-intermediate axial planes of tabular-shaped englacial clasts dip steeply toward the center line of the rock glacier: The planar structures generally parallel the steep walls of the gorge containing the trunk stream. These steeply dipping, longitudinal structures appear to result from transverse compression where the tributaries converge and the trunk stream narrows down-valley. Bergschrund-like and moulin-like features at the heads of the middle and west tributaries, respectively, exposed admired ice and rock similar to that of the terminus but lacking the well-developed flow texture. Talus from the unstable cirque headwall and polygenetic ice both accumulate at the base of the headwall and nourish the tributary rock glaciers.
Bibliography of Canadian Geomorphology