The formation of glacial flutes: Assessment of models with evidence from Lyngsdalen, North Norway
1992; Elsevier BV; Volume: 11; Issue: 7-8 Linguagem: Inglês
10.1016/0277-3791(92)90079-n
ISSN1873-457X
AutoresJohn E. Gordon, W. Brian Whalley, Anne F. Gellatly, Diana M. Vere,
Tópico(s)Climate change and permafrost
ResumoFlutes are a distinctive type of glacial landform and comprise closely-spaced, streamlined ridges and furrows usually developed on till surfaces and aligned parallel to ice movement direction. Several models proposed to explain their formation involve, at least in part, post-depositional deformation or transfer of subglacial sediments; others involve primary deposition or erosion. The flutes on several glacier forelands in the mountains of the southern Lyngen peninsula in North Norway are associated with glaciers with cold-based margins. To explain the formation of the flutes three main sets of variables are investigated: 1, the landforms and their shapes, dimensions and field relationships; 2, the physical properties of the materials comprising the flutes; and 3, the glacier properties, and in particular, the basal thermal regime and ice-debris relationships at the glacier margin. Existing models of flute formation which involve post-depositional deformation or transfer of subglacial sediments do not explain satisfactorily several aspects of the flutes found in Lyngen. Instead, a model is proposed in which the flutes are primary features formed by deformation of the basal ice layer around subglacial boulders or other obstacles.
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