Depositional deglaciation forms as indicators of different glacial and glaciomarginal environments

Abstract

Kurimo, Heikki 1980 09 01: Depositional deglaciation forms as indicators of different glacial and glaciomarginal environments. Boreas, VOI. 9, pp. 179-191. O~I O . ISSN 0300-9483.The current system of nomenclature for landform elements associated with deglaciation is often insufficient and inappropriate to describe the total depositional environment. There is a manifold transition of the deposits in regard to morphology, orientation, arrangement, material, and material-related properties. A multidimensional scheme constructed to be maximally informative of the depositional environment is presented.

Geomorphic evidence for active and inactive phases of Late Devensian ice in north-central Ireland

“…4b), have been observed previously in similar glacial depositional settings and termed variously dclosed disintegration ridgesT (Gravenor and Kupsch, 1959), dring ridgesT (Kurimo, 1980), drim ridgesT (Eyles et al, 1999), dcircular morainesT (Ebert and Kleman, 2004) and dextrusion morainesT . Processes responsible for the formation of these landforms include meltout, sediment squeezing around dead ice blocks and high marginal groundwater pressure gradients (Mollard, 2000).…”

“…Ice-marginal landforms which show no preferential alignment of crest axes, or which do not have a distinctive outline shape, have been variously termed hummocky, dead-ice, uncontrolled and stagnation moraines (e.g., Hoppe, 1952;Gravenor and Kupsch, 1959;Kurimo, 1980;Benn, 1992;Bennett and Boulton, 1993). Use of these morphogenetic terms, however, has hindered interpretation of these landforms and the possible relationships to ice-marginal processes (Bennett and Boulton, 1993).…”

“…For example, the planform shape and alignment of end-(or ice-marginal) moraines have implications for the direction, speed and processes active at the retreating ice margin. Proglacial, ice-marginal moraines, however, may vary considerably in morphology from discrete, continuous ridges to wide, discontinuous areas of kettled, hummocky or stagnation topography (Kurimo, 1980;Sollid and Sør-bel, 1988;Benn, 1992;Hambrey et al, 1997;Mollard, 2000). Accurate interpretation of ice-marginal landforms is critical for several reasons: (1) reconstructing stages of ice advance and retreat; (2) reconstructing basal ice thermal and hydrological regimes (important for landform and sediment formation and preservation, especially near ice margins); (3) assessing ice-marginal activity (whether by active retreat or in situ ice stagnation); and (4) evaluating controls on ice advance and retreat patterns, including rapid climate change (Benn, 1992).…”

Ice‐lobe formation and function during the deglaciation in Finland and adjacent Soviet Karelia

“…Direct signs of active ice flow include striations, lodgement till fabric, streamlined forms, and, in some cases, also transverse subglacial forms (for transverse subglacial forms see e.g. Lundqvist 1%9; Aario 1977a; Kurimo 1980;Lucas & Howarth 1979). All the signs inherited directly from active-ice flow originate subglacially and are created either (1) during the advance period of the ice sheet or (2) during deglaciation under conditions when the ice is still moving but the net mass budget is negative.…”

Ribbed moraine formed by subglacial folding, thrust stacking and lee‐side cavity infill

“…Opposed to this stands the polygenetic view, suggested as early as 1980 by Kurimo and subsequently discussed by others, e.g. Lundqvist (1989), who argues that the very large size and shape variance and the large differences in spatial/topographical distribution of what is suggested to be ribbed moraine, combined with documented differences in internal architecture, composition and structures, point to a polygenetic origin.…”