Esker formation and glacier dynamics in eastern Skane and adjacent areas, southern Sweden

Abstract

Eskers were investigated in an area with overall terrestrial deglaciation ‐ the eastern part of the province of Skåne and adjacent areas in southern Sweden. On the basis of the proposed model of esker formation, the dynamics of the receding Weichselian Ice Sheet are discussed. The deglaciation was characterized by the gradual retreat of an active ice sheet, bordered by a zone of thin, stagnant ice. For the most part, the ice sheet was probably at the pressure melting point in a marginal zone, where it was penetrated by surface meltwater which constituted most of the subglacially flowing meltwater. The esker sediments, consisting of glaciofluvially reworked basal debris and basal till, accumulated progressively in an up‐glacier direction. Deposition took place close to the live ice boundary in the zone with stagnant ice that fringed the receding ice sheet. The time‐transgressive formation of the eskers is reflected by repeated sediment sequences (morphosequences), i.e. sedimentary units composed of ridges that merge into extended hummocky deposits in a down‐glacier direction. They represent the momentary deposition of stratified drift in the proximal portion of the zone with stagnant ice.

Glacial meltwater landforms of central British Columbia

“…Eskers are curvi-linear landforms created by the deposition of glaciofluvial sediments carried in subglacial streams (Hebrand and Åmark, 1989;Mäkinen, 2003). The mor- Figure 1 for location).…”

“…Along their length, eskers can form sequences of ridges and beads or ridges leading to a fan (Gorrell and Shaw, 1991). Because eskers are commonly assumed to have formed close to the ice margin in a direction parallel to the ice surface slope (Hebrand and Åmark, 1989;Mäkinen, 2003) and perpendicular to the ice margin, they are, therefore, good proxies for successive ice marginal positions. Eskers have for example been used for the reconstructions of ice retreat patterns in Scandinavia (Kleman et al, 1997;2006), northeastern Labrador-Quebec, Canada (Clark et al, 2000;Jansson et al, 2002), Ireland (Greenwood and Clark, 2009a; and Great Britain (Clark et al, in press).…”

Thermal conditions at the bed of the Laurentide ice sheet in Maine during deglaciation: implications for esker formation

“…Donner 1965; Banerjee and McDonald, 1975;Hebrand and Å mark, 1989;Ashley and others, 1991;Bolduc, 1992, p. 115). It is commonly inferred that the segments are built near the distal ends of subglacial drainage systems, and that successive segments form as the ice margin retreats.…”

Interlobate esker architecture and related hydrogeological features derived from a combination of high-resolution reflection seismics and refraction tomography, Virttaankangas, southwest Finland

“…Eskers, defined as stratified sediments of gravel and sand deposited by glacial melt-water streams (Banerjee and McDonald 1975;Shreve 1985;Hebrand and Åmark 1989;Gorrell and Shaw 1991;Warren and Ashley 1994;Huddart et al 1999;Brennand 2000), are hydrogeological settings of great significance in areas that have undergone glaciation such as in Finland, Sweden, the British Isles, USA and Canada. They are remarkable aquifers that are often used also for construction aggregates, thus an accurate understanding and subsurface delineation of the large-scale structures as well as hydrogeological units within these precious groundwater reservoirs is essential for their environmental and economic usage (Boucher et al 2015;Nadeau et al 2015).…”