Sediment distribution and sea-floor morphology of Storbanken: implications for the glacial history of the northern Barents Sea

• Published in: Canadian Journal of Earth Sciences
• Main Authors: Solheim, Anders, Milliman, John D., Elverhøi, Anders
• Format: Article in Journal/Newspaper
• Language: English
• Published: Canadian Science Publishing 1988
• Subjects: Barents Sea; Ice Sheet; Storbanken
• Online Access: http://dx.doi.org/10.1139/e88-053; http://www.nrcresearchpress.com/doi/pdf/10.1139/e88-053

Acoustical (sparker, 3.5 kHz, and side-scan sonar) and sedimentological data from a local study on Storbanken in the northern Barents Sea support the concept of a late Weichselian ice sheet covering most of the Barents Sea. During a major halt in the retreat of the ice sheet, locally thicker (38 m) accumulations of ice-proximal glaciomarine sediments were deposited, after which rapid retreat took place. Sea-floor morphology indicates that the retreat across Storbanken most likely took place without surging or climatically controlled oscillations.Intense iceberg ploughing characterizes the sea floor down to water depths of 210–220 m. Most of this is relict, but occasional gouges in the shallowest regions may have had a more recent origin. The apparent lower limit of ploughing, interpreted in terms of relative sea level, indicates a rather moderate isostatic depression. This probably resulted from a thin ice sheet, fed from several ice source areas. Depth of the plough marks is largely dependent on thickness of the glaciomarine sediments. A thin and patchy layer of overcompacted till fills local depressions in the sedimentary bedrock surface and forms a flat base for iceberg ploughing.