Past ice-sheet flow east of Svalbard inferred from streamlined subglacial landforms
2013-09-06T09:34:00Z (GMT) by
The pattern of late Weichselian (ca. 20 ka) ice flow in the northern Barents Sea is not well known, due mainly to a lack of marine data east of Svalbard. Several years with little summer sea ice have allowed acquisition of swath-bathymetric imagery of well-preserved subglacial landforms characterizing late Weichselian ice-flow directions over ∼150,000 km2 of the northwestern Barents Sea. We show that a major ice dome was located on easternmost Spitsbergen or southern Hinlopen Strait, at least 500 km west of its previously inferred position in the northern Barents Sea. This dome controlled the regional flow pattern; ice flowed eastward around Kong Karls Land into Franz Victoria Trough and north through Hinlopen Strait. An ice dome west of Kong Karls Land is required to explain the observed ice-flow pattern, but does not preclude an additional ice dome to the southeast. Discrepancies with earlier ice-sheet reconstructions reflect the lack of previous seafloor observations, with evidence limited mainly to past ice loading and postglacial rebound. The new pattern of ice-flow directions shows predominantly eastward rather than northward flow, with Franz Victoria Trough a major drainage pathway with a full-glacial balance flux of >40 km3 yr−1.