An Early or Middle Weichselian sequence of proglacial, shallow marine sediments on western Svalbard |
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| Authors: | IDA LONNE JAN MANGERUD |
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| Institution: | University of Bergen, Department of Geology, Section B, Allégt. 41, N-5007 Bergen, Norway;University of Bergen, Department of Geology, Section B, Allégt. 41, N-5007 Bergen, Norway;29th May, 1990 |
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| Abstract: | A 20 m thick shallow marine sequence, capped by a Late Weichselian lodgement till, is exposed for 200111 along the river in Linnedalen on the west coast of Svalbard. Five formations are recognized: Formation A, the oldest, consists of a shallow marine, proglacial fan, of channelized sandy turbidites, possibly fed from an ice-contact deposit. Formation B, a sequence of proglacial channels and ice-rafted debris, was formed during a small oscillation of the glacier. Formation C, a prograding, storm-dominated shoreline sequence, was formed during a sea level fall, assumed to be a result of glacio-isostatic uplift.
Formation D, a lodgement till formed during the last glacier advance in Linnedalen and formation E, a coarsening upwards sequence, were formed during the post-glacial sea level fall. The subtill sequence (fm. A, B and C) is dated to between 40,000BP (radiocarbon dates) and 120,000BP (thermoluminescence and amino acid D/L ratios). The glacier front was 10 km downvalley during deposition of formations A and B, relative to the present glacier terminus, and more than 12km during the late Weichselian maximum. |
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