Switching of a paleo-ice stream in northwest Svalbard

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doi: 10.1016/j.quascirev.2011.03.013
Author(s): Sarkar, Sudipta; Berndt, Christian; Chabert, Anne; Masson, Douglas G.; Minshull, Timothy A.; Westbrook, Graham K.
Author Affiliation(s): Primary:
National Oceanography Centre, Southampton, United Kingdom
Volume Title: Quaternary Science Reviews
Source: Quaternary Science Reviews, 30(13-14), p.1710-1725. Publisher: Elsevier, International. ISSN: 0277-3791
Note: In English. 65 refs.; illus., incl. sects., 1 table, geol. sketch maps
Summary: Ice streams are the fast-flowing zones of ice sheets that can discharge a large flux of ice. The glaciated western Svalbard margin consists of several cross-shelf troughs which are the former ice stream drainage pathways during the Pliocene-Pleistocene glaciations. From an integrated analysis of high-resolution multibeam swath-bathymetric data and several high-resolution two-dimensional reflection seismic profiles across the western and northwestern Svalbard margin we infer the ice stream flow directions and the deposition centres of glacial debris that the ice streams deposited on the outer margin. Our results show that the northwestern margin of Svalbard experienced a switching of a major ice stream. Based on correlation with the regional seismic stratigraphy as well as the results from ODP 911 on Yermak Plateau and ODP 986 farther south on the western margin of Spitsbergen, off Van Mijenfjord, we find that first a northwestward flowing ice stream developed during initial northern hemispheric cooling (starting ∼2.8-2.6 Ma). A switch in ice stream flow direction to the present-day Kongsfjorden cross-shelf trough took place during a glaciation at ∼1.5 Ma or probably later during an intensive major glaciation phase known as the 'Mid-Pleistocene Revolution' starting at ∼1.0 Ma. The seismic and bathymetric data suggest that the switch was abrupt rather than gradual and we attribute it to the reaching of a tipping point when growth of the Svalbard ice sheet had reached a critical thickness and the ice sheet could overcome a topographic barrier. Abstract Copyright (2011) Elsevier, B.V.
Year of Publication: 2011
Research Program: ODP Ocean Drilling Program
Key Words: 12 Stratigraphy, Historical Geology and Paleoecology; 20 Geophysics, Applied; Arctic Ocean; Arctic region; Bathymetry; Cenozoic; Geophysical methods; Geophysical profiles; Geophysical surveys; Glacial environment; Glacial geology; Glaciomarine environment; Ice sheets; Ice streams; Kings Bay; Leg 151; Leg 162; Lithofacies; Lower Pleistocene; Marine environment; Neogene; Norwegian Sea; ODP Site 911; ODP Site 986; Ocean Drilling Program; Paleoenvironment; Pleistocene; Pliocene; Quaternary; Reflection methods; Seismic methods; Seismic profiles; Seismic stratigraphy; Spitsbergen; Surveys; Svalbard; Tertiary; Upper Pliocene; Van Mijenford; Yermak Plateau
Coordinates: N802829 N802829 E0081338 E0081338
N772025 N772025 W0090440 W0090440
N781500 N794500 E0100000 E0070000
Record ID: 2012087085
Copyright Information: GeoRef, Copyright 2019 American Geosciences Institute. Reference includes data from CAPCAS, Elsevier Scientific Publishers, Amsterdam, Netherlands