1. Byrd Polar Research Center, Ohio State University, Columbus, Ohio 43210, USA
2. Hawaii Mapping Research Group, Hawaii Institute of Geophysics and Planetology, University of Hawaii, Honolulu, Hawaii 96822, USA
3. Department of Geology, Tulane University, New Orleans, Louisiana 70118, USA
4. Department of Geology and Geochemistry, Stockholm University, 106 91 Stockholm, Sweden
5. Present address: Center for Coastal Mapping, University of New Hampshire, Durham, New Hampshire 03824, USA.

Correspondence to: Leonid Polyak¹ Correspondence and requests for materials should be addressed to L.P. (e-mail: Email: polyak.1@osu.edu).

Abstract

It has been proposed that during Pleistocene glaciations, an ice cap of 1 kilometre or greater thickness covered the Arctic Ocean^{1, 2, 3}. This notion contrasts with the prevailing view that the Arctic Ocean was covered only by perennial sea ice with scattered icebergs^{4, 5, 6}. Detailed mapping of the ocean floor is the best means to resolve this issue. Although sea-floor imagery has been used to reconstruct the glacial history of the Antarctic shelf ^{7, 8, 9}, little data have been collected in the Arctic Ocean because of operational constraints^{10, 11}. The use of a geophysical mapping system during the submarine SCICEX expedition in 1999¹² provided the opportunity to perform such an investigation over a large portion of the Arctic Ocean. Here we analyse backscatter images and sub-bottom profiler records obtained during this expedition from depths as great as 1 kilometre. These records show multiple bedforms indicative of glacial scouring and moulding of sea floor, combined with large-scale erosion of submarine ridge crests. These distinct glaciogenic features demonstrate that immense, Antarctic-type ice shelves up to 1 kilometre thick and hundreds of kilometres long existed in the Arctic Ocean during Pleistocene glaciations.

1. Byrd Polar Research Center, Ohio State University, Columbus, Ohio 43210, USA
2. Hawaii Mapping Research Group, Hawaii Institute of Geophysics and Planetology, University of Hawaii, Honolulu, Hawaii 96822, USA
3. Department of Geology, Tulane University, New Orleans, Louisiana 70118, USA
4. Department of Geology and Geochemistry, Stockholm University, 106 91 Stockholm, Sweden
5. Present address: Center for Coastal Mapping, University of New Hampshire, Durham, New Hampshire 03824, USA.

Correspondence to: Leonid Polyak¹ Correspondence and requests for materials should be addressed to L.P. (e-mail: Email: polyak.1@osu.edu).