Title Rates of sediment delivery from the Fennoscandian ice sheet through an ice age
Author Dowdeswell, J.A.; Ottesen, D.; Rise, L.
Author Affil Dowdeswell, J.A., University of Cambridge, Scott Polar Research Institute, Cambridge, United Kingdom. Other: Geological Survey of Norway, Norway
Source Geology (Boulder), 38(1), p.3-6, . Publisher: Geological Society of America (GSA), Boulder, CO, United States. ISSN: 0091- 7613
Publication Date Jan. 2010
Notes In English. 31 refs. GeoRef Acc. No: 297066
Index Terms erosion; geophysical surveys; glacial erosion; glacial geology; ice sheets; sedimentation; seismic surveys; surveys; Norway; Norwegian Sea; Arctic Ocean; Cenozoic; continental margin sedimentation; Europe; geophysical methods; glacial environment; glacial sedimentation; interglacial environment; Naust Formation; Neogene; Pliocene; Quaternary; Scandinavia; Scandinavian ice sheet; sedimentation rates; seismic methods; Tertiary; three-dimensional models; two-dimensional models; upper Pliocene; upper Quaternary; Western Europe
Abstract Sediment delivery rates through an entire ice age are investigated using seismic records of glacial erosion products from the Fennoscandian Ice Sheet deposited offshore of mid-Norway in the 2.7 m.y. old Naust Formation (volume 100,000 km3). The mean sedimentation rate over the ice age is ~0.24 m k.y.-1, with bedrock lowering of ~520 m in the ice-sheet catchment. The mean sediment delivery is 2-3 times higher for the most recent 600 k.y. than for earlier Naust sequences. The hypothesis that glacial erosion is most rapid early in an ice age, when there was presumably much weathered bedrock and preglacial sediment available, is not accepted for our study area. More important are changing ice-sheet dimensions and dynamics, varying intensity of individual glacial cycles, and complex ice-sheet dynamics in single deglaciations. The mean rate of sediment delivery from ice sheets is an order of magnitude higher than from fluvial activity in the huge Amazon and Mississippi systems, implying that ice is a very effective agent of long-term denudation during cold periods of Earth history.
URL http://hdl.handle.net/10.1130/G25523.1
Publication Type journal article
Record ID 64002158