A relative sea-level history for Arviat,Nunavut, and implications for Laurentide Ice Sheet thickness west of Hudson Bay |
| |
| Authors: | Karen M Simon Thomas S James Donald L Forbes Alice M Telka Arthur S Dyke Joseph A Henton |
| |
| Institution: | 1. School of Earth and Ocean Sciences, University of Victoria, Victoria, BC V8P 5C2, Canada;2. Geological Survey of Canada—Pacific, Natural Resources Canada, Sidney, BC V8L 4B2, Canada;3. Geological Survey of Canada—Atlantic, Natural Resources Canada, Dartmouth, NS B2Y 4A2, Canada;4. Department of Geography, Memorial University, St. John''s, NL A1B 3X9, Canada;5. Paleotec Services, Ottawa, ON K1R 5K2, Canada;6. Geological Survey of Canada—Northern, Natural Resources Canada, Ottawa, ON K1A 0E8, Canada;g Canadian Geodetic Survey, Natural Resources Canada, Sidney, BC V8L 4B2, Canada |
| |
| Abstract: | Thirty-six new and previously published radiocarbon dates constrain the relative sea-level history of Arviat on the west coast of Hudson Bay. As a result of glacial isostatic adjustment (GIA) following deglaciation, sea level fell rapidly from a high-stand of nearly 170 m elevation just after 8000 cal yr BP to 60 m elevation by the mid Holocene (~ 5200 cal yr BP). The rate of sea-level fall decreased in the mid and late Holocene, with sea level falling 30 m since 3000 cal yr BP. Several late Holocene sea-level measurements are interpreted to originate from the upper end of the tidal range and place tight constraints on sea level. A preliminary measurement of present-day vertical land motion obtained by repeat Global Positioning System (GPS) occupations indicates ongoing crustal uplift at Arviat of 9.3 ± 1.5 mm/yr, in close agreement with the crustal uplift rate inferred from the inferred sea-level curve. Predictions of numerical GIA models indicate that the new sea-level curve is best fit by a Laurentide Ice Sheet reconstruction with a last glacial maximum peak thickness of ~ 3.4 km. This is a 30–35% thickness reduction of the ICE-5G ice-sheet history west of Hudson Bay. |
| |
| Keywords: | Kivalliq Radiocarbon dating Uplift rate Glacial isostatic adjustment Laurentide Ice Sheet Tyrrell Sea |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
