A relative sea-level history for Arviat, Nunavut, and implications for Laurentide Ice Sheet thickness west of Hudson Bay

• Published in: Quaternary Research
• Main Authors: Simon, Karen M., James, Thomas S., Forbes, Donald L., Telka, Alice M., Dyke, Arthur S., Henton, Joseph A.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Cambridge University Press (CUP) 2014
• Subjects: Nunavut; Hudson Bay; Hudson; Arviat; Ice Sheet
• Online Access: https://doi.org/10.1016/j.yqres.2014.04.002; http://api.elsevier.com/content/article/PII:S0033589414000416?httpAccept=text/xml; http://api.elsevier.com/content/article/PII:S0033589414000416?httpAccept=text/plain; https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S003358940000942X

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.