Late Quaternary deglaciation of Prince William Sound, Alaska
Autor: | Didier Bourlès, Karim Keddadouche, Peter J. Haeussler, Georges Aumaître, Ari Matmon, Maurice Arnold |
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Přispěvatelé: | US Geological Survey [Anchorage], United States Geological Survey [Reston] (USGS), The Hebrew University of Jerusalem (HUJ), Centre européen de recherche et d'enseignement des géosciences de l'environnement (CEREGE), Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE) |
Rok vydání: | 2021 |
Předmět: |
010506 paleontology
geography geography.geographical_feature_category 010504 meteorology & atmospheric sciences [SDU.STU]Sciences of the Universe [physics]/Earth Sciences 01 natural sciences Paleontology Arts and Humanities (miscellaneous) Deglaciation General Earth and Planetary Sciences Quaternary ComputingMilieux_MISCELLANEOUS Geology Sound (geography) 0105 earth and related environmental sciences Earth-Surface Processes |
Zdroj: | Quaternary Research Quaternary Research, 2022, 105, pp.115--134. ⟨10.1017/qua.2021.33⟩ |
ISSN: | 1096-0287 0033-5894 |
Popis: | To understand the timing of deglaciation of the northernmost marine-terminating glaciers of the Cordilleran Ice Sheet (CIS), we obtained 2610Be surface-exposure ages from glacially scoured bedrock surfaces in Prince William Sound (PWS), Alaska. We sampled six elevation transects between sea level and 620 m and spanning a distance of 14 to 70 km along ice flow paths. Most transect age–elevation patterns could not be explained by a simple model of thinning ice; the patterns provide evidence for lingering ice cover and possible inheritance. A reliable set of 20 ages ranges between 17.4 ± 2.0 and 11.6 ± 2.8 ka and indicates ice receded from northwestern PWS around 14.3 ± 1.6 ka, thinned at a rate of ~120–160 m/ka, and retreated from sea-level sites at 12.9 ± 1.1 ka at a rate of 20 m/yr. The retreat rate likely slowed as glaciers retreated into northern PWS. These results are consistent with the growing body of reported deglacial constraints on collapse of ice sheets along the Alaska margin indicating collapse of the CIS soon after 17 ka. These data are consistent with paleotemperature data indicating that a warming North Pacific Ocean caused catastrophic collapse of this part of the CIS. |
Databáze: | OpenAIRE |
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