Cosmogenic 10Be and 26Al ages for the Last Glacial Maximum, eastern Baffin Island, Arctic Canada

Abstract

Research Article| August 01, 2000 Cosmogenic 10Be and 26Al ages for the Last Glacial Maximum, eastern Baffin Island, Arctic Canada Kimberly A. Marsella; Kimberly A. Marsella 1Geology Department, University of Vermont, Burlington, Vermont 05405, USA Search for other works by this author on: GSW Google Scholar Paul R. Bierman; Paul R. Bierman 1Geology Department, University of Vermont, Burlington, Vermont 05405, USA Search for other works by this author on: GSW Google Scholar P. Thompson Davis; P. Thompson Davis 2Department of Natural Sciences, Bentley College, Waltham, Massachusetts 02452, USA Search for other works by this author on: GSW Google Scholar Marc W. Caffee Marc W. Caffee 3Center for Accelerator Mass Spectrometry, Lawrence Livermore National Laboratory, Livermore, California 94550, USA Search for other works by this author on: GSW Google Scholar GSA Bulletin (2000) 112 (8): 1296–1312. https://doi.org/10.1130/0016-7606(2000)112<1296:CBAAAF>2.0.CO;2 Article history received: 14 May 1999 rev-recd: 23 Jul 1999 accepted: 16 Sep 1999 first online: 01 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share Twitter LinkedIn Tools Icon Tools Get Permissions Search Site Citation Kimberly A. Marsella, Paul R. Bierman, P. Thompson Davis, Marc W. Caffee; Cosmogenic 10Be and 26Al ages for the Last Glacial Maximum, eastern Baffin Island, Arctic Canada. GSA Bulletin 2000;; 112 (8): 1296–1312. doi: https://doi.org/10.1130/0016-7606(2000)112<1296:CBAAAF>2.0.CO;2 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGSA Bulletin Search Advanced Search Abstract A chronology for the Last Glacial Maximum based on cosmogenic exposure dating in the Pangnirtung Fjord area, eastern Baffin Island, Arctic Canada, is at odds with many decades of land-based, glacial stratigraphic research. Most previous chronologies focused primarily on relative weathering criteria and suggested that ice extent was restricted during the late Wisconsinan (ca. 24–8 ka). In contrast, by directly dating glacial features, we conclude that late Wisconsinan ice was far more extensive than previously believed.There are 36 gneissic boulders and 8 samples of ice-molded gneissic bedrock that yield late Wisconsinan 10Be and 26Al exposure ages for the last glaciation of Pangnirtung Fjord. The prominent Duval moraines, which were previously interpreted to represent a significant early Wisconsinan (100–60 ka) ice advance on southern Cumberland Peninsula, were actually deposited between 24 and 9 ka. Two boulders from a raised glaciomarine delta, stratigraphically related to the Duval moraines, date to about 10 ka. Two recessional moraines and striated bedrock along Pangnirtung Fjord, as well as erratics on the floor of the Kolik River valley, a tributary to Pangnirtung Fjord, indicate that deglaciation began between 12 and 9 ka.In situ produced 10Be and 26Al abundances indicate that ice filled Pangnirtung Fjord for about 15 k.y. (either continuously or intermittently) prior to 10 ka, which is compatible with 14C chronologies for adjacent Cumberland Sound. Thus, our data support other recent studies that suggest the northern and southern margins of the Laurentide ice sheet were generally in phase during the latest Wisconsinan, contrary to earlier interpretations. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.