Timing and character of the last interglacial-glacial transition in the eastern Canadian Arctic and Northwest Greenland

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doi: 10.1130/SPE270-p223
Author(s): Miller, Gifford H.; Funder, Svend; de Vernal, Anne; Andrews, John T.
Author Affiliation(s): Primary:
University of Colorado, Institute of Arctic and Alpine Research, Boulder, CO, United States
Other:
Bowdoin College, United States
Geological Museum, Denmark
Université du Québec à Montréal, Canada
Volume Title: Last interglacial-glacial transition in North America
Volume Author(s): Clark, Peter U., editor; Lea, Peter D.
Source: The last interglacial-glacial transition in North America, edited by Peter U. Clark and Peter D. Lea. Special Paper - Geological Society of America, Vol.270, p.223-231. Publisher: Geological Society of America (GSA), Boulder, CO, United States. ISSN: 0072-1077. ISBN: 0813722705 CODEN: GSAPAZ
Note: In English. 49 refs.; illus. incl. sect., sketch maps
Summary: The records of glaciation and climate change preserved in sediments on the Canadian and northwest Greenland margins of Baffin Bay pertaining to the last interglacial-glacial transition are remarkably similar. In both regions, warmer than present terrestrial and nearshore marine facies of the last interglacial sensu stricto (s.s.) are overlain by glacial sediments that represent the most extensive advance of continental ice during the last glaciation. Chronometric controls (14C, thermoluminescence, amino acids) indicate an isotope stage 5 age for this advance. Evidence for extensive high-latitude glacial erosion during stage 5 is recorded by abundant pre-Quaternary palynomorphs in Baffin Bay sediment cores, in contrast to a much reduced flux during the remainder of the last glaciation. Warm nearshore marine conditions (seasonally ice free) also occurred near the end of stage 5 along both the eastern Baffin Island and northwest Greenland coasts after the maximum glacial advance; surface water in central Baffin Bay apparently was dominated by meltwater at this time. Subsequently (isotope stages 4, 3, and 2), terrestrial conditions were colder and drier, sea-surface temperatures were lower, and ice margins were retracted. Minimum summer insolation at high latitudes, coupled with mild winters and vigorous meridional oceanic (and presumably atmospheric) circulation characterized the inception phase of the last glaciation during isotope stage 5. In contrast, the 20 ka B.P. (isotope stage 2) "last glacial maximum" was characterized by a zonal circulation regime that resulted in cold and dry conditions over Baffin Bay; the margins of the northwest Greenland and northeast Laurentide ice sheets did not extend beyond the fiords at this time.
Year of Publication: 1992
Research Program: ODP Ocean Drilling Program
Key Words: 24 Surficial Geology, Quaternary Geology; Absolute age; Amino acids; Arctic Archipelago; Arctic region; Atlantic Ocean; C-14; Canada; Carbon; Cores; Correlation; Dates; Franklin District Northwest Territories; Glacial environment; Glaciation; Greenland; Interglacial environment; Isotopes; Labrador Sea; Laurentide ice sheet; Leg 105; Marine environment; Microfossils; North American Atlantic; North Atlantic; Northwest Territories; Northwestern Greenland; ODP Site 645; ODP Site 646; ODP Site 647; Ocean Drilling Program; Organic acids; Organic compounds; Organic materials; Paleoclimatology; Palynomorphs; Radioactive isotopes; Sediments; Thermoluminescence; Ungava; Western Canada
Coordinates: N702730 N702730 W0643924 W0643924
N581236 N581236 W0482206 W0482206
N531954 N531954 W0451542 W0451542
Record ID: 1993006651
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