CGRG Bibliography of Canadian Geomorphology
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Author : Black, J.L.; and 23 other contributors
Date : 2009.
Title : A paleoenvironmental reconstruction of Pingualuit Crater Lake sediments: A long-term record in the terrestrial Canadian Arctic spanning more than 200,000 years.
Publication : Retrospective Views on Our Planet's Future. Past Global Changes (PAGES) 3rd Open Science Meeting. July 8-11, 2009. Corvallis, Oregon, USA.
Issue : Program and Abstracts Volume:
Page(s) : 77.
Abstract
The sediments of the 1.4 Ma old Pingualuit Crater Lake offer the unique opportunity to study terrestrial climate dynamics not only during the postglacial period, but over several hundreds of thousands of years as its deep sediment infill yields an uninterrupted arctic paleoclimate record covering several interglacial-glacial cycles. The Pingualuit meteoritic crater (Nunavik, Canada; 61°17’N, 73°41’W) is located in the northernmost part of the Ungava Peninsula in northern Quebec—close to the area where the Laurentide Ice Sheet reached maximum thickness during the last (Wisconsinan) glaciation. Here we present results of limnological measurements (PAR, UV light transparency), sedimentological (grain size, MS, ITRAX, ICPMS), micropaleontological (diatom and pollen), and stratigraphic interpretations of Pingualuit Crater Lake sediments. There are two decimetre-thick intervals in addition to the uppermost Holocene sediments composed of laminated, dark grey clayey-silts characterized by a relatively low density and magnetic susceptibility, that contrast sharply with the thicker over- and underlying sections with light grey, denser, sandy sediments. Moreover, these two intervals contain fossil diatoms and chrysophytes, suggesting that these two intervals represent ice-free conditions and thus interglacials, whereas the more extensive light grey and sandy sediments reflect glacial intervals. Initial TL dates indicate the first interglacial after the Holocene corresponds to MIS 5d and the second interglacial corresponds to MIS 7. The timing and magnitude of the interglacial periods have been reconstructed from Pingualuit Crater Lake and will be compared with other records from around the Arctic
Bibliography of Canadian Geomorphology