期刊
PERMAFROST AND PERIGLACIAL PROCESSES
卷 20, 期 2, 页码 107-125出版社
WILEY
DOI: 10.1002/ppp.647
关键词
Beaufort Shelf; Wisconsinan; palaeoenvironments; permafrost
资金
- Polar Continental Shelf Project
- Aurora Research Institute
- Geological Survey of Canada
The Pleistocene lithostratigraphy exposed on northern Richards Island comprises seven units that correlate with the offshore seismostratigraphy of the eastern Beaufort Continental Shelf. Land-sea correlations, cryostratigraphic observations and proxy indicators of environmental change provide a record of palaeoenvironmental history that commences before the last glacial-interglacial cycle. After the high sea-level stand of the Last (Sangamonian) Interglaciation, marine regression exposed a large area of the eastern Beaufort Shelf to cold subaerial conditions and permafrost aggradation. Northward progradation of a braided river system was abruptly replaced by aeolian activity, probably as a result of diversion of the palaeo-Porcupine River by the advancing Laurentide Ice Sheet during the Late Wisconsinan. Glaciation of Richards Island by the Mackenzie palaeo-ice stream was brief (sometime between similar to 22000 and 16000 cal. yr BP), and deglaciation had certainly commenced by 14300 cal. yr BP and perhaps by similar to 16000 cal. yr BP or earlier. Major fluvial erosion during the Last Glacial-Interglacial Transition incised cross-shelf valleys and formed a regional erosion surface. The Holocene marine transgression trimmed some of the erosion surface and offshore, covered it with marine deposits. Copyright (C) 2009 John Wiley & Sons. Ltd.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据