10 Be data from meltwater channels suggest that Jameson Land, east Greenland, was ice-covered during the last glacial maximum

Abstract Along the northeast Greenland continental margin, bedrock on interfjord plateaus is highly weathered, whereas rock surfaces in fjord troughs are characterized by glacial scour. Based on the intense bedrock weathering and lack of glacial deposits from the last glaciation, interfjord plateaus...

Full description

Bibliographic Details
Published in:Quaternary Research
Main Authors: Håkansson, Lena, Briner, Jason P., Aldahan, Ala, Possnert, Göran
Format: Article in Journal/Newspaper
Language:English
Published: Cambridge University Press (CUP) 2011
Subjects:
Online Access:http://dx.doi.org/10.1016/j.yqres.2011.06.007
http://api.elsevier.com/content/article/PII:S0033589411000834?httpAccept=text/xml
http://api.elsevier.com/content/article/PII:S0033589411000834?httpAccept=text/plain
https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0033589400008061
Description
Summary:Abstract Along the northeast Greenland continental margin, bedrock on interfjord plateaus is highly weathered, whereas rock surfaces in fjord troughs are characterized by glacial scour. Based on the intense bedrock weathering and lack of glacial deposits from the last glaciation, interfjord plateaus have long been thought to be ice-free throughout the last glacial maximum (LGM). In recent years there is growing evidence from shelf and fjord settings that the northeast Greenland continental margin was more extensively glaciated during the LGM than previously thought. However, little is still known from interfjord settings. We present cosmogenic 10 Be data from meltwater channels and weathered sandstone outcrops on Jameson Land, an interfjord highland north of Scoresby Sund. The mean exposure age of samples from channel beds (n = 3) constrains on the onset of deglaciation on interior Jameson Land to 18.5 ± 1.3–21.4 ± 1.9 ka (for erosion conditions of 0–10 mm/ka, respectively). This finding adds to growing evidence that the northeast Greenland continental margin was more heavily glaciated during the LGM than previously thought.