Comment on Shaw J., Pugin, A. and Young, R. (2008): "A meltwater origin for Antarctic shelf bedforms with special attention to megalineations", Geomorphology 102, 364-375
O Cofaigh, Colm; Dowdeswell, Julian A.; King, Edward C.; Anderson, John B.; Clark, Chris D.; Evans, David J.A.; Evans, Jeffrey; Hindmarsh, Richard C.A.; Larter, Robert D.; Stokes, Chris R.. 2010 Comment on Shaw J., Pugin, A. and Young, R. (2008): "A meltwater origin for Antarctic shelf bedforms with special attention to megalineations", Geomorphology 102, 364-375. Geomorphology, 117 (1-2). 195-198. 10.1016/j.geomorph.2009.09.036Full text not available from this repository.
The submarine glacial geomorphology and sedimentology of the cross-shelf troughs and the adjacent continental slope around the Antarctic Peninsula and West Antarctica have been the focus of a series of marine geophysical and geological investigations over the last decade (e.g., [Shipp et al., 1999], [Canals et al., 2000], [Wellner et al., 2001], [Lowe and Anderson, 2002], [Ó Cofaigh et al., 2002], [Dowdeswell et al., 2004], [Heroy and Anderson, 2005], [Evans et al., 2005], [Domack et al., 2006], [Mosola and Anderson, 2006], [Wellner et al., 2006], [Dowdeswell et al., 2006], [Ó Cofaigh et al., 2007], Ó Cofaigh et al., 2008 C. Ó Cofaigh, J.A. Dowdeswell, J. Evans and R.D. Larter, Geological constraints on Antarctic palaeo-ice stream retreat, Earth Surface Processes and Landforms 33 (2008), pp. 513–525.[Ó Cofaigh et al., 2008] and [Dowdeswell et al., 2008]). These studies have interpreted sets of characteristic streamlined glacial bedforms and sediments on the shelf, which in numerous cases occur in front of modern ice streams, as largely the product of fast-flowing palaeo-ice streams that drained across the shelf during or following the last glacial maximum. A key feature of these studies is the observation of highly attenuated bedforms known as mega-scale glacial lineations (MSGL), formed in soft sediment on the outer continental shelf. These lineations are regarded as key evidence for streaming flow. In their recent paper, Shaw et al. present a radically different interpretation of the glacial geomorphology of Antarctic cross-shelf troughs in terms of catastrophic discharge of subglacial meltwater floods across the shelf. In their interpretation, MSGL are regarded as the product of erosion by turbulent meltwater flow. The following comment discusses a number of the key assertions made in their paper.
|Programmes:||BAS Programmes > Polar Science for Planet Earth (2009 - ) > Ice Sheets|
|NORA Subject Terms:||Marine Sciences
|Date made live:||20 Aug 2010 12:42|
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