Arctic and Antarctic submarine gullies – a comparison of high latitude continental margins

Gales, J.A.; Forwick, M.; Laberg, J.S.; Vorren, T.O.; Larter, R.D. ORCID: https://orcid.org/0000-0002-8414-7389; Graham, A.G.C.; Baeten, N.J.; Amundsen, H.B.. 2013 Arctic and Antarctic submarine gullies – a comparison of high latitude continental margins. Geomorphology, 201. 449-461. 10.1016/j.geomorph.2013.07.018

Before downloading, please read NORA policies.

Preview

Text (This article has been accepted for publication and will appear in a revised form in Geomorphology, published by Elsevier. Copyright Elsevier) 1-s2.0-S0169555X1300367X-main.pdf - Accepted Version Download (1MB) | Preview

Abstract/Summary

Submarine gullies are common features of high latitude continental slopes and, over the last decade, have been shown to play a key role in continental margin evolution, submarine erosion, downslope sediment transport, slope deposits, and the architecture of petroleum reservoirs. However, the processes that form these gullies, the timescales over which they develop, and the environmental controls influencing their morphology remain poorly constrained. We present the first systematic and comparative analysis between Arctic and Antarctic gullies with the aim of identifying differences in slope character, from which we infer differences in processes operating in these environments. Quantitative analysis of multibeam echosounder data along 2469 km of the continental shelf and upper slope and morphometric signatures of over 1450 gullies show that six geomorphically distinct gully types exist on high latitude continental margins. We identify distinct differences between Arctic and Antarctic gully morphologies. In the Arctic data sets, deep relief (> 30 m gully incision depth at 50 m below the shelf edge) and shelf-incising gullies are lacking. These differences have implications for the timescales over which the gullies were formed and for the magnitude of the flows that formed them. We consider two hypotheses for these differences: (1) some Antarctic gullies developed through several glacial cycles; and (2) larger Antarctic gullies were formed since the Last Glacial Maximum as a result of erosive flows (i.e., sediment-laden subglacial meltwater) being more abundant on parts of the Antarctic margin over longer timescales. A second difference is that unique gully signatures are observed on Arctic and on Antarctic margins. Environmental controls, such as the oceanographic regime and geotechnical differences, may lead to particular styles of gully erosion observed on Arctic and Antarctic margins.

Item Type:	Publication - Article
Digital Object Identifier (DOI):	10.1016/j.geomorph.2013.07.018
Programmes:	BAS Programmes > Polar Science for Planet Earth (2009 - ) > Ice Sheets
ISSN:	0169555X
Additional Keywords:	geomorphology, submarine gully, continental margin, sedimentary processes, Antarctic, Arctic
Date made live:	24 Jul 2013 10:36 +0 (UTC)
URI:	https://nora.nerc.ac.uk/id/eprint/502730

Actions (login required)

View Item

Document Downloads

More statistics for this item...