Southern Weddell Sea shelf edge geomorphology: Implications for gully formation by the overflow of high-salinity water

Gales, J.A.; Larter, R.D. ORCID: https://orcid.org/0000-0002-8414-7389; Mitchell, N.C.; Hillenbrand, C.-D. ORCID: https://orcid.org/0000-0003-0240-7317; Østerhus, S.; Shoosmith, D.R.. 2012 Southern Weddell Sea shelf edge geomorphology: Implications for gully formation by the overflow of high-salinity water. Journal of Geophysical Research, 117 (F4), F04021. 11, pp. 10.1029/2012JF002357

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Abstract/Summary

Submarine gullies are the most common morphological features observed on Antarctic continental slopes. The processes forming these gullies, however, remain poorly constrained. In some areas, gully heads incise the continental shelf edge, and one hypothesis proposed is erosion by overflow of cold, dense water masses formed on the continental shelf. We examined new multibeam echo sounder bathymetric data from the Weddell Sea continental slope, the region that has the highest rate of cold, dense water overflow in Antarctica. Ice Shelf Water (ISW) cascades downslope with an average transport rate of 1.6 Sverdrups (Sv) in the southern Weddell Sea. Our new data show that within this region, ISW overflow does not deeply incise the shelf edge. The absence of gullies extending deeply into the glacial sediments at the shelf edge implies that cold, high salinity water overflow is unlikely to have caused the extensive shelf edge erosion observed on other parts of the Antarctic continental margin. Instead, the gullies observed in the southern Weddell Sea are relatively small and their characteristics indicative accumulation and subsequent failure of proglacial sediment during glacial maxima.

Item Type:	Publication - Article
Digital Object Identifier (DOI):	10.1029/2012JF002357
Programmes:	BAS Programmes > Polar Science for Planet Earth (2009 - ) > Ice Sheets BAS Programmes > Polar Science for Planet Earth (2009 - ) > Polar Oceans
ISSN:	0148-0227
Date made live:	11 Jan 2013 12:21 +0 (UTC)
URI:	https://nora.nerc.ac.uk/id/eprint/21041

Item Type:

Publication - Article

Digital Object Identifier (DOI):

10.1029/2012JF002357

Programmes:

BAS Programmes > Polar Science for Planet Earth (2009 - ) > Ice Sheets
BAS Programmes > Polar Science for Planet Earth (2009 - ) > Polar Oceans

ISSN:

0148-0227

Date made live:

11 Jan 2013 12:21 +0 (UTC)

URI:

https://nora.nerc.ac.uk/id/eprint/21041