The structure and effect of suture zones in the Larsen C Ice Shelf, Antarctica
Ice shelf fractures frequently terminate where they encounter suture zones, regions of material heterogeneity that form between meteoric inflows in ice shelves. This heterogeneity can consist of marine ice, meteoric ice with modified rheological properties, or the presence of fractures. Here, we use...
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ftcdlib:oai:escholarship.org/ark:/13030/qt4158p0f9 2023-05-15T13:39:57+02:00 The structure and effect of suture zones in the Larsen C Ice Shelf, Antarctica McGrath, D Steffen, K Holland, PR Scambos, T Rajaram, H Abdalati, W Rignot, E 588 - 602 2014-01-01 application/pdf https://escholarship.org/uc/item/4158p0f9 unknown eScholarship, University of California qt4158p0f9 https://escholarship.org/uc/item/4158p0f9 CC-BY CC-BY Journal of Geophysical Research: Earth Surface, vol 119, iss 3 ice shelves suture zone fracture GPR article 2014 ftcdlib 2020-03-20T23:55:55Z Ice shelf fractures frequently terminate where they encounter suture zones, regions of material heterogeneity that form between meteoric inflows in ice shelves. This heterogeneity can consist of marine ice, meteoric ice with modified rheological properties, or the presence of fractures. Here, we use radar observations on the Larsen C Ice Shelf, Antarctica, to investigate (i) the termination of a 25 km long rift in the Churchill Peninsula suture zone, which was found to contain ~60 m of accreted marine ice, and (ii) the along-flow evolution of a suture zone originating at Cole Peninsula. We determine a steady state field of basal melting/freezing rates and apply it to a flowline model to delineate the along-flow evolution of layers within the ice shelf. The thickening surface wedge of locally accumulated meteoric ice, which likely has limited lateral variation in its mechanical properties, accounts for ~60% of the total ice thickness near the calving front. Thus, we infer that the lower ~40% of the ice column and the material heterogeneities present there are responsible for resisting fracture propagation and thereby delaying tabular calving events, as demonstrated in the >40 year time series leading up to the 2004/2005 calving event for Larsen C. This likely represents a highly sensitive aspect of ice shelf stability, as changes in the oceanic forcing may lead to the loss of this heterogeneity. ©2014. American Geophysical Union. All Rights Reserved. Article in Journal/Newspaper Antarc* Antarctica Ice Shelf Ice Shelves University of California: eScholarship Churchill Peninsula ENVELOPE(-62.781,-62.781,-66.440,-66.440) Cole peninsula ENVELOPE(-63.969,-63.969,-66.845,-66.845) |
institution |
Open Polar |
collection |
University of California: eScholarship |
op_collection_id |
ftcdlib |
language |
unknown |
topic |
ice shelves suture zone fracture GPR |
spellingShingle |
ice shelves suture zone fracture GPR McGrath, D Steffen, K Holland, PR Scambos, T Rajaram, H Abdalati, W Rignot, E The structure and effect of suture zones in the Larsen C Ice Shelf, Antarctica |
topic_facet |
ice shelves suture zone fracture GPR |
description |
Ice shelf fractures frequently terminate where they encounter suture zones, regions of material heterogeneity that form between meteoric inflows in ice shelves. This heterogeneity can consist of marine ice, meteoric ice with modified rheological properties, or the presence of fractures. Here, we use radar observations on the Larsen C Ice Shelf, Antarctica, to investigate (i) the termination of a 25 km long rift in the Churchill Peninsula suture zone, which was found to contain ~60 m of accreted marine ice, and (ii) the along-flow evolution of a suture zone originating at Cole Peninsula. We determine a steady state field of basal melting/freezing rates and apply it to a flowline model to delineate the along-flow evolution of layers within the ice shelf. The thickening surface wedge of locally accumulated meteoric ice, which likely has limited lateral variation in its mechanical properties, accounts for ~60% of the total ice thickness near the calving front. Thus, we infer that the lower ~40% of the ice column and the material heterogeneities present there are responsible for resisting fracture propagation and thereby delaying tabular calving events, as demonstrated in the >40 year time series leading up to the 2004/2005 calving event for Larsen C. This likely represents a highly sensitive aspect of ice shelf stability, as changes in the oceanic forcing may lead to the loss of this heterogeneity. ©2014. American Geophysical Union. All Rights Reserved. |
format |
Article in Journal/Newspaper |
author |
McGrath, D Steffen, K Holland, PR Scambos, T Rajaram, H Abdalati, W Rignot, E |
author_facet |
McGrath, D Steffen, K Holland, PR Scambos, T Rajaram, H Abdalati, W Rignot, E |
author_sort |
McGrath, D |
title |
The structure and effect of suture zones in the Larsen C Ice Shelf, Antarctica |
title_short |
The structure and effect of suture zones in the Larsen C Ice Shelf, Antarctica |
title_full |
The structure and effect of suture zones in the Larsen C Ice Shelf, Antarctica |
title_fullStr |
The structure and effect of suture zones in the Larsen C Ice Shelf, Antarctica |
title_full_unstemmed |
The structure and effect of suture zones in the Larsen C Ice Shelf, Antarctica |
title_sort |
structure and effect of suture zones in the larsen c ice shelf, antarctica |
publisher |
eScholarship, University of California |
publishDate |
2014 |
url |
https://escholarship.org/uc/item/4158p0f9 |
op_coverage |
588 - 602 |
long_lat |
ENVELOPE(-62.781,-62.781,-66.440,-66.440) ENVELOPE(-63.969,-63.969,-66.845,-66.845) |
geographic |
Churchill Peninsula Cole peninsula |
geographic_facet |
Churchill Peninsula Cole peninsula |
genre |
Antarc* Antarctica Ice Shelf Ice Shelves |
genre_facet |
Antarc* Antarctica Ice Shelf Ice Shelves |
op_source |
Journal of Geophysical Research: Earth Surface, vol 119, iss 3 |
op_relation |
qt4158p0f9 https://escholarship.org/uc/item/4158p0f9 |
op_rights |
CC-BY |
op_rightsnorm |
CC-BY |
_version_ |
1766126413691224064 |