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Seafloor morphology of the Seafloor morphology of the George V Land shelf, AntarcticaGeorge V Land shelf, Antarctica
Robin J. BeamanRobin J. BeamanSchool of Geography and Environmental Studies, University of Tasmania
?
Australian Marine Science Association Annual Conference, Fremantle, Australia, 10-12 July 2002 2
Commonwealth Bay
Dibble Iceberg Tongue
Terre Adélie
Dumont D’urville
Radarsat ScanSAR7 August, 1999
100 km
Mertz Glacier
George V Land
N
Australian Marine Science Association Annual Conference, Fremantle, Australia, 10-12 July 2002 3
George V Land shelfGeorge V Land shelf
N
Australian Marine Science Association Annual Conference, Fremantle, Australia, 10-12 July 2002 4
Data sets Data sets –– WEGA & NBP0101WEGA & NBP0101
George V Land
MertzGlacier
Mertz BankAdelieBank
100km
N
66°S
144°E
Australian Marine Science Association Annual Conference, Fremantle, Australia, 10-12 July 2002 5
Morphology or acoustic Morphology or acoustic faciesfacies
Damuth (1980) echo types
IA-2
IIB
IIIC
IB
100km
N
66°S
144°E
Australian Marine Science Association Annual Conference, Fremantle, Australia, 10-12 July 2002 6
Type IAType IA--2 (ice2 (ice--keel turbate)keel turbate)
1km
400m
450
500
Australian Marine Science Association Annual Conference, Fremantle, Australia, 10-12 July 2002 7
Type IB (ooze deposits)Type IB (ooze deposits)
1km
800m
825
850
Australian Marine Science Association Annual Conference, Fremantle, Australia, 10-12 July 2002 8
Type IIB (smooth Type IIB (smooth diamictondiamicton))
1km
850m
900
950
Australian Marine Science Association Annual Conference, Fremantle, Australia, 10-12 July 2002 9
Type IIIC (ridges and canyons)Type IIIC (ridges and canyons)
1/2km
400m
450
500
Australian Marine Science Association Annual Conference, Fremantle, Australia, 10-12 July 2002 10
Moraine or ridgeMoraine or ridge
5km
150m
200
250
Australian Marine Science Association Annual Conference, Fremantle, Australia, 10-12 July 2002 11
Mertz Drift Mertz Drift -- hillshadehillshade
Australian Marine Science Association Annual Conference, Fremantle, Australia, 10-12 July 2002 12
IceIce--keel keel turbateturbate
hillshade backscatter
Australian Marine Science Association Annual Conference, Fremantle, Australia, 10-12 July 2002 13
Ooze depositOoze deposit
hillshade backscatter
Australian Marine Science Association Annual Conference, Fremantle, Australia, 10-12 July 2002 14
Ice flowIce flow
100km
N
66°S
144°E
Australian Marine Science Association Annual Conference, Fremantle, Australia, 10-12 July 2002 15
Last Glacial Maximum
CDW
Mertz Glacierice sheet
moraine George V Basin
IA-2
IIB IIIC
Australian Marine Science Association Annual Conference, Fremantle, Australia, 10-12 July 2002 16
Open marine phase
CDWMCDW
HSSW
sea ice
Mertz Glacierice cliff
IA-2
IIB IIIC
IA-2
IB
Australian Marine Science Association Annual Conference, Fremantle, Australia, 10-12 July 2002 17
ConclusionsConclusions•• George V Land shelf is comprised of four George V Land shelf is comprised of four acoustic acoustic faciesfacies types and a lateral morainetypes and a lateral moraine
•• Backscatter interpretation mostly confirms Backscatter interpretation mostly confirms seafloor morphology and seafloor morphology and faciesfacies boundariesboundaries
•• Understanding these features provides a shelfUnderstanding these features provides a shelf--wide interpretation of the wide interpretation of the palaeoenvironmentpalaeoenvironment
•• Seafloor morphology maps will help Seafloor morphology maps will help characterisecharacterise the seabed and be useful for future the seabed and be useful for future studies on marine habitats of the Antarctic shelfstudies on marine habitats of the Antarctic shelf
Australian Marine Science Association Annual Conference, Fremantle, Australia, 10-12 July 2002 18
AcknowledgementsAcknowledgements
•• Dr Richard Coleman Dr Richard Coleman University of TasmaniaUniversity of Tasmania
•• Dr Peter Harris, Mr Rick Smith Dr Peter Harris, Mr Rick Smith GeoscienceGeoscience Australia/Antarctic CRCAustralia/Antarctic CRC
•• Dr Amy Leventer,Dr Amy Leventer,Colgate University, New YorkColgate University, New York