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Recent exploration for drift Recent exploration for drift deposits on the continental deposits on the continental
shelf of East Antarcticashelf of East Antarctica
Rob BeamanRob Beaman
Fifth Australian Marine Geoscience Conference, Hobart, Australia, 27-29 June 2001 2
Fifth Australian Marine Geoscience Conference, Hobart, Australia, 27-29 June 2001 3
Fifth Australian Marine Geoscience Conference, Hobart, Australia, 27-29 June 2001 4
Fifth Australian Marine Geoscience Conference, Hobart, Australia, 27-29 June 2001 5
Fifth Australian Marine Geoscience Conference, Hobart, Australia, 27-29 June 2001 6
Fifth Australian Marine Geoscience Conference, Hobart, Australia, 27-29 June 2001 7
Fifth Australian Marine Geoscience Conference, Hobart, Australia, 27-29 June 2001 8
Fifth Australian Marine Geoscience Conference, Hobart, Australia, 27-29 June 2001 9
MethodsMethods
Radiocarbon samplesRadiocarbon samples
Seafloor photographs Seafloor photographs
XX--radiographs: radiographs: -- iceice--rafted debris (IRD) gravel content rafted debris (IRD) gravel content -- classify facies within coresclassify facies within cores
Fifth Australian Marine Geoscience Conference, Hobart, Australia, 27-29 June 2001 10
massively bedded SMOmassively bedded SMO
0cm
10
Fifth Australian Marine Geoscience Conference, Hobart, Australia, 27-29 June 2001 11
massively bedded massively bedded fine sand/SMOfine sand/SMO
0cm
10
Fifth Australian Marine Geoscience Conference, Hobart, Australia, 27-29 June 2001 12
laminated SMOlaminated SMO
0cm
10
Fifth Australian Marine Geoscience Conference, Hobart, Australia, 27-29 June 2001 13
cross laminated SMOcross laminated SMO
0cm
10
Fifth Australian Marine Geoscience Conference, Hobart, Australia, 27-29 June 2001 14
diamictondiamicton
0cm
10
Fifth Australian Marine Geoscience Conference, Hobart, Australia, 27-29 June 2001 15
Facies successionFacies succession
(4) massively bedded fine sand/SMO Present
3000 yr BP
(3) laminated SMO and
cross laminated SMO
(1) diamictonLGM
5000 yr BP(2) massively bedded SMO
14,000 yr BP
Fifth Australian Marine Geoscience Conference, Hobart, Australia, 27-29 June 2001 16
Glacial retreat phaseGlacial retreat phase14,00014,000--5000 yr BP5000 yr BP
0 m
200
200
400
600
800
1000
1200
CDW
HSSW
Fifth Australian Marine Geoscience Conference, Hobart, Australia, 27-29 June 2001 17
Climate optimum phaseClimate optimum phase50005000--3000 yr BP3000 yr BP
0 m
200
200
400
600
800
1000
1200
CDWHSSW
Fifth Australian Marine Geoscience Conference, Hobart, Australia, 27-29 June 2001 18
Modern phaseModern phase3000 yr BP3000 yr BP--presentpresent
0 m
200
200
400
600
800
1000
1200
CDWHSSW
Fifth Australian Marine Geoscience Conference, Hobart, Australia, 27-29 June 2001 19
ConclusionConclusion
Mertz Drift sediments possibly show Mertz Drift sediments possibly show annual seasonal cycles.annual seasonal cycles.
Mertz Drift sediments do reflect intensity Mertz Drift sediments do reflect intensity in bottom currents.in bottom currents.
Mertz Drift sediments do record a high Mertz Drift sediments do record a high resolution of environmental change.resolution of environmental change.
