2006 Voyage
The University of the Sea 2006 cruise departs from Auckland
on February 7 and goes via Noumea, to finish in Sydney on February
26. The shipboard programme is supervised by Drs Jock Keene
and Julie Dickinson from the University of Sydney, Dr Greg Skilbeck
from the University of Technology Sydney, and Professor Patrick
De Deckker from the Australian National University. The University
of the Sea students will be joining a research program developed
by marine geoscientists from Geoscience Australia. It is part
of their 'Lord Howe Rise Project' to evaluate the gas hydrates
('frozen' methane) in the sediments.
Geoscience Australia's survey primarily involves the collection
of six giant CALYPSO piston cores over areas of possible gas
hydrate (bottom simulating reflectors, BSRs) on the northern
Lord Howe Rise. The targets are areas of seafloor underlain
(at a depth of 500 to 600m below the seafloor) by BSRs on
the western flank of the Fairway Basin and the central part
of the Capel Basin identified on Geoscience Australia multi-channel
seismic lines collected in 1996 and 1998. Previous coring
in the region using standard piston and gravity corers (typically
recovery of 4 - 5 metres length) failed to get below the surface
oxidation layer and therefore failed to produce unequivocal
geochemical evidence of the presence of gas hydrates at depth.
It is expected that the use of the CALYPSO corer with typical
recovery of 40 to 60 m will overcome this problem. Pore water
and head space gas samples will be collected from the cores
and then analysed on shore.
In addition to the coring program, swath, sub-bottom profiler,
gravity and magnetometer data will be collected on transits
to and from the sampling sites. These data will provide detailed
information on the bathymetry and structure of the seafloor
and underlying geology, particularly of the continental margin
of central and northern New South Wales and of the eastern
flank of the Lord Howe Rise. Also, a small number of dredge
hauls may be taken during the swath mapping on the eastern
flank of the Rise if suitable sites are identified to target
the nature of basement or syn-rift rocks.
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