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National News
National News
Australia
Jo Whittaker
Australia has one of the world’s largest marine territories, much of
which remains unexplored, with only one blue-water research vessel
available to our marine research community. In an exciting
development, Australia has commissioned a new research vessel, the
RV Investigator. The Marine National Facility’s new state-of-the-art
research facility is currently under construction. Following a
commissioning year in 2013-2014, RV Investigator will be available
for research in 2014-2015. The new vessel will be capable of
operating continuously for 60 days at sea, cruising at 12 knots over
a range of 10,000 nautical miles.
RV Investigator will be a highly advanced research vessel with a broad
range of scientific equipment to support marine scientists, including
a wide range of marine geosciences, oceanography and climatology,
and fisheries, marine ecosystem and marine environmental research.
Additionally, through the AuScope’s Australian Geophysical
Observing System (AGOS), Australia has committed to acquiring
20 Ocean Bottom Seismometers by 2014, an addition that will be
invaluable to geophysical exploration of the ocean basins
surrounding Australia.
In November 2011, Dr Simon Williams from the University of
Sydney led a successful international team on a scientific voyage to
the Perth Abyssal Plain. The Perth Abyssal Plain is one of the more
poorly understood ocean basins surrounding Australia. The cruise
collected magnetic, bathymetric and dredge data to address
knowledge gaps regarding the nature and evolution of the basin.
The voyage achieved its scientific aims including the collection of six
magnetic anomaly profiles across the Perth Abyssal Plain, and the
collection of swath and dredge data from seven sites on the Batavia
Knoll, Gulden Draak Ridge and Dirck Hartog Ridge. Continental
material was recovered from the Batavia Knoll and Gulden Draak
Ridge indicating that these features are micro-continents rifted from
India during the breakup between Australia and India.
In May-June 2012 Dr Richard Arculus from the Australian National
University led a scientific voyage to the northern Lau Backarc Basin
to investigate magmatism, tectonics and hydrothermal activity. The
northern Lau Basin is a region of rapidly extending and newlyforming
crust, seamed by multiple zones of sea-floor spreading,
rifting and faulting consequent to the clockwise rotation of the
Tonga Arc away from the Fiji-Lau Ridge. The demise of the former
Vitiaz Arc has led to the establishment of a new Australian-Pacific
plate boundary that wraps around the north end of Fiji, and
R/V Investigator in progress
(Acknowl. www.csiro.au)
connects with the Tonga Trench via a set of ridges (e.g. Futuna
Spreading Centre, Northwest Lau Spreading Centre), rifts (e.g.
Rochambeau Rifts), transform faults and extension zones. The
voyage explored these tectonic elements and the accompanying
magmatism and hydrothermal activity.
In Oct-Nov 2012, Dr Maria Seton of the University of Sydney will
lead a voyage to the eastern Coral Sea. The main objectives of this
voyage are to investigate (i) the nature of the crust
(continental/volcanic/oceanic) underlying Rennell Island, East
Rennell Island Ridge, South Rennell Fracture Zone and
d’Entrecasteaux Zone, and (ii) the age and structure of the Santa
Cruz/Torres and d’Entrecasteaux Basins. We will also explore
whether the basins formed in a back-arc setting related to
Cretaceous or Eocene subduction or whether they preserve a piece
of oceanic crust from the Panthalassa Ocean, and (iii) the extension
of the Lord Howe hotspot trail into the eastern Coral Sea, north of
the Bellona Plateau.
Dr Maria Seton from the University of Sydney is the Chair of the
new Back and Island Arc (BI-ARC) Working Group. The working
group hopes to foster a holistic approach to address fundamental
questions about intra-oceanic arc and backarc basin processes by
examining the long-term and short-term evolutionary cycles using
geochemical, hydrothermal, biological, tectonic and subduction
dynamics approaches. In addition, we aim to bridge the gap between
geologists who study onshore, accreted island-arc and back-arc
systems and marine geoscientists who study in-situ backarc systems.
The working group seeks to bring together experts from both the
observational and modeling communities to facilitate the linkage
between surface processes and the deep earth.
INTERRIDGE NEWS 35 VOL.21, 2012