Joint Australian-French Research in the Tasman Sea

IAUSTRALIAN NEWS

Joint Australian-French Research In The Tasman Sea

even Geoscience Australia (GA) officers recently participated in a joint French SAustralian geological research survey in the Tasman Sea designed to study two large sed imentary bas ins, the Capel and Faust.

The survey took p lace from February 12th - 26th between New Ca ledonia (Noumea) and Sydney using the French research vessel Marion Dufresne, the March edition of Geoscience Research Vessel Marion Dufresne. Austra lia News reported. Jim Colwell of GA was the ch ief scientist 0 11 board. Pa rticipa nts bathymetry data along the lower continental came from Austral ian and French institutes, slope of eastern Australia from the Queensland/ primaril y from GA, the Fre nch Institute for NSW border to Sydney. Seven giant (Calypso) Marine Research (IFREMER) and the French piston cores (up to 36 m in length), five dredge Institute for Research and Development (IRD). hau ls and four heat flow stations were taken in Austral ia's maritime jurisdiction. The research was designed to investigate unusual geophysical features in the Faust and Issues being addressed by this work include Capel sedimentary basins and to collect swath the natu re of diapirs (relatively mobile masses that intrude into pre-existing rocks eg. salt domes) and a se ism ic reflector cal led a bottom simulating reflector, which might represent gas hydrate (frozen methane gas). Labelling one of the giant (Calypso) piston cores prior to it being cut into 1.5 m long sections for A high thermal gradient in some places indicates the escape of hot f luids from deep in the splitting and sampling. underlying sediments. A ll these phenomena are of scientific interest and bear on the long under the auspices of the 'University of the Sea', term petroleum potential of the reg ion. for oceanograph ic research tra ining.

Basement rocks were also dredged from ridges During their time at sea, students representing on both sides of the bas in. The dredging has seven countri es (F iji, So lomon Is lands, Indonesia, shown that the eastern ridge is gran ite, resu lting Sri Lanka, Republ ic of Korea, New Zea land and Sampling one of the split core sections. in the discovery that the origins of the ridges are Australia) received va luable hands 0 11 ocean Geoscience Australia's Nadege Roi/et (left), continental rather than ocean ic. In addition to science experience. • and Emma Grosjean (right ) with one of the the scientific researc h activities, 19 students and University of the Sea students. three marine scientists were aboard the vesse l

Dredge containing rocks being brought back on board the Marion Dufresne .