Continuous seismic transect between the New Hebrides Arc and the Eastern Australian Margin: FAUST (French Australian Seismic Transect) program

Within the framework of the joint FAUST (French Australian Seismic Transect ) program, the Australian research vessel Rig-Seismic recorded a series of multichannel seismic profiles between the New Hebrides Are and the Australi an Margin. The very high quality of these profiles allows the examination o f the continental or oceanic basement over the whole area surveyed. In basi ns beneath the eastern margin of the northern Lord Howe Rise and the New Ca ledonia Basin, where the crust is thinner, the Moho discontinuity is presen t at about 8.5 seconds two-way time (TWT) (about 12-13 km) on the profiles processed onboard. The data collected suggest that the sedimentary section within the basins includes syn-rift Cretaceous sediments that are nat yet d efinitively identified. The Upper Eocene-Middle Oligocene subduction of the Australian plate beneath the Pacific plate is highlighted by thrust faults concentrated along the Lord Howe, Norfolk and Fairway Ridges. This episode probably corresponds to the period of convergent tectonism associated with the Upper Eocene obduction of the New Caledonian ophiolites. ((C) Academie des sciences / Elsevier, Paris.).