The eastern and western tips of Manus Basin (Papua, New Guinea) explored by submersible; MANAUTE cruise.

The objective of the Manaute cruise of the R.V. L'Atalante with the submers ible Nautile was the in situ study of accretion processes, magmatic activit y and hydrothermalism in the Manus Basin. Twelve dives and 18 dredges, focu sing on the eastern and western tips of the basin, allowed us to demonstrat e that in the eastern part of the basin the oceanic accretion is reduced to two axes propagating between Djaul and Weitin FZ. However the magmatic and hydrothermal activity is widely spread along the axes but also on volcanoe s and ridges aligned on a N110 oblique direction. In the western part of Ma n-us basin the oceanic accretion is located along two axes propagating rapi dly to the southwest. The magmatic and hydrothermal activities are variable and diffuse over the whole area. The effect of the subduction of the Austr alian Plate in the New Britain Trench is evident throughout the basin. (C) 2000 Academie des sciences/Editions scientifiques et medicales Elsevier SAS .