The European Margin Between Ireland and the Iceland Basin

During the last six years the Institute of Geophysics, University of Hamburg (IFG) has been engaged in several wide-angle reflection and refraction seismic (WARRS) studies of the European margin west of Ireland and the British Isles (fig. 1). In particular, the cooperation between the German and the Irish through the agreement between the IFG and DIASI has given us the opportunity to investigate the crustal structure and basin development along a 1000 kill line between the west coast of Ireland and the Iceland Basin. Four 'R/V Valdivia' cruises were required for this study which produced more than 200 Ocean Bottom Seismograph (OBS) positions. Our main aims were to resolve the problems of the oceanisation of the Rockall Trough (Roberts, 1975; Roberts et al., 1981; Joppen & White, 1990), to test the concept of 'underplating' at the continent-ocean transition from the Hatton-Rockall Basin to the oceanic crust of the Iceland Basin (White & McKenzie, 1989; Morgan et al., 1989) and to resolve the velocity structure of the 'dipping reflectors' at the edge of the Hatton-Rockall Basin (White et al., 1987).