Basin development and petroleum prospectivity of the Rockall and Hatton region

Abstract

Abstract The Rockall region, offshore west of Ireland, contains a number of large, virtually unexplored, frontier sedimentary basins: Rockall Trough, Hatton Basin and Hatton Continental Margin. It is suggested that the sedimentary section, up to 6 km thick, is of Late Palaeozoic to Tertiary age. Normal incidence reflection seismic data from the region are typically of poor quality owing to the effects of shallow Tertiary sills. Recent wide-angle reflection seismic profiles have helped to resolve the basin geometry and structural setting. Backstripping (reverse modelling) and forward modelling of the wide-angle model are consistent with development in a complex multi-phase rift setting. Rift events are suggested in the Jurassic and Cretaceous, and possibly locally during the Permo-Triassic. The variation in structural style across the region is interpreted as resulting from the interplay of intraplate stresses, magmatic underplating, thermal doming and thermal subsidence adjacent to the continent/ocean margin, and seafloor spreading dynamics in the region to the west. The basins are predicted to contain a range of petroleum plays. Structural, stratigraphic and combination traps are indicated from a range of data. Reservoirs are predicted at several levels, with source rocks in the Jurassic and lowermost Cretaceous.