Understanding the Effects of Igneous Sill Complexes On Potential Oil Producing Basins

Nick Schofield
Earth Sciences, School of Geography, Earth and Enviromental Science, University of Birmingham, Birmingham, Uk; [email protected]

Many sedimentary basins worldwide, such as the North East Rockall and Faroe-Shetland basins (North Atlantic Margin) and Parana basin (Brazil) contain extensive and voluminous networks of subvolcanic intrusions. These areas are becoming sites of increasing interest for the petroleum industry, as they represent areas of possible untapped future resources. The direct implication for hydrocarbon exploration is that laterally extensive sheets of intruded magma can either significantly diminish the hydrocarbon potential of a region, or act to increase it (e.g. the Neuquen basin, Argentina). The sheets can also act as unconventional traps to both oil and gas, however despite the advances sub-basalt imaging in recent times, which has yielded a wealth of data regarding the geometry and architecture of sub volcanic intrusions, understanding the mechanism of their emplacement and associated structures is still poorly understood. Field based studies of similar intrusive systems can potentially gain insights into these problems at a scale and level of detail unattainable with seismic data alone. In particular the dynamic structural evolution of the intrusion and its relationship to host sediment mechanical properties can be better understood. Ongoing research is focusing on the effects of igneous intrusion on surrounding host rocks and the geological constraints which control this. By better understanding field relationships in detail, seismic interpretation of buried offshore volcanic terrane's can be better informed.

AAPG Search and Discovery Article #90083 © 2008 AAPG Foundation Grants in Aid