Title: The kinematics of fault systems in offshore Ireland – implications for fault related trapping and leakage
Researchers: Dr Muhammad Mudasar Saqab and Dr Conrad Childs
The Irish offshore basins provide an opportunity to develop models of basin and fault system processes and evolution. The wide range of extensional strains experienced by Irish offshore basins, from the low strain Slyne and Erris basins to the very high strains associated with for example, the hyperextended Rockall Basin provide the opportunity to study changes in the geometry and kinematics of fault systems with increasing strain. In particular, the ~200 km long Porcupine Basin demonstrates a progressive southward widening and increase in extension factor, to values of ~6, at its southern limit (White et al., 1992). The particular aspects that will be studied include progressive changes in fault connectivity, the extent of the area of active faulting and the degree to which fault systems become polarised into one fault dip direction as strain increases. The output from the project will provide the regional structural perspective for other parts of the iCRAG initiative in particular providing the structural backdrop for sedimentological and basin/ hydrocarbon migration modelling studies. The aim of this project is to provide a comprehensive synthesis of the structural and kinematic evolution of Ireland’s offshore basins. Of particular importance will be the controls exerted by basement structure on rift-related fault systems and the reactivation and inversion of faults in the different basinal settings. This element will provide the structural backdrop for detailed analysis of the fault systems bounding several of the Irish offshore basins to be conducted in this and related projects. The focus, however, will be on those aspects of the evolution of fault systems relevant to hydrocarbon distribution in the Irish offshore namely, fault-controlled hydrocarbon migration and trapping, and top seal integrity and up-fault flow into post-rift stratigraphic traps.
The key project topics are:
1. Fault system evolution
2. Fault reactivation and trap integrity
3. Basement controls on fault system geometry and kinematics
4. Fluid flow along faults