Modeling of Fault Reactivation and Fault Slip in Producing Gas Fields

are generally based on either empirical relations which link compaction strain and seismic release or simple relations between available fault area and seismic moment release. Physics based understanding of the impact of stress evolution on faults due to production is needed to reduce uncertainties and support the basic assumptions in seismological models and hazard assessments. Geomechanical analysis shows fault offsets, reservoir geometry and differential compaction play an important role in production induced fault reactivation. These effects are currently not accounted for in the hazard analyses. Both simplified 2D and full field 3D geomechanical models can be used to model the onset of reactivation – and identify faults which are prone to be reactivated. To get more insight into the seismic response of the faults, i.e. the extent of the rupture area and slip displacements, more advanced friction laws need to be incorporated.