f Geometrical aspects of communication across faults in sand/shale sequences

Subsurface faults are important with respect to the distribution of hydrocarbons in reservoirs. They may serve as pathways to hydrocarbon migration, or become barriers preventing migration and acting to compartmentalize a reservoir. Being able to understand and analyse the conditions around fault planes and zones is therefore crucial if one wants to be able to predict the character of faults and thereby the type of migration control that a fault might be responsible for. Whether hydrocarbons are trapped against a fault or can migrate along/across the fault is controlled by the characteristics of 1) the material juxtaposed across the fault and 2) the material present in the fault zone (Smith, 1966 & 1980). To obtain a better understanding of the role of faults in the subsurface with regard to hydrocarbon migration and entrapment one approach is to analyse the problem numerically. Such an approach has been applied in the following.