How to Account for Dynamic Fracture Behaviour in Reservoir Simulation

Natural and induced fractures and faults have strong impact on fluid flow in hydrocarbon formations and aquifers, governing flow paths and sweep efficiency. Recent reservoir simulations have shown significant changes in flow characteristics when accounting for dynamic fracture behaviour. These effects may be exploited for production optimization and improved hydrocarbon recovery. Modern fracture modelling techniques integrating seismic and well data are efficient in representation of actual fracture geometry and estimation/up-scaling of fracture properties for reservoir simulation. However, dynamic fracture behaviour has got limited attention so far. Experimental studies have shown that stress changes caused fracture closure and shear deformations. This leads to changes in fracture properties, particularly conductivity. Disregard of dynamic permeability in conventional pressure transient and production analyses motivated studies with focus on characterizing dynamic fractures. As a result new interpretation techniques have been developed to complement a workflow which takes well test, production and core data into account in estimating dynamic fracture impact on permeability in reservoir models. In this paper main stages of the workflow with some examples of a naturally fractured reservoir and prospects to characterize dynamic hydraulic fractures and faults are discussed. Potential areas for application of dynamic fracture characterization and simulation are considered.