Fault and Fracture Corridors – How to Reduce the Structural Uncertainty for Reservoir Management Optimization

Abstract

TX 75083-3836, U.S.A., fax 01-972-952-9435. AbstractThe occurrence of discontinuities such as faults, fractures or fracture corridors in the porous rock matrix usually has a strong impact on fluid flow and needs to be addressed carefully during the life cycle of the reservoirs. The major difficulty in characterizing the hydraulic properties of such systems frequently relates with our ability to integrate all the information in a meaningful way in order to derive the key factors constraining the development, intensity and role of the main fracture type in a given reservoir 1 . When the faults/fracture corridors act as baffles or barriers they may delineate compartments and blocks with differential drainage rates and variations in pore pressure. Where flow takes place in both the matrix and along/across the discontinuities, the flow paths can become very complex and the way the two systems interplay may even change with time or with injected/produced fluids. Likewise, the occurrence of faults identified from seismic or fractures brings some extra complexity to the strategies used for reservoir simulation. Issues like how to characterize the faults at different scales and to perform fault ranking and upscaling may have a strong impact on the way simulation results will match actual reservoir dynamics.

Multiscale Mimetic Solvers for Efficient Streamline Simulation of Fractured Reservoirs

“…Traditional finitedifference simulators were not designed to handle such models efficiently. This is particularly true for fractured reservoirs, which are very difficult to manage and to optimize recovery for; see Bockel-Rebelle et al (2005). About 60% of the world's conventional oil reserves and almost half of its gas reserves are contained in carbonate reservoirs, which tend to be more naturally fractured than sandstone reservoirs.…”