Characterization of fluid flow anisotropy in a carbonate reservoir using AVAz inversion of wide-azimuth seismic data

Rock fractures are of great practical importance to petroleum reservoir engineering because they provide pathways for fluid flow, especially in reservoirs with low matrix permeability, where they constitute the primary flow conduits. An example is the Midale reservoir, SE Saskatchewan, Canada. In such reservoirs, understanding the spatial distribution of natural fracture networks is key to optimizing production. Fortunately, the presence of fractures can be inferred from variations in reflection amplitude as a function of azimuth and incidence angle. This paper presents the application of a method for constructing a geologically realistic discrete fracture network (DFN), constrained by seismic amplitude variation with offset and azimuth (AVAz) data. The DFN realization is upscaled to compute the anisotropic permeability tensor, which is then compared with waterflood results.