Fracture-induced Seismic Anisotropy When Whearing Is Involved during Production from Fractured Reservoirs

摘要

The surface roughness of joints or fractures, helped by sufficient confinement-enhanced rock strength, may be responsible for maintaining permeability despite high confining pressures, corresponding to petroleum reservoir depths of several kilometres. Nevertheless, measurements in deeper wells reported by Zoback and colleagues, but in stronger crystalline rocks, do not show conducting joints parallel to the 'classic' direction σ_(H max·) Furthermore, several reservoir cases reviewed in Barton 2006, in fact show 20° to 30° rotations of the polarization axes of qS_1 and qS_2, relative to the borehole break-out interpreted σ_(H max) direction.