New Methods for Extracting and Constructing Fault Surfaces from 3D Seismic Data

Introduction The description of a fault model includes the fault surfaces and associated tip lines, the fault network geometry, and the displacement geometry of faults. Fault surfaces are usually observed from seismic discontinuities, which include reflector breaks, flexures, and amplitude changes. These discontinuities can often have a regular appearance that corresponds to fault geometries found in rock analogues. Coherency-type cubes, hereafter referred to as discontinuity cubes, are often used to highlight faults in structurally complex areas. In despite of this, methods for automatic tracking of fault surfaces have often failed because of the ambiguous appearance of these discontinuities. Extracted objects from raw discontinuity cubes will usually not appear like fault surfaces and need heavy editing before they are put into a fault model. As a result, fault interpretation is generally performed by interpretations on seismic sections with no use of automatic extraction of seismic discontinuities.