Fracture Characterization from Scattered Energy: A Case Study

Abstract

We use 3D surface seismic data to determine the presence and the preferred orientation of fracture corridors in a field. The Scattering Index method is proving to be a robust tool for detecting and mapping fracture corridors. Fracture corridors largely control permeability and fluid flow in some fractured reservoirs. To apply the Scattering Index method, we compute the scattering transfer functions from the reservoir interval using prestack migrated data collected in four azimuth sectors. By measuring the azimuthal differences in the amount of scattering, we obtain maps of density of fracture corridors and their orientation across the survey area. We use geostatistical filtering to improve the spatial correlation of scattering index maps. The distribution and orientation of the final fracture corridors are interpreted considering the structure, fault network, and stress information. In the field, we observe several regions of high fracturing near the anticline’s crest and on its steepest slopes, on the southwest flank. Around well locations, fractures are oriented to the NW and NNW, which agrees with estimates of maximum stress direction from well data.