Multi-trace Curvature and Rotation Attributes- Application to Fractured and Hydrothermally Altered Reservoirs

Sullivan, Charlotte and Marfurt, Kurt

Allied Geophysical Labs, University of Houston

Modern multi-trace geometric seismic attributes include the well-known coherence technology, and new estimates of curvature and dip rotation. These attributes, which are generated from conventional P-wave 3-D seismic volumes, are especially useful in imaging rugose surfaces, and in identifying fracture zones, joint systems, small faults, and other features previously considered to be subseismic. In contrast to conventional attribute analysis, we generate a complete 3-D volume for each attribute, thereby eliminating interpretation errors involved in picking irregular surfaces that are so common in faulted and karsted terrains. The resulting multi-trace attribute volumes are loaded and interpreted within standard interpretation software packages. The attributes can be viewed in time slices, vertical sections and in extractions along picked horizons. Of special interest for operators in the Appalachian basin is the potential of these attributes to: 1) predict stress regimes and most likely azimuth of open fracture direction for any level within a 3-D survey, 2) map and quantify lineament density and azimuth through time, and 3) predict most likely areas of localization of fluid flow along faults that have a wrench component. We illustrate the calibration and application of these robust attributes to fractured, karsted and hydrothermally altered reservoirs in the Appalachian and other basins.