Rapid Screening of Pre-stack Seismic for Hydrocarbon Prospectivity

Pre-stack seismic data is often overlooked until interpretation of the full-stack seismic data is completed and zones of interest are defined. Delayed use and interpretation of pre-stack seismic data is unnecessary and a framework has been developed to perform preliminary screening of large quantities of pre-stack seismic data. The outputs from this framework are geobodies that indicate potential fluid related anomalies and can be used to focus future interpretation. Within the framework seismic angle stacks or angle gathers are transformed through a dynamic intercept-gradient inversion into a minimum energy chi projection volume. This volume is analysed statistically to form an anomaly probability volume that can be used in a 3D connectivity algorithm. The resulting 3D connected anomalies can be filtered based on their ID, pixel connected volume, centroid depth, azimuth of longest axis and number of closing contours. These geobodies can then be visualised and interpreted in 3D. The framework is implemented on a Linux cluster and runs in parallel to enable scalability. The development and application of such techniques is becoming increasingly important as the data size and complexity of seismic volumes increase.