Abstract:
Concealed faults, which feature low grades, small throws, and small event distortions on seismic sections, are important to oil and gas exploration assessment, waterflood development, hydraulic fracturing, and gas storage safety. The concealed faults exhibiting differential extension associated with newly discovered intersected structural traps have garnered considerable attention. However, how to identify such faults with unclear genesis is a big challenge. This study focuses on Block X in central Bohai Bay Basin. Based on the geometric and kinematic characteristics of main faults and known concealed faults derived from seismic and well data, concealed faults are believed to commonly develop at the intersections between the segments of a main fault. A method known as “integrated geologic-geophysical interpretation” is proposed for predicting extensional concealed faults. This approach employs the “throw-distance curve” to pinpoint concealed faults, seismic attribute maps to indicate their strikes, and seismic profiles to verify their presence. The successful application of this method to Block X is referential to the identification of concealed faults with differential extension in similar areas.