2610588 Volumetric Fault Imaging based on Seismic Geometry Analysis

Computer-aided fault imaging and interpretation is a fundamental tool for subsurface structure characterization and modeling, and the existing methods are primarily based on seismic discontinuity analysis (e.g., coherence and semblance) that evaluates the lateral variation of waveform and/or amplitude. However, such attributes have a limited resolution on subtle faults without apparent displacements in seismic images, which correspondingly decreases the accuracy of fault detection and interpretation. This study presents a new method for volumetric fault imaging based on seismic geometry analysis, consisting of two components. First, the curvature and flexure analysis is performed for fault detection from the perspective of evaluating the changes in the geometry of seismic reflectors, which helps highlight both the major faults and the subtle ones. Then an isolation operator is performed for differentiating the faults from the non-fault features observed in the curvature/flexure volumes, which leads to a fault volume with each lineament representing a potential fault. The added value of the proposed method is verified through applications to two 3D seismic volumes from the offshore New Zealand and the Netherlands North Sea. The results not only clearly depict the faulting complexities with varying sizes and orientations, but also indicates its great potential for improving the semiautomatic/automatic fault extraction from 3D seismic data.