Abstract: Automatic identification of discontinuous geological bodies such as faults and angle unconformity is of significance in seismic structural interpretation, which in the seismic profile appears as the discontinuity of reflection events. The application scope of the conventional seismic data discontinuity identification method is limited due to the fact that its parameter setting relies on human experiences, which could easily results in an improper identification. Therefore, in this paper, coherence is introduced into seismic data processing as a new discontinuity identification parameter. Firstly, the coherence was calculated by the Facet model gradient operator, which is high positioning accurate and easy to be expanded. Secondly, we applied a threshold on the coherence data. Finally, the corrosion, expansion and thinning algorithm in mathematical morphology were used for further processing to realize the automatic identification of the seismic data discontinuity information. Through the synthetic and field seismic data tests, and the comparison with C₃ coherent algorithms, as well as variance algorithm, we can demonstrate that the proposed method can be used as a powerful tool for the discontinuity identification in formations, with a higher stability and identification ability in seismic data discontinuity lineation.

Key words: coherence, Facet modelgradient operator, discontinuity identification, seismic data