Seismic geological structure characterization using a high-order spectrum-coherence attribute

Characterization of seismic geological structures, such as describing fluvial channels and geological faults, is significant for seismic reservoir prediction. The coherence algorithm is one of the widely used techniques for describing discontinuous seismic geological structures. However, precise coherence attributes between adjacent seismic traces are difficult to compute due to the non-stationary and non-Gaussian property of seismic data. To describe seismic geological structures accurately, we define a high-order spectrum-coherence (HOSC) attribute. We first develop a time-frequency (TF) analysis method to compute a constant-frequency seismic volume with high TF resolution, i.e. the second-order synchrosqueezing wave packet transform (SSWPT). Then, we develop a coherence approach by combining the mutual information calculation (MI) and coherence algorithm based on the eigenvalue computation (C3). To improve computational efficiency, we adopt the information divergence instead of the eigenvalue calculation of the C3 based algorithms. By applying the proposed coherence algorithm to constant-frequency seismic volumes, we obtain the HOSC attribute. To testify the validity of the proposed workflow, we evaluate the HOSC attribute using synthetic data. After applying the proposed workflow to 3D real seismic data located in eastern China, the HOSC attribute characterizes seismic geological discontinuities and subtle features clearly and accurately, such as fluvial channels and subtle faults.