The Detection Of Channel Based On Geological Heterogeneous Directional Coherence Technique

Ancient channel is rich in subsurface water,and sometimes it can be a reservoir containing oil and gas.Therefore,detection of channel is a key goal to seismic exploration.Reservoir always distributes in subsurface with heterogeneous features,which brings great challenge in channel identification.In recent years,several methods are proposed to identify the distribution of channel,of which the most popular method is seismic attribute analysis technique,such as coherence,variance,instantaneous phase and so on.These methods could obtain favorable results in detection of channel.However,when applied to strong heterogeneous area where geological structure is complex,conventional seismic attributes are hard to satisfy.In this paper,a heterogeneous directional coherence method is presented to solve the problem above.From the amplitude slice,the distribution of geological abnormalities can be observed roughly.Therefore,the proposed method just starts with the rich prior information consisted in the original seismic data,and adds the useful information to coherence algorithm for getting a coherence data with higher resolution and richer details about channel.A numerical model,a physical model and a real data are used to test the performance of the algorithm for detecting edges of channel.Compared with conventional seismic attributes,heterogeneous directional correlation method can get a better result about identification of channel.The proposed method not only improves the resolution of channel,but also facilitates the detection of weak or hidden geological abnormalities.In addition,the method can assist in analyzing geological structure and predicating oil and gas more elaborately,thus further determining sweet spots and locating wells more accurately.