Research On The Coherence Analysis Weighted By Direction Filtering And Its Application To Fracture Detection

The development of fractures often affects the distribution of hydrocarbon reservoirs and plays a decisive role in dense rocks. The research on seismic identification and prediction of fractured reservoir at home and abroad has been conducted for decades. Although this issue has been studied from many aspects, because of the complex relationship and conflict between the contributing factor with scale of fractures and seismic response characteristics with resolution, the seismic detection technology of fracture zone is still in continuous improvement and continuous development phases.In this paper, the fracture detection and prediction is researched which mainly caused by tectonic deformation as the controlling factors of the crack. First, by studying the causes and distribution of this type of fracture and the concept of fracture zone which was put forward by domestic and abroad scholars, I apply the regional stress analysis and well stress analysis and use direction weighted filtering based on coherent attributions to highlight the direction of fracture zone. Then I make system analysis by utilizing the results of this method and many other attributes, do fusion display, and compare the advantages and disadvantages and range of application of each method. Combining with seismic data, I summarize a practical process which is based on direction weighted coherent attributions.I put the approach into reservoir prediction with dolomite fractures in Fengcheng-Xiazijie in northwest edge of Xinjiang Oilfield, and achieved good results. Form the point of the effect of practical application, I think the detecting techniques which is based on direction weighted coherent attributions are more reliable than the traditional coherent and other attributes. It has better effect of detecting the fractures which caused by structure associated with fault.