Coherence calculation with adaptive windows and its application
Yang Baojun1,2, Yang Changchun1,2, Chen Yuhong2,3, Li Xin1,2, Cui Yongfu4
1. Institute of Geology and Geophysics,Chinese Academy of Sciences,Beijing 100029,China;
2. Key Laboratory of Petroleum Resource Research,Chinese Academy of Sciences,Beijing 100029,China;
3. Lanzhou Oil and Gas Resource Research Center,Institute of Geology and Geophysics,Chinese Academy of Sciences,Lanzhou,Gansu 730000,China;
4. Research Institute of Exploration and Development,Tarim Oilfield Company,CNPC,Korla,Xinjiang 841000,China
Abstract：Coherence is one of the most important attrib-utes to be used to identify fault form，channel sandbody distribution and carbonate fracture develop-ment .At present the time window is fixed at cen-ter point during coherence calculation. This cannotinvolve both the shallow and the deep layers.Itmay cross a few events when analyzing the shallowlayer，but within one event when analyzing thedeep layer(low frequency zone).The coherencenear zero point of events is influenced by randomnoise.In addition, even if the window size is ap-propriate，the first break points or the end pointsof the waveform are easily affected by the adjacentwaveform，and it is difficult to obtain accurate dip，azimuth and coherence values.In order to over-come these challenges，we propose a new ap-proach. First the window is chosen adaptively bythe seismic data waveform.The calculated coher-ence value in the window is taken as the coherencevalue of all the samples in this window.The dipand azimuth of the waveform are estimated by cal-culation of the apparent dip coherence value.Andthe dip and azimuth of the adjacent waveforms arethen merged.Field data tests indicate that this ap-proach obtains better results.
杨葆军, 杨长春, 陈雨红, 李欣, 崔永福. 自适应时窗相干体计算技术及其应用[J]. 石油地球物理勘探, 2013, 48(3): 436-442.
Yang Baojun, Yang Changchun, Chen Yuhong, Li Xin, Cui Yongfu. Coherence calculation with adaptive windows and its application. OGP, 2013, 48(3): 436-442.
