A new method for wide-angle reflection normal moveout correction with high precision
Liu Xiao1, Gao Ergen1, Ding Liang1, He Yingchun2, Xue Yuying2, Liu Wenjing3
1. Department of Earthquake Science, Institute of Disaster Prevention, Sanhe, Hebei 065201, China;
2. BGP Geological Research Center, CNPC, Zhuozhou, Hebei 072751, China;
3. School of Petroleum Geophysical Exploration, BGP Inc., CNPC, Zhuozhou, Hebei 072751, China
Abstract：First based on traveltime-to-distance equation of horizontal multilayered media, we differentiate all-order derivatives of travel time t with respect to offset x near the shot point, and substitute the result into truncated Taylor's expansion for travel time t. A six order polynomial equation near the shot point is obtained. Then, we get the approximate formula of wide-angle reflection normal moveout correction under long-offset conditions by analyzing characteristics of relational equations. Finally, we discuss theoretically application conditions of the six order polynomial and the approximate formula. Based on our numerical simulations, the proposed normal moveout correction method can control the relative error rate of traveltime within 1% when offset is more than 4 times of depth, and it can stretch seismic events at near and far offsets. Therefore, this method may be used as a high precision method for wide-angle reflection normal moveout correction.
刘骁, 高尔根, 丁亮, 何迎春, 薛玉英, 刘文静. 一种新的高精度广角反射动校正方法[J]. 石油地球物理勘探, 2016, 51(5): 894-900.
Liu Xiao, Gao Ergen, Ding Liang, He Yingchun, Xue Yuying, Liu Wenjing. A new method for wide-angle reflection normal moveout correction with high precision. OGP, 2016, 51(5): 894-900.
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