基于共接收点道集波形相似度的槽波到时估计方法

Estimation method on arrival time of in-seam wave based on similarity of wave-forms in common receiver gather

为解决井下透射槽波数据中接收点子波差异影响槽波到时估计准确度的问题,分析了接收点子波差异的成因,提出了基于共接收点道集波形相似度的槽波到时估计方法,利用接收点子波放大同一接收点上槽波相似性的特点,在共接收点道集上计算各道与其他道的互相关系数,依据波形相似度估计各道的槽波到时。实际探测结果表明:共接收点道集的相邻道之间槽波相似度高,估计出的槽波到时能够准确反映断层引起的槽波速度异常,由此获得的速度层析成像结果中,速度异常区与实际断层位置基本一致。

To accurately detect arrival times of transmitted in-seam waves which are damaged by wavelets of receivers,we analyzed the causes of differences of receiver wavelets,and propose a method to detect arrival time based on similarity of wave-forms in common receiver point gather. The method take advantage of the ability of receiver wavelet which can promote the similarity of wave-forms of same receivers,and compute the cross-correlation coefficient between every trace with other traces,and estimate arrival time of in-seam wave according to the similarity of wave-forms. Results of actual applications showed that in-seam waves in common receiver gather have great similarity to adjacent traces,and the estimated arrival times can show the irregularity of in-seam wave caused by faults. On the tomography computed using estimated arrival times,anomalous velocity regions are in accordance with actual faults.