误差均值法实现广角反射NMO校正

NMO correction of wide-angle reflection by mean errors value method.

从具有截断误差校正的广角反射NMO校正公式出发,分析了引起动校误差的原因,并指出由于误差的存在而进行的剩余误差估算方法在实现过程中存在的问题。在此基础上,根据泰勒四阶截断方程与六阶截断方程分别位于实际反射波旅行时曲线的上、下方,以及由一条曲线向另一条曲线逼近时,相似性较高的两曲线逼近程度也较高这样两个客观事实,采用使最佳六阶方程逼近与四阶截断方程有相同误差且位于实际反射波旅行时下方的曲线,并求取六阶方程与四阶截断方程的均值,以消除应用泰勒截断方程存在的截断误差影响。该方法可以精确地逼近反射波旅行时,且避免了剩余截断误差的估算。文中利用理论模型及实际资料对该方法进行了检验。

Starting from the formula of NMO correction of wide-angle reflection having the correction of truncation errors, the paper analyzed the causes of NMO errors and pointed out existed problems during the process of evaluating the residual errors. On that basis, according to the two objective realities that the 4th-order Taylor truncation equation and 6th-order Taylor truncation equation are situated above and bellow the true travel-time curve of reflections separately and that the two curves having higher similarity closely approaches each other when one curve approaches to the other, using optimum curve that has similar errors when 6th-order equation approaches to the 4th-order equation and is situated bellow the true travel-time of reflections and computing the mean values both for 4th-order equation and 6th-order equation can eliminate the influence of truncation errors existed in application of Taylor truncation equation. The method can accurately approach the travel-time of reflections and avoid the evaluation of residual truncation errors. The paper tested the method by using theoretical models and practical data.