具有截断误差校正的广角反射NMO方法

NMO method of wide angle reflection with truncation error correction

许多新的广角反射NMO校正方法采用了Taner展开式的截断式,但截断误差的存在,使得这些方法的应 用效果受到了影响。从Taner的反射波时距曲线方程入手,提出了具有截断误差校正的广角NMO校正方法。 该方法将截断误差分解成2部分来消除:①采用Taner的4阶方程,并在4阶项上加上一个权系数,使拟合曲线 最佳逼近反射波旅行时,权系数采用寻优方法求取;②利用偏移距与深度之比较小的记录道生成模型道,以求取 的地震道与模型道之间互相关系数最大时的延迟量为剩余截断误差,进行校正。理论模型与实际资料试算结果 表明,具有截断误差校正的广角反射NMO校正方法可以改善同相轴质量,提高叠加效果。

Many methods on wide-angle reflection NMO correction is used to truncation of Taner expansion. The application effects on these methods are affected because of truncation error. Start with Taner reflection time curve equation, present the wide angle NMO correction method on truncation error correction. The method is eliminate truncation error divide into two parts:① Using to Taner fourth-order equation, adding a weight coefficient to fourth-order i-tem,extract the weight coefficient to best appropriate way; ② Making recording trace to model trace smaller offset distance/depth, with delay quantity is residual truncation error to correction which cross-correlation coefficient is most between the seismic trace and model trace. According to the theoretical model and factual data calculation result, this method reforms the quality for phase axis, and improve the stacking effect.