联合纵波确定转换波接收点大的静校正量

Estimating C-wave receiver large statics associated with p-wave imaging

在转换波地震勘探数据处理中,接收点的横波静校正一直是较难解决的问题.因为横波速度基本不受潜水面的影响,横波低速带厚且不均匀,速度又比较低,通常会造成转换波接收点的横波静校正量大且横向变化剧烈,与纵波静校正没有直接相关性.针对这种情况,我们采用改进的纵波构造时间控制方法求取转换波接收点的静校正,在转换波的共接收点叠加剖面上追踪拾取多组同相轴,联合纵波对应层位的地下构造时间确定接收点大的横波静校正量.通过不同的时移将几个相邻的层位合成一个反射层位,解决同相轴不能连续追踪的难题,同时利用浅、中和深层多组层位对一个接收点的静校正量求其平均,降低拾取误差对静校正量的影响,兼顾地下浅、中和深层的静校正效果.实际数据处理结果表明,该静校正方法能稳定的解决转换波静校正问题,取得了较好的应用效果.

In converted wave seismic data processing an important and hard step is the evaluation of the receiver statics for the horizontal components. The receiver statics of converted-wave is frequently large, lateral variability severely and noncorrelation with the Pwave static, because the S-wave velocity is almost unaffected by water-table and generally very low, and S-wave associated with thick belt, laterally varying in the near surface. Considering that, here we adopt an improved method which is constrained by subsurface structure time of matching events of P-wave to estimate the large receiver statics of converted wave, by Tracking and picking several time events on the common receiver stack section. The difficult problem that the event can not be continuous tracking is solved by picking adjacent event with a time shift. While taking advantage of average the receiver statics of shallow, medium and deep events to reduce picking error and obtain effect of overall. The real application indicates this method can stably evaluate receiver statics of converted wave with encouraging results.