高密点地震资料面波压制的自适应波束方法

Self-adaptive beam method for suppressing ground roll in high-density seismic data

在单点采集的地震记录上,面波能量非常强,有效信号淹没于其中,地震资料的信噪比较低。在常规地震资料处理中,通常采用相位匹配法和高通滤波法对面波进行压制,但存在面波去除不干净或损害有效低频反射波等问题,即使是F-K滤波和小波变换面波压制等改进方法也或多或少地存在同样的问题。为解决这一问题,提出了自适应波束面波压制方法。该方法利用有效反射波和面波在视速度上的差异,通过设计合理的代价函数,不断优化滤波器的权系数,可以在面波区有效衰减面波能量,保全有效反射波。对新疆亚肯北地区某测线高密度单点采集资料,利用自适应波束方法进行面波压制,取得了很好的效果,在去除面波的同时有效信号得到了保护,资料的信噪比得到了提高。

In original single-sensor seismic data.the ground roll interference is very strong,which often conceals the effective signal;at the same time,the S/N of original data is very low.In conventional seismic data processing,phase matching method and high-pass filtering method are usually adopted.But after using these methods, ground-roll still exists or low-frequency effective wave is damaged, even by using f-k filtering,wavelet transformation filtering,etc. aiming at the problem.We proposed self-adaptive beam method for suppressing ground roll.The method uses the difference of apparent velocity between effective reflection and ground roll,by designing reasonable cost function and optimizing weighted coefficient of filter,to effectively attenuate ground roll energy and preserve effective reflection.We use the method to suppress ground roll of high-density single-sensor data from Yakenbei area,Xinjiang.Good results have been achieved,the ground roll was removed,meanwhile,the effective signal was preserved,and the S/N was enhanced.