地震异常振幅自适应压制

Seismic abnormal amplitude self-adapting inhibition

由于磁带掉磁粉导致地震老资料中存在异常振幅以及叠加剖面中也存在异常振幅。若不对异常振幅进行压制,将造成地震资料纵、横向能量不均匀,导致DMO或偏移划弧,最终影响地震剖面质量。从目前应用的Geo-Cluster地震处理系统看,有几种剔除异常振幅值的方法,但实际处理效果不能令人满意。为此提出一种地震异常振幅自适应压制方法,该方法首先对不同时窗内的平均绝对振幅或均方根振幅进行统计,然后,把各采样点振幅与窗内的平均绝对振幅或均方根振幅比较,计算衰减函数,并应用到对应的采样点上,达到使地震资料纵、横向能量变化均匀的目的,避免DMO、偏移划弧现象的发生。经理论模型及实际资料验证,地震异常振幅自适应压制方法实用性强,对异常振幅处理效果明显。

Due to tape magnetic powder loss, there are abnormal amplitudes in old data, and abnormal amplitudes in stacked sections. If not inhibiting those abnormal amplitudes, they will cause uneven vertical and horizontal energies of seismic data, leading to DMO or arc migration, finally affecting seismic profile quality. In view of current applied Geo-Cluster seismic processing system, there are several abnormal amplitude elimination methods, but the real processing effect is not satisfying. Therefore, a method of seismic abnormal amplitude self-adapting inhibition is brought forward. First, this method conducts statistics of average absolute amplitude or mean square root amplitude in different time windows. Next, it correlates amplitudes of different sampling points with the average absolute amplitude or mean square root amplitude in the window, calculates deamplification functions, and applies them into corresponding sampling points, in order to even the variance of seismic data vertical and horizontal energy, and to avoid DMO and arc migration. Through theoretical model and real data attestation, this method has a good feasibility and obvious effect in abnormal amplitude processing.