SVD滤波法在直达波和折射波衰减处理中的应用

在地震资料的处理过程中，需要消除原始资料中直达波和折射波等能量很强的线性干扰波的影响，但常规方法在切除线性干扰波的同时也切除了来自浅层的反射能量，从而失去了反映浅层地质构造的信息。应用SVD（奇异值分解）滤波法不仅可以达到衰减具有线性特征的直达波和折射波能量的目的，又能突出具有非线性特征的浅层一次反射能量，可以避免丢失浅层有效反射信息。理论模型的试算和对实际资料的处理结果表明，应用SVD滤波法处理地震资料能取得较好的效果。图3参6

Application of SVD filtering in the processing of decaying direct wave and refracted wave

In the processing of seismic data, the quality of the processed seismic data can be improved if the influence of disturbed waves with strong energy in the crude data such as direct-wave and refracted-wave could be eliminated. The common cutting method would lose the information reflecting shallow geologic structure since that the reflected waves from the shallow layers are cut down together with the disturb waves. The SVD filtering method will be able to suppress the direct-wave and refracted-wave with linear characteristics and to strengthen the primary shallow seismic reflection energy with non-linear characteristics, and the useful shallow seismic reflection information would not be lost. The results of theoretical model and actual data processing suggest that the method is practically efficient.