High-Precision Iterative VSP Wavefield Separation

Abstract

Conventional vertical seismic profiling (VSP) wavefield separation method (CSM) focuses on the wavefield separation result, not the residual. Usually, it cannot obtain desirable high-precision results. Iterative zero-offset VSP (ZVSP). However, IZSM only can be used for ZVSP data, which limits its application. The scalar wavefield separation algorithm used in IZSM is based on the SVD filtering, which limits its precision. The objective function threshold of IZSM is varied with the input ZVSP data, which limits its result precision and efficiency. To improve the wavefield separation precision and efficiency, we propose a high-precision iterative VSP wavefield separation method (HISM). HISM is suitable for both ZVSP and offset VSP (OVSP) data, and also applicable for any possible scalar wavefield separation algorithm The objective function threshold of HISM can be a fixed number. Therefore, HISM can obtain high precision and efficiency results. Actual ZVSP and OVSP data application demonstrates the performance of HISM.