利用S波源VSP四分量检测裂缝

Fracture detecting by four-component VSP data from S-wave source.

本文利用 S波源 VSP四分量资料进行裂缝检测。首先利用非零偏 P波对 S波源进行定位 ,再利用 Alford旋转分离出快、慢横波 ,并求出快、慢波时差 ;最后用快、慢波时差计算各向异性因子以及裂缝密度。处理结果与钻井资料对比证明 ,S波源 VSP四分量资料是研究岩体应力和裂缝结构的有力工具 。

The paper presented a method for detecting fracture by using four component VSP data from S wave source. It conducts location of S wave source using nonzero offset P wave VSP data first, then the S wave data has been separated into fast and slow S waves by Alford rotation method and resulted time difference between fast and slow waves; finally, anisotropic factors and fracture density has been calculated from time difference of fast and slow waves. Comparing processed results with drilling data shows that four component VSP data from S wave source is a powerful tool for studying rock stress and fracture structure, also is effective method carrying out surveying fracture orientation and describing fractured reservoir.