多层裂缝介质转换横波分裂分析技术及应用

Technique and Application of Converted-Wave Splitting for Multi-Layer Fracture Media

基于横波分裂理论,实现了一种利用宽方位转换波的径向和横向分量求取能量比的转换横波分裂分析方法。在此基础上,实现了多层裂缝介质的层剥离横波分裂分析技术。首先,利用能量比法求出第一层裂缝介质的方位角,快、慢波时差等裂缝参数;然后应用慢波数据进行慢波时差补偿;最后将快波和补偿后的慢波旋转回原来的径向和横向分量。将第一层裂缝介质转换为各向同性介质后,依此类推,进行以下多层各向异性介质的横波分裂分析,得到各层的裂缝参数。该技术已用于川西的裂缝预测,取得了较好的效果。

Based on S-wave splitting theory, this paper presents a converted-wave splitting analysis method for getting energy ratio using radial and transverse components of wide-azimuth converted-wave data, and proposed the layer stripping S-wave splitting technique for multi-layer fracture media. Firstly, the energy ratio method is used to obtain the azimuth and time delay of the first layer fracture medium. Then, the time delay is applied to compensation of slow-wave time delay. Lastly, the fast-wave and compensated slow-wave are rotated back to original radial and transverse components. After the first fracture medium is converted into isotropic medium, the fractural parameters are obtained by lower multi-layer anisotropie media analysis. The technique has been applied to prediction of stratigraphic fractures in western Sichuan and good results have been acquired.