地层横波慢度信息可用于评价井眼稳定性、监测泥浆滤液侵入情况、射孔位置选择、估算地应力等。现有的反演偶极横波径向慢度剖面采用的频散分析方法(如加权频散相干法)的精度和分辨率不能确保反演结果的精度。引入一种高性能的频散分析方法——幅度与相位估计法,该方法对模拟和实际数据都有较好的处理效果,将其与高频约束反演法结合反演偶极横波慢度径向剖面,能够获得高精度的反演结果,并有效降低反演结果的非唯一性。处理结果验证了该方法的有效性。
Formation shear slowness is used to evaluation of borehole stability, drilling fluid invasion, perforation position selection and stress estimation. The existing dispersion analysis method may not have enough accuracy and resolution to ensure the precision of the inversion results. We introduce an algorithm of combining the dispersion analysis method of APES, which has good results for simulated and field data, with the constrained inversion method to rebuild the shear velocity radial profile. In this way, we can reduce the non-uniqueness and uncertainty while achieve higher accuracy. Processing examples with dipole sonic data are presented to demonstrate the validity of the algorithm.