含煤地层转换波叠后横波波阻抗反演

叠后地震反演方法适用于纵波和横波地震资料的反演，但对转换波地震资料却不适用。为了实现利用转换波剖面得到横波波阻抗信息，通过建立转换波反射系数和横波反射系数之间的关系，直接从转换波地震数据中获取横波反射系数，把转换波叠后波阻抗反演问题转化为横波波阻抗反演问题。基于测井约束反演原理，利用横波反射系数和转换波解释层位建立初始横波波阻抗模型，优选反演处理参数，实现转换波叠后横波波阻抗反演。含煤地层转换波横波波阻抗反演结果，为进一步研究岩性参数比属性奠定了基础。和横波勘探相比，转换波勘探施工方便，工作成本相对低廉，因此利用转换波叠后地震反演获得横波波阻抗，是一种经济的办法。但由于在计算横波反射系数时采用了近似公式，所以反演结果精度会受到一定影响。

Post stack Shear Wave Impedance Inversion of Converted Wave in the Coal bearing Strata

Post-stack seismic inversion can be applied to inversion of P and S waves,but not to seismic converted wave.The shear reflection coefficient can be obtained from converted wave using the relationship between reflection coefficients of the converted wave and the shear wave,which is a question of how to change post-stack impedance inversion of converted wave into shear wave impedance inversion.Based on the inversion principle of well logging data,the initial shear wave impedance model was established using shear wave reflection coefficient and converted wave interpreted horizon.Optimizing inversion parameters helped the post-stack impedance inversion of the converted wave.The inversion results lay the foundations of further study on lithology and parameters' comparison.Compared with S wave exploration,converted wave exploration is easy to operate and is low in production cost.Therefore,S wave impedance inversion of converted wave will be an economical method,but the precision of inversion result would be affected due to the approximate formula taken in calculation of shear reflection coefficient.