基于基质矿物模量自适应提取横波速度反演方法

鉴于运用Xu-White模型时基质矿物模量(体积模量和剪切模量)取值较为困难,本文通过引入干岩石泊松比(σdry),借助Gassmann-Boit-Geertsma方程,提出-种改进基质矿物体积模量的自适应提取方法。在提取基质矿物体积模量的同时,也提取基质矿物剪切模量,从而有效地解决了取值问题,使得利用Xu-White模型准确反演横波速度成为可能。实际资料表明,基于基质矿物模量自适应提取的横波速度反演方法,不仅可以保证基质矿物模量的取值精度,而且能够提高反演横波速度的精度,反演与实测横波速度的相对误差不超过7%,误差均值仅为1.389%。

S-wave velocity inversion based on adaptive extraction of matrix mineral modulus

It is difficult to obtain matrix mineral modulus,such as bulk modulus and shear modulus,in Xu-White model.In this paper,we propose an improved method of adaptive extraction of matrix mineral bulk modulus by introducing into dry rock Poisson's ratio(σdry) with the Gassmann-Boit-Geertsma equation.When the matrix mineral bulk modulus is extracted,the shear modulus of matrix minerals is extracted too.Consequently,it solves the value issues effectively,and makes it possible to use the Xu-White model to accurate inversion of S-wave velocity.Field data inversion results show that the S-wave velocity inversion based on adaptive extraction of matrix mineral modulus is practicable.It can not only guarantee the accuracy of the matrix mineral modulus values,but also improve the accuracy of the inversion of S-wave velocity.The relative error between measure and inversion is less than 7%,and error mean is only 1.389%.