井孔周围轴对称声电耦合波:理论(I)  

Coupled Acoustic and Electromagnetic Waves Around A Borehole Embedded in A Porous Formation: Theory(I).

作　　者：胡恒山[1] 王克协[1] 

机构地区：[1]吉林大学物理系

出　　处：《测井技术》1999年第6期427-432,共6页Well Logging Technology

摘　　要：由于存在双电层，在孔隙地层中声波可引起渗透电流、流动电势及电磁场；电磁波也可以诱导渗流和声波。轴对称的声场（Ｐ—ＳＶ波）只产生轴对称的电磁场（ＴＭ 波），而轴对称的电场只产生轴对称的声场。在轴对称假设下，利用Ｐｒｉｄｅ声电耦合波控制方程和井壁上的边界条件，导出点声源激发的井内外声场和转换电磁场的计算公式、竖直电偶极子激发的井内外电磁场和转换声场的计算公式，并利用文内给出的公式对声电效应测井进行数值模拟。Due to the presence of an electric double layer in the matrix fluid surface, streaming current and electromagnetic field will form when acoustic wave propagates in a porous formation. Electromagnetic wave can also induce osmosis and acoustic field in the formation. Axisymmetric electromagnetic TM waves are only converted from axisymmetric acoustic P SV waves, and vise versa. The coupled acoustic and electromagnetic wavefields around a borehole embedded in a porous formation are formulated by exploiting Prides governing equations and the boundary conditions at the borehole wall. A point pressure source is adopted for modeling acoustic electric well logging, while a vertical electric dipole is adopted for modeling electro acoustic well logging. With the equations derived herin numerical simulation of acoustic electric well logging is made and its result is given.

关 键 词：井眼 声波 声电耦合波 轴向对称 电磁场 测井 

分 类 号：P631.811[天文地球—地质矿产勘探]