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 Prides 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.
出处
《测井技术》
CAS
CSCD
北大核心
1999年第6期427-432,共6页
Well Logging Technology
关键词
井眼
声波
声电耦合波
轴向对称
电磁场
测井
borehole acoustic wave coupled acoustic electromagnetic wave axisymmetry electromagnetic field
