趋肤效应在过套管电阻率测井中的影响分析

Analysis of the Influences of Conductor Skin Effect upon Resistivity Logging through the Casing

过套管电阻率测井是通过测量金属套管上的微小电位差来计算地层视电阻率,本文分析了金属套管的趋肤效应现象,提出过套管测井激励信号源为超低频,过套管电阻率测井技术直接测量信号量级为微伏级,有用信号的量级为纳伏级。本文还分析了信号频率对检测的影响因素,并给出具体的解决方法。该结论用于指导过套管激励信号源以及弱信号检测系统的设计。

Cased hole formation resistivity(CHFR) logging calculates apparent formation resistivity by measuring slight potential difference on metal casing,The skin effect of metal casing is analyzed,a ultra-low frequency signal source is put forward in cased hole resitivity logging technology.In this technology,the direct detection signal order is microvolt,the useful signal order is nanovolt.The logging signal frequency effect on detection is analyzed,and the specific solution is given.The results has been applied in design of signal source and weak signal acquisition system.