Study on the environment effect and its correction method for the formation resistivity logging Data through casing
过套管地层电阻率曲线环境影响校正方法研究

Through casing resistivity logging is an electric logging technique measuring formation resistivity through metal casing. The measurement results are affected by borehole environment factors, such as casing, layer thickness/surrounding rock, cement sheath, so environment effect factors must be corrected in interpretation of through casing resistivity logging data. Based on discussing principle of through casing resistivity logging, aiming at ECOS, through casing resistivity logging tool of Russia that is introduced by Daqing oil field, this paper analyzes the response pattern of measurement results affected by layer thickness/surrounding rock and cement sheath respectively. Correction charts of layer thickness/surrounding rock effect and cement sheath are successful developed. Correction algorithm of layer thickness/surrounding rock and cement sheath are realized, and rationality of suggested method is verified by using model and logging example. This method can reduce the effect of cement sheath and improve resistivity measurement precision of thin layers that thickness is less than 1.0m, and provide guarantee for correct interpretation of through casing resistivity logging data.