过套管测地层电阻率的原理及应用

Principle of Formation Resistivity Logging Through Casing and Its Application.

以电磁场理论为基础 ,给出了套管井地层电阻率测井问题的理论公式 ,并分别对高、中、低及超低频 4种频率的磁力线模型进行了数值模拟。结果表明 :用超低频电磁波过套管测地层电阻率的测井方法是可行的。

The theoretical equations on formation resistivity log across casing are presented according to electromagnetic theory. Models for magnetic lines are simulated by numerical method in respect to four frequencies (high,medium, low and extra low frequency).It is shown that the new method using extra low frequency electromagnetic wave to measure the formation resistivity through casing is effective. It provides a theory foundation for the casedhole log interpretation and the development of logging tools.