线圈法岩心复电阻率扫频测量系统研究

为了研究不同测量方法所测得的岩石电阻率或电导率的异同及关系 ,在实验室内研制了线圈法岩样复电阻率扫频测量系统 ,用该系统可以测量岩心复电阻率并与常规的电极法进行比较分析 ,给出两种不同测量方法所测值的异同 ,进而建立对应关系 ,解决归一化问题。同时也为今后复电阻率频谱测井方法和仪器的研究提供实验依据。主要介绍该测量系统的研制过程 ,包括测量信号的理论计算考察、样品设计、线圈系的优选、直耦消除、系统标定以及样品的测量等内容。研究结果表明 ,在室内用线圈法测量岩心复电阻率是可行的 ,而且被测信号幅度和相位均与岩石的电阻率有很好的对应关系 ,可用来探测岩石中地层水的饱和度。

Study of sweep-frequency measurement system for rock complex resistivity using coil antenna

A sweep-frequency measurement system for rock complex resistivity rock using coil antenna was established. The measurements of rock resistivity from the system were compared with the ones from conventional methods that use electrode. A relationship between them has been derived, which can be used for normalization and provide an experimental base for the future study of multi-frequency complex resistivity well logging. This paper introduces the theoretic computation of responses, design of sample, optimization of sonde, deletion of direct-coupled signal from emit coil, system calibration, and measurement of samples. The study showed that it is possible to get the complex resistivity of core sample in lab using coil antenna. Both amplitude and phase of the measured signal correlate well with the rock resistivity. They can be used to determine the water saturation of the rock.