本文论述了岩芯自然电动势的测量原理以及测量系统逻辑及其设计原则,该系统采用微机控制,测量精度高、重现性好、速度快。本文还分別给出了由热力学与电化学两种方法导出的岩芯自然电动势的理论表达式,其计算结果与实验系统的测量结果吻合很好。该项研究的进一步开发,可为泥质砂岩储集层的含油饱和度和剩余油饱和度的解释提供重要参数。 This paper discusses the measuring principle of core natural electromotive force, as well as the measuring system logic and its design principles. The system uses microcomputer control, which has high measuring accuracy, good reproducibility and fast speed. The theoretical expression of natural electromotive force of core derived from two methods of thermodynamics and electrochemistry is also given in this paper. The calculated results are in good agreement with the experimental ones. The further development of this study can provide important parameters for the interpretation of oil saturation and residual oil saturation in shaly sand reservoirs.