EXPERIMENTAL STUDY ON THE AFFECTING FACTORS OF ELECTRICAL PARAMETERS FOR THE TOTAL DIAMETER CARBONATE RESERVOIRS

In order to improve the prediction accuracy of reservoir parameter logging, carbonate rocks with different degree of pore development in a block are selected. Then the self-developed SCAR- II full diameter measuring instrument was used to measure the resistivity of cores under different water saturation confining pressure conditions, On this basis, the electrical parameters a, b, m, n of the carbonate rocks in this area are obtained by using the classical Archie formula. The changes of resistivity, cementation index m and saturation index n with porosity and confining pressure were studied. The effect of porosity and confining pressure on resistivity is also discussed. The experimental results show that the resistivity of saturated water core increases with the increase of confining pressure, the resistivity of unsaturated water core decreases first and then increases with the increase of confining pressure. The dried rock resistivity increases greatly but decreases with the increase of confining pressure. Besides, However, the porosity index m increases with the increase of confining pressure. The saturation index n decreases with the increase of confining pressure, When the confining pressure is high, the variation range of m and n gradually decreases.