A New Method of Reservoir Pore Structure Evaluation Based on Conventional Logging Data

Up to now, pore structure evaluation of complex reservoirs mainly depends on the core experiment analysis and new logging techniques, it is still difficult to evaluate the pore structure of complex reservoirs based on conventional logging data. Based on the experimental data of mercury capillary pressure curve, the relationship between mercury saturation and reservoir property parameters has been analyzed under different pressure. The result showed that there was a good relationship between them and the relationship showed obvious difference among different pore type reservoirs. Based on this knowledge and the method of flow zone index, the reservoirs were divided into four types. And the prediction model of pseudo-capillary pressure curve of different type reservoirs was established. The pore structure characteristics of complex reservoirs could be well evaluated according to the efficiency of mercury injection and the average capillary radius which were derived from the capillary pressure curve. All this has laid a solid foundation for the formulation and implementation of development plans for complex reservoirs.