Study on Logging Evaluation Method of Porous Carbonate Reservoir in Akzhol Structural Belt Kazakhstan

Abstract

The size of throat in reservoir seriously affects the oil production. In the Pre-Caspian Basin, the porous carbonate reservoir in the Akzhol structural belt owns small throats and large pore sizes, and the porosities in some formation can reach about 10%. The results of oil test show that it is a dry layer. In this paper, aiming at the problems of low reservoir identification accuracy and the difficulty in evaluating the size of pore and throat in the study area, combined with core data such as the data of thin section and mercury injection, NMR, and physical properties, the logging responses that can characterize the size of pore and throat (when there are no fractures in the formation) could be obtained, which shows that the deep and shallow detection resistivity curve reduces drag and invades, the porosity of sonic time difference logging is different from that of neutron density, and the pore size range of nuclear magnetic logging reservoir. At the same time, the reasons of the above logging responses are analyzed. The comprehensive pore-throat index could be reconstructed base on the acoustic time difference, the difference of deep and shallow resistivity, and the curves of different fluid saturations of nuclear magnetic logging. The size of pore in the reservoir also could be characterized utilizing the production capacity per meter of the oil test layer. According to the research results, the accurate prediction of the productivity levels of multiple layers with high production can effectively instruct the logging interpretation of reservoirs in the Akzhol structural belt, and assist to attain the maximum regional exploration productivity. Simultaneously, reservoir characteristics can be re-recognized on the basis of this study, which provides significant instructions for the exploration and oil testing of the structural belts.

Copyright 2022, IFEDC Organizing Committee

This paper was prepared for presentation at the 2022 International Field Exploration and Development Conference in Xi’an, China, 16–18 November 2022.

This paper was selected for presentation by the IFEDC Committee following review of information contained in an abstract submitted by the author(s). Contents of the paper, as presented, have not been reviewed by the IFEDC Technical Team and are subject to correction by the author(s). The material does not necessarily reflect any position of the IFEDC Technical Committee its members. Papers presented at the Conference are subject to publication review by Professional Team of IFEDC Technical Committee. Electronic reproduction, distribution, or storage of any part of this paper for commercial purposes without the written consent of IFEDC Organizing Committee is prohibited. Permission to reproduce in print is restricted to an abstract of not more than 300 words; illustrations may not be copied. The abstract must contain conspicuous acknowledgment of IFEDC. Contact email: paper@ifedc.org.