Abstract
Taking Chang 6 reservoir in Q area of the southeast edge of Ordos basin as an example, the basic characteristics of the reservoir are studied from three aspects of reservoir physical properties, petrological characteristics and pore throat structure characteristics by means of X-ray diffraction, section analysis and identification, and the sensitivity and main control factors of the tight sand reservoir in the study area are studied and analyzed by water drive experiment. The results show that the lithology of Chang 6 tight sandstone reservoir in Q area of the southeast edge of Ordos basin is mainly feldspathic sandstone, and the grain size is mainly fine sand. The physical property of the reservoir is poor. The pore types of the reservoir are mainly intergranular pores and feldspar dissolved pores. The main throat types are flaky, curved and necked, and the throat connectivity is poor. Based on the physical properties, pore type and capillary pressure curve characteristics, the Chang 6 reservoir in Q area is divided into three types, of which, Type I reservoir is the reservoir with the best reservoir capacity and seepage capacity in this area. The reservoir in the study area is characterized by medium to weak velocity sensitivity, medium water sensitivity, weak to medium to weak salt sensitivity, medium to strong acid sensitivity and weak alkali sensitivity.
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