Reservoir Fine Description Of Chang8Oil Set Of Yanchang Formation In The JJC Exploration Area Of Zhiluo Oil Field

JJC exploration area of Zhiluo oil field whose main oil-bearing formationslies are Chang8formation lies in the Fu county of south-east margin of Ordos basin, and it is belongs to secondary units Shanbei slope in construction.My paper is using multidisciplinary knowledge, especially the method of fine reservoir description to study formation, depositional microfacies, diagenesis, physical property, reservoir heterogeneity, reservoir sensitivity of Chang8formation. The author classified evaluation Chang8formation comprehensively combined with the feature of reservoir and accumulation analysis on main control factors, all of which provided for for further exploration work in the future of a reliable theoretical basis.According to the marker bed and the sedimentary cycle, the Chang8reservoir group is divided into two sub-groups,81and82, in which the82sub-group is the main producing reservoir. Research on the sedimentary facies illustrates that the reservoir of Chang8Formation which deposited in underwater distributary channel and distributary interchannel, its the most favorable facies belt is underwater distributary channel. The reservoir whose rock types consists of powder, fine-grained feldspathic sandstone and its sandstone has a low compositional maturity. Particles is well-sorted, more than the second round-subangular, and medium texture maturity. The diagenesiss in Chang8formation mainly includes compaction, cementation, metasomatism and dissolution and belongs to stage A in middle diagenesis. Reservoir characteristics research shows that the reservoir space in chang8reservoir is mainly composed of primary intergranular pores, the remaining intergranular pores, intragranular solution pores, intergranular solution pores, interquartz pores and so on. The core porosity of Chang8reservoir is1.3%-16.1%, and a mean porosity value of7.1%, the core permeability of Chang8reservoir is (0.012-2.440)×10-3μm2, and a mean permeability value of0.278×10-3μm2, Chang8reservoir overall performance for low porosity-extra low permeability reservoir. Sensitivity experiment measurement results show that the Chang8reservoir reservoir water sensitivity is weak, weak velocity sensitive, medium to weak acid, weak alkali sensitivity, strong salt sensitivity.The selection of representative reservoir physical parameters, the microscopic pore structure parameters, combined with the distribution of sedimentary facies, reservoir distribution, we study found that JJC exploration area Chang8formation major developed Ⅱ,Ⅲ,Ⅳ type reservoir, total predicted four favorable area of oil and gas exploration, including the focus of the study area Ⅱ and Ⅲ type reservoir mainly developed in good position of underwater distributary channel...