Research Of Tight Oil Reservoir In Lucaogou Formation Of Jimsar Sag Development Area And Geology Model Establishment

Because of its micro nano pores,reservoir compactness,lithologic diversity,multi attributes and strong heterogeneity,the reservoir fine description technology of tight oil reservoir is far more complex than the conventional reservoir.In-depth study of Permian Lucaogou Formation of Jimsar sag in Junggar basin about the structural characteristics,lithology characteristics,lithofacies characteristics,sedimentary environment characteristics,physical characteristics is fine reservoir description which can help understand oil and gas reservoir of Jimusaer sag and guid making further development scheme.Lucaogou Formation in Jimsar sag development area can be divided into two sections:the member 1 of Lucaogou Formation(P₂l₁)and the member 2 of Lucaogou Formation(P₂l₂),the main reservoir is“upper sweet point”in P2l2 Formation and“lower sweet point”in P2l1Formation.Lucaogou Formation layer in study area has low porosity and super low permeability characteristics,porosity<10%,permeability<0.1×10^-3?m².The Lucaogou group is in salty shore shallow lake sedimentary environment,the whole upper layers are in water inlet sedimentary system and lower layers are in water back sedimentary system,upper and lower group is bounded to the maximum flooding surface.The lithology of reservoir is mainly composed of fine sandstone and thin layer of carbonate rock which are usually distributed in the mutual layer,and more than transitional rock type of the two,the lithology is very complex.“Upper sweet point”mainly to salty lacustrine facies carbonate rocks deposited.The main type of micro facies is beach bar.In“lower sweet point”,the fine-grained clastic rocks are mainly deposited in the delta front and the former delta transition region,which is partly formed by the salty lacustrine facies,micro facies types are sheet sand,far sand bar,beach bar,beach bar and so on.The pore types in this area is various,there are dense pore,half filled crack,dissolution pore,intergranular pore,intragranular dissolution pore ect.Eventually,with method of seismic data to constrain tectonic modeling-determinacy sedimentary phase(lithofacies)modeling--different attributes modeling controlled by facies,establishing base material model in Lucaogou group“upper sweet point”reservoir.Then completed the multi parameter evaluation of the four types of reservoir modeling,from three-dimensional space to clear the quality of the reservoir location.