Study On Resrevoir Characteristic Of The 10th Member Of Yanchang Formation In Shanbei Area,Ordos Basin

Because of the complex structure of the Ordos Basin,the reservoir is rich in oil and gas resources,which has a history of more than 30 years.The main exploration targets in the basin are stratigraphic lithologic gas reservoirs.The reservoir has the characteristics of "three low and one thin",that is,low porosity,low permeability,low abundance and thin reservoir.The key areas of this study are mainly in the central and western part of the northern slope of the Zhijing-Ansai area in the Ordos Basin.The area of about 1.2 x 104km2,north of Jingbian,South to Yongning,east to Ansai,west of Wuqi.Main research section for basin in Zhijing-Ansai area of Chang 10 reservoir group.In recent years,the exploration and development of oil and gas fields have been found,and the Chang 10 member of the Zhijing-Ansai area in Northern Shaanxi Province is an important oil and gas layer.Because of the lack of information about the reservoir characteristics and the existing research and development,the further exploration and development is limited.Therefore,in Zhijing-Ansai area outcrop profile and coring wellobservation and description as the basis,through the Casting sheet,SEM,NMR,X-RAY,Image granularity,Constant rate mercury injection and analysis method,and comprehensive theoretical basis of various disciplines.The study on the lithology of the Chang 10 reservoir in the study area includes reservoir rock types and reservoir petrology characteristics;Reservoir characteristics include reservoir pore type,reservoir physical properties,pore structure characteristics and formation mechanism of high porosity and permeability;The study of diagenesis includes the types of diagenesis and the division of diagenetic facies.The results show that the Chang 10 reservoir in Zhijing-Ansai area is mainly composed of lithic feldspathic sandstone and feldspathic sandstone.The main content of cement is mainly composed of zeolite and chlorite,and the content is relatively high.The study area is dominated by compaction,cementation and dissolution.Compaction and cementation destroy the primary pores.The dissolution can effectively improve the physical property of reservoir.The main pore types are intergranular pores,have a little feldspar pore and Zeolite pore.Reservoir physical properties are affected by various factors.Chang 10 reservoir in Zhijing-Ansai area belongs to low porosity and low permeability reservoir.which may lead to the actual production,but also because of the low porosity and low permeability reservoir.In this paper,the physical properties of the reservoir and the pore structure parameters are considered,according to Its Petrological Characteristics,the reservoirs of Chang 10 oil-bearing layers in the area of Zhijing-Ansai are divided into four groups,in Chang 10 oil-bearing layers the distribution of ? type is very broad,followed by ?type.This study provides a basis for the next step of the research area to develop high efficiency and reasonable development of Chang 10 reservoir.At the same time,it also has an important reference value for the exploration and development of Chang 10 reservoir in Zhijing-Ansai area of northern Ordos Basin.