The Study On Reserovir Characteristic On Yan 9 Oil-bearing In Dongkengdayangwan Area

The research area is Jingbian Dongkeng Dayangwan area of Yishaan slope in Ordos Basin and the horizon is Yan 9 of Yanan Formation in Jurassic.On the basis of data analysis of core description and slice identification,the research on the lithology,physical property,pore-permeability types,structural characteristics,diagenesis,reservoir sensitivity and heterogeneity of Yan 9 sandstone reservoir has been carried out to provide a reasonable theoretical basis for the next step of water-flooding development.The results show that the rock types of Yan 9 sandstone reservoir are mainly gray--grayish white coarse grained feldspar lithic sandstone,and secondly the lithic feldspathic sandstone.Among the particles,it is mainly for dot-linear contact The pore cementation and pore types are mainly intergranular pore and dissolved pore.Diagenesis types include compactionpressure solution,etc.The average porosity and average permeability of Yan 9 are respectively 14.2% and 3.38 × 10-3 m2 with good correlation between pore and permeability.It is weak water sensitivity,weak speed sensitivity,non-weak salt sensitivity and non-weak acid sensitivity by sensitivity experiment results in Yan 9 reservoir.While its sedimentary micro-facies are dominated by meandering river channel with positive rhythm of particle size in vertical,banded sand body--locally potato shaped,intra-layer medium heterogeneity,stronger interlayer heterogeneity and strong plane heterogeneity.