Longdong Hedao-Baima Area Y10 Oilbeating Series Reservoir Characteristics Research

Ordos basin is the second largest sedimentary basin in China,it is a nearly ns-trending distribution type rectangular polycyclic superimposed basin,the edge of the basin structural belt development,in the interior of the basins structure activity is weak,Oil-gas resource is very rich,is the important energy base in our country.Hedao-baima are in the south of Shanbei slope of the Ordos Basin,stretch across Tianhuan Depressions,is an important oil-producing region.Lower Jurassic Yan'an Formation is one of the important oil-bearing series,is an important oil producing region of changqing oilfield,has the characteristics of small and fat.The Y10 reservoir group in widely distributed in the region.Sand body thickness vary greatly,serious heterogeneity and complex relations of oil and water.Based on comprehensive application of core observation,analysis of imaging well logging data and analysis data of assay,combining with thin section observation,etc,on the basis of a detailed stratigraphic division and correlation,conduct in-depth research for reservoir characteristics in the studied area system,and evaluate reservoir and predict favorable reservoir.Through the above analysis,this paper obtained the following results and understanding:1.According to the marker bed,sedimentary cycle,the principle,to fine stratigraphic classification and correlation of the study area,the Y10 reservoir group subdivided into 3 small layer:Y10,,Y102,Y103.2.Based on the predecessors' research results,according to the research of drilling data,logging response and lithology combination,sedimentary structure,and electrical characteristics,think that the study area in the early Jurassic yanan group Y10 reservoir belonged to braided stream depositional system tract,sedimentary microfacies have channel sand,central bar,alluvial flat microfacies and swamp microfacies,The reservoir sand bodies are extensively.3.Based on comprehensive application of conventional slice.casting slice.scanning electron microscope and cathode luminescence,thinks that the study area mainly development coarse grain.medium to coarse grain feldspathic litharenite quartz sandstone.Reservoir space with inter-partical and residual intergranular pore,the part of shown high angle tectonic fracture;The types of combination is mainly for the large pore with large throat,medium pore with medium throat and foramina pore with fine throat;Evenly distributed porosity,permeability variation range is big,serious heterogeneity;Experience in the acid diagenetic ambient,the diagenesis include consolidation,cementation,dissolution,rupturing and metasomatism,which belongs to stage A of middle diagenesis phase.4.Combines the result of the research of sedimentary facies and reservoir characteristics,the comprehensive evaluation of reservoir prediction in the study area,selected 6 ? type of reservoir area,provide geological basis for next step exploration and development.