The Research Of Oil Distribution Regularity For Yan 9? Yan 10 Oil Reservoir In Zhuan Jing Block

This paper made in-depth research of oil distribution characteristics and controlling factors of Yan 9 oil reservoir and Yan 10 oil reservoir in ZhuanJing block of the Ordos Basin,guides by multidisciplinary geological theories and methods,combines with the study of regional geological situation,making full use of drilling,well logging,logging display and experimental analysis.Through fine stratigraphic division and contrast of the target stratum strata,summarizes the formation characteristics,and find out the characteristics of current tectonic.Using the method of“impression”to recover paleotopography form of the pre-Jurassic in the study area;Summarizes the sedimentary microfacie types and distribution characteristics;Sums up the characteristics of lithology and properties and analyze the reservoir heterogeneity characteristics.Define the oil distribution characteristics of yan9 oil reservoirs and yan10 oil reservoir and comprehensively analyze the controlling factors on the basic geological characteristics.The results show that the stratum thickness of the Yan 9 oil-layer in the study area is relatively stable,but the stratum thickness of the Yan 10 oil-layer changes greatly.The whole structure rises from west to east successively,and there are small low-amplitude nose structure and dome structure locally.The Yan 9 oil-layer belongs to the delta plain subfacies,developing the distributary channel microfacies,the natural levee microfacies and the marsh microfacies;the Yan 10 oil-layer belongs to the braided river sedimentary subfacies,developing the sedimentary microfacies of the channel sandbarsand the flood plain.The lithology of the reservoir is mainly medium and fine arkose,which has good properties and strong reservoir heterogeneity.It belongs to medium porosity and medium permeability reservoirs.The Yan 9oil reservoirs and Yan 10 oil reservoirs are mainly distributed in Yan 9?1,Yan 9?2 and Yan 10~1small layers.The oil of Yan9 oil reservoirs and Yan 10 oil reservoirs in the study area are mainly distributed in the areas with low-amplitude nose structure and dome structure.The low-amplitude structure provides favorable orientation for hydrocarbon accumulation and has favourable structure traps,which is the main controlling factor of oil and gas distribution.The sedimentary facies control the distribution of the reservoir and affect the distribution of oil and gas;the incised valley in the paleotopography provides a channel for hydrocarbon migration.