Research On Reservoir Characteristics Of Taiyuan Formation In ShenFu Area,Ordos Basin

Shen Fu Area is located in the Northeast part of the Ordos Basin,and it is the potential exploration areas,especially the Taiyuan formation of the Upper Paleozoic is the important gas productive reservoir in Shen Fu Area.Research subject is the Taiyuan Formation of the Upper Paleozoic in this paper,and the thesis is guided by sedimentology,reservoir geology,logging g eology and petroleum geology,combined with large number of casting lamella,cathodolumine scence,scan electron microscope and X-ray diffractions of clay minerals,the experimental data of physical property,porosimetry analysis and so on,systematically researched the lithological characteristics,physical characteristics,the evolution of diagenesis,pore structure types and characteristics of the Taiyuan formation in Shen Fu Area,and finished the research of four-pro perty relation.On this foundation,used Grey relational analysis calculating synthetic evaluatio n score.Through the study of sedimentary facies,characteristics,diagenesis and comprehensi ve reservoir evaluation of Taiyuan Formation in Shen Fu Area,we can draw the following conclusions:The area of Shen Fu of Taiyuan Formation as object in this research is braied delta plain.The rocks are from the northern source,and the marine-continental transitional facies was developed in the Upper Paleozoic strata of the area,which reflects the trend of uplifting of the northern strata and shallowing of the seawater.The lithological characteristics of reservoir indicate:The layer rock is mainly lithic sandstone,less feldspar lithic sandstone and lithic feldspars andstone.Detrital components include mainly quartz and lithic,but feldspar content is extremely low.The sandstones in the reservoir are dominated by clay minerals,mainly kaolinite,illite,siliceous and carbonate.The porosity type of the block was mainly rock debris dissolution pore,the second was the feldspar dissolvedpores.As a whole,the pore connectivity of the member 8 reservoir in Shen Fu Area is poor,and it is tiny pore throat based.Reservoir properties is relatively poor,porosity distribute in range of 4?10%,permeability distribute in range of 0.1?1×10^-3?m².Investigative area had entered into stage A of middle diagenesis phase,and some had entered into stage B of middle diagenesis phase.Based on the above-mentioned study,finished the research of four-property relation and net pay cut off thickness of reservoir.Then used Grey relational analysis calculating synthetic eval uation score.Finally determined the favorable zones was distributary channels in P₁t₂-2.