Xiasiwan LLY Area,Single Sand Body Fine Characterization And Control Factors Analysis Of Tight Reservoirs In Chang 7 And Chang 8 Oil Formations

The single sand body portray have extremely unique research in sand body contact relationship and rock liquidity.In resent year it widely used in the expolration and caculate control in different grades inside the refine composite sand body's development,and become research key in how to rise up field exploitation.LLY area is locataed in Ordos basin major oli-producing sector Xiasiwan,recognized in oil base south-west,middle-south-west of whoe basin structure.This sector main producing part Triassic Yanchang group hanve large resource but field have hige diffreential,high water content and stongly density.Right now whole field is initialition to remaining oil develop stage in low-producing capacity.To ameliorate this situation,this paper use single sand body fine description technology,based in single sand characterization,expand to complex rock mass.During this process find fluid communication law in different contact relationship,then provide theoretical basis and guidance of tight reservoir development in research area.This paper use LLY area as target zone,Chang 7 and Chang 8 group as target sheaf,use local logging data and core information to be basal,use logging geology,sedimentary petrology asthe theoretical to fine divide this small layer,then delineate the single sand body in vertically direction by muddy layer and calcareous layer,and in horizontally.,defined by different sedimentation patterns,sedimentary geight differents,sediementary thickness,and superposition relationship between the river channels.Result is it can be divided into 3 categories by logging curve and thickness difference.The specific curve types are bell,box and half bell.Carry out studies effective monosandbody limit,qualitative identification and quantitative methods using multiple identification,and,reservoir heterogeneity and diagenesis of single sand body from the deposition control factors were analyzed.Finally,it is believed that the single sand body is affected by the combination of provenance,sedimentary facies,structure,heterogeneity and diagenetic factors.