Study On The Characteristics Of Turbidite Reservoir Space In The Sha-3 Formation In F154 Area Of Dongying Sag

Tight oil refers to the tight sandstone oil and tight carbonate rocks oil,which is trapped in the permeability of less than 0.2×10-3?m2.Turbidite reservoirs belongs to the tight sandstone reservoir.The turbidite reservoirs in the study area have deep burial depth,sand and shale thin interbeds,complex causes,and easy distribution.In this paper,the characteristics of turbidite reservoirs are described by core sampling observation,casting thin plate analysis,scanning electron microscopy and quantitative analysis of digital images.The basic characteristics of turbidite reservoirspace are summarized,There are several important factors in the development of the rock reservoir,and the following points are obtained.(1)The lithology of turbidite in the study area is mainly composed of lithic feldspar sandstone and feldspar lithic sandstone.Its low maturity,low cuttings and feldspar,quartz content is low;heterogeneous content is high,the cement is mainly calcite and kaolinite;the granularity is mainly fine sand,part is silt,Sorting medium,grinding round degree to the main angular,porous cementation,structural maturity is low.Through the study of the physical properties,the turbidite reservoirs in the third member of the Shahejie Formation in the F154 block belong to the low porosity and ultra low permeability reservoirs.(2)The types of reservoirs in the study area are studied by means of castings,scanning electron microscopy and so on.It is considered that the types of reservoirs in the study area are mainly divided into intergranular dissolution pores,,The primary hole,the casting hole,the hetero-hole and the intercrystalline pore.The main types of reservoir space are intergranular dissolution pore.The quantitative analysis of the reservoir space shows that the pore size distribution of the reservoir space is 5 ~ 10 um.The main pore size of the different reservoir spaces is different,the pore size of the intergranular pores and the intergranular pores is larger,and the pore size of the pores and interplanar pores is smaller,The pore size distribution of the primary pores is different.(3)Based on the study of the physical control factors of the turbidite in the study area,it is considered that the physical control factors of the turbidite reservoir in the study area include the detrital mineral composition,the interstitial material,the rock structure,the layer thickness and the diagenesis.The interstitial and layer thickness are the main factors controlling the physical properties of the study area.The reason for the low permeability of the study area is due to the clogging of the throat...