Study On The Microscopic Features Of Reservoir For Area One, East District No.7Reservoir, Karamay Field

In this paper, Area one,Eest District No.7reservoir in Karamay oilfield is studiedin this paper. Microscopic features of reservoir was studied by combined withgeological data, casting thin-section, electron microscope scanning,X-diffraction andParticle analysis,And the microscopic pore structure characteristics was fully studiedby means of the technologies of mercury injection and constant pressuremercury,based on those datas the reservoir was classified. These results show that:（1）The study area belongs to alluvial fan, where lithologic change isfast, thedistribution range of the grain-size is big, complex lithology features,bad gradationand psephicity of grains, elements and contents of cements and matrix variesgreatly.Rock types are fine sandstone, siltstone, coarse sandstone, sandyconglomerate,little sandy conglomerate and conglomerate. reservoir main rocktypes are fine conglomerate, little sandy conglomerate, thick coarse sandstone andsandy conglomerate.（2）Reservoir of study area belongs to a medium porosity,medium permeablereservoir,but there is a great difference in lithologic, Pore-throat types and ratio ofPore-throat, reservoirs polarization are great, and have strong anisotropism.（3）The reservoir space types of study area developed original intergranularpore, intergranular dissolved pore, intragranular dissolve pore, moldic pore, matrixpore, the main reservoir space types are original intergranular pore and intergranulardissolved pore,（4）The main clay types are kaolinite, montmorillonite and andreattite. kaolinitehave the highest content, on average,accounted for50percent, on highest,accountedfor74percent.so the water sensitive is low, which is favorable for Water drivedevelopment.（5）Analyzed for pore structure characteristic parameter by the technologies ofmercury injection and constant pressure mercury, by the technologies of constantpressure mercury, the average throat radius and permeability submitted a relationshipof good exponential function, The principal controlling factors in reservoir is throatradius,but when permeability is bigger than1000×10-3μm2, both of pore radius and throat radius have controlling action on the rock physical property（6）Based on the studys above, the evalution standard of reservoir of study areais established.