Study On The Characteristics Of Tight Reservoirs In Gaosheng Oil Layer In Leijia-Gaosheng Area

The densify oil exploration is a key promotion project of the joint-stock companies during the “12th Five-Year Plan” period.Liaohe Oilfield Company has selected the carbonate rock Formation in the Leijia-Gaosheng area as the target for The densify oilexploration.The densify oilexploration in Liaohe Oilfield has just started and is in the stage of research and understanding,and the technical preparation stage.so.This study has adopted test methods such as casting image analysis,capillary pressure curve,hole seepage,and nuclear magnetic data to study the performance of tight reservoirs in this area.And Starting from the basic experimental analysis and testing,we will carry out related researches such as lithology,reservoirs,and genetic environment to provide scientific basis for exploration and deployment decisions.This study research utilized more than thirty analytical and test techniques in the four aspects of rock mineral composition analysis,pore structure analysis,physical property analysis,and determination of mechanical properties,and finally achieved a wealth of research results.The first is to re-recognize the mineral composition,rock type,rock composition and distribution characteristics of the rock in this area.It is believed that the Formation in the Leijia-Gaosheng area is mainly a set of dolomite and analcite chemical precipitation,with accompanying Mixed argillaceous and sandy sedimentary rocks;lithology of high-grade reservoirs can be divided into five categories and twenty-four types of rocks,and the main reservoir lithology can be attributed to four types,namely mud-grained granitoids,muddy sand-containing crumbs.Mudstone,argillaceous mudstone,and carbonate rock shale;Second,for the first time,the main types of reservoir space for high-rise reservoirs in high-rise areas are intra-layer contraction joints,dissolved joints,secondary structural fractures,and inter-layer joints;the pores are mainly intergranular pores,dissolved pores,and intercrystalline micropores,and are eroded.The main minerals are gypsum,dolomite,etc.Thirdly,the physical properties of the lithology in the study area are put forward: the mudstone-grain granitoids are dominated by middle and high pores,medium-low osmoticite,and the mudstone-containing argillaceous mudstones have high porosity,low permeability,and especially low permeability.Muddy mudstone,mesoporous,low permeability,ultra-low permeability.The fourth is to test the mechanical potential of this set of rock through some test methods.It can be concluded that the potential of the set of rocks to produce cracks under the influence of stress is related to the mud content in the mineral in the area.Fifth,summarize the controlled factors of reservoir developmentand conduct a comprehensive evaluation of the reservoir.In the research process of the study,the favorable target horizons are determined in time to provide technical guidance for on-site drilling.