The Low Porosity And Low Permeability Reservoir Evaluation Of The ? Oil Group In Lower You Sha Shan Formation In Wunan Oil Field

With the exploration and development of most domestic oil fields entering the late stages,it is extremely urgent to search for new oil-bearing strata and increase efficiency.this thesis based on the low-permeability and low-permeability reservoirs of the Lower Youshashan Formation in Wunan Oilfield as the research object,and based on the theoretical knowledge of sedimentary petrology,well logging,petroleum geology,and structural geology.Using macro and micro,static and dynamic combination of ideas,to the research work area of the reservoir classification evaluation?oil group,and then find the favorable reservoir exploration and development,for ?oil group of Wunan Oilfield reservoir in fluid identification,the low porosity low permeability reservoir evaluation,and development to provide certain theoretical and technical guidance.Using well logging curve,lithology,sedimentary cycle characteristics of guidelines for the stratigraphic classification,determine the avoidances logo layer of ?oil group,and the ? oil group divided into 30 small layers.From single well facies-even well phase-phase plane train of thought to research of reservoir sedimentary facies,delta front main purpose layer was confirmed with the phase and coastal and shallow lake facies,the microfacies include far sand bar,sheet sand,sand dam,sand beach,shore and shallow lake of mud.Through the analysis of the Wells,the planar distribution of subfacies and microfacies is determined,and the sand dam and the remote sand dam microfacies are the most favorable facies.Comprehensive utilization of the electrical characteristics and testing,test data set up RILD-DEN,RILD-AC and RD/RILD-RILD intersection chart method,the well logging curve overlapping method,method of array induction logging,accurately identify the reservoir,oil and water,low resistance oil layer and water layer and dry tree layer,thereby increasing the reservoir oil-bearing layer.The study of diagenesis shows that the oil group is in the stage of early diagenesis,and the reservoir is mainly affected by mechanical compaction,cementation,metasomatism and corrosion.?low porosity low permeability reservoir of oil and strong heterogeneity of the reservoirs are mainly control factors,for the distribution of sedimentary microfacies and sand body development,compaction and cementation.Comprehensive the above research,using the qualitative factors and quantitative parameters matching the clustering analysis method,established the research area is low porosity low permeability reservoir classification evaluation standard,the ?group oil reservoir is divided into four categories,the main development ?reservoir,?classes and class reservoir prediction is the most favorable area,mainly distributed in the northwest of ?area near the W101 — WB12-10 well,in central north WB8-5 — WB6-5— newW4-4 — WB2-20 well and southeast newW3-4 — W7-7 — W9-12 — W18 well,combined with sand body plane distribution,forecasting ?-9 and ?-23 for optimal small layers.The evaluation criteria are developed into evaluation software,which can quickly and accurately identify and classify the reservoirs of new Wells and old Wells.