The Characteristics Analysis And Logging Interpretation Method Research Of Chang2 Low Resistivity In Dingbian Oilfield, Ordos Basin

A large number of exploration and development situation shows that low resistivity reservoir exists widely in complexity sandstone reservoirs,so that elusive nature of complexity and characteristics of the causes traditional to declined,leading to often overlooked or even missed. With the increasing demand for oil and gas resources in recent years,such accurate identification and evaluation of oil and gas reservoirs,whether in the New District or in the Old District are very important, draw attention from many exploration and development experts.The Ordos Basin reservoirs is the typical low porosity and low permeability reservoir type in China,Low resistivity reservoir were found in the Triassic Yanchang oilbearing strata,and widely distributed,causes more complex. Since conventional logging response characteristics of low resistance reservoir is more complex,brought many difficulties to identify and evaluate low resistivity reservoir.In this paper,take East Han and Jiyuan Chang-2 reservoir in Dingbian region as research objects,based on actual production of the oil field,combined theory and practical production,with well logging as the core method,and combined many other disciplines like sedimentology,petroleum geology and reservoir evaluation,made a systematic analysis on the mechanism and main causes of Chang-2 low resistivity reservoir,to carry identification method in the study area water reservoir complex relationship studies. Respectively,Statistical analyzing,summarizing and classifying the study area well logging,mudd logging,testing,core experiment analysis data and regional geological data,create a chart to summarize,classify and analyze the causes of low resistivity in Dingbian Chang-2 oil formation,including five major factors:high fixed water saturation,lithology fine grain size,high salinity formation water,clay content and composition of the oil reservoir water low differentiation. Analyzing the petrophysical properties of the typical wells in the study area,and of the lithology,electrical curves and reservoir,lithology and oil correlation analysis,determine the reservoir properties,and lithology of the largest oil-related conventional logging graph,define "four characteristicin study area Chang-2 reservoir.The logging response characteristics,combined with regional reservoir characteristics,geological structural characteristics,and saturation induction inversion method intrusive features a comprehensive explanation,established partitions hierarchical interpretation models,eventually formed a feasible method on the logging identification and interpretation of study area Chang-2 low resistivity reservoir.Proven to achieve high recognition accuracy on Chang-2 low resistivity reservoir.