Reservoir Logging Evaluation On S4 Lacustrine Carbonate Formation Of Shao Jia Oilfield

Influence of lithology to well logging response of carbonate reservoir is bigger than influence of hydrocarbon.Carbonate reservoir is divided into lime reef, lime shore, lime mud, and limy dolomite exists locally.The distribution discipline of these subfacies is complicated in plane, variation of reservoir physical properties is great, and heterogeneity of reservoir causes difficulty for division of hydrocarbon bearing zones. Series of well logging is mostly adapted for old wells and is incomplete(mostly single acoustic wave slowness logging). All these factors cause difficulty and error for well logging data interpretation. So it is necessary for us to further complete and deepen evaluation pointing to this kind of reservoir.Based on acquisition of first hand data including experimental analysis of core, geological logging and well test, this paper determines dividing lower limit standards of lithology, physical properties and oiliness of reservoir.Utilizing different kinds of well logging data including drill coring, classification of geological sedimentary facies and analysis of limestone pore structure comprehensively, reservoirs and effective thickness are recognized effectively. Analyzing and researching 50 exploring wells in this area detailedly, including analysis of four characters, researching of characteristics of well logging responses of different sedimentary facies and physical properties, basic geological characteristics and response characteristics of well logging curves of lacustrine carbonate in this area are clarified and well logging curves sensitive to limestone are found which lays good foundation for researching well logging effective evaluating methods of this kind of reservoir.Based on determining techniques of lacustrine carbonate using well logging, mixed matrix calculating method for establishing reservoir parameters calculating model is proposed in this paper which utilizes P1/2 method to identify oil and water bearing zones effectively,Based on researching of characteristics of well logging responses comprehensively, a set of effective well logging evaluating method adaptive to this kind of reservoir is concluded further for recognition of reservoir fluid property, which establishes determining mode according to types of reservoir facies.Coincidence rate of evaluated results with well test reaches 70%.Second re-checking wok is launched for all exploring wells in this block. 10 meaningful wells are selected for second processing of well logging data.At last more accurate interpreting conclusions of reservoirs are provided which gives knowledge of reservoirs to exploration and developing of this kind of reservoir from now on.Actual application of methods in this paper in Shao-jia area of Shenli oil field proves the adaptability of methods.Researching thoughts and methods of lacustrine carbonate proposed in this paper provides interpretation process which increased coincidence rate of interpretation apparently.The researching results and methods proposed in this paper reaches desired target, which provided thoughts and methods for developing well logging data interpretation research of lacustrine carbonate reservoirs in other oil fields from now on.