Three-dimensional Reservoir Modeling And Reservoir Classification Evaluation Based On Dense Core Wells Pattern

The Xingshugang Oilfield has entered the late stage of development.The object of development has developed from the oil group to the small layer and even the single sand body.The main contradiction of extraction has also shifted from the contradiction among layers to the contradiction between layers,even the internal structure of sand body.In order to adapt to the next step of development and adjustment,it is necessary to carry out a new round of fine reservoir geology research under the condition of dense well pattern,and build up a three-dimensional visualization of reservoir maximum approximation of the actual underground prediction model that realize the accurate characterization of the plane and vertical heterogeneities of the reservoir and its internal properties.In this paper,a sedimentary facies-controlled geological modeling technique was used to model the PI group of Putaohua oil layer in the east of the Xingliu area of the oilfield.Firstly,the establishment of stratigraphic frameworks and the drawing of sedimentary microfacies maps were completed in combination with subdivided sedimentary units and subdivided sedimentary microfacies databases.On the basis of the layered structural model,a deterministic algorithm was used to establish the sedimentary facies model for each small layer,and the interlayer structure face of the meandering point dam in the PI32 was designed.With the microfacies boundary as the constraint and sequential Gaussian stochastic simulation as the method,the properties model(porosity and permeability)of all small layers of the PI group were established.The model of the properties(porosity and permeability)of each small layer is simulated.Through the above studies,a three-dimensional geological model was established to accurately characterize the heterogeneity characteristics of the PI group.Finally,according to the conventional mercury intrusion curve shape and parameters,taking into account the core and logging interpretation property data,the reservoirs are divided into four categories.From the three aspects of reservoir pore-throat size,sorting,and connectivity parameters,combined with the reservoir distribution,each type of reservoir was analyzed,and the reservoir seepage flow capacity decreased from one to four in turn.Through the comparison of the sedimentary microfacies model with the porosity and permeability models,the sedimentary facies-controlled property simulation results fully reflect the similarity of internal similarity of sedimentary facies and differences between sedimentary facies of the reservoir and its internal property parameters,and effectively characterize the variation characteristics of the reservoir plane heterogeneity.The vertical simulation results of the Porosity and Permeability Attribute Models are highly consistent with the corresponding coring geologic features,as well as the establishment of lateral interlayer in the meandering point dam further finely characterizes the vertical heterogeneity inside the thick oil reservoir.The reservoir evaluation clearly defines the reservoir type and the corresponding reservoir performance.