Research Of Micro-fractures Stochastic Modeling Method Of SNESIM Algorithm Based On Multiple Point Statistics

Due to Iimitations of the traditional geostatistical methods on description of the spatial distribution,the multi-point geostatistical methods are becoming a major tool for reservoir modeling.It is widely applied in the modeling of fluvial facies and other macroscopical scale,but seldom applied in micro scale.If we accurately simulate microscopic fractures or pore throat distribution,It can be provided an important basis of the fine description of fractured reservoirs.The paper analyzes the principle and process of multiple point statistics.On this basis,the core of a well in Jiangsu oilfield is taken as the research object.SNESIM stochastic simulation method is used to establish micro fracture geological model.This paper studies the sensitivities of five important input parameters such as search radii and angles for search ellipsoid,number of multigrids,minimum replicates number and maximum conditional data,Subsequently,comparing the modeling results of SNESIM algorithm,Indicator Kinging Estimation,Sequential Gaussian Simulation,Sequential indicator Simulation from multiple aspects,we get a method of optimizing micro fracture geological models.The result shows that,the design of the search neighborhood and the choice of the grid series depend on the size of the training image and the structure information to be reproduced.In addition,under the smaller repeat number of data events,the.increase of the largest conditional data will make the reproduction effect of the structural information better.Combining variogram analysis results and the time of simulation and other aspects of information,the SNESIM stochastic simulation method has a greater advantage over the plane distribution and spatial structure.The results of this study can provide guidance for stochastic modeling of fractured reservoirs by using multi-point geostatistics.