THE APPLICATION OF STOCHASTIC MODELING IN THE EARLY RESERVOIR DESCRIPTION OF LOW PERMEABILITY SANDSTONE RESERVOIRS

Chang 6 layer of Yanchang formation of ORDOS basin is typical fluvial reservoir with low porosity and super low permeability.During the early stage of oil reservoir description,it is difficult to study and evaluate the oil reservoir thoroughly because both of the static and dynamic information is scarce.The technology of reservoir stochastic modeling can describe the geological model's indeterminacy because of lack of information feasible.In the paper,the basic methods of stochastic modeling is introduced and skeleton model of Chang 6 zone of Yanchang formation of ORDOS basin is established.The sedimentary micro-facies model of the target formation and 3-D geological model of reservoir parameters,i.e.permeability and porosity,are also achieved using the algorithms of SIS(Sequential Indicator Simulation)and SGS(Sequential Gaussian Simulation),separately.The practical production results indicate that the prediction of advantage sand on the base of geological model of reservoir accords with the practical production highly.The technology of stochastic modeling is applicable and banausic in the early stage of oil reservoir description in completed fluvial facies reservoir in China.