The upper Triassic Xujiahe Formation in Sichuan Basin had the characteristics of wide distribution of sandbodies,big thickness of sediments,growth of multi-sources,big changes of the multi-source sediments and various periods of sediments.To represent the results of large scale of the sediments,a physical model was especially designed for the multi-sources in Xujiahe Formation.Because the features of different sources,different times and different positions were needed for simulation experiments,in the model design,3 sources were designed and six formations were simulated.Similitude principle combined with naturalness simulation principle was used for model design to present the real sedimentation characters.By using the similitude principle,the similitude correlation was established between the primary type and model for determining the boundary and designing the source features,settling the volume of flexible floor and the changes of the lake level.The hydrodynamic parameters were simulated for the experiment by naturalness simulation principle.The experimental parameters are repeatedly adjusted and validated by test-bed experiment and experiences,and the physical quantities required for experimental model are eventually determined.

Through the fine analysis of sedimentary facies,the microfacies proportion of different sand bodies is analyzed.The reservoirs in Beisanxi Area of Saertu Oilfield are divided into four reservoir structures:Type A and Type B,which are mainly distributary channel facies;Type C and Type D,which are mainly sheet sand of delta front.The geologic model is established using the geologic constrain modeling method.In a small layer for unit,the reserves of different microfacies are calculated and reserves distributions are analyzed,which shows that the reserves distribution of reservoir with different facies structure have different features and the reserves structures are different.On basis of traditional reserves estimation and considering the influence factors of facies structure on reserves control,this paper also considers that this method can directly represent the reserves of different genetic sand bodies and can provide a quantitative basis for analyzing the potentialities of different sand bodies.