Reservoir Characteristics And Geological Modeling Of The Upper He8 Reservoir In The Tao2 Area In Sulige Gas Field

Tao 2 area is located in the southeast of central Sulige Gas Field in Ordos basin,been put into develop in 2007,and has developed 323 wells now.The main development layer is the He8 member of shihezi formation in Permian.In allusion to the reservoir characteristics of Tao 2 area is low porosity,low permeability,thin reservoir thickness,horizontal change fast,poor longitudinal connectivity,and high heterogeneity,leading to it is difficult to predict the sand between wells and the effective reservoir.Therefore,the system and detailed study on characteristics of reservoir and prediction is need to provide reliable basis for further development in the study area.In this paper,taking sedimentary rocks,reservoir geology and logging geology as a guide,making full use of existing geological,logging,test gas and other materials to make further study of microfacies,distribution characteristics and reservoir characteristics of the upper of He8 member of the study area.During the study,reservoir properties model was established to reflect the underground gas reservoir property distribution,meanwhile,predicting the space distribution of reservoir parameters.The study shows that the upper He8 member in our study area has flat and undulating structure,presents the characteristics that“from north to south,east to the west”overall.Under the background of meandering river sedimentary,the sand presents in the plane as multiple channel sand body from the north north east to the south south west.Through the study of physical characteristics of upper of He8 member in Tao 2 area,we know the porosity of this area are mainly distributed in 6% ~ 15%,the permeability of the main points in 0.2~1.2m D.Through the comparison between deterministic modeling,sequential indicator modeling,truncated gaussian modeling and other sedimentary facies modeling methods,we choose the sedimentary facies of truncated gaussian modeling which can solve strong heterogeneity and intense phase change in the study area,and establish sedimentary facies model which can be more according with the practice of geological.Finally,sequential gauss random simulation method was used to set up reservoir physical property parameter model in the study area. From the perspective of the result of simulation,the reservoir physical property parameter model has fine corresponding relationship with sedimentary facies model,and provide good basis for the wells location optimization,and subsequent development of more efficient the area of Tao2 area.