Reservoir Characterization Of Baikouquan Formation In The North Slope Of Mahu Sag

Recently,target of oil exploration have developed from convention reservoirsandstone,carbonate to unconventional reservoir-tight sand,glutenite.Glutenite is the main lithology of Baikouquan formation in North Slope of Mahu Sag,with retrogradation fan delta depositing from bottom to top,with tractive flow and debris flow existing.There are changeable lithology,poor properties of reservoir,and heterogeneous problems,which bring a lots difficult for reservoir characterization.And with low degree of exploration,there are long distance between wells and few number of wells which is uneven distribution.It is hard to describe and predicate the distribution of glutenite and fan delta merely depend on wells.Combining digit outcrop and wells information,this paper extract modeling parameters and build a three-dimension model of Baikouquan formation,to improving the accuracy of reservoir prediction.The following are the main contents of this paper:(1)Based on high-resolution sequence stratigraphy,equivalent formation framework is built.On this basis,three-dimensional model is established whose formation is dip to southeast with low degree and faults is dip to northwest.(2)Based on parameters extracting from digit outcrop and wells information,glutenite facies model is built separately by Sequential Indicate Simulation(SIS)and Multi-Point Facies Simulation(MPFS).Sequential Indicate Simulation apply variogram to describing spatial correlation of reservoir,but Multi-Point Facies Simulation use training image summarizing the conclusions of researchers which contain the provenance and geometry of reservoir.(3)With facies controlling,this paper research reservoir features and build reservoir physical properties models containing porosity permeability and oil saturation model,thus simulate the reserves and evaluate reservoir by physical properties.Under long inter-well distance,this paper combine outcrop and well research to extracting modeling parameters and generate three-dimensional models.The result shows training image can describe glutenite precisely,whereas can make up the shortage of variogram.In fan delta sedimentary system,glutenite is the most significant basement of reservoir,the major controlling factor of reservoir.This paper considers that the physical properties of the Baikouquan Formation are getting better from the bottom up,and the reservoir class I and II are increasing upwards,and the favorable reservoirs are concentrated in the northeastern and central regions of the research area.