Research On Production Influence Factors Of Fractured Wells In Tight Reservoirs

Tight oil reservoir have the characteristics of fine pore throat,narrow seepage channel,small grain,obvious microscale effect,develop abnormal pressure,high fracture productivity etc.The deformation of matrix as well as fracture have a great effect on seepage.Tight oil reservoir also have poor physical property,serious heterogeneity,small drainage radius and have no natural capacity,which causes it difficult to develop.In response of the above characteristic,the develop model of “Long horizontal well section+ volume fracturing” is mainly used all over the world.This method can access to economic benefits by forming a complex fracture network,which can increase the reservoir stimulation volume as well as increase initial production.Firstly,based on core and logging data,seismic data and other data of the real block,structure model,lithology model and sedimentary facies model are established in sequence through the combination of deterministic modeling and stochastic modeling.On this basis,large-scale and small-scale fracture modeling are respectively studied.The establish of largescale fracture is based on the seismic data through ant tracking way by deterministic modeling while small-scale fracture is based on imaging logging and conventional logging data.Firstly,the response patterns on conventional logs is established based on imaging logs and core observations.On this basis,the parameters used to describe the fracture is studied,including:aperture,fracture density,fracture permeability,fracture porosity,fracture azimuth and fracture dip.Then the discrete fracture network is generated.Finally,through the statistical upscaling method(Oda),fracture attributes which is used in dual porosity/permeability reservoir model are generated.The reservoir numerical simulation model is calibrated through history matching method.Then the impact of fracturing parameters on the productivity for fractured horizontal well is studied,including: horizontal length,fracture half-length seam,fracturing stages,fracture spacing.On this basis,the fracture parameters is optimized.