Study On The Effect Of Complex Fracture Network Fracturing On Productivity Of Deep Shale

With more and more proved reserves of unconventional oil and gas,as well as the increasingly mature exploration and development technology of unconventional oil and gas,unconventional oil and gas resources represented by shale gas have become the focus of domestic and foreign scholars’ research and the focus of attention of the world.Through the combination of reservoir numerical simulation and laboratory experiment,this paper explores the factors affecting the productivity of deep shale reservoir and the productivity change rules caused by them,so as to accurately predict the productivity of deep shale gas reservoir in the future and provide effective theoretical guidance for fracturing operation.Combined with the characteristic parameters of deep shale reservoir,the black oil model was established by Eclipse numerical simulation,and the fractured fractures were characterized by local encryption and equivalent conductivity.The effects of geological factors on productivity,including matrix permeability and matrix porosity,were studied.The influence factors of fracturing factors on productivity are also studied.Including fracture half-length,fracture number and fracture conductivity.Then,the range is calculated by orthogonal test with five factors and four levels.According to the range,the order of influence degree of deep shale productivity is arranged.The simulation results show that both geological factors and fracturing factors have a positive correlation on productivity,and the influence degree is in descending order of matrix permeability > matrix porosity > fracture half-length > fracture number > fracture conductivity.Subsequent fracture flow using the AFCS scheme-84 test system has carried on the deep shale rock plate flow conductivity of short term and long term experiment,the different types of proppant,concentration of different particle size,sanding,different combination modes,different pressure cycles experiment measurement,fitting for longterm diversion ability of diminishing and compared with constant under the guide of production for analysis.The results show that different aspects of proppant can have an impact on production.Long-term development of conductivity decline is more consistent with the actual production process of the reservoir,and production can be maintained through refracturing.