The Mechanics Of Fracture Initiation During Horizontal Well Fracturing On Clastic Reservoir

Hydraulic fracturing technology has been widely used in low-permeability oil reservoirs,but the understanding of control factors for multiple crack propagation laws of horizontal well fracturing near-wellbore is still insufficient.In the near wellbore,multiple fracture effects,perforation methods and construction parameters,and stratigraphic characteristics are not specific to the study of near-wellbore fracturing and complex fracture formation patterns.In order to make up for the deficiencies in the existing research,this paper first derives a feasible mathematical model by deriving the mathematic model of rock fracture pressure.Then,on the basis of the calculation model,the crack initiation and propagation of the cracks were studied using the ABAQUS.The effects of borehole azimuth,perforation parameters,and geological parameters on fracture initiation and multiple fractures were obtained.Based on the crack initiation model,an expansion model of the fracture was established.Through the fracture expansion model,the effects of borehole azimuth,perforation parameters,geological parameters,fracturing fluid parameters,and rock parameters on fracture deflection were obtained.Based on the model,the optimization of fracturing design was realized.A preliminary plan for fracturing design in Hangjinqi well area was proposed for reference.Through the above research,the fracture initiation mechanism of the near-wellbore fracture in the horizontal well of the Hangjinqi complex tight gas reservoir is helpful to the future hydraulic fracturing design,and the distortion of the crack propagation process can be better studied on the basis of this model.