Formation mechanisms of hydraulic fracture network based on fracture interaction

The interaction between hydraulic fractures and natural fractures have significant influence on the geometry of hydraulic fracture network in fractured reservoirs. In previous mathematical model, the interaction relationship of non-intersecting fractures in propagation process were often been ignored, which resulted the inaccuracy of simulation results. Based on boundary element method and rock failure criterion, we established mathematical model to study the fracture interaction mechanisms and fracture network morphology under induced stress. Simulation results show that hydraulic fracture with incipient propagation superiority are more likely to have a rapid propagation and inhibit the continuous initiation of surrounding micro fractures. Under proper conditions, single natural fracture can deflect the propagation direction of hydraulic fracture by at least 22 & DEG;. Firstly proposed that shielding and transmission efforts of induced stress by natural fracture are the fundamental reason that affect the complexity of fracture network, which can reduce the normal stress around natural fracture by 50% in this paper. When the inclination Angle of natural fractures is between 45 and 70 & DEG;, it is more favorable to form complex fracture network. This study is of great significance for the control of fracture network morphology and the further improvement of fracturing effect.& nbsp;(c) 2021 Elsevier Ltd. All rights reserved.