Experimental study on the shear‐slip characteristics of natural fractures in shale reservoirs

The injection of high-pressure fluid and the propagation hydraulic fractures (HF) can impact stress state natural (NF) in shale reservoirs, which will lead to shear slip NF that are a critical state. However, mechanics response mechanism during fracture approximation has not been well investigated, especially under triaxial conditions. This work focuses on shear-slip characteristics HF through experimental investigation. Each sample contains single rough tests, is injected pre-drilled hole at top sample. Meanwhile, deformation (axial radial deformation), axial stress, pressure experiment were recorded real-time. results show initiate tension or mode approaching process, produce both initiation modes. In addition, deviator confining pressure, approach angle, surface roughness all affect degree (NF). further reveal mechanical fracturing provide reference for optimizing process measures.