Abstract：Based on the formation mechanisms of stress interference of multi-fractures induced by network fracturing in shale gas reservoirs, this paper establishes a crossing criterion with consideration of remote stress, stress intensity near the tip of fracture and stress interference of multi-fractures. The results of model analysis illustrate that the ability of hydraulic fractures to cross natural fractures decreases under impact of stress interference of multi-fractures; Meanwhile, the net fracture pressure was higher when the fracture was longer, the distance between fractures was shorter, and the natural fracture was closer to the intermediate fracture, leading to larger interference stress between fractures. With decrease of the intersection angle between the hydraulic fractures and natural fractures, the ability of the former to cross the latter decreased within a certain range of stress ratio and friction coefficient, and increased when the stress ratio and friction coefficient were beyond this range. The crossing ability is not affected by the intersection angle under high stress ratios. These results may provide references for practical fracturing stimulation of shale gas reservoirs.
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