Offsets along the hydraulic fracture path have been observed in mapping of mined fractures and attempts have been made to reproduce their effects on fracture growth using numerical hydraulic fracture models.Such offsets have long been recognized as sites of restricted width in the fracture channel,potentially leading both to significant pressure drops and to proppant bridging as fluid and slurry move through the restrictions.New modeling results are presented that quantify these and other effects of offsets by using a coupled 2D hydraulic fracture model.Offsets are geometrically characterized by their angle with respect to the main fracture direction and by their length.Quantitative comparisons on fracture length,width and injection pressure are made for several offset angles and lengths.Large increases in net pressure and associated increases in overall fracture volume are shown,which can result in increased treatment costs,slower fracture growth,and shorter overall fracture length development compared with a straight fracture.
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