Detailed experiments were performed in four instrumented boreholes to determine the growth pattern of an induced hydraulic fracture and its impact on flow through an ultra low permeability formation. The instrumentation allowed measurement of fracture pressure and width in three boreholes which were intersected by a fracture induced from a central well. The fracturing fluid was synthetic pore water to prevent formation damage. The experiments showed that because of the difference between the instantaneous fracture velocity and fluid velocity inside the fracture the fluid front lags behind fracture front. There was a large pressure drop along the length of the fracture which caused rapid narrowing of the fracture width, poor hydraulic communication along the fracture length, and localized growths and fluid movements.
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