Use of Extremely High Time-Resolution Production Data To Characterize Hydraulic Fracture Properties

Abstract

Abstract By employing flowback surface rate and pressure data recorded at very high frequency immediately following hydraulic fracture stimulation shutdown, it is possible to obtain estimates of fracture conductivity, fracture length and near-wellbore matrix permeability, as well as confirmation of closure pressure. Because the wellbore and induced hydraulic fracture are liquid filled at very early time, it is possible to observe meaningful signatures in the flowback production data when it is recorded with sufficiently high time resolution, on the order of 20 or more observations per minute. Dissipation of the super-charge is detectable, and the highly elliptical flow dominated by the fracture is clearly evident. Recognition of these flow regimes makes interpretation of fracture conductivity, effective length and an upper limit estimate of matrix permeability possible. Examples of actual field results are shown in the paper. When compared with published proppant bed conductivities for the expected stress loading, excellent correlation is obtained. The computed effective fracture lengths are somewhat shorter than that expected based on the design. In all cases, the near-fracture matrix permeabilities are higher than observed in later time production histories.