Pressure Buildup Analysis of Fractured Wells Producing at High Flow Rates

The use of type-curve matching in pressure-transient analysis has become an essential method for estimating reservoir parameters with short-time data. Although the original type-curve matching techniques were based on solutions for pressure drawdown problems, these solutions have been extended, and justifiably so, to pressure buildup problems. However, there has been an indiscriminate use of these solutions interchangeably without proper justification for each application. As this paper points out, the drawdown solution is not the same as the buildup solution for a fractured well producing at high flow rates before shut-in. The bilinear period, however, is observed in the buildup solution. In this paper the effects of producing time on pressure buildup analysis also are investigated for fractured wells at low and high flow rates. An example is presented for analyzing short-time data for a fractured well producing at high flow rates.