Paper: Afterflows And Buildup Interpretation

Field data on pumping well buildup curves illustrate long fluid column stabilization, U-tubing of liquid from tubing into the annulus, gas coning, high-pressure gas stringers, and high-pressure liquid stringers. Examples are given of truncation and of fitting two curves to the afterflow to get a better approximation of main pay and stringer properties, and of estimating unflooded stringer pressure from afterflow changes.