1. n. [Well Testing]

The final flow sequence in a drillstem test. The initial shut-in period is usually followed immediately by an extended period of flow. The well is then shut in for the final buildup period. Data obtained during the final buildup period are analyzed to determine permeability thickness, kh, and skin effect, s. Final flow periods commonly range from 4 to 24 hours, and final buildup periods from 6 to 48 hours.

Antonyms: initial flow period

See: drillstem test,  final shut-in period,  flow period,  initial shut-in period,  permeability thickness,  skin effect