isochronal test

isochronal test

[ī′sä·krən·əl ′test]
(petroleum engineering)
Short-time back-pressure test for low-permeability reservoirs that otherwise require excessively long times for pressure stabilization when wells are shut in.
References in periodicals archive ?
A 4-Point Isochronal test achieved stabilized flow rates of approximately 14 million cubic feet per day (~2,333 BOE per day) on a 48/64” choke, with associated condensate production increasing during testing.
The Manamo-1X well reached a maximum gas flow rate of 4.9 MMcf/d and 296 bbl/d 54AAPI condensate through a 16/64 choke in a three-stage isochronal test, and an average rate of 2.8 MMcf/d gas and 160 bbl/d condensate through a 12/64 choke at 3,720 psi well head pressure, on an extended flow test.
A 4-Point Isochronal test achieved stabilized flow rates of 6.98 million cubic feet per day (~1163 BOE per day) with a 25% drawdown.
A 4-Point Isochronal test on the Sidewinder-3 discovery well achieved a stabilized flow rate of 7.2 million cubic feet per day (1200 BOE per day) with less than a 50% drawdown.