Definition(s)
Drill Stem Test
A test taken by means of special testing equipment run into the wellbore on the drill string (work string) to determine the producing characteristics of a formation.
Source: API RP 54, Recommended Practice for Occupational Safety for Oil and Gas Well Drilling and Servicing Operations, Third Edition, August 1999 (2007). Global Standards
Drill Stem Test (DST)
A test conducted to determine production flow rate and/or formation pressure prior to completing the well.
Source: API RP 59, Recommended Practice for Well Control Operations, Second Edition, May 2006. Global Standards
Drill Stem Test
A procedure to determine the productive capacity, pressure, permeability or extent (or a combination of these) of a hydrocarbon reservoir. While several different proprietary hardware sets are available to accomplish this, the common idea is to isolate the zone of interest with temporary packers. Next, one or more valves are opened to produce the reservoir fluids through the drillpipe and allow the well to flow for a time. Finally, the operator kills the well, closes the valves, removes the packers and trips the tools out of the hole. The test may be short (one hour or less) or long (several days or weeks) depending on the requirements and goals. Also there might be more than one flow and pressure buildup periods.
Source: IADC UBO / MPD Glossary, December 2011. Global Standards
Drill Stem Test
“Drill stem test” means a method of gathering data on the potential productivity of a formation by permitting the flow of formation fluids through the drill pipe.
[Mich. Admin. Code R 408 (2013)].
Source: Oil and Gas Drilling and Servicing Operations, Michigan Administrative Code R 408, February 8, 2013. Regulations