The manner in which #welltests are conducted and reported is always critical to the value of data obtained. Directive 40 (D40) defines the #AER quality standards required for well tests to fulfill survey requirements.
Stabilized initial reservoir pressures can be determined by six different subsurface methods. Traditionally, initial flow and build-up tests have been conducted, and via pressure transient analysis (#PTA), extrapolated reservoir pressures (p*) have been submitted. Notwithstanding, if pressures stabilize within ±2 kPa/h/6 h, the file can be submitted without analysis. Static gradient surveys can be utilized if: less than 14 day shut-in pressures change less than ±2 kPa/h/2 h, past 14 day shut-in can run any time. Mini-frac’ (#DFIT) tests, if run with subsurface gauges that remain on bottom at least 8 h, can be analyzed for compliance (p*). Finally, permanent downhole gauges and ESP pump intake pressure sensors can also be utilized in appropriate circumstances.