Initial flow period

{
  "id": "MLC-T-OAG-004362",
  "term": "Initial flow period",
  "field": "Oil and gas",
  "definition": "The first, brief flow of a drillstem test, lasting only minutes, in which the tester valve is opened to draw the pressure at the formation face below the mud hydrostatic pressure. It relieves pressure built up near the wellbore during drilling and shows that the tool and gauges are working. A longer initial shut-in follows, and the main flow period comes after that.",
  "subject": "Well Testing",
  "url": "https://mlchart.com/terminology/oil-and-gas/initial-flow-period/"
}