Depth reference point

{
  "id": "MLC-T-OAG-001020",
  "term": "Depth reference point",
  "field": "Oil and gas",
  "definition": "A precisely defined and consistently used datum from which all depth measurements in a wellbore are taken. This point is usually a fixed surface location, such as the rotary table, the top of the wellhead flange, or the derrick floor. All downhole depths, including those for casing shoes, perforations, and formation tops, are reported relative to this reference.",
  "subject": "Well Completions",
  "url": "https://mlchart.com/terminology/oil-and-gas/depth-reference-point/"
}