Lost circulation

{
  "id": "MLC-T-OAG-002219",
  "term": "Lost circulation",
  "field": "Oil and gas",
  "definition": "The uncontrolled flow of drilling fluid from the wellbore into a subsurface formation, resulting in a reduction or complete loss of fluid return to the surface. This occurs when the hydrostatic pressure of the drilling fluid exceeds the fracture pressure of the formation or when drilling through highly permeable zones. Lost circulation can lead to well control problems, increased drilling costs, and environmental concerns.",
  "subject": "Drilling",
  "url": "https://mlchart.com/terminology/oil-and-gas/lost-circulation/"
}