{{Short description|Liquids and gases contained in geologic formations}} '''Formation fluid''' refers to the naturally occurring liquids and gases contained in geologic formations.<ref name="ff">[http://www.glossary.oilfield.slb.com/en/Terms/f/formation_fluid.aspx Schlumberger Oilfield Glossary - Formation fluid]</ref> Fluids introduced during the drilling process are called drilling fluids.<ref>[http://www.glossary.oilfield.slb.com/en/Terms/d/drilling_fluid.aspx Schlumberger Oilfield Glossary - Drilling fluid]</ref> Fluids in an oil or gas reservoir are called reservoir fluids.<ref name="ff" /> The fluids flowing from the wellhead of an oil or gas well are called production fluids.
==References== <references/>
Category:Oilfield terminology
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