Oil and Gas Terms Beginning with “G” — Page 6

Gumbo is the colloquial oilfield term for highly plastic, sticky, swelling clay-rich shale or claystone that hydrates and becomes extremely adhesive when it contacts water-based drilling fluid, causing it to stick to… Read more →

(noun) A perforating device, typically a shaped-charge carrier assembly, that is lowered into a cased wellbore on wireline, tubing, or coiled tubing and detonated to create penetrating holes through the casing, cement… Read more →

A gun barrel in oil production operations is a vertical cylindrical settling vessel used for gravity separation of crude oil from produced water and entrained gas, named for its characteristic tall, narrow shape that… Read more →

Gun clearance is the annular distance between the outer diameter of a perforating gun and the inner diameter of the casing string in which the gun is run — the gap that determines how the shaped charge's perforating jet… Read more →

Gun zero is the reference depth alignment procedure in perforating operations that establishes the exact correspondence between the position of the perforating gun in the wellbore and the depth scale of the open-hole or… Read more →

Debris, dirt, paraffin, oil, millscale and rust removed from a pipeline when a scraper or a pig is used for cleaning purposes. Read more →

A gunk plug (also called a cement-mud plug, cement slurry plug, or quick-set slurry) is a highly viscous mixture of Portland cement and native drilling fluid (typically bentonite-water mud or oil-based mud) that is… Read more →

A gunk squeeze is a remedial drilling operation in which a viscous slurry of bentonite mixed in diesel or another oil-based carrier fluid (commonly called a "gunk plug" or "diesel oil bentonite" or DOB pill) is spotted… Read more →

Gunning the pits is the deliberate, vigorous agitation of the drilling fluid in active mud pits by directing high-velocity jets of mud back into the pit through dedicated mud guns, which are nozzle assemblies fed by a… Read more →

Gyp mud (gypsum mud or gyp-treated mud) in drilling engineering is a calcium-based water-bearing drilling fluid system in which gypsum (calcium sulfate dihydrate, CaSO₄·2H₂O) is used as the primary source of calcium… Read more →

Gypsum is the hydrated calcium sulfate mineral with the chemical formula CaSO4 2H2O, the most abundant sulfate mineral in sedimentary basins and the first salt to precipitate when seawater begins to evaporate in a… Read more →