A record that describes each formation encountered and lists the drilling time relative to depth, usually in 5 to 10-ft. (1.5 to 3-m) intervals.

A lease or a number of leases of adjoining tracts of land that constitute a unit of acreage sufficient to justify the expense of drilling a […]

An individual or group that owns a drilling rig or rigs and contracts services for drilling wells.

A driller, a derrickman, and two or more helpers who operate a drilling or workover rig for one tour each day.

Circulating fluid, one function of which is to lift cuttings out of the wellbore and to the surface. Other functions are to cool the bit and […]

The supervisor of drilling or workover operations on a rig. Also called a rig manager, rig supervisor, rig superintendent, or toolpusher.

The process of drilling into the oil or gas reservoir.

A wire rope used to support the drilling tools. Also called the rotary line.

Refers to drilling out of the residual cement which normally remains in the lower section of casing and the wellbore after the casing has been cemented.

The speed with which the bit drills the formation; usually called the rate of penetration.

See rig.

A connection component with ends either flanged or hubbed. It must have an internal diam at least equal to the bore of the blowout preventer and […]