Oil and Gas Terms Beginning with “S” — Page 14

(noun) The study of the origin, composition, distribution, and succession of rock strata to interpret depositional environments, correlate formations between wells, and identify stratigraphic traps that may contain… Read more →

A stratigraphic trap is a petroleum trap in which hydrocarbons are prevented from migrating further by a lateral change in the rock properties or stratigraphic relationships of the reservoir rock itself, rather than by… Read more →

Stratigraphy is the branch of geology concerned with the description, classification, and interpretation of stratified (layered) sedimentary rocks and their relationships in space and time, using the physical… Read more →

Layers of sedimentary rock that form beds. Read more →

A seismic streamer is a buoyant marine towed array consisting of a long, flexible assembly (typically 3 to 10 kilometers in length and 50 to 90 millimeters in outer diameter) of hydrophone groups connected by electrical… Read more →

In marineseismic acquisition, the lateral deviation of a streamer away from the towing direction because of a water current. Read more →

A decline of cement strength at elevated temperatures. This decline is pronounced at temperatures above 230°F [110°C], but it may be controlled by the addition of silica to the cement. Read more →

The force applied to a body that can result in deformation, or strain, usually described in terms of magnitude per unit of area, or intensity. Read more →

Stress corrosion cracking (SCC) is a failure mechanism in which a susceptible metal exposed simultaneously to tensile stress and a specific corrosive environment develops cracks that propagate at stress intensity levels… Read more →

Stress-corrosion cracking (hyphenated variant) is an alternate written form of stress corrosion cracking (SCC), referring to the same failure mechanism in which tensile stress, a susceptible material, and a specific… Read more →

Stress-induced anisotropy is the directional dependence of physical properties — primarily elastic wave velocities and mechanical strength — in a rock formation caused by the anisotropic in-situ stress field acting on… Read more →

The azimuth of the intersection of a plane, such as a dipping bed, with a horizontal surface. Read more →

A strike fault (also called a strike-slip fault in general structural geology usage, or specifically a fault whose strike is parallel to the regional structural trend or to the strike of the bedding) is a fault that… Read more →

A strike-slip fault is a geological fault on which the primary displacement of the two opposing rock blocks is horizontal — parallel to the fault's strike (the direction the fault plane intersects the horizontal… Read more →

A stripper rubber (also called a stripping element, rotating head rubber, or packing element) is the donut-shaped elastomeric sealing element mounted in a stripper head or rotating control device (RCD) that forms a… Read more →

Stripping in well intervention operations is the running or retrieving of a tubing string in a well that is under pressure, using a stripper or similar sealing device to contain the wellbore pressure and fluids while… Read more →

A stripping ram is a ram-type blowout preventer engineered to seal around a moving pipe string and hold primary pressure control during high-pressure snubbing and stripping operations, taking over the well-containment… Read more →

A stroke in oilfield drilling is one complete reciprocating cycle of a mud pump piston — the piston travels from one end of its cylinder to the other and back, displacing a fixed volume of drilling fluid with each… Read more →

Strokes per minute (SPM) is the rate at which the polished rod of a sucker rod pump unit completes full up-and-down cycles. Each stroke draws fluid into the pump barrel and pushes a fixed column of fluid up the tubing… Read more →

Structural analysis, in petroleum geology and geophysics, is the systematic characterization and interpretation of geological structures — including folds, faults, fractures, unconformities, salt diapirs, and igneous… Read more →

Structural shale is a type of clay mineral distribution in a sandstone reservoir where the clay exists as discrete grains or aggregates filling part of the pore space, in the same way that sand grains form the framework… Read more →

A variety of sealed geologicstructure capable of retaining hydrocarbons, such as a fault or a fold. Stratigraphic traps form where changes in rock type can retain hydrocarbons. Read more →

Structure, in geology, refers to a feature produced by deformation of the Earth's crust, such as a fold or a fault; to a feature within a rock such as a fracture or bedding surface; or, more broadly, to the spatial… Read more →

A structure map (also called a structural contour map) is a geological map that shows the three-dimensional configuration of a specific subsurface horizon — typically a formation top, reservoir surface, or fault plane —… Read more →

Stuck pipe refers to the condition in which the drillstring — including the drill bit, BHA, drill collars, and drill pipe — cannot be moved freely in the wellbore due to mechanical or differential pressure forces acting… Read more →

The portion of the drillstring that cannot be rotated or moved vertically. Read more →

A stylolite is a diagenetic structure found in carbonate rocks (limestones and dolomites) and some siliciclastic rocks (quartz-rich sandstones, chert) that consists of an irregular, interlocking seam of insoluble… Read more →

Styrene is the aromatic hydrocarbon compound with the chemical formula C6H5-CH=CH2 (also systematically named ethenylbenzene, vinylbenzene, or phenylethylene, and historically known as styrolene, cinnamene, or… Read more →

Slang for substructure, which is the part of the rig that supports the derrick, rig floor and associated equipment. Read more →

Subduction is the tectonic process in which a dense oceanic lithospheric plate descends beneath a less dense continental or oceanic plate at a convergent plate boundary, driven by negative buoyancy of the cold slab,… Read more →