Oil and Gas Terms Beginning with “S” — Page 13

Steady-state behavior in a producing reservoir describes the condition where pressure and flow rate at every point in the formation become invariant with time, mathematically expressed as the partial derivative of… Read more →

What Is Steam in EOR? In enhanced oil recovery (EOR) contexts, steam is water vapor maintained in a two-phase liquid-vapor mixture or superheated vapor state and injected into heavy oil or bitumen reservoirs to deliver… Read more →

In steam-assisted gravity drainage (SAGD) operations, the steam chamber is the growing region of steam-saturated formation above and laterally around the horizontal producer-injector well pair where injected steam… Read more →

Steam management in petroleum engineering refers to the planning, monitoring, and operational control of steam injection in thermal enhanced oil recovery (EOR) projects, particularly steam-assisted gravity drainage… Read more →

Steam soak in heavy oil thermal recovery is a cyclic stimulation method in which high-pressure steam is injected into a producing well for a defined period (injection phase), the well is then shut in to allow the steam… Read more →

A steam trap is an automatic valve device installed in a steam distribution system that allows condensate (the water formed when steam gives up its latent heat to the process or equipment being heated) and… Read more →

Steam-assisted gravity drainage (SAGD, pronounced "sag-dee") is a thermal enhanced oil recovery method for producing heavy oil and oil sands bitumen in which two horizontal wells are drilled parallel to each other in… Read more →

The steam-oil ratio (SOR) is the operational parameter used to monitor the energy efficiency of oil production processes based on steam injection — providing the quantitative measure of how much steam (the energy input)… Read more →

What Is a Steamflood? A steamflood is an enhanced oil recovery (EOR) method in which steam is continuously injected through dedicated injection wells into a heavy oil or tar sand reservoir to heat the formation, reduce… Read more →

A steerable motor is a directional drilling bottomhole assembly (BHA) component that combines a positive displacement mud motor (a downhole device that converts hydraulic energy from drilling fluid circulation into… Read more →

A stem in slickline and wireline well intervention operations is a solid or hollow cylindrical steel weight bar run above the tool string to provide the downward force necessary to overcome the combined resistance of… Read more →

A step profile in resistivity log invasion modeling is a simplifying assumption about the radial distribution of formation fluids near the wellbore — specifying an abrupt change from the flushed zone (the immediate… Read more →

A step rate test (SRT) is a field procedure used in injection well testing, hydraulic fracturing operations, and well integrity evaluation in which fluid is injected into a well at a series of progressively increasing… Read more →

Stick-and-slip is a torsional vibration mode in rotary drilling in which the drill bit periodically arrests its rotation against the formation (sticks) due to torque exceeding the dynamic friction limit, then suddenly… Read more →

What Is Well Stimulation? Well stimulation is any treatment applied to a producing or injecting well to restore or enhance its productive capacity by improving the flow of reservoir fluids to the wellbore. Stimulation… Read more →

Stimulation byproducts are the chemical compounds generated during wellbore stimulation treatments — particularly acid stimulation and hydraulic fracturing — as a result of reactions between the injected stimulation… Read more →

A stimulation fluid in oil and gas well operations is any liquid or gaseous system pumped into a producing or potentially producing formation to enhance the well's productivity or injectivity beyond what the undisturbed… Read more →

An analysis related to a process involving a randomly determined sequence of observations, each of which is considered as a sample of one element from a probabilitydistribution. Read more →

(noun) Statistical and probabilistic techniques used in reservoir modelling and geostatistics to generate multiple equally probable realisations of reservoir properties (such as porosity, permeability, and facies… Read more →

The production of a model of a reservoir or field by using stochastic methods to interpolate between data measurements (usually wells). Read more →

A storage tank for oil production after the oil has been treated. Read more →

A measure of the volume of treated oil stored in stock tanks. A stock tank barrel is commonly abbreviated as STB. Read more →

A storm choke (also called a subsurface safety valve, SSSV, or storm valve in some historical usage) is a downhole valve installed in the production tubing string below the wellhead and the mudline (in offshore wells)… Read more →

A storm packer is a downhole safety device installed in the production tubing of a subsea well or in any well where the wellhead equipment must be temporarily removed or disconnected — typically a retrievable inflatable… Read more →

Strain in rock mechanics and structural geology is the permanent deformation evident in rocks and other solid materials that have experienced sufficiently high applied stress to cause irreversible change in shape or… Read more →

A device used to catch and hold the debris flowing in pipelines. Such foreign materials can cause severe damage to meters or other surface equipment. Read more →

To measure the dimensions of an oil tank, such as external diameter and height, using a steel tape. Once the measurements are recorded, they may be used to prepare tank tables, which describe tank capacity. Read more →

(noun) The process of calibrating the volume of a storage tank by measuring its internal dimensions at regular intervals and constructing a strapping table that relates the liquid level (gauge height) to the contained… Read more →

A graduated tape use to measure, or strap, producing tanks. The measurements are used to generate a tank table, which describes tank capacity. Read more →

Stratified flow is a multiphase flow pattern in which two or more immiscible fluids (liquid and gas, oil and water, or gas-oil-water in three-phase systems) flow simultaneously through a pipe in distinct, vertically… Read more →