Oil and Gas Terms Beginning with “S” — Page 3

A small pit, typically located immediately after the shaker screens, which is used as a settling pit to separate coarser solids that accidentally bypass the shakers. Mud enters the pit at one side and exits via an… Read more →

The physical interface between the formation and the wellbore. The diameter of the wellbore at the sandface is one of the dimensions used in production models to assess potential productivity. Read more →

A condition encountered during some hydraulic fracturing operations whereby the fracture cannot accept further sand or proppant and only the carrier fluid is injected into the formation. A sandout occurs when the… Read more →

A clastic sedimentary rock whose grains are predominantly sand-sized. The term is commonly used to imply consolidated sand or a rock made of predominantly quartz sand, although sandstones often contain feldspar, rock… Read more →

The study of and description of sandstones, including the mineral content. In matrix stimulation, only the mineral surfaces contacted by the stimulation fluid will be dissolved, so a petrographic study often helps… Read more →

A transform from raw log data chosen so that a log recorded in these units will give the correct porosity of the formation providing the matrix is pure quartz and the pores are filled with fresh water. The unit, which… Read more →

Display ranges chosen for the density and neutron porosity logs such that the two curves will overlay at all porosity values providing the matrix is pure quartz and the pores are filled with fresh water. The most common… Read more →

A platform on which surface multiphase pumps can be mounted and connected to subsea multiphase pumps. Read more →

A solution that contains as much dissolved materials as it can hold at a given temperature. Precipitation of some components will likely occur if a more soluble compound is introduced or if the temperature is changed. Read more →

The relative amount of water, oil and gas in the pores of a rock, usually as a percentage of volume. Read more →

An equation for calculating the water saturation from resistivity and other logs. There are many saturation equations. Practical equations are all extensions of the Archie equation, which is valid for a rock with very… Read more →

What Is the Saturation Exponent? The saturation exponent (n) is a dimensionless parameter in Archie's water saturation equation (Sw^n = F × Rw / Rt = a × Rw / (φ^m × Rt)) that describes how resistivity increases as… Read more →

A unit equal to the percentage of a given fluid in the total volume of a pore space. The term is abbreviated to s.u. and lies between 0 and 100. Read more →

A short length of drill collar that has male threads on one end and female on the other. It is screwed onto the bottom of the kelly or topdrive and onto the rest of the drillstring. When the hole must be deepened, and… Read more →

What Is Scale in Oil and Gas Production? Scale in oil and gas production is the deposition of insoluble mineral salts from produced water or injected water onto wellbore tubulars, production equipment, perforations, and… Read more →

A chemical treatment used to control or prevent scale deposition in the production conduit or completion system. Scale-inhibitor chemicals may be continuously injected through a downhole injection point in the… Read more →

A type of inhibition treatment used to control or prevent scale deposition. In a scale-inhibitorsqueeze, the inhibitor is pumped into a water-producing zone. The inhibitor is attached to the formationmatrix by chemical… Read more →

What Is Scale Removal in Oil and Gas? Scale removal is a well intervention or facility maintenance operation that physically or chemically dissolves, disperses, or mechanically dislodges mineral scale deposits from… Read more →

A type of inhibition treatment used to control or prevent scale deposition. In a scale-inhibitorsqueeze, the inhibitor is pumped into a water-producing zone. The inhibitor is attached to the formationmatrix by chemical… Read more →

A perforating gun with a recess profile in the perforating gun body adjacent to the shaped charge. The scallop profile reduces the external burrs created as the perforating jet exits the gun body, thereby reducing the… Read more →

A graph in which data points are plotted but not connected. The x and y axes of the scattergram represent the two variables being plotted. Sometimes, the data points are coded by using color or symbols to represent a… Read more →

A treating chemical that is added to a drilling mud or other fluid to react with a contaminant to change the contaminant to a less harmful compound. If a contaminant is harmful at very low concentration, a scavenger… Read more →

A device for measuring the number and energy of gamma rays. The device consists of a crystal and a photomultiplier. In the crystal, an incident gamma ray imparts energy to electrons through Compton scattering,… Read more →

To inspect an area or to monitor activity. Read more →

A brief report about a well from the time it is permitted through drilling and completion. A scout ticket typically includes the location, total depth, logs run, production status and formation tops. Read more →

(noun) A mechanical device run inside casing or tubing on drillpipe, wireline, or coiled tubing to remove scale, cement, rust, paraffin, or other deposits from the inner wall of the tubular, restoring full bore diameter… Read more →

Equipment placed in a pipeline for inserting or retrieving a pipeline scraper (pig). Read more →

A device for cleaning mud and mud filtercake off of the wellbore wall when cementing casing in the hole to ensure good contact and bonding between the cement and the wellbore wall. The scratcher is a simple device,… Read more →

(noun) A downhole filtering device installed across a producing interval to prevent the entry of formation sand into the wellbore while permitting the flow of reservoir fluids. Screens are manufactured in various… Read more →

A preliminary assessment of the suitability of a reservoir for a particular process or development methodology. The assessment compares the reservoir characteristics to a number of screening criteria. The criteria are… Read more →