Oil and Gas Terms Beginning with “C” — Page 9

What Is a Coiled Tubing Unit? A coiled tubing unit (CTU) is the complete surface equipment package used for coiled tubing well intervention and workover operations — consisting of the CT reel (containing the coiled… Read more →

An insoluble organic deposit that has low hydrogen content. Coke, also known as pyrobitumen, is formed by thermal cracking and distillation during in-situ combustion. Read more →

A form of kriging that involves multiple variables. For example, well data may be used to generate one semivariogram, and three-dimensional seismic data used to generate another. Both semivariograms, along with a… Read more →

What Is Cold Heavy Oil Production with Sand (CHOPS)? Cold Heavy Oil Production with Sand (CHOPS) (also called sand influx production or wormhole-assisted heavy oil recovery) is a primary heavy oil recovery technique… Read more →

Nonthermal primary methods of heavy oilproduction, which include technologies such as production with horizontal wells, multilaterals, CHOPS, water or gas injection. Read more →

What Is Collapse Pressure? Collapse pressure is the external pressure differential acting on a casing or tubing string that, if exceeded, causes the pipe wall to plastically buckle inward — permanently deforming the… Read more →

A threaded coupling used to join two lengths of pipe such as production tubing, casing or liner. The type of thread and style of collar varies with the specifications and manufacturer of the tubing. Read more →

What Is a Collar Locator? Collar locator (also called a casing collar locator or CCL) is a simple wireline logging tool that detects the magnetic anomaly created by each casing collar — the threaded coupling joining… Read more →

A type of lock designed to be set in the recess of a tubing collar. Collar locks are compatible only with conventional thread connections where a space exists between the two tubing joints. Premium tubing grades have… Read more →

What Is a Collar Log? Collar log (also called a CCL log or casing collar log) is a wireline log run in cased wellbores that records the electromagnetic signature of each casing collar (coupling) as a distinctive spike… Read more →

The electrical device used on the axle of a spool or reel to provide electrical continuity between the rotating reel core and the stationary reel chassis. When using a coiled tubing string equipped with an electrical… Read more →

An interaction of lithospheric plates that can result in the formation of mountain belts and subduction zones. The collision of two plates of continental lithosphere, known as an A-type collision, can produce high… Read more →

A finely divided, solid material, which when dispersed in a liquid medium, scatters a light beam and does not settle by gravity; such particles are usually less than 2 microns in diameter. Some drilling fluid materials… Read more →

What Are Colloidal Solids? Colloidal solids (also called colloidal particles or the colloidal fraction) are the ultrafine clay and polymer particles in a water-based drilling fluid that are small enough — typically less… Read more →

What Is a Combi BOP? Combi BOP (also called a combination blowout preventer or CT BOP stack) is a compact, integrated well-control stack designed specifically for coiled tubing and wireline well intervention operations.… Read more →

What Does Come Out of the Hole Mean? Come out of the hole (abbreviated COOH ) is the drilling operation of pulling the drill string, completion string, or other tubulars upward from total depth (TD) to surface —… Read more →

What Is a Commercial Rate? Commercial rate is the minimum production flow rate from a well or reservoir that is economically sufficient to justify the full lifecycle cost of drilling, completing, and producing the… Read more →

What Is a Commingled Completion? Commingled completion is a well completion design that produces from two or more separate reservoir intervals simultaneously through the same wellbore and tubing string — without… Read more →

A term used to describe the flow pattern where two or more fluid phases may be present in a relatively even distribution. The flow rate and conduit geometry may cause an apparent mixing of the phases. However, if the… Read more →

In multichannel seismic acquisition where beds do not dip, the common reflection point at depth on a reflector, or the halfway point when a wave travels from a source to a reflector to a receiver. In the case of flat… Read more →

In multichannel seismic acquisition, the point on the surface halfway between the source and receiver that is shared by numerous source-receiver pairs. Such redundancy among source-receiver pairs enhances the quality of… Read more →

Method of seismic reflection surveying and processing that exploits the redundancy of multiple fold to enhance data quality by reducing noise. During acquisition, an energy source is supplied to a number of shotpoints… Read more →

In multichannel seismic acquisition, the common midpoint on a reflector, or the halfway point when a wave travels from a source to a reflector to a receiver that is shared by numerous locations if the reflector is… Read more →

Pertaining to traces that have the same offset, or distance between source and receiver. Read more →

Pertaining to traces that have a different source but share a receiver. Read more →

The combining of smaller federal tracts of land to total the acreage required by the US Bureau of Land Management and/or state regulations to form a legal spacing and proration unit. Read more →

The physical process by which sediments are consolidated, resulting in the reduction of pore space as grains are packed closer together. As layers of sediment accumulate, the ever increasing overburdenpressure during… Read more →

A change made to porosity measurements, such as those from sonic logs, to compensate for the lack of compaction, or the predicted loss of pore space as sediments are buried by overburden. Compaction corrections are… Read more →

The representative of the oil company or operator on a drilling location. For land operations, the company man is responsible for operational issues on the location, including the safety and efficiency of the project.… Read more →

The productive segment of an oil or gas field that is not in fluid communication with the remainder of the field. Productive compartments may become isolated at the time of accumulation by depositional processes or… Read more →