Oil and Gas Terms Beginning with “R” — Page 4

Any pit not part of the active (circulatory) system. The reserve pit may be used to store spare or waste mud, base oil or brine. In operations on land, the reserve pit is usually a plastic-lined, earthen pit, in which… Read more →

In onshore operations, an earthen-bermed storage area for discarded drilling fluid. These small reservoirs are used for several reasons. First, when properly arranged, most of the solids in the mud settle out and a… Read more →

Any pit not part of the active (circulatory) system. The reserve pit may be used to store spare or waste mud, base oil or brine. In operations on land, the reserve pit is usually a plastic-lined, earthen pit, in which… Read more →

A subsurface body of rock having sufficient porosity and permeability to store and transmit fluids. Sedimentary rocks are the most common reservoir rocks because they have more porosity than most igneous and metamorphic… Read more →

The act of building a reservoirmodel based on its characteristics with respect to fluid flow. Read more →

What Is a Reservoir Characterization Model? A reservoir characterization model is a three-dimensional static representation of a subsurface reservoir that integrates structural geometry, lithological facies, porosity ,… Read more →

The flow of fluids from one part of a reservoir to another or from one reservoir to another. The term is often used to describe crossflow from one reservoir compartment to another. Read more →

(noun) A comprehensive characterisation of a petroleum reservoir that integrates geological, geophysical, petrophysical, and engineering data to define the spatial distribution of rock properties, fluid properties, and… Read more →

A measurement of the vertical thickness of reservoirformation that is open to flow. The reservoir height is used in calculations and mathematical models to assess reservoir performance or potential productivity. Read more →

The variations in rock properties in a reservoir. The variations can result in directional variations in permeability. Geological processes, such as sedimentation, diagenesis and erosion, act to produce nonuniformities… Read more →

The act of producing a model of a reservoir. The model could include any of the geological, fluid or other characteristics of the reservoir. Read more →

What Is Reservoir Pressure in Oil and Gas? Reservoir pressure is the pressure of fluid (oil, gas, or water) within the pore spaces of a reservoir rock at a specified datum depth, typically measured or referenced to the… Read more →

What Is Reservoir Simulation? Reservoir simulation is the numerical modelling of fluid flow (oil, gas, and water) through a porous reservoir rock, used to predict reservoir behaviour under different production and… Read more →

Natural forces in the reservoir that displace hydrocarbons out of the reservoir into the wellbore and up to surface.Reservoir-drive mechanisms include gasdrive (gas cap or solution gasdrive), waterdrive (bottomwater… Read more →

(noun) The average duration that a fluid element or particle remains within a defined volume, such as a separator vessel, reactor, or section of a wellbore. In surface facilities, adequate residence time is essential… Read more →

The natural form that a section of coiled tubing string will take if spooled from the reel and allowed to rest without any tension applied. The residual bend results from the plastic deformation imparted as the string… Read more →

Oil that does not move when fluids are flowed through the rock in normal conditions, for example primary and secondary recovery, and invasion. Read more →

One of the four main components of petroleum, along with asphaltenes, aromatics and saturates (which include waxes). Resins, aromatics and saturates are also known as maltenes. Resin adds to the stickiness and viscosity… Read more →

A situation in which the resistivity of the flushed zone is greater than the resistivity of the undisturbed zone. Such a setting generally favors the use of induction devices, which respond to conductivity, rather than… Read more →

What Is a Resistivity Log? A resistivity log measures the electrical resistivity of formation rock and its contained fluids in ohm-metres (ohm-m) as a function of depth, using either induction or laterolog technology… Read more →

The ratio of the true resistivity to the resistivity of the same rock filled with water. The resistivity index can be expressed as I = Rt / Ro, where Ro is the water filled resistivity and Rt is the true resistivity. It… Read more →

A log of the resistivity of the formation made by an electrode device such as a laterolog. In this sense the term is used to distinguish the log from an induction measurement, which responds more directly to… Read more →

The ability to distinguish between separate points or objects, such as sedimentary sequences in a seismic section. High frequency and short wavelengths provide better vertical and lateral resolution. Seismic processing… Read more →

Relating to two or more logging measurements that have the same resolution. The term normally refers to vertical resolution, but could also be used for azimuthal or radial resolution. Read more →

Relating to two or more logging measurements that have the same response. The term normally refers to vertical resolution, but could also be used for azimuthal or radial resolution. The term implies that all the… Read more →

A core that has been cleaned but then flushed with reservoir fluids to reestablish the in situ condition of the rock. The main purpose of a restored state core is to measure the wettability and related properties such… Read more →

A chemical additive used to increase the thickening time of cementslurries or similar fluids that may have a limited pumping time. The increased pressure and temperature typically associated with deep wellbores requires… Read more →

The amount of time a liquid stays in a vessel. The retention time assures that equilibrium between the liquid and gas has been reached at separatorpressure. The retention time in a separator is determined by dividing… Read more →

A mud distillation unit used to measure the water, oil and solids content of a mud. It consists of a cylindrical body fitted with a mud sample holder, a heater element (or an oven) and an aluminum condenser. A graduated… Read more →

A technique for measuring the fluid saturations in a core sample by heating the sample and measuring the volumes of water and oil driven off. The sample is crushed and weighed before being placed in the retort. It is… Read more →