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Schlumberger Limited
Industry: Oil & gas
Number of terms: 8814
Number of blossaries: 0
Company Profile:
A calculation of the properties of the solid fraction of a rock from the combination of two logs. For example, by combining the density and neutron porosity measurements, it is possible to compute an apparent matrix density; by combining neutron porosity and sonic measurement, it is possible to compute an apparent matrix traveltime. The computations assume a particular fluid, usually fresh water, and particular response equations. The results are often displayed as quicklook logs for lithology identification. The word matrix is used here in the formation evaluation sense of the term rather than the geological one.
Industry:Oil & gas
A calcium soap of naphthenic acids in crude oil. Naphthenates are formed through interaction of naphthenic acids in crude oil with metal ions such as calcium and sodium. Insoluble in either the oil or water phase, and with a density between that of oil and water, naphthenates tend to accumulate at the oil/water interface and act as surfactants to help stabilize emulsions. Naphthenates can also be deposited as solids in pipelines, and can cause flow-assurance problems.
Industry:Oil & gas
A borehole that is not to gauge or is rugose. The term usually refers to the detrimental effect that such a borehole has on the response of logging measurements, in particular pad tools like the density or micro-resistivity. The existence of bad hole is usually determined by a caliper log and on various secondary measurements such as delta rho.
Industry:Oil & gas
A blend of organic and inorganic compounds such as scales, silts or clays. Migrating fines that become oil-wet often become targets for organic deposits, thereby creating a mixed deposit. <br><br>Mixed deposits are considered a type of damage. Treating this type of deposit requires a dual-solvent system composed of an aromatic hydrocarbon and an acid.
Industry:Oil & gas
A budgetary document, usually prepared by the operator, to list estimated expenses of drilling a well to a specified depth, casing point or geological objective, and then either completing or abandoning the well. Such expenses may include excavation and surface site preparation, the daily rental rate of a drilling rig, costs of fuel, drillpipe, bits, casing, cement and logging, and coring and testing of the well, among others. This estimate of expenses is provided to partners for approval prior to commencement of drilling or subsequent operations. Failure to approve an authority for expenditure (AFE) may result in delay or cancellation of the proposed drilling project or subsequent operation.
Industry:Oil & gas
A branch of mathematics that attempts to bring some understanding in the analysis of quantitative measurements. This science deals with the collection, analysis and interpretation of numerical data, often using probability theory. Statistics can also involve the generation of synthetic data between or within a group of measured data.
Industry:Oil & gas
A blank gas-lift valve placed in a gas-lift mandrel to isolate the tubing string from the annulus. Gas-lift valves frequently are replaced with dummy valves during intervention work on wells with gas-lift completions.
Industry:Oil & gas
A blank gun section or spacer installed between the top perforating-gun assembly and firing head in a TCP operation. The safety spacer serves to position the gun assembly a safe distance below the rig floor during arming and disarming operations. The spacer should be a minimum of 10 feet (3 m) in length. In some cases, a longer safety spacer will be required to ensure that the gun assembly is positioned safely below the living quarters or other occupied areas of the drilling rig.
Industry:Oil & gas
A basic threadform commonly found in oilfield applications. The thread profile of a round thread is designed to provide both mechanical strength and a hydraulic seal when made up to the correct torque.
Industry:Oil & gas
A bar, shaft or spindle around which other components are arranged or assembled. The term has been extended in oil and gas well terminology to include specialized tubular components that are key parts of an assembly or system, such as gas-lift mandrel or packer mandrel.
Industry:Oil & gas