The following are abbreviations and definitions of terms commonly used in the oil and gas industry. Unless otherwise indicated, natural gas volumes are stated at the legal pressure base of the state or area in which the reserves are located and at 60 degrees Fahrenheit and in most instances are rounded to the nearest major multiple. BOEs are determined using the ratio of six Mcf of natural gas to one Bbl of oil.
“Bbl” means a barrel of 42 U.S. gallons of oil.
“Bcf” means billion cubic feet of natural gas.
“Bcfe” means billion cubic feet equivalent, determined using the ratio of six Mcf of natural gas to one Bbl of crude oil, condensate or natural gas liquids.
“BOE” means barrels of oil equivalent.
“Completion” means the installation of permanent equipment for the production of oil or gas.
“Development Well” means a well drilled within the proved area of an oil or gas reservoir to the depth of a stratigraphic horizon known to be productive.
“Exploratory Well” means a well drilled to find and produce oil or gas in an unproved area, to find a new reservoir in a field previously found to be productive of oil or gas in another reservoir, or to extend a known reservoir.
“Gross,” when used with respect to acres or wells, refers to the total acres or wells in which a company, individual, trust, or foundation has a working interest.
“Horizontal drilling” means a drilling technique that permits the operator to contact and intersect a larger portion of the producing horizon than conventional vertical drilling techniques and can result in both increased production rates and greater ultimate recoveries of hydrocarbons.
“MBbls” means thousand barrels of oil.
“Mcf” means thousand cubic feet of natural gas.
“Mcfe” means 1,000 cubic feet equivalent, determined using the ratio of six Mcf of natural gas to one Bbl of crude oil, condensate or natural gas liquids.
“MMBbls” means million barrels of oil.
“MMBOE” means million barrels of oil equivalent.
“MMcf” means million cubic feet of natural gas.
“MMcfe” means million cubic feet of gas equivalent, determined using the ratio of 6 Mcf of natural gas to 1 Bbl of crude oil, condensate or natural gas liquids.
“Net,” when used with respect to acres or wells, refers to gross acres of wells multiplied, in each case, by the percentage working interest owned by a company, individual, trust, or foundation.
“Net production” means production that is owned by a company, individual, trust, or foundation, less royalties and production due others.
“Oil” means crude oil or condensate.
“Operator” means the individual, company, trust, or foundation responsible for the exploration, development, and production of an oil or gas well or lease.
“Present Value of Future Revenues” means the pretax present value of estimated future revenues to be generated from the production of proved reserves, net of estimated production and future development costs. Future net revenues are discounted to a present value of an annual discount rate whcih is typically 10%.
“Proved Developed Reserves” means reserves that can be expected to be recovered through existing wells with existing equipment and operating methods. Additional oil and gas expected to be obtained through the application of fluid injection or other improved recovery techniques for supplementing the natural forces and mechanisms of primary recovery can be included as “proved developed reserves” only after testing by a pilot project, or after the operation of an installed program has confirmed through production response that increased recovery will be achieved.
“Proved Reserves” means the estimated quantities of crude oil, natural gas, and natural gas liquids which geological and engineering data demonstrate with reasonable certainty to be recoverable in future years from known reservoirs under existing economic and operating conditions, i.e., prices and costs as of the date the estimate is made. Prices include consideration of changes in existing prices provided only by contractual arrangements, but not on escalations based upon future conditions.
Reservoirs are considered proved if economic producibility is supported by either actual production or conclusive formation test. The area of a reservoir considered proved includes: (a) that portion delineated by drilling and defined by gas-oil and/or oil-water contacts, if any; and (b) the immediately adjoining areas not yet drilled, but which can be reasonably judged as economically productive on the basis of available geological and engineering data. In the absence of information on fluid contacts, the lowest known structural occurrence of hydrocarbons controls the lower proved limit of the reservoir.
Reserves which can be produced economically through application of improved recovery techniques (such as fluid injection) are included in the “proved” classification when successful testing by a pilot project, or the operation of an installed program in the reservoir, provides support for the engineering analysis on which the project or program was based.
Estimates of proved reserves do not include the following: (a) oil that may become available from known reservoirs but is classified separately as “indicated additional reserves”; (b) crude oil, natural gas, and natural gas liquids, the recovery of which is subject to reasonable doubt because of uncertainty as to geology, reservoir characteristics, or economic factors; (c) crude oil, natural gas, and natural gas liquids that may occur in undrilled prospects; and, (d) crude oil, natural gas, and natural gas liquids that may be recovered from oil shales, coal, gilsonite, and other such sources.
“Proved Undeveloped Reserves” means reserves that are expected to be recovered from new wells on undrilled acreage, or from existing wells where a relatively major expenditure is required for recompletion. Reserves on undrilled acreage are usually limited to those drilling units offsetting productive units that are reasonably certain of production when drilled. Proved reserves for other undrilled units can be claimed only where it can be demonstrated with certainty that there is continuity of production from the existing productive formation. Under no circumstances are estimates for proved undeveloped reserves generally attributed to any acreage for which an application of fluid injection or other improved recovery technique is contemplated, unless such techniques have been proved effective by actual tests in the area and in the same reservoir.
“Recompletion” means the completion for production of an existing well bore in another formation from that in which the well has been previously completed.
“Reserves” means proved reserves.
“Royalty” means an interest in an oil and gas lease that gives the owner of the interest the right to receive a portion of the production from the leased acreage (or of the proceeds of the sale of production), but generally does not require the owner to pay any portion of the costs of drilling or operating the wells on the leased acreage. Royalties may be either landowner’s royalties, which are reserved by the owner of the leased acreage at the time the lease is granted, or overriding royalties, which are usually reserved by an owner of the leasehold in connection with a transfer to a subsequent owner.
“3-D Seismic” means seismic data that is acquired and processed to yield a three-dimensional picture of the subsurface.
“Tertiary Recovery” means enhanced recovery methods for the production of oil or gas. Enhanced recovery of crude oil requires a means for displacing oil from the reservoir rock, modifying the properties of the fluids in the reservoir and/or the reservoir rock to cause movement of oil in an efficient manner, and providing the energy and drive mechanism to force its flow to a production well. Chemicals or energy is injected as required for displacement and for the control of flow rate and flow pattern in the reservoir, and a fluid drive is provided to force the oil toward a production well.
“Working Interest” means an interest in an oil and gas lease that gives the owner of the interest the right to drill for and produce oil and gas on the leased acreage and requires the owner to pay a share of the costs of drilling and production operations. The share of production to which a working interest owner is entitled will always be smaller than the share of costs that the working interest owner is required to bear, with the balance of the production accruing to the owners of royalties. For example, the owner of a 100% working interest in a lease burdened by a landowner’s royalty of 12.5% would be required to pay 100% of the costs of a well but would be entitled to retain 87.5% of the production.
“Workover” means operations on a producing well to restore or increase production.