دیکشنری تخصصی مهندسی نفت - نسخه آنلاین

n: the buoyancy above the waterline that keeps a floating vessel upright or seaworthy when the vessel is subjected to wind, waves, currents, and other forces of nature or when the vessel is subjected to accidental flooding.

n pl: the unproduced but recoverable oil or gas in a formation that has been proved by production.

a calculation of the amount of hydrocarbon reserves that are in the formation. Proven reserves have a very high degree of recovery with wells in place and techniques that are proven.

n: a subsurface, porous, permeable rock body in which oil and/or gas has accumulated. Most reservoir rocks are limestones, dolomites, sandstones, or a combination. The three basic types of hydrocarbon reservoirs are oil, gas, and condensate. An oil reservoir generally contains three fluids-gas, oil, and water-with oil the dominant product. In the typical oil reservoir, these fluids become vertically segregated because of their different densities. Gas, the lightest, occupies the upper part of the reservoir rocks;water, the lower part;and oil, the intermediate section. In addition to its occurrence as a cap or in solution, gas may accumulate independently of the oil;if so, the reservoir is called a gas reservoir. Associated with the gas, in most instances, are salt water and some oil. In a condensate reservoir, the hydrocarbons may exist as a gas, but, when brought to the surface, some of the heavier ones condense to a liquid.

n: a subsurface porous permeable formation in which oil or gas is present.

an independent hydrocarbon holding rock.

one of several reservoir drive methods including volumetric, depletion, gravity, gas cap, solution gas expansion, water drive, etc.

n pl: nonuniformities in the structure of properties of petroleum reservoirs, such as lenticular formation, pinch-outs, faults that cut across the reservoir, shale barriers, and variations in permeability.

n: the average pressure within the reservoir at any given time. Determination of this value is best made by bottomhole pressure measurements with adequate shut-in time. If a shut-in period long enough for the reservoir pressure to stabilize is impractical, then various techniques of analysis by pressure buildup or drawdown tests are available to determine static reservoir pressure.

the pore pressure in the reservoir, usually at current value unless otherwise specified.

n: computer model of a reservoir to predict reservoir behavior and to show production over time, allowing decisions about managing the reservoir to be made. The technique consists of digitizing data from appropriate geologic maps and engineering studies and entering them into a computer program, called the model. The model uses past and present values for each parameter of reservoir behavior.

n: see formation volume factor.