翻譯：THE OPEC oil cartel is about to turn 40, and the mood in the run-up to the grand heads-of-state party in Venezuela in less than three weeks time is jubilant. Not quite two years ago,oil was $10 a barrel and the cartel was on the brink of collapse. Now the oil price is well above $30 a barrel, and it shows little sign of coming down.

翻譯：The fluids of a petroleum reservoir are generally gas, oil, and water in varying proportions. Each phase can differ widely in composition and properties. Gas and oil, either as separate fluids or in mixtures, change their state or phase as reservoir pressure changes.

翻譯：An acidizing treatment for a sandstone formation normally will consist of sequentially injecting three fluids---a preflush, the hydrofluoric acid hydrochloric acid mixture, and an after flush. These fluids serve definite purposes.

翻譯：A porous medium has a permeability of one darcy when a single phase fluid of one centipoise viscosity that completely fills the voids of the medium, will flow through it under conditions of viscous flow at a rate of one cubic centimeter per second per square centimeter cross sectional area under a pressure or equivalent hydraulic gradient of one atmosphere per centimeter.

翻譯：There are two approaches to the problem of determining the fluid saturation within a reservoir rock. The direct approach is to measure, in the laboratory, the saturation of selected rock samples recovered from the parent formation. The indirect approach is to determine the fluid saturation by measuring some related physical property of the rock.

翻譯：the fluid must be identified by direct measurement of certain properties. These measurements involve securing samples of the fluids from the field. The simplest procedure is to make measurements of the properties of the produced fluids. The API gravity of stock-tank oil and the producing gas-oil ratio are routinely determined. The gas-oil ratio is ordinarily the ratio of volume, in standard cubic feet, of gas from the separator to the volume of stock tank oil both measured over the same time interval. If good field practice is followed, the gravity of the separator gas is determined. These data, together with estimates or observations of the reservoir pressure and temperature, can be used to estimate the properties of the reservoir fluids. Such estimates may be of limited accuracy.

翻譯：In the chapter and the next some aspects of rod pumping and of the instruments used to analyze pumping well behavior are discussed. Many different pumping systems are in current use , e.g. , conventional sucker rod pumping, long-stroke pumping , hydraulic ,centrifugal,and sonic pumping ,but no attempt is made to deal here with any other method than convention a sucker rod pumping.

翻譯：In addition to being useful as an exploration tool, subsurface maps are a necessary part of any reservoir engineering study; and petroleum engineers, as well as geologists, must be completely familiar with their construction and interpretation.

翻譯：After the casing string is run, the next task is cementing the casing in place. An oil well cementing service company is usually called in for this job although, as when casing is run,the rig crew is available to lend assistance.

翻譯：Gas lift is particularly applicable for lifting wells where high-pressure gas is available.Gas compressors may have been installed for gas injection, or high-pressure gas wells may be nearby. Since the cost of compression far exceeds the cost of down hole gas lift equipment, gas lift always should be considered when an adequate volume of high-pressure gas is available for wells requiring artificial lift. Most wells can be depleted by gas lift,which is particularly true since the implementation of reservoir pressure maintenance programs in most major oil fields.