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：A reservoir trap is a combination of physical conditions that will cause hydrocarbon liquids and/or gases and water to accumulate in porous and permeable rock and prevent them from escaping either laterally or vertically because of differences in specific gravity, pressure, fluid/gas characteristics, and/or lithology. It has the capability of collection, holding, and yielding hydrocarbon fluids and water.

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 application of physics to the study of rocks (geophysics)is very important in petroleum geology. In its broadest application geophysics makes a major contribution to understanding the earths crust and, especially through the application of modern plate tectonic(板塊構(gòu)造)theory, the genesis and petroleum potential of sedimentary basins. More specially, physical concepts are required to understand folds（褶皺）, faults（斷層）, and diapers（底辟）, and hence their roles in petroleum entrapment.

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：A paraffin base crude is an oil whose chief components are paraffins, and which completely distilled, leaves a solid residue of wax. An asphalt base crude is an oil composed primarily of cyclic compounds (mostly naphthenes) which, when distilled, leaves a solid residue of asphalt. Oils which fall in the middle of these categrories are classified as mixed base.

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：Gas lift is the method of artificial lift that uses an external source of high-pressure gas for supplementing formation gas to lift the well fluids. The primary consideration in the selection of availability and compression cost of gas.

翻譯：It has been suggested that an effective oil source rock generates 10-40 bbl or oil per acre ft (0.0013-0.0052 cc/cc) for each one per cent of organic carbon. This is approximately 500-2000 ppm by weight.

翻譯：The primary limitations for gas lift operations are the lack of formation gas of an outside source of gas, wide well spacing, and available space for compressors on off-shore plat forms. Generally, gas lift is not applicable to single-well installations and widely spaced wells that are not suited for a centrally located power system.