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 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：Classification of reservoirs can be made on the basis of the texture, composition, and origin of the containing rock or the geometric configuration of the reservoir trap. Classification of reservoirs in the basis of rock texture and composition can assist in the prediction of reservoir performance. Variations in the mineralogy of reservoir rocks can be as important in reservoir performance as structural configuration or areal extent of the reservoir rock.

翻譯：This chapter deals with the fundamental properties of reservoir rocks. The properties discussed are (1) porosity - a measure of the void space in a rock; (2) Permeability - a measure of the fluid transmissivity of a rock; and (3) fluid saturation - a measure of the gross void space occupied by a fluid. These properties constitute a set of fundamental parameters by which the rock may be described quantitatively.

翻譯：For example ,the determination of the pump-setting depth and size of plunger that will lead to the maximum pumping rate in a particular well is a problem of considerable difficulty, which even today has not been fully or saris factorial solved; another interesting problem is that of gas anchors(bottom-hole separators); yet another is the interpretation of the results obtained form devices for determining the depth of the fluid level in the annulus during pumping.