翻譯：A portion of the sample is used to determine the gravity of the oil expressed in AIP unit the lighter the oil, the higher the API gravity .In most cases the price paid for the coude is determined in prat by the API gravity, hence ,the importance of careful gravity determination in each instance.

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：Nearly three-fifths of all known petroleum reserves on Earth is to be found in the territory of the various Arabic-speaking countries. Kuwait , for instance , which is a small nation at the head of the Persian Gulf , with an area only three-fourths that of Massachusetts and a population of about half a million , posseses about one-fifth of all the known petroleum reserves in the world.

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：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.