翻譯：A major oil company usually initiates the sequence of events that leads to the drilling of oil and gas wells in foreign fields, but independent oil operators pay for most of the wells in the United States. In fact, about 80% of all wells drilled in the U.S. today are financed by independents.

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：Practically every rig uses internal-combustion engines as its prime power source, or its prime mover.

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：A third means of assessing the maturity of rocks is by the pyrolysis of a small amount of the source rock. The temperature is raised rapidly and the material vaporized or formed by thermal breakdown of the kerogen is passed through a detector which records, on a temperature base, peaks representing these two bursts of volatile material. To a first approximation the peak at the lower temperature represents oil already generated; the peak at the higher temperature indicates oil capable of being generated at adequate maturity.

翻譯：In these early days, as lamp oil, was the important product and the main objects of refining was to extract as much of it as possible from the crude. Lubricants and some fuel oil were also sold, but gasoline was burnt off as unwanted and bitumen was also largely useless.

翻譯：The need for a greater understanding of the pumping process and for the ability to engineer pump installations to a close degree of tolerance is being accentuated by the trend to pump from greater and greater depths . Problems are relatively minor when the pump is at 10,000 ft.

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：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：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.