简答题 翻译：Land maps are essential in establishing control wells and provide fundamental orientation. As Fig.2 illustrates, land maps which are readily available within most companies as well as readily available commercially, provide offset operators, total depth, formation tops and development dates. The land map is essential in establishing orientation and control.

问答题翻译：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.

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

问答题翻译：Also specified in gas purchase contracts is the maximum amount of sulfur the sales gas may contain.

问答题翻译In general, gas pipelines operate at higher pressure than crude lines; gas is moved through a gas pipeline by compressors rather than by pumps; and path of natural gas to the user is more direct.

问答题翻译：the pressure of a gas varies inversely as its volume, with temperature being constant.