探寻石油
课文学习台
The Search for Oil
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第1段
The deepest holes of all are made for oil, and they go down to as much as 25,000 feet. But we do not need to send men down to get the oil out, as we must with other mineral deposits. The holes are only borings, less than a foot in diameter. My particular experience is largely in oil, and the search for oil has done more to improve deep drilling than any other mining activity. When it has been decided where we are going to drill, we put up at the surface an oil derrick. It has to be tall because it is like a giant block and tackle, and we have to lower into the ground and haul out of the ground great lengths of drill pipe which are rotated by an engine at the top and are fitted with a cutting bit at the bottom.
最深的洞，都是为勘探石油而钻的。这些洞最深可达地底 25,000英尺。但是，跟采矿要送人下去挖矿不同，开发石油无需将人送到地下。这些洞只不过是一些直径不足1英尺的钻孔。我个人的经历主要在石油行业。勘探石油对于改进深孔钻探的贡献比其它采矿业都要大。确定了钻孔地点，我们就在表面建起石油井架。井架必须建高，因为它像一个巨型滑轮组。我们必须把长长的钻杆钻进地下，钻杆底部装有钻头，并由顶部的钻机带动旋转，然后再将钻杆拉出地面。
第2段
The geologist needs to know what rocks the drill has reached, so every so often a sample is obtained with a coring bit. It cuts a clean cylinder of rock, from which can be seen the strata the drill has been cutting through. Once we get down to the oil, it usually flows to the surface because great pressure, either from gas or water, is pushing it. This pressure must be under control, and we control it by means of the mud which we circulate down the drill pipe. We endeavour to avoid the old, romantic idea of a gusher, which wastes oil and gas. We want it to stay down the hole until we can lead it off in a controlled manner.
地质学家需要知道钻头已深入到了什么岩层，因此时常要用取心钻头进行取样。这种钻头钻取一段平整的圆柱形岩石，从中能看出所钻透的地层情况。一旦到达油层，来自地下天然气或地下水的巨大压力，会让石油向地面流上来。必须让这种压力处于控制之中。 依靠泥浆在钻杆中向下循环，我们得以控制压力。我们尽量避免使用陈旧而不切实际的喷井方法，只会浪费石油和天然气。我们在能够以可控的方法将石油（从地底）引出来之前，先让石油留在井下。
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译文与解析据吴应时整理资料及本站首轮审校稿；词伙与练习提示为本站学习设计。原PDF第54—56页，2022年2月第2版。