Lesson 13 The search for oil探尋石油
First listen and then answer the following question.聽錄音，然后回答以下問題。
What do oilmen want to achieve as soon as they strike oil?
The deepest holes of all made for oil, and they go down to as much as 25,0000 feet. But we not need to send men down to get the oil our, 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 is 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.
在所有洞穴中，為尋找石油所鉆出的洞是最深的，這些洞可深達25,000英尺。但是，我們不必像開采其他礦藏那樣，把人送到地下去把石油取出。這些洞只不 過是一些鉆孔，直徑不到1英尺。我是專門搞石油的，尋找石油比其他任何采礦業(yè)對改進鉆探作的貢獻都要大。當(dāng)確定鉆孔地點后，我們就在那里豎起一個井架。井 架必須很高，因為它像一個巨型滑輪組。我們必須把很長的鉆桿一節(jié)節(jié)地鉆入地下，然后再從地下拉出來。鉆桿頂部安裝的發(fā)動機帶動鉆桿旋轉(zhuǎn)，它的底部裝有鉆 頭。
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 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.
地質(zhì)學(xué)家需要知道鉆頭已以到達什么樣的巖層，因此時常要用芯鉆頭取樣。這種鉆頭能切割一段光滑的圓柱形巖石，從中能看出所鉆透的地層。一旦到達油層，石油 就會由于地下巨大的壓力流到地面上來，這種巨大的壓力來自地下天然氣或水。這種壓力必須加以控制，我們讓泥槳順著鉆桿向下循環(huán)，用這種方法來控制壓力。我 們盡量避免使用陳舊天真的噴井方法，那樣會浪費石油和天然氣。我們要讓石油留在井下，直到我們能用一種有控制的方法把它引上來為止。
New words and expressions 生詞和短語
mineral
adj. 礦物的
boring
n. 鉆孔
derrick
n. 井架
block and tackle
滑輪組
haul
v. 拖，拉
rotate
v. 使轉(zhuǎn)動
cutting bit
鉆頭
geologist
n. 地質(zhì)學(xué)家
coring
取芯鉆頭
cylinder
n. 圓柱體
strata
n. 巖層[復(fù)]([單]stratum或strata [誤用])
circulate
v. 注入，環(huán)流
gusher
n. 噴油井
Notes on the text課文注釋
1 they go down to as much as 25000 feet,
as much as 意為“多達”，“到達（量）”。
2 as we must with other mineral deposits
must 后面省去了與上句中相同的部分send men down。
3 a foot in diameter ， 直徑1英尺。
4 every so often, 時常。
5 by means of, 用.../靠...手段。
Lesson 13 課后練習(xí)和答案Exercises and Answer
