Lesson 13-1 The search for oil
The deepest holes of all made for oil, and they go down to as much as 25,0000 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.
mineral /ˈmɪnərəl/ 矿物;矿物质;
deposit /dɪˈpɑːzɪt/ 沉积物，沉积层，存款
mineral deposit 矿藏;矿产;
boring /ˈbɔːrɪŋ/ 钻孔;钻屑
diameter /daɪˈæmɪtər/ 直径;对径
a foot in diameter 直径1英尺
my particular experience is largely in oil 我是专门搞石油的
drill /drɪl/ 钻探
mining /ˈmaɪnɪŋ/ 采矿;采矿业
derrick /ˈderɪk/ (油井的)井架，钻塔
block and tackle 滑轮组
haul /hɔːl/ 拖;(用力)拽;
rotate /ˈroʊteɪt/ (使)旋转，（使）转动;循环，
cutting bit 钻头
