托福TPO4阅读文本及题目答案Part3.docx
《托福TPO4阅读文本及题目答案Part3.docx》由会员分享,可在线阅读,更多相关《托福TPO4阅读文本及题目答案Part3.docx(22页珍藏版)》请在淘文阁 - 分享文档赚钱的网站上搜索。
1、托福TPO4阅读文本及题目答案Part3 托福TPO是我们托福阅读的重要参考资料,为了便利大家备考,下面我给大家整理了托福TPO4阅读文本及题目答案Part3,希望大家喜爱。 托福TPO4阅读真题原文Part3 Petroleum Resources Petroleum, consisting of crude oil and natural gas, seems to originate from organic matter in marine sediment. Microscopic organisms settle to the seafloor and accumulate in
2、marine mud. The organic matter may partially decompose, using up the dissolved oxygen in the sediment. As soon as the oxygen is gone, decay stops and the remaining organic matter is preserved. Continued sedimentation-the process of deposits' settling on the sea bottom-buries the organic matter a
3、nd subjects it to higher temperatures and pressures, which convert the organic matter to oil and gas. As muddy sediments are pressed together, the gas and small droplets of oil may be squeezed out of the mud and may move into sandy layers nearby. Over long periods of time (millions of years), accumu
4、lations of gas and oil can collect in the sandy layers. Both oil and gas are less dense than water, so they generally tend to rise upward through water-saturated rock and sediment. Oil pools are valuable underground accumulations of oil, and oil fields are regions underlain by one or more oil pools.
5、 When an oil pool or field has been discovered, wells are drilled into the ground. Permanent towers, called derricks, used to be built to handle the long sections of drilling pipe. Now portable drilling machines are set up and are then dismantled and removed. When the well reaches a pool, oil usuall
6、y rises up the well because of its density difference with water beneath it or because of the pressure of expanding gas trapped above it. Although this rise of oil is almost always carefully controlled today, spouts of oil, or gushers, were common in the past. Gas pressure gradually dies out, and oi
7、l is pumped from the well. Water or steam may be pumped down adjacent wells to help push the oil out. At a refinery, the crude oil from underground is separated into natural gas, gasoline, kerosene, and various oils. Petrochemicals such as dyes, fertilizer, and plastic are also manufactured from the
8、 petroleum. As oil becomes increasingly difficult to find, the search for it is extended into more-hostile environments. The development of the oil field on the North Slope of Alaska and the construction of the Alaska pipeline are examples of the great expense and difficulty involved in new oil disc
9、overies. Offshore drilling platforms extend the search for oil to the ocean's continental shelves-those gently sloping submarine regions at the edges of the continents. More than one-quarter of the world's oil and almost one-fifth of the world's natural gas come from offshore, even thoug
10、h offshore drilling is six to seven times more expensive than drilling on land. A significant part of this oil and gas comes from under the North Sea between Great Britain and Norway. Of course, there is far more oil underground than can be recovered. It may be in a pool too small or too far from a
11、potential market to justify the expense of drilling. Some oil lies under regions where drilling is forbidden, such as national parks or other public lands. Even given the best extraction techniques, only about 30 to 40 percent of the oil in a given pool can be brought to the surface. The rest is far
12、 too difficult to extract and has to remain underground. Moreover, getting petroleum out of the ground and from under the sea and to the consumer can create environmental problems anywhere along the line. Pipelines carrying oil can be broken by faults or landslides, causing serious oil spills. Spill
13、age from huge oil-carrying cargo ships, called tankers, involved in collisions or accidental groundings (such as the one off Alaska in 1989) can create oil slicks at sea. Offshore platforms may also lose oil, creating oil slicks that drift ashore and foul the beaches, harming the environment. Someti
14、mes, the ground at an oil field may subside as oil is removed. The Wilmington field near Long Beach, California, has subsided nine meters in 50 years; protective barriers have had to be built to prevent seawater from flooding the area. Finally, the refining and burning of petroleum and its products
15、can cause air pollution. Advancing technology and strict laws, however, are helping control some of these adverse environmental effects. Paragraph 1: Petroleum, consisting of crude oil and natural gas, seems to originate from organic matter in marine sediment. Microscopic organisms settle to the sea
16、floor and accumulatein marine mud. The organic matter may partially decompose, using up the dissolved oxygen in the sediment. As soon as the oxygen is gone, decay stops and the remaining organic matter is preserved. 托福TPO4阅读真题题目Part3 1.The word "accumulate" in the passage is closest in mea
17、ning to grow up build up spread out break apart 2.According to paragraph 1, which of the following is true about petroleum formation? Microscopic organisms that live in mud produce crude oil and natural gas. Large amounts of oxygen are needed for petroleum formation to begin. Petroleum is produced w
18、hen organic material in sediments combines with decaying marine organisms. Petroleum formation appears to begin in marine sediments where organic matter is present. Paragraph 1: Petroleum, consisting of crude oil and natural gas, seems to originate from organic matter in marine sediment. Microscopic
19、 organisms settle to the seafloor and accumulate in marine mud. The organic matter may partially decompose, using up the dissolved oxygen in the sediment. As soon as the oxygen is gone, decay stops and the remaining organic matter is preserved. Paragraph 2: Continued sedimentation-the process of dep
20、osits' settling on the sea bottom-buries the organic matter and subjects it to higher temperatures and pressures, which convert the organic matter to oil and gas. As muddy sediments are pressed together, the gas and small droplets of oil may be squeezed out of the mud and may move into sandy lay
21、ers nearby. Over long periods of time (millions of years), accumulations of gas and oil can collect in the sandy layers. Both oil and gas are less dense than water, so they generally tend to rise upward through water-saturated rock and sediment. 3.In paragraphs 1 and 2, the author's primary purp
22、ose is to describe how petroleum is formed explain why petroleum formation is a slow process provide evidence that a marine environment is necessary for petroleum formation show that oil commonly occurs in association with gas 4.Which of the sentences below best expresses the essential information i
23、n the highlighted sentence in the passage? Incorrect choices change the meaning in important ways or leave out essential information. Higher temperatures and pressures promote sedimentation, which is responsible for petroleum formation. Deposits of sediments on top of organic matter increase the tem
- 配套讲稿:
如PPT文件的首页显示word图标,表示该PPT已包含配套word讲稿。双击word图标可打开word文档。
- 特殊限制:
部分文档作品中含有的国旗、国徽等图片,仅作为作品整体效果示例展示,禁止商用。设计者仅对作品中独创性部分享有著作权。
- 关 键 词:
- 托福 TPO4 阅读 文本 题目 答案 Part3
限制150内