托福閱讀(試題+答案+譯文):GeothermalEnergy

托福閱讀(試題+答案+譯文):GeothermalEnergy

【1】Earth's internal heat, fueled by radioactivity, provides the energy for plate tectonics and continental drift, mountain building, and earthquakes. It can also be harnessed to drive electric generators and heat homes. Geothermal energy becomes available in a practical form when underground heat is transferred by water that is heated as it passes through a subsurface region of hot rocks (a heat reservoir) that may be hundreds or thousands of feet deep. The water is usually naturally occurring groundwater that seeps down along fractures in the rock; less typically, the water is artificially introduced by being pumped down from the surface. The water is brought to the surface, as a liquid or steam, through holes drilled for the purpose.

【2】By far the most abundant form of geothermal energy occurs at the relatively low temperatures of 80° to 180° centigrade. Water circulated through heat reservoirs in this temperature range is able to extract enough heat to warm residential, commercial, and industrial spaces. More than 20,000 apartments in France are now heated by warm underground water drawn from a heat reservoir in a geologic structure near Paris called the Paris Basin. Iceland sits on a volcanic structure known as the Mid-Atlantic Ridge. Reykjavik, the capital of Iceland, is entirely heated by geothermal energy derived from volcanic heat.

【3】Geothermal reservoirs with temperatures above 180° centigrade are useful for generating electricity. They occur primarily in regions of recent volcanic activity as hot, dry rock; natural hot water; or natural steam. The latter two sources are limited to those few areas where surface water seeps down through underground faults or fractures to reach deep rocks heated by the recent activity of molten rock material. The world's largest supply of natural steam occurs at The Geysers, 120 kilometers north of San Francisco, California. In the 1990s enough electricity to meet about half the needs of San Francisco was being generated there. This facility was then in its third decade of production and was beginning to show signs of decline, perhaps because of over development. By the late 1990s some 70 geothermal electric-generating plants were in operation in California, Utah, Nevada, and Hawaii, generating enough power to supply about a million people. Eighteen countries now generate electricity using geothermal heat.

【4】Extracting heat from very hot, dry rocks presents a more difficult problem: the rocks must be fractured to permit the circulation of water, and the water must be provided artificially. The rocks are fractured by water pumped down at very high pressures. Experiments are under way to develop technologies for exploiting this resource.

【5】Like most other energy sources, geothermal energy presents some environmental problems. The surface of the ground can sink if hot groundwater is withdrawn without being replaced. In addition, water heated geothermally can contain salts and toxic materials dissolved from the hot rock. These waters present a disposal problem if they are not returned to the ground from which they were removed.

【6】The contribution of geothermal energy to the world's energy future is difficult to estimate. Geothermal energy is in a sense not renewable, because in most cases the heat would be drawn out of a reservoir much more rapidly than it would be replaced by the very slow geological processes by which heat flows through solid rock into a heat reservoir. However, in many places (for example, California, Hawaii, the Philippines, Japan, Mexico, the rift valleys of Africa)the resource is potentially so large that its future will depend on the economics of production. At present, we can make efficient use of only naturally occurring hot water or steam deposits. Although the potential is enormous, it is likely that in the near future geothermal energy can make important local contributions only where the resource is close to the user and the economics are favorable, as they are in California, New Zealand, and Iceland. Geothermal energy probably will not make large-scale contributions to the world energy budget until well into the twenty-first century, if ever.

托福閱讀試題

1.According to the processes described in paragraph 1, what is the relationship between radioactivity and the steam produced by geothermal heat?

A.Geothermally heated steam is produced when water is exposed to radioactivity deep underground.

B.When water is introduced into holes drilled thousands of feet in the ground, it becomes radioactive and turns to steam.

C.Radioactivity heats Earth's interior rock, which in turn can heat water to the point it becomes steam.

D.When a reservoir of steam in subsurface rock is produced by radioactivity, it is said to be geothermally heated.

2.The word "practical" in paragraph 1 is closest in meaning to

A.usable.

B.plentiful.

C.economical.

D.familiar.

3.The word "abundant" in paragraph 2 is closest in meaning to

A.economical.

B.familiar.

C.plentiful.

D.useful.

4.According to paragraph 2, which of the following is true about heat reservoirs with a temperature in the range of 80°to 180° centigrade?

A.They are under international control.

B.They are more common than reservoirs that have a higher temperature.

C.Few of them produce enough heat to warm large industrial spaces.

D.They are used to generate electricity.

5.According to paragraph 3, what is the connection between underground faults and naturally occurring steam?

A.Underground faults enable the heat from molten-rock material to escape upward to regions where it can heat surface water enough to produce steam.

B.Underground faults are created by steam that is produced in geothermal reservoirs deep inside Earth.

C.Underground faults create spaces in which natural steam is sometimes trapped.

D.Underground faults allow surface water to reach deep rocks that are hot enough to turn it into steam.

6.In paragraph 3, why does the author mention that in the 1990s The Geysers was in its third decade of production?

A.To provide the historical context of the geothermal production of electricity in the United States.

B.To imply that The Geysers was the first geothermal site to be put into production in California.

C.To help explain the signs of decline shown by The Geysers.

D.To explain why 70 new geothermal sites were put into electricity production in the late 1990s.

7.Which of the following can be inferred from paragraphs 2 and 3 about geothermal reservoirs?

A.Volcanic heat is associated only with geothermal reservoirs that have a temperature over 180° centigrade.

B.More countries produce power from geothermal reservoirs than use them for heating buildings.

C.Most geothermal reservoirs are suitable for producing electricity.

D.A higher geothermal reservoir temperature is needed to generate electricity than is needed to heat homes.

8.According to paragraph 4, extracting heat from very hot, dry rocks is difficult in part because

A.the underground rock must be fractured before heat can be removed from it.

B.the water above the rock is under very high pressure.

C.the rock breaks apart when water is pumped into it.

D.the water circulated through the rock must be much cooler than the rock itself.

9.The word "exploiting" in paragraph 4 is closest in meaning to

A.locating.

B.increasing.

C.making use of.

D.estimating the size of.

10.How is the problem that the surface may sink related to the problem that water heated geothermally may contain toxic materials?

A.Both problems could be solved by returning groundwater that is removed from an underground heat reservoir back to the reservoir after heat is extracted from it.

B.The problem of sinking is more difficult to solve than is the problem of toxic materials.

C.Land at the surface sinks because the rock beneath the surface is weakened when salts and toxic materials are removed from it in the process of extracting geothermal energy.

D.Both problems are caused by the fact that the hot groundwater in a heat reservoir dissolves the rock, which weakens the rock and makes the water toxic with salt.

11.Which of the sentences below best expresses the essential information in the highlighted sentence in paragraph 6? Incorrect choices change the meaning in important ways or leave out essential information.

A.Heat flows through solid rock very slowly, so it takes a very long time for geological processes to produce a reservoir of geothermal energy.

B.Geothermal energy is not renewable because heat flows very slowly through solid rock into or out of a heat reservoir.

C.The heat quickly removed from a heat reservoir is replaced so slowly by geological processes that geothermal energy is not practically speaking, renewable.

D.In most cases, heat travels into a heat reservoir so slowfy that it is a much quicker process to remove the heat from a reservoir than to replace it.

12.In paragraph 6, the author implies that in California, Hawaii, the Philippines, Japan, Mexico, and the rift valleys of Africa the potential size of the geothermal resource is so large that

A.it might be economically worth developing these sites even though geothermal energy is not renewable.

B.these sites will be the first geothermal energy sites to be developed with new technology.

C.these sites are likely to make a large-scale contribution to the world energy budget in the twenty-first century.

D.it does not matter whether they have naturally occurring deposits of hot water or steam.

13. Look at the four squares [■] that indicate where the following sentence could be added to the passage. Where would the sentence best fit? Click on a square to add the sentence to the passage. In either case, the heated water will usually be under considerable pressure, and so may have a temperature that is well above its sea-level boiling point of 100° centigrade.

Earth's internal heat, fueled by radioactivity, provides the energy for plate tectonics and continental drift, mountain building, and earthquakes. It can also be harnessed to drive electric generators and heat homes. Geothermal energy becomes available in a practical form when underground heat is transferred by water that is heated as it passes through a subsurface region of hot rocks (a heat reservoir) that may be hundreds or thousands of feet deep. ■【A】The water is usually naturally occurring groundwater that seeps down along fractures in the rock; less typically, the water is artificially introduced by being pumped down from the surface. ■【B】The water is brought to the surface, as a liquid or steam, through holes drilled for the purpose.■【C】

By far the most abundant form of geothermal energy occurs at the relatively low temperatures of 80° to 180° centigrade. ■【D】Water circulated through heat reservoirs in this temperature range is able to extract enough heat to warm residential, commercial, and industrial spaces. More than 20,000 apartments in France are now heated by warm underground water drawn from a heat reservoir in a geologic structure near Paris called the Paris Basin. Iceland sits on a volcanic structure known as the Mid-Atlantic Ridge. Reykjavik, the capital of Iceland, is entirely heated by geothermal energy derived from volcanic heat.

14. Directions: An introductory sentence for a brief summary of the passage is provided below. Complete the summary by selecting the THREE answer choices that express the most important ideas in the passage. Some sentences do not belong in the summary because they express ideas that are not presented in the passage or are minor ideas in the passage. This question is worth 2 points.

Heat reservoirs in the form of hot rock far beneath Earth's surface are a potential source of usable geothermal energy.

A.Heat reservoirs with a temperature from 80° to 180° centigrade can be used, as in France and Iceland, to heat buildings.

B.A number of countries now use geothermal reservoirs that contain water or steam above 180° centigrade to generate electricity.

C.Most heat reservoirs with a temperature above 180° centigrade cannot be used for energy because they are usually too close to recent volcanic activity.

D.The sinking of land above heat reservoirs and other environmental problems arise when water is pumped into a heat reservoir under high pressure.

E.Experiments are under way to determine if geothermally heated waters could be used as a source of certain minerals that have been dissolved out of hot rocks deep within Earth.

F.A number of issues, including how to extract heat from reservoirs that do not have a natural supply of water, will significantly limit the use of geothermal energy for the foreseeable future.

托福閱讀答案

1.細節(jié)題，問radioactivity和steam的關(guān)系，所以找雙關(guān)鍵詞，分別定位至本段第一句和最后一句，第一句說radioactivity提供了地球的內(nèi)熱，最后一句說水變成蒸汽到達地表，水受熱才能蒸汽，而這份熱量是geothermal energy提供的，這就是二者的關(guān)系，所以答案是C。A的水暴露在radioactive underground時候steam產(chǎn)生沒說;B水變成radioactive沒說;D的radioactivity產(chǎn)生蒸汽更不靠譜。

2.practical實際的，可用的，答案是A的usable，此題簡單，B plentiful大量的、C economical節(jié)省的和D familiar熟悉的，完全不對。

3.abundant大量的，充足的，所以答案是C的plentiful，我懷疑這個題的選項是不是跟上一道題弄混了，待定。不過C肯定是對的。此題也較簡單，其他答案完全不沾邊，不會的各位最好認真背單詞了。

4.以80到180度做關(guān)鍵詞定位至第一句，說最豐富的geothermal energy是在80到180度范圍內(nèi)的，所以同義替換是B的more common than higher temperature。A的international control原文沒說;C與本段第二句說反;D在本段沒提，但下一段說高于180度的可以用來發(fā)電，所以D說反了。

5.又是一個問兩者關(guān)系的題，找雙關(guān)鍵詞，定位至第三句，說natural hot water和natural steam僅存在于那些地點，地表水通過fault或者fracture滲到地下，碰到被加熱的blabla，答案明顯是D。A說fault使heat跑上來，和原文的方向說反了，原文是水跑下去;B說steam創(chuàng)造了fault完全不靠譜;C的steam被trap原文沒說。

6.修辭目的題，先讀例子所在句，只是細節(jié)，按照常規(guī)應該往前看，但前一句已經(jīng)在上題看過，與答案無關(guān)，所以往下看，而且看下一句另外一個原因是因為代詞this，下句說G經(jīng)歷了30年的運作，已經(jīng)顯示衰敗跡象，可能是因為過度開發(fā)，所以答案是C，A和B的內(nèi)容原文沒提;D本身也是個細節(jié)。

7.此題用排除法更快，A與第二段首句說反，錯;第二段只是說geothermal energy可以用來加熱building，沒說most，B錯;C和D都可以從兩段的首句看出來，第二段說最多的是在80到180度，第三段說發(fā)電需要180度以上，所以發(fā)電比別的溫度高，D對，C說反。

8.整個問題做關(guān)鍵詞定位至第一句，說從hot, dry rock抽熱量是特別難的，必須先fracture rock，水也要人工引入，所以答案是A。D沒說，B和C原文確實有說，但沒有回答為什么難，也就是那種答非所問選項，所以也不對。

9.exploit開發(fā)，利用，剝削壓榨，所以C的making use of正確。原文說人們正在實踐新的技術(shù)來怎么樣這種資源，B很顯然不對，資源如果想加就加那就好了;A定位和D估計數(shù)量都太初級了，而且現(xiàn)在的技術(shù)就可以定位和算儲量，明顯不應該是under way。

10.又是一個問兩者關(guān)系的題，本來應該找雙關(guān)鍵詞，但這段實在太短，找關(guān)鍵詞還不如讀完，快速掃完之后發(fā)現(xiàn)這兩件事情都是由于開采地下水引起的問題，而且最后一句說如果不把地下水補充回去就會有問題，所以答案是A。兩個問題之間是并列關(guān)系，既沒有比較也沒有因果，所以B和C都不對;D的dissolved溶解原文沒說，也不對。

11.原句的結(jié)構(gòu)是geothermal energy是不renewable的，因為blabla，所以前面的結(jié)果一定要有，A和D排除;原句的原因中有一個比較，說draw out比replace的快，C重現(xiàn)了這個比較，B沒有，所以正確答案是C。

12.修辭目的題，先讀細節(jié)所在句，說在這些資源如此充足的地方，資源的利用前景取決于economies of production生產(chǎn)經(jīng)濟，四個答案中只有A提到了開采是否劃算的問題，所以答案是A。B和D原文直接沒說;C跑到最后一句去了，跟例子也沒什么關(guān)系，注意倒數(shù)第二句MS也有例子，但是題目問的不是那個。

13.這道題有一個過渡點就夠了，in either case說明正確插入點之前必須有兩種情況，直接確定B，因為之前有usually和less typically兩種情況。

14.Heat選項對應原文第二段，正確;注意不要因為溫度和國家把這個選項當成細節(jié)，即使當成細節(jié)，也可以憑其他選項都不對的排除法解決。Most heat選項與原文第三段首句說反，不選。Experiments選項MS對應原文第四段最后一句，但原文說的是利用熱能，不是礦物，所以這個選項不選。A number of countries選項對應原文第三段首句，正確;注意不要因為溫度把這個選項當成細節(jié)。The sinking選項不知所云，好像有語法錯誤，不知道是不是我的TPO版本問題，但即使這個選項語法沒問題，說的也應該是第五段的細節(jié)，或者是干脆沒說，所以不選。A number of issues選項對應原文第六段，正確。

>> 雅思 托福 免費測試、量身規(guī)劃、讓英語學習不再困難<<