题目内容
Most earthquakes occur within the upper 15 miles of the earth’s surface. But earthquakes can and do occur at all depths to about 460 miles. Their number decreases as the depth increases. At about 460 miles one earthquake occurs only every few years. Near the surface earthquakes may run as high as 100 in a month, but the yearly average does not vary much. In comparison with the total number of earthquakes each year, the number of disastrous earthquakes is very small.[JP]?
The extent of the disaster in an earthquake depends on many factors. If you carefully build a toy house with an erect set, it will still stand no matter how much you shake the table. But if you build a toy house with a pack of cards, a slight shake of the table will make it fall. An earthquake in Agadir, Morocco, was not strong enough to be recorded on distant instruments, but it completely destroyed the city. Many stronger earthquakes have done comparatively little damage. If a building is well constructed and built on solid ground, it will resist an earthquake. Most deaths in earthquakes have been due to faulty building construction or poor building sites. A third and very serious factor is panic. When people rush out into narrow streets, more deaths will result.?
The United Nations has played an important part in reducing the damage done by earthquakes. It has sent a team of experts to all countries known to be affected by earthquakes. Working with local geologists and engineers, the experts have studied the nature of the ground and the type of most practical building code for the local area. If followed, these suggestions will make disastrous earthquakes almost a thing of the past.
There is one type of earthquake disaster that little can be done about. This is the disaster caused by seismic sea waves, or tsunamis. (These are often called tidal waves, but the name is incorrect. They have nothing to do with tides.)
In certain areas, earthquakes take place beneath the sea. These submarine earthquakes sometimes give rise to seismic sea waves. The waves are not noticeable out at sea because of their long wave length. But when they roll into harbors, they pile up into walls of water 6 to 60 feet high. The Japanese call them “tsunamis”, meaning “harbor waves”, because they reach a sizable height only in harbors.
Tsunamis travel fairly slowly, at speeds up to 500 miles an hour. An adequate warning system is in use to warn all shores likely to be reached by the waves.
But this only enables people to leave the threatened shores for higher ground. There is no way to stop the oncoming wave.
65. Which of the following CANNOT be concluded from the passage??
A. The number of earthquakes is closely related to depth.?
B. Roughly the same number of earthquakes occur each year.?、
C. Earthquakes are impossible at depths over 460 miles.?
D. Earthquakes are most likely to occur near the surfaces.?
66. The destruction of Agadir is an example of_____.
A. faulty building construction? B. an earthquake’s strength?
C. widespread panic in earthquakes? D. ineffective instruments?
67. The United Nations’ experts are supposed to_____.?
A. construct strong buildings? B. put forward proposals?
C. detect disastrous earthquakes? D. monitor earthquakes?
68. The significance of the slow speed of tsunamis is that people may_____.?
A. notice them out at sea? B. find ways to stop them?
C. be warned early enough? D. develop warning systems?
65---68 CABC
The Iceberg Was Only Part ofIt
What doomed the Titanic is well known, at least in outline. On a moonless night of April 15, 1912, the ship hit an iceberg in the North Atlantic ,with 1,500 lives lost.
A century later many people presented new theories to explain the real reason for the disaster. Now two new studies argue that rare states of nature played major roles in the disaster.
The first says Earth’s nearness to the Moon and the Sun — a proximity not matched in more than 1,000 years — resulted in record tides that help explain why the Titanic met with so much ice, including the fatal iceberg.
Recently, a team of researchers found an apparent explanation in the heavens. They discovered that Earth had come unusually close to the Sun and Moon that winter, enhancing their gravitational pulls on the ocean and producing record tides. The rare orbits took place between December 1911 and February 1912 — about two months before the disaster came about. The researchers suggest that the high tides refloated masses of icebergs traditionally stuck along the coastlines of Labrador and Newfoundland and sent them adrift into the North Atlantic shipping lanes.
And a second, put forward by a Titanic historian from Britain, contends that the icy waters created ideal conditions for an unusual type of mirage(海市蜃楼) that hid icebergs from lookouts whose duty was to watch carefully for danger ahead and confused a nearby ship as to the liner’s identity, delaying rescue efforts for hours.
Most people know mirages as natural phenomena caused when hot air near the Earth’s surface bends light rays upward. In a desert, the effect prompts lost travelers to mistake patches of blue sky for pools of water. But another kind of mirage occurs when cold air bends light rays downward. In that case, observers can see objects and settings far over the horizon. The images often undergo quick distortions — not unlike the wavy reflections in a funhouse mirror.
Now, scholars of the Titanic are debating these new theories. Some have different opinions on it. Over all, though, many experts are applauding the fresh perspectives.
1.The underlined word "It" in the title probably refers to _______.
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A．the Titanic |
B．the cause of the disaster |
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C．the record tide |
D．an unusual mirage |
2.According to Theory First, what was the right chain of causes leading to the Titanic’s disaster?
① record tides’ forming and icebergs’ being refloated
② icebergs’ being drifted into the North Atlantic shipping lanes
③ the Earth’s strange closing to the Sun and the Moon
④ increasing of the gravitational force on the ocean
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A．①→②→③→④ |
B．②→③→④→① |
C．④→③→②→① |
D．③→④→①→② |
3.According to Theory Second, the disaster happened to the Titanic mainly because______.
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A．the freezing weather made the watcher not be able to watch clear |
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B．the mirage made the watcher not find icebergs and a nearby ship delay rescuing |
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C．the mirage on the sea attracted the watcher and made him forget his work |
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D．the high tides drove the icebergs float so fast that the watcher didn’t respond to them |
4.What is the chief function of the sixth paragraph?
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A．to explain to the readers the ways of the mirage forming |
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B．to infer the possibility of the mirage appearing |
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C．to summarize the various kinds of the mirage |
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D．to analyze the conditions of the mirage arising |
5.This passage is organized generally in the pattern of________.
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A．comparison and contrast |
B．conclusion and proof |
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C．time and events |
D．definition and classification（分类) |