You’d think that if the San Andreas Fault went to the trouble of having a perfectly good earthquake, the folks on the US West Co

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问题     You’d think that if the San Andreas Fault went to the trouble of having a perfectly good earthquake, the folks on the US West Coast might at least notice. A new study reveals, however, that in 1992, what should have been a China-smashing 4.8 Richter-scale quake hit central California, and yet nobody felt a thing. The explanation for the odd shadow-quake was published last week in the journal Nature and may help improve science’s understanding of earthquakes in general.
    According to Alan T. Linda, a geophysicist at the Carnegie Institution of Washington and the study’s leader, what makes seismic events so destructive is not just that the earth moves but the speed with which it does so. In many quakes the earth’s surface movement that leads to shaking takes only seconds to unfold, sending energy exploding in all directions. But recent analysis of data from strain gauges along the San Andreas Fault reveals that four years ago, a skip occurred that took a week to play out. Such slow sliding almost eliminates an earthquake’s quaking.
    Exactly what determines the speed with which the earth’s plates move is unclear, but scientists have some ideas. "The fault material may play a role," Linda says, "Rock with holes containing water can move more smoothly than other rock. The pressure the plates are under can make a difference too: the bigher the stress, the likelier the fault will fail suddenly."
    Linda’s work may never help seismologists determine which type of temblor is likely to strike which region, but he still believes the research has value. There may be no better way of understanding destructive quakes, he feels, than to learn what makes them less destructive.  
Which of the following statements is NOT true?

选项 A、Slow sliding of the San Andreas eliminates an earthquake’s quaking.
B、Rock with holes can move more smoothly than other rock.
C、What determines the speed with which the earth’s plates move is unclear.
D、Linda’s study helps seismologists determine the type of temblor.

答案D

解析 第二段“Such slow sliding almost eliminates an earthquake’s quaking.”证明A 是正确论述。第三段“Rock with holes containing water can move more smoothly than other rock.”说明B是正确论述。“Exactly what determines the speed with which the earth’s plates move is unclear, but scientists have some ideas.”说明C是正确论述。最后一段“Linda’s work may never help seismologists determine which type of temblor is likely to strike which region.” 说明D是错误论述。
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