GWD 24-33

yukon

楼上，我也不知道如何定位，因为我有一些地质的基础知识，一口气读下来没回头找了

帮你解释一下吧，P波和S波由一个震源产生，但速度不同，就像打雷一样：闪电和雷声得间隔越大，说明放电点离地面越远，排除AB；还有就是影响面积的问题：Most earthquakes had a small area of intense shaking, which weakened rapidly with increasing distance from the epicenter, but others were characterized by a lower peak intensity, felt over a broader area这句话可以说明，就像你拿个手电筒往远处照，照得越远，光束就越分散，地震能量也是如此。

33题

第一段里：Some earthquakes, however, take place hundreds of kilometers down in the Earth’s mantle, where high pressure makes rock so ductile that it flows instead of cracking, even under stress severe enough to deform it like putty.

可以看出有些地震的结局是流动形变（flows)而不是脆裂啊（cracking)

请牛牛回答！

ygh01

这篇文章和大全

Passage 79 (16/22)

是一样的,请参考.

carcar

以下是引用yukon在2005-7-24 10:34:00的发言：

楼上，我也不知道如何定位，因为我有一些地质的基础知识，一口气读下来没回头找了

帮你解释一下吧，P波和S波由一个震源产生，但速度不同，就像打雷一样：闪电和雷声得间隔越大，说明放电点离地面越远，排除AB；还有就是影响面积的问题：Most earthquakes had a small area of intense shaking, which weakened rapidly with increasing distance from the epicenter, but others were characterized by a lower peak intensity, felt over a broader area这句话可以说明，就像你拿个手电筒往远处照，照得越远，光束就越分散，地震能量也是如此。

33题

第一段里：Some earthquakes, however, take place hundreds of kilometers down in the Earth’s mantle, where high pressure makes rock so ductile that it flows instead of cracking, even under stress severe enough to deform it like putty.

可以看出有些地震的结局是流动形变（flows)而不是脆裂啊（cracking)

请牛牛回答！

The descending rock is substantially cooler than the surrounding mantle and hence is less ductile and much more liable to fracture.

这是文章最后一句。。说明还是fracture了。。

carcar

以下是引用Melissa99在2005-5-17 8:11:00的发言：

24-31 Information presented in the passage suggests that, compared with seismic activity at the epicenter of a shallow event, seismic activity at the epicenter of a deep event is characterized by

A) shorter P-S intervals and higher peak intensity

B) shorter P-S intervals and lower peak intensity

C) longer P-S intervals and similar peak intensity

D) longer P-S intervals and higher peak intensity

E) longer P-S intervals and lower peak intensity

应该如何定位呢？

That such deep events do occur has been accepted only since 1927, when the seismologist Kiyoo Wadati convincingly demonstrated their existence. Instead of comparing the arrival times of seismic waves at different locations, as earlier researchers had done, Wadati relied on a time difference between the arrival of primary (P) waves and the slower secondary (S) waves. Because P and S waves travel at different but fairly constant speeds, the interval between their arrivals increases in proportion to the distance from the earthquake focus, or initial rupture point. For most earthquakes, Wadati discovered, the interval was quite short near the epicenter; the point on the surface where shaking is strongest. For a few events, however, the delay was long even at the epicenter. Wadati saw a similar pattern when he analyzed data on the intensity of shaking. Most earthquakes had a small area of intense shaking, which weakened rapidly with increasing distance from the epicenter, but others were characterized by a lower peak intensity, felt over a broader area. Both the P-S intervals and the intensity patterns suggested two kinds of earthquakes: the more (45) common shallow events, in which the focus lay just under the epicenter, and deep events, with focus several hundred kilometers down.

红字处

monabluestone

此篇阅读十分bt,很鄙视

duanrt

我以前也学过地质，这篇文章读得也很快，一道题都没有错。其实前面yukon已经解释很清楚了。

MaccMichAA

...

加拿大帅哥

ETS 还说不靠专业知识，看的我晕晕的，懂得地质的人一口气看完，还不用回头。

 

SuccessMBA08

以下是引用yukon在2005-7-24 10:34:00的发言：

楼上，我也不知道如何定位，因为我有一些地质的基础知识，一口气读下来没回头找了

帮你解释一下吧，P波和S波由一个震源产生，但速度不同，就像打雷一样：闪电和雷声得间隔越大，说明放电点离地面越远，排除AB；还有就是影响面积的问题：Most earthquakes had a small area of intense shaking, which weakened rapidly with increasing distance from the epicenter, but others were characterized by a lower peak intensity, felt over a broader area这句话可以说明，就像你拿个手电筒往远处照，照得越远，光束就越分散，地震能量也是如此。

33题

第一段里：Some earthquakes, however, take place hundreds of kilometers down in the Earth’s mantle, where high pressure makes rock so ductile that it flows instead of cracking, even under stress severe enough to deform it like putty.
            

可以看出有些地震的结局是流动形变（flows)而不是脆裂啊（cracking)

请牛牛回

举例精辟，不亏是学过地质学的！

true

   

如果33题选D的话，那么不就和35题矛盾了么？

GWD-24-33.

The passage suggests that which of the following must take place inorder for any earthquake to occur?

1. Stress must build up.

2. Cool rock must descend into the mantle.

3. A fracture must occur

A.     1 only

B.      2 only

C.      3 only

D.     1 and 3 only

E.       1, 2, and 3

D is the correct answer.

Q35：The author uses the comparisons toporcelain and putty (lines 2 and 8) in order to

A.      explain why the Earth’smantle is under great pressure

B.      distinguish theearthquake’s epicenter from its focus

C.      demonstrate theconditions under which a Wadati-Benioff zone forms

D.      explain why S waves areslower than P waves

E.      illustrate why the crust will fracture but themantle will not

E is the correct answer.