gwd-1-4

daisy1980626

Prior to 1965 geologists assumed

       that the two giant rock plates meeting at

       the San Andreas Fault generate heat

Line
                through friction as they grind past each

  (5)      other, but in 1965 Henyey found that

temperatures in drill holes near the

fault were not as elevated as had

been expected.  Some geologists

wondered whether the absence of

 (10)      friction-generated heat could be

explained by the kinds of rock com-

posing the fault.  Geologists’ pre-1965

assumptions concerning heat gen-

erated in the fault were based on

 (15)      calculations about common varieties of

rocks, such as limestone and granite;

but “weaker” materials, such as clays,

had already been identified in samples

retrieved from the fault zone.  Under

 (20)      normal conditions, rocks composed of

       clay produce far less friction than do

       other rock types.

       In 1992 Byerlee tested whether

these materials would produce friction

 (25)      10 to 15 kilometers below the Earth’s

surface.  Byerlee found that when clay

samples were subjected to the thou-

sands of atmospheres of pressure

they would encounter deep inside the

 (30)      Earth, they produced as much friction

as was produced by other rock types.

The harder rocks push against each

       other, the hotter they become; in other

words, pressure itself, not only the

 (35)      rocks’ properties, affects frictional

heating.  Geologists therefore won-

dered whether the friction between the

plates was being reduced by pockets

of pressurized water within the fault that

push the plates away from each other.

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Q4:

The passage suggests which of the following regarding Henyey’s findings about temperature in the San Andreas Fault?

             

1. Scientists have yet to formulate a definitive explanation for Henyey’s findings.
2. Recent research suggests that Henyey’s explanation for the findings should be modified.
3. Henyey’s findings had to be recalculated in light of Byerlee’s 1992 experiment.
4. Henyey’s findings provided support for an assumption long held by geologists.
5. Scientists have been unable to duplicate Henyey’s findings using more recent experimental methods.

我选的B，答案是A, 请NN指教啊。还想问一下，我在CD阅读专区搜索GWD-1-4,但是出来的不是这道题，怎么样可以直接搜到这道题呢，补充一下，我这个是Taotao31套。