求助：GWD1-Q6

Prior to 1965 geologists assumed

that the two giant rock plates meeting at

the San Andreas Fault generate heat

Linethrough 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.

Q6:

The passage mostly agree that Heney’s findings about temperature in the San Andreas Fault made the greatest contribution in that they

A. revealed an error in previous measurements of temperature in the San Andreas Fault zone

B. indicated the types of clay present in the rocks that form the San Andreas Fault

C. established the superiority of a particular technique for evaluating data concerning friction in the San Andreas Fault

D. suggested that geologists had inaccurately assumed that giant rock plates that meet at the San Andreas Fault generate heat through friction

E. confirmed geologists’ assumptions about the amount of friction generated by common varieties of rocks, such as limestone and granite