Prior to 1965 geologists assumed that the two giant rock plates meeting at the San Andreas Fault generate heat through friction as they grind past each other, but in 1965 Henry found that temperatures in drill holes near the fault were not as elevated as had been expected. Some geologists wondered whether the absence of friction-generated heat could be explained by the kinds of rock composing the fault. Geologists’ pre-1965 assumptions concerning heat generated in the fault were based on 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 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 10 to 15 kilometers below the Earth’s surface. Byerlee found that when clay samples were subjected to the thousands of atmospheres of pressure they would encounter deep inside the 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 rocks’ properties, affects frictional heating. Geologists therefore wondered 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.
文章首先提出一个猜想,然后Henry发现了意想不到的现象,然后是地理学家提出猜想去解释这一现象。
选项A evaluating a method 文章并不是有 提出一个方法,然后去评估这个方法 的文章结构
选项B 正确 发现,提出猜想解释发现
选项C 在一个实验的基础上examining the assumptions, 猜想,检测猜想,是文章中的一个部分,与B相比不全
选项D 并不是去质疑finding的可靠性,而是去解释这一发现
选项E 并没有present 一些evidence去支持现在的一个猜想,
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