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[GMAT阅读题讨论] PREP2012阅读第7篇第1题

icetong123 发表于 2015-1-9 11:17:56 | 显示全部楼层 |阅读模式
Years before the advent of plate tectonics—the widely accepted theory, developed in the
mid-1960s, that holds that the major features of Earth's surface are created by the horizontal
motions of Earth's outer shell, or lithosphere—a similar theory was rejected by the geological
community. In 1912, Alfred Wegener proposed, in a widely debated theory that came to be
called continental drift, that Earth's continents were mobile. To most geologists today,
Wegener’s The Origin of Continents and Oceans appears an impressive and prescient
document, containing several of the essential presumptions underlying plate tectonics theory:
the horizontal mobility of pieces of Earth's crust; the essential difference between oceanic
and continental crust; and a causal connection between horizontal displacements and the
formation of mountain chains. Yet despite the considerable overlap between Wegener’s
concepts and the later widely embraced plate tectonics theory, and despite the fact that
continental drift theory presented a possible solution to the problem of the origin of
mountains at a time when existing explanations were seriously in doubt, in its day Wegener’s
theory was rejected by the vast majority of geologists.
Most geologists and many historians today believe that Wegener's theory was rejected
because of its lack of an adequate mechanical basis. Stephen Jay Gould, for example, argues
that continental drift theory was rejected because it did not explain how continents could
move through an apparently oceanic floor. However, as Anthony Hallam has pointed out,
many scientific phenomena, such as the ice ages, have been accepted before they could be
fully explained.The most likely cause for the rejection of continental drift—a cause that has
been largely ignored because we consider Wegener's theory to have been validated by the
theory of plate tectonics—is the nature of the evidence that was put forward to support it.
Most of Wegener's evidence consisted of homol0gies—similarities of patterns and forms
based on direct observations of rocks in the field, supported by the use of hammers, hand
lenses, and field notebooks. In contrast, the data supporting plate tectonics were
impressively geophysical—instrumental| determinations of the physical properties of Earth
garnered through the use of seismographs, magnetometers, and computers.

It can be inferred from the passage that geologists today would be most likely to agree with
which of the following statements about Wegener's The Origin of Continents and Oceans?
A. It was a worthy scientific effort that was ahead of its time.
B. It was based on evidence that was later disproved.
C. It was directly responsible for the acceptance of the theory of plate tectonics.
D. It has been disproved by continental drift theory.
E. It misrepresented how horizontal displacements cause the formation of mountain chains.




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