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Q24 to Q27:
Years before the advent of plate
tectonics―the widely accepted theory,
developed in the mid-1960’s, the holds
Line that the major features of Earth’s surface
(5) 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
(10) 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
(15) 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 conti-
(20) nental 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
(25) later widely embraced plate tectonics
theory, and despite the fact that conti-
nental drift theory presented a possible
solution to the problem of the origin of
mountains at a time when existing expla-
(30) nations 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
(35) 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
(40) could move through an apparently solid
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
(45) 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
(50) tectonics―is the nature of the evidence
that was put forward to support it. Most
of Wegener’s evidence consisted of
homologies—similarities of patterns and
forms based on direct observations of
(55) rocks in the field, supported by the use
of hammers, hand lenses, and field note-
books. In contrast, the data supporting
plate tectonics were impressively
geophysical—instrumental determinations
(60) of the physical properties of Earth gar-
nered through the use of seismographs,
magnetometers, and computers.
Q26:
The author of the passage suggests that the most likely explanation for the geological community’s response to continental drift theory in its day was that the theory
was in conflict with certain aspects of plate tectonics theory
failed to account for how mountains were formed
did not adequately explain how continents moved through the ocean floor
was contradicted by the geophysical data of the time
was based on a kind of evidence that was considered insufficiently convincing
答案是E，但是我觉得应该是C啊？
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发表于 2004-10-23 00:52:00
