GWD-12-Q25

stevenckguo

GWD-12-Q24 to Q27:

    Years before theadvent of plate tectonics―the widely accepted theory, developed in themid-1960’s, the holds that the major features of Earth’s surface are created bythe horizontal motions of Earth’s outer shell, or lithosphere ―a similar theorywas rejected by the geological community. In 1912, Alfred Wegener proposed, in a widely debated theory that cameto be called continental drift, that Earth’s continents were mobile. To most geologists today, Wegener’s The origin of Continents and Oceans appearsan impressive and prescient document, containing several of the essentialpresumptions underlying plate tectonics theory: the horizontal mobility ofpieces of Earth’s crust; the essential difference between oceanic and continentalcrust; and a causal connection between horizontal displacements and theformation of mountain chains.  Yet despitethe considerable overlap between Wegener’s concepts and the later widelyembraced plate tectonics theory, and despite the fact that continental drifttheory presented a possible solution to the problem of the origin of mountainsat a time when existing explanations were seriously in doubt, in its dayWegener’s theory was rejected by the vast majority of geologists.
      Mostgeologists and many historians today believe that Wegener’s theory was rejectedbecause of its lack of an adequate mechanical basis.  Stephen Jay Gould, for example, argues that continentaldrift theory was rejected because it did not explain how continents could movethrough 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 explained.  The most likely cause for the rejectionof continental drift ―a cause that has been largely ignored because we considerWegener’s theory to have been validated by the theory of plate tectonics―is thenature of the evidence that was put forward to support it.  Most of Wegener’s evidence consisted ofhomologies—similarities of patterns and forms based on direct observations of rocksin the field, supported by the use of hammers, hand lenses, and field notebooks.  In contrast, the data supporting platetectonics were impressively geophysical—instrumental determinations of the physicalproperties of Earth garnered through the use of seismographs, magnetometers,and computers.


Q25:
Theauthor of the passage refers to the “considerable overlap” (line 23) betweencontinental drift theory and plate tectonics theory most probably in order to


A.    suggestthat plate tectonics theory is derived from Wegener’s work
B.     introducea discussion comparing the elements of the two theories
C.    examinethe question of whether continental drift theory was innovative in its time
D.    providea reason why it might seem surprising that continental drift theory was notmore widely embraced by geologists
E.     cite anexplanation that has been frequently offered for Wegener’s high standing amonggeologists today

OA is D, BUT I still think of A.  Can someone tell me the reason of D?

xinxiangwei

despite overlap很大..........in its day Wegener’s theory was rejected by the vast majority of geologists.

EvaCheng

D正确。


我感觉是这样的：


Tomost geologists today, Wegener’s The origin of Continents and Oceans appears an impressive and prescient document,containing several of the essential presumptions underlying plate tectonicstheory: the horizontal mobility of pieces of Earth’s crust; the essential differencebetween oceanic and continental crust; and a causal connection betweenhorizontal displacements and the formation of mountain chains. Yet despite the considerable overlap between Wegener’sconcepts and the later widely embraced plate tectonics theory, and despite thefact that continental drift theory presented a possible solution to the problemof the origin of mountains at a time when existing explanations were seriouslyin doubt, in its day Wegener’s theory was rejected by the vast majority ofgeologists.

文章的浅粉色部分说，对于今天的地理学家来说，Wegener的著作The origin of Continents and Oceans是impressive and prescient的，细细体味这两个词，其实有“哇，他竟然在那N年前就已经写出了这本书”的意思。然后浅绿色部分详细说明了为什么今人觉得他的著作是有先见之明的，具体体现在他提出的essential presumptions与今人推崇的tectonics theory吻合。（但是这里没有说明后来的tectonics theory就是建立在这些presumptions上的，所以我觉得A不对。）然后作者话锋一转，说虽然Wegener的著作跟后人的tectonics theory有重叠，虽然在当时各种解释都很不合理的情况下，大陆漂移理论给山的起源问题提供了可能的解释，Wegener的理论还是没有被当时的地理学家所接受。


所以站在作者的立场说，当时那些地理学家不接受Wegener的理论是十分surprising的，因为后人证实这个理论是正确的（第一个虽然，也就是黄色高亮部分，考点），并且因为当时没有其他更好的理论来解释这个问题（第二个虽然）。选项D正确。