2. 外语
  3. The coastlines on the two sides of the Atlantic Ocean present a notable parallelism: the easternmost region of Brazil, in Pernam

The coastlines on the two sides of the Atlantic Ocean present a notable parallelism: the easternmost region of Brazil, in Pernam

admin2011-03-26  47
问题     The coastlines on the two sides of the Atlantic Ocean present a notable parallelism: the easternmost region of Brazil, in Pernambuco, has a convexity that corresponds almost perfectly with the concavity of the African Gulf of Guinea, while the contours of the African coastline between Rio de Oro and Liberia would, by the same approximation, match those of the Caribbean Sea.
    Similar correspondences are also observed in many other regions of the earth. This observation began to awaken scientific interest about sixty years ago, when Alfred Wegener, a professor at the University of Hamburg, used it as a basis for formulating a revolutionary theory in geological science.  According to Wegener, there was originally only one continent or landmass, which he called Pangea. Inasmuch as continental masses are lighter than tile base on which they rest, he reasoned, they must float on the substratum of igneous rock, known as sima, as ice floes float on the sea. Then why, he asked, might continents not be subject to drifting? The rotation of the globe and other forces, he thought, had caused the cracking and, finally, the breaking apart of the original Pangea, along an extensive line represented today by the longitudinal submerged mountain range in the center of the Atlantic. While Africa seems to have remained static, the Americas apparently drifted toward the west until they reached their present position after more than 100 million years. Although the phenomenon seems fantastic, accustomed as we are to the concept of the rigidity and immobility of the continents, on the basis of the distance that separates them it is possible to calculate that the continental drift would have been no greater than two inches per year.
Professor Wegener’s theory is ______.
选项 A、an attempt to explain many geographical parallelisms
B、based on a study of 100 years
C、an analysis of the lost continent
D、unsound
答案A
解析 韦格纳教授的理论试图解释地理学方面的许多相似性。文章的第一段和第二段提出了地理学方面的许多相似性，文章的第二段指出，韦格纳教授提出了一种革命性的理论，试图解释地理学方面的许多相似性。
转载请注明原文地址:https://www.kaotiyun.com/show/ZYBO777K
0

考博英语

相关试题推荐
随机试题
最新回复(0)