“What evidence is there to support Alfred Wegener’s theory of continental drift?

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“What evidence is there to support Alfred Wegener’s theory of continental drift?"

Alfred Wegener, born November 1st 1880, was a German scientist who took a great interest in meteorology and paleoclimatology and in 1905 graduated from the University of Berlin with a Ph.D. in Astronomy. His most notable work was the theory of continental drift. However his theory was highly controversial at the time as he had little evidence, but as technology enhanced neumerous discoveries were made which helped prove his idea of continental drift was true.

In 1912, Wegener published this theory that a single continent existed about 300 million years ago. He named his super-continent Pangaea, and maintained that it had later split into the two continents of Laurasia in the north and Gondwanaland in the south. Today’s continents were formed from further splitting of these two masses. Wegener published this theory of continental drift and claimed that it was supported by several pieces of evidence and that these areas were once joined. Although Abriham Ortelius previously proposed the idea of continents ‘drifting’ Wegener had thought it through in greater detail. He started gathering evidence and found that they fell into three categories, geological, biological and climatological. Wegener noticed the way in which continents such as South America and Africa appear to fit’ together, especially when the edge of the continental shelf is used rather than the present coastline, suggesting that they may have once been joined together – this is also known as the ‘jigsaw fit’. The diagram shows the break-up of the super-continent Pangaea, which figured prominently in the theory of continental drift -- the forerunner to the theory of plate 

Wegener also noticed a link between the rock types and geological structures that were seen to be similar on the two sides of the Atlantic. Such as the Appalachian Mountains in North America and the Caledonian Mountains in Scotland which have the same sequence of igneous and sedimentary rocks, suggesting that they were formed at the same time and in the same place. Other evidence Wegener used to help back to his thesis was that there is evidence of glaciations during the late Carboniferous period 290 million years ago, where striations on rocks left from the ice age were found in South America, Antarctica and India further supporting that they must have been formed together then moved apart. Wegener’s biological evidence was found from some fossils such as that of the Mesosaurus, a small freshwater reptile, which can be found in both southwest Africa and Brazil. Another fossil was of a small fern, Glossopteris, which were found widely across all southern continents, also suggesting that the landmasses were once joined and such creatures and plants lived in the whole combined area. Climatological evidence found referred to coal and oil reserves found in Antarctica that suggests that this area was once in a different climatic zone in order for this process to have occurred. In this diagram it shows Wegeners idea of how the continents must have been together due to the same fossils being found on different continents around the world.

At the time when Wegener proposed his theory he was widely ridiculed for them because he did not have sufficient evidence to completely prove his theory and due to this many scientists didn’t believe him. Also Wegener wasn’t an official geologist, he was a professor who taught at the University of Marburg in Germany, therefore many people did not take him as a reliable source. Moreover, people in society at the time didn’t believe in Wegener’s theories due to religious beliefs in the early 1900’s, believing that god had created the earth in 6 days, so were therefore stubborn to change particularly as the evidence was insufficient. Another reason why Wegener’s theory was not accepted was that Wegener suggested that the mechanism for the movements of the continents...
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