Continental Drift Is Happening

Continental drift is happening. Discuss the evidence

Continental drift is defined as the gradual movement of continents across the Earths surface through geological time. As early as 1620, Francis Bacon noted the jigsaw-like fit between the east coast of South America and the west coast of Africa. However, it was in 1912 when a German meteorologist, Alfred Wegener, published his theory that all the continents were once joined together in one large supercontinent, which was named Pangaea. Wegeners theory of continental drift combined information from several subject areas, examples include: maps, biology, geology and climatology. Be that as it may, specialists in those disciplines rejected his ideas partly because he was not regarded as an expert himself, but mainly because he could explain how solid continents had changed their position.

[pic 1]The first piece of evidence that really inspired Wegners quest to explain Earths geology was a map of the continents that showed the interlocking fit of Africa’s and South Americas shoreline. Using these maps, Wegener then questioned as to why these coastlines fitted so precisely. He came up with the theory that in the remote past (200 million years ago) they were part of a larger super continent (Pangaea) that then spilt apart via sub-oceanic forces which sent the landmasses wandering around the globe. Here is a picture that shows how all of the continents perfectly fit into each other.

From looking at these maps it led Wegener to predict that if these coastlines were connected, then the geology at the corresponding positions along the coastline should correlate. As a result of this prediction, Wegener began to study the stratigraphy of different rocks and mountain ranges, again looking more specifically at the east coast of South America and the west coast of Africa seemingly he discovered that the rock layers ‘fitted’ just as clearly as the maps had previously showed. With both coastlines showing that the oldest layers of rock were granite, then slate and finally it was sandstone. However, the final two layers of the coastline were different, but this is because a lot has changed in the 80million years that they have been separated. Moreover, South America and Africa weren’t the only continents with similar geology. Wegener discovered that the Appalachian Mountains of eastern United States were geologically related to the Caledonian Mountains in Scotland as well as the Appalachian Mountains being nearly identical to the Atlas Mountains of Morocco, because the same process formed them when they were part of the same chain.[pic 2]

After looking at the geology of the different coastlines, Wegener began to look at fossilized plants and animals to further support his claim of Continental drift. Again he began to look at two different coastlines of two different continents to see if any of the same fossils could be found. He decided to inspect the fossil of the ancient reptile mesosaurus, a freshwater reptile only one metre (3.3feet) long that could only be found in southern Africa and South America. As a result of the two continents being separated by the Atlantic, it somewhat proved that these animals could not of been able to swim across, but in fact suggested that they were once from a single habitat with many lakes and rivers, adding credence to the belief that Africa and South America were connected 270 million years agon when the Mesosaurus roamed the Earth