Continental Drift

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Tectonics and Continental Drift Past and Present Locations

Abstract
When we look at our earth’s surface now it has seven continents, and five of them are divided by the oceans that surround them. In 1912 Alfred Wegner (1880-1930), came up with a theory called the continental drift; stating that over three hundred years ago all seven continents were once one super continent called Pangaea. Wegner tried to convince other scientists and geologist for many years that the continents drifted apart; however he didn’t have the geological mechanism that was needed to validate his theory. Throughout his search he did find a paleontological paper that signified that there was a land bridge connecting Africa and Brazil. The geographic evidence that prove that the continents drifted apart is; by the large ocean ridges that were formed by molten material that has risen from the earth, it is the molten material to be believed the reason for the continents drifting apart. The recognizable reason would be how the continents fit perfectly together like a puzzle, and the many fossils and rocks were found on the coastlines that would not have been able to exist in the areas they were found, pointing to the continents drifting apart. It wasn’t until 1950’ when scientist’s verified that there was paleomagnetic evidence that supported Wagner’s theory on the continental drift, and why the continents drifted apart; unfortunately Alfred Wegner had passed away in 1930 when he was on a dogsled excursion in Greenland, and he died knowing that his theory wasn’t believed by many people. (BookRags)

Tectonics and Continental Drift Past and Present Locations
Alfred Wagner an adept investigator, spent most of his life trying to convince geologists of his theory called the continental drift. He found some documentation that there was a land bridge that connected Brazil and Africa and he tried to explain the fossilized animals and plants that were found in Africa and South America; North America and Europe; India and Madagascar, all came from the same time period, and there would have been impossible for these creatures and plants to travel across the Oceans that we have now. Wagner also claims that there were Striae left by glaciers over land, proving that continental glaciation took place in the Pennsylvanian era. There is an indication that South Africa, and South America, were close together and South America, and Africa were also close together, during the ancient ice age. Wagner also explained his Contraction theory for the mountain formation, he was proposing that there was a molten ball and that when it cooled the surface it cracked and folded making the mountains form the way they did, and that as the continents drifted that the mountains that were formed due to resistance causing them to contract and move upward. Mountains on the Pacific coast of North America, The Sierra Nevada, and Andes on the coast of South America were cited.  Wegener indicated that India coasted northward into the Asian continent that formed the Himalayas. (Weil, 1997) Wegner claimed that the rotation of the earth caused a centrifugal dynamism in the direction of the equator; he claimed that Pangaea was originally close to the South Pole he proposed centrifugal dynamism causing the continents to break away and the subsequent continents to move in the direction of the equator. He named this "pole-fleeing force". Wegner also purposed that the Americas moving west was caused by gravity forces from the moon and sun (Weil, 1997) because Wegner was not able to validate his theories ended in scientific dismissal. Arthur Holmes expounded in 1929, one of Wegner’s theories that mantle undergoes thermal convection which is when a substance is heated that substance concentration decreases, and rises to the top of the surface and then when it cools down it goes back down again if the process continues to be repeated thus causing the currents to be enough to be the...
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