plate tectonic essay

Submitted By suzanna5276
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Pages: 4

Plate Tectonics Essay

W. Jacqueline Kious and Robert I. Tilling, wrote a book titled “This Dynamic Earth: The story of Plate Tectonic”. It tells us information of people who have explore the world, their discoveries that developed the theory of plate tectonic and how it has progressed through the years. Plate Tectonics is how the Earth’s surface is built of plates. The scientific theory of plate tectonics is that the movements of the large sections form the Earth’s surface. Plate Tectonics has help scientists understand the Earth, by studying fossils, to the studying of other geologic concepts and principles. The Earth has been around for years and so scientists, philosophers, and theologians have many questions that still needed to be answered.
Plate tectonics is now accepted, but it took a long time for it to be accepted. There scholars who were fascinated by the similarities of Africa and South America. Alfred Lothar Wegener introduced his theory of continental drift. The theory was going to show why there were similarities in Africa and South America. He noticed when he was look at geological maps, that Africa and South America had a similarity in rock types, mostly in the southern parts. He found mineral deposits, and fossils, in many countries. Wegner believed that the supercontinent “Pangaea” began to split apart. However, Toit, thought that the Pangaea first broke into two big continental landmasses.” Laurasia” was the Northern Hemisphere and “Gondwanaland” in the Southern Hemisphere. These two big pieces soon began to break into smaller continents. Wegener also thought that the presence of fossil species along the coastal parts of South America and Africa were evidence that proved that the two continents were once connected. In his mind, the fossils also meant that there could have been climate changes on some of the continents. The scientific community did not received Wegener’s theory that well. An English geophysicist, Harold Jeffrey’s argued that it was not possible for the large continents to move, without separating. Wegner still stuck to his theory, even after he died in 1930 on an expedition through the Greenland ice cap. There was soon new evidence that help supported Wegner’s theory and led to the development of the theory of plate tectonics. Plate tectonics is still being studied today.
A question that scientists had were what drove the plates? The scientists believe in the 1930s, that Harry Hess Theory explains why the plates move. He believed that the plates moved by the “slow movement of hot, softened mantle that lies below the rigid plates.” J. Tuzo Wilson found that the Earth’s surface and its interior both were moving. The rock beneath the ridged plates move in a circular motion. The heat rises up and as it spreads, it begins to cool. It will then go back to the bottom and the heat will go back up again. This is called a convective flow, and is always repeated.