geography- seismic activity
“Volcanic and seismic events are major pieces of evidence towards proving that the plate tectonics theory is valid” Discuss the extent to which you agree with this statement (40m)
The theory of plate tectonics explains the structure and motion of the Earth’s lithosphere. The theory states that the Earth’s crust is split into large sections called tectonic plates, and these move relative to one another creating boundaries at which the plates converge, diverge or move past each other. These plates are either continental or oceanic and are powered by convection currents, which is the circular movement of magma that comes from within the mantle. These currents are powered by the core, which heats the magma, causing it to rise, cool and fall back down. This circular motion causes the plates, which float on the mantle, to move. In 1912, Alfred Wegener, was the first man to state that the continents were once joined in a continent called Pangaea, but he couldn’t explain why and what happened to cause the plates to move apart so at the time the theory wasn’t believed. He based his theory on the fit of the South American and African continent coastlines. Notably the eastern edge of South America and the western edge of Africa showed very similar geological features suggesting that at some point in the Earth’s history the landmasses were joined together. It is only since the 1950s where palaeogmagnetism and the exploration of sea floor spreading that Wegner’s theory was believed. Evidence to support this theory is that there is that there have been fossils found on both sides of the Atlantic Ocean of land animals for example Mesosaurus and Glassopteris which suggests that the two land masses must have been together originally. There is also climate evidence for this as there is coal deposits and fern fossils in the Antarctica which shows it used to be more equatorial. Glacial evidence is that in both South America and Africa there are sedimentary deposits of angular,
The theory of plate tectonics explains the structure and motion of the Earth’s lithosphere. The theory states that the Earth’s crust is split into large sections called tectonic plates, and these move relative to one another creating boundaries at which the plates converge, diverge or move past each other. These plates are either continental or oceanic and are powered by convection currents, which is the circular movement of magma that comes from within the mantle. These currents are powered by the core, which heats the magma, causing it to rise, cool and fall back down. This circular motion causes the plates, which float on the mantle, to move. In 1912, Alfred Wegener, was the first man to state that the continents were once joined in a continent called Pangaea, but he couldn’t explain why and what happened to cause the plates to move apart so at the time the theory wasn’t believed. He based his theory on the fit of the South American and African continent coastlines. Notably the eastern edge of South America and the western edge of Africa showed very similar geological features suggesting that at some point in the Earth’s history the landmasses were joined together. It is only since the 1950s where palaeogmagnetism and the exploration of sea floor spreading that Wegner’s theory was believed. Evidence to support this theory is that there is that there have been fossils found on both sides of the Atlantic Ocean of land animals for example Mesosaurus and Glassopteris which suggests that the two land masses must have been together originally. There is also climate evidence for this as there is coal deposits and fern fossils in the Antarctica which shows it used to be more equatorial. Glacial evidence is that in both South America and Africa there are sedimentary deposits of angular,