Continental drift is the idea that the earth’s continents are drifting away, relative to each other across the ocean bed suggested by Alfred Wegner as part of his wider theory on plate tectonics. The plate tectonic theory suggested by Alfred Wegner in 1915 was that millions of years ago all the continents were joined together in one mass of land called ‘Pangaea’, the evidence for this was that coal was found on Antarctica, the shape of Africa and south America fit together and same fossils were found on different continents. This theory is used to explain the distribution of earthquakes, volcanoes and Fold Mountains, it states that the earth’s core consists of semi molten magma and the earth’s surface or crust sits on top of the magma and moves to heat produced by the decay of radioactive isotopes and friction in the core. It is at the boundaries of these ‘plates’ where we find evidence for the idea of plate tectonic theory. Here many features are formed such as volcanoes and Fold Mountains, earthquakes are less visible but are still processes which support continental drift and plate tectonics.
There are 5 different types of plate boundaries where the plates meet, move apart or rub along that provide processes and features that support continental drift and therefore plate tectonics. Volcanoes are a main feature at most plate boundaries as they come from magma chambers below the earths surface predominantly from melting plates. Other features include earthquakes, ocean trenches, mid ocean ridges and fold mountains. At all these different boundaries many processes occur at or around them. Firstly there is constructive this is where the two plates are moving apart this is normally in boundaries between two oceanic plates creating a lava upwelling from below, this causes oceanic ridges such as the mid Atlantic ridge, the two plates can be moving apart at either a slow, intermediate or rapid rate. Here not many processes take place a the plates are not...
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