Essay On Continental Drifting

More than 170 million years ago all of the continents formed a single landmass, called Pangaea. Around this time a period of rifting commenced, breaking up Pangaea, forming super-continents and opening vast new oceans. This was the beginning of continental drifting. Continental drifting is an interesting natural occurrence and such immense shifting can lead to earthquakes, which in turn can lead to tsunamis (McCarthy and Rubidge, 2005).

Evidence of the movement of continents was first found in the 1950s and 1960s, in a north-south direction, during geological time. Continents had also undergone relative motions and this is known as continental drifting. The movement of these continents across the surface of the Earth can be because of its pole and angle of rotation (Keary and Vine, 1996). The tectonic plates, plates that Earth’s outer shell is composed of, move around constantly on a hot layer of rock called the asthenosphere (Ochoa, 2007). The cold lithosphere descends at subduction zones [explain]. This happens because of the lithosphere being denser than the asthenosphere and results in plate motions/ convection currents, and movement is made possible by the slippery layer of the asthenosphere. This is known as the theory of plate tectonics (McCarthy and Rubidge, 2005). Continental drifting results in the breaking and assembling of continents, the raising of mountain ranges and volcanic islands, and the opening of rifts and creation of ridges and trenches. The most dramatic evidence of plate movement are provided by earthquakes and associated tsunamis (also known as sea-quakes). They are located on the boundaries of moving plates (Ochoa, 2007; Norma and Whitfield, 2006).

Earthquakes are generated when plates move relative to ...

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Miskien op ‘n ander manier dit se(raak ontslae van al die “of”s) ?The consequences of tsunamis are the death of thousands of people, destroying of homes, and the destruction of any man made equipment that gets in the way of the tsunami (Norman and Whitfield, 2006). No one can stop tsunamis happening. However, the effects of a tsunami can be reduced by making shorelines less vulnerable (Rothery, 2007).

Continental drifting is driven by the interaction between the oceans and the hot interior of Earth. Therefore, without oceans there would be no continents and no continental drifting and therefore, no new formation of oceans, no earthquakes or tsunamis. If this cycle did not happen, no new species would have evolved or no natural formation would occur. This shows us the importance of continental drifting and events occurring with it (McCarthy and Rubidge, 2005).