Divergent Boundaries Speech
The diverging plates below us are moving everyday; reshaping our world, slowly, but surely. These divergent boundaries are being studied around the world and they teach us about our evolved world, and its continuing evolution today. There are two types of divergent boundaries, the oceanic and the continental. These occur where their names have defined, within the oceanic crust and the continental crust. Both begin at the movement of the convection currents, which push plates up and away from one another. The continental divergence starts above ground in its early stage, and gradually forms a rift that fills with water as the valley expands, and eventually completely rifts as the valley reaches below sea level. An example of this divergent zone in its early stage is the East African plate boundary, which is expanding to separate the African plate as well as the continent, into two. An example of this divergent zone in its complete rifting stage is the Red sea, which has fully developed; the valley below sea level. This type divergent boundary had caused the separation of South America and Africa, which separated the continents, and turned into an oceanic divergence after the rift valley had sunken below sea level, and is still growing today. Oceanic divergences develop quite differently, as the convection currents lift the ends of the plates, forming a ridge, and their opening fills with magma and cools; this then repeats itself. The most famous oceanic divergent boundary is the mid Atlantic ridge, the 10,000 mile unseen mountain range that dominates as the longest of them all, making the Atlantic Ocean continually bigger, since the Triassic period. This boundary has proven the existence of sea floor spreading, as Harry Hess was studying the ocean floor and found the crust’s ridges having newer rock at the middle of the ridge. Scientists are currently studying this ridge in Iceland, where the boundary runs right in the middle of the...
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