Explain the differences between Basaltic, Rhyolitic and Andesitic volcanic eruptions.docx uploaded successfully
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Explain the differences between Basaltic, Rhyolitic and Andesitic volcanic eruptions with reference to processes, which lead to the eruptions, the type of volcano produced and the reasons for the differences between the material erupted by these volcanoes.
Volcanic eruptions are caused by a red-hot liquid rock, called magma inside the earth's core. Volcanoes erupt when magma rises to the surface of the earth, which causes bubbles of gas to appear in it. This gas can cause pressure to build up in the mountain, and it eventually explodes. When the magma bursts out of the earth, it is called lava. The type of magma in the earth can create different volcanoes. If the magma is quite thin, the gas can escape easily and there will not be an…show more content… Fast occurs in the Pacific and slow in the Atlantic. Furthermore, there are plate boundaries Beneath Continents that sometimes-divergent currents occur beneath continents in which the continent breaks apart, producing a rift valley e.g. the Great African Rift Valley in East Africa. In a rift valley you find lakes and volcanic activity e.g. Mount Kilimanjaro. In time the rift valley will develop into an ocean of its own.
Lastly, there are Destructive Plate Margins and conservative plate margins. Destructive Plate Margins are the places where the Earth’s crust is being destroyed at the same rate as they are being formed at the constructive plate margins. Oceanic Convergence is where oceanic and continental plates meet. As oceanic plates are denser they go down toward the Mantel; this is subduction. Sediments that have accumulated at the bottom of the ocean form land mass as they rise as they melt due to the magma, through the continental crust and then re appear as the continent. Also, there is oceanic convergence. This is where two oceanic plates meet; one is forced under the other. Oceanic trenches are formed and island arcs; (Hawaii). Lastly, there are continental convergence where two continent plates meet and sediment is forced up to form mountains. And, Conservative Margins are where two plates slide over each other and there is neither creation nor destruction takes place. There is no subduction or volcanic activity. However, the plates move