Vulcancity Essay

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VULCANICITY AND THE FEATURES THEY PRODUCE The nature of landform in a region is shaped by two processes, which are at the work on the earth's crust. These are called the external forces and the internal forces. The external forces are those, which operate on the surface of the crust by external agents of weathering and denudation. These include the work of river, glaciers, winds and waves. The Internal forces operate in the earth's interior layers. Forces build up gradually and suddenly the crust may be subjected to earth movements or volcanic activity or mountain building. Their effect is observed suddenly in the form of earthquakes or volcanic eruption. The earth’s crust is altered by the constant forces resulting from plate movement. Tectonic (generated from within the earth) forces are of two types, either diastrophic or volcanic. Diastrophism is the great pressures acting on the plates that deform them by folding twisting, warping breaking, or compressing rock. Volcanism is the force that transports heated material to or toward the surface of the earth. Therefore, Vulcanicity consist of all the processes through which solid, liquid and gaseous materials are injected into the earth’s crust, or thrown out onto the surface of the earth. Thus, it is through vulcanicity that a volcano is formed. A volcano is actually an opening or a fissure in the earth’s crust through which lava or molten rocks, ash and toxic gases present below the surface are discharged by a sudden violent eruption. Sometimes it can be a mountain like structure with a bowl shaped depression at the top through which these substances are expelled. Volcanoes through vulcanicity can be broadly discussed under the following categories; types of volcanoes, places of vulcanicity, landforms and features of vulcanicity, effects of vulcanicity and benefits from volcanoes. Initially, there are three
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