Rocks Essay

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Rocks Terrestrial geology is no longer unknown to mankind. Minerals, mountains and rocks have been listed and identified and their different training that all result from the same phenomenon of movement in the Earth's mantle called CONVECTION . This movement results from the rise of magma into the lithosphere that then cools and becomes heavier and falls in after he returned temperature and back again. This cyclical movement has effects in the Earth's Procrustes , because it causes the movement of tectonic plates , such as a treadmill. Tectonic movements are responsible for the formation of terrestrial landscapes, oceans and continents training as we know it today, but also rocks . In the remainder of this attempt there is a brief presentation of 5 differents rocks that form the Irish geological structure with its description and training from the movement of tectonic plates : The Limestones This sedimentary rock is named Limlestones when a fraction of carbonate (Calcite formed from the shells or dead marine organisms) exceeds the non carbonates constituents. They are formed of carbonate of lime with various impurities, almost all in great mesure of organic origine. They are polygenic, some are fragmental or detrital and are mechanically transported and deposited others are chemical or biochemical precipitates and are formed in place. Approximately 40% of ireland’s lands are undelain by limestone. The fossils and others organics like shells can be founded on limestones, that proves this regions was before under water and a slow drought of that oceans and the colision of the plates put that rocks on superficies. The Basalt The basalt is an extrusive ignous rock with two pricipal visual characteristics : a dark color and fine crystals (Fine-grained Rock), this last characteristic come from the slow cooling of magma in contact with the

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