Tectonics in Middle America
The idea of the continental drift was first though up by a man named Albert Wegener in 1912 but the idea of moving continents was not taking seriously until the 1960. This study is called plate tectonics, and it helps explain the continental drift, the spreading of the seafloor, why volcanoes erupt and how mountains are formed. The mountain range that runs from the northern tip of Alaska to the southern tip of South America were formed by the buckling of crustal rocks that crash into the edge of North and South America. The land folds under the pressure of the colliding plates and pushes up sedimentary rock up to create mountains. It takes three different activities together to create mountains. These activities, the Oceanic Plates, the Continental Plates colliding, volcanic activity, and earthquakes are the reason why mountains are formed. Using the study of plate tectonics, the earth shell is split into nine large plates and a dozen smaller plates. Oceanic plates make up much of ocean floor, and the continents are embedded in continental plates. Circulation of the Mantle rock that is constantly being driven up to the surface by the high temperatures below and then sinking below again when it cools cause the tectonic plates to move. The oceanic plates around Middle and South America are the Cocos Plate and the Nazca Plate. There are three continental plates, the North American Plate, the Caribbean Plate and the South American Plate. The process that creates mountains in South America is the Nazca plate being pushed under the continental part of the South American Plate. When these plates collide, the South American plate splits into two layers. The lower layer is made up of dense mantle rock and the upper layer is made of a lighter crustal rock which is to buoyant to sink. When the mantle layer sinks, the crustal layer peels off, crumpling up against the South American Plate to form massive mountain ranges, such as the Andes. The Pacific coast along