Case Study : Mariana TrenchAbout Mariana Trench :The Mariana Trench is the deepest point on Earth. The Mariana Trench is a crescent-shaped scar in the Earth’s crust that measures more than 1, 500 miles (2, 550kilometers) long and 43 miles (69 kilometers) wide on average. The distance betweenthe surface of the ocean and the trench’s deepest point – the Challenger Deep, whichlies about 200 miles (322 kilometers) southwest of the U.S. territory of Guam – isnearly 7 miles (11 kilometers). The pressure at the deepest part of Mariana Trench isover 8 tons per square inch. Location : The Mariana Trench is located in the western Pacific east of the Philippines and an average of approximately 124 miles (200 kilometers) east of the Mariana Islands.
Formation of Mariana Trench : 1) The oceanic crust, the Philippine Plate, is much heavier than the continental crust, the Eurasian Plate. 2) When these plates collide into each other, the Philippine Plate, which is much denser and heavier, sinks into the molten mantle, while the lighter, Eurasian Plate rides up over the top. 3) The forces driving the two plates together are really intense, so the subducted oceanic plate creates a trench where it drags the edge of the edge of the continental crust down as it descends underneath. Uses of Mariana Trench Mariana Trench is proposed as a site for nuclear waste disposal, in the hope that tectonic plate subduction occurring at the site might eventually push the nuclear waste deep into the Earth’s mantle. However, ocean dumping of nuclear waste is prohibited by international law. Furthermore, plate subduction zones are associated with very large mega thrust earthquakes, the effects of which are unpredictable and possibly adverse to the safety of long-term disposal. The Mariana Trench is often used as a North-South passage by submarines as it is part of a long system of trenches that circle the Pacific Ocean, connected with the Japan and Kuril Trenches. Trenches are becoming much more focused in the scientific community. Geologists now think these seismically active zones could play a central role in some earthquakes.