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Convergent Boundary


A convergent boundary forms when plates collide and the crust crumbles into mountain ranges. Indian and Asia collided about 55 million years ago, slowly this turned into the Himalaya, the highest mountain system on earth. When two convergences collide one usually goes under the other one forming a trench. One big trench is the Mariana Trench in the north pole was formed from two convergences. There are three ways that convergent boundaries can be made. An ocean plate can hit an ocean plate forming a trench, an ocean plate can hit a continental plate usually forming a trench, and two continental plates can hit making a mountain range.

Divergent Boundary


A divergent boundary forms when magma rises from the earth and pushes two plates apart. The sea water cools the hot molten rock coming out of the diverging plates and the molten rock turns into new oceanic lithosphere. The process of the cooling of molten rock builds a chain of volcanoes called mid-ocean ridge or spreading ridge. One divergent boundary plate boundary os splitting the Arabian Peninsula and Africa. This is forming the Red Sea.

Transform Boundary
San Andreas Fault

A transform boundary forms when two plates grind past each other along strike-slip faults. The San Andreas Fault in California is made from the Pacific Plate(on the west) and the North American Plate(on the east). When two plates move past each other, like the Pacific and the North American Plate, they form earthquakes around the transform boundary. Transform boundaries do not produce mountains or oceans but they trigger large earthquakes, such as the one that destroyed San Francisco in 1906. >
 * "Understanding Plate Motions." //USGS//. N.p., 5 May 1999. Web. 5 Nov. 2009. [].
 * "Plate Tectonics." //National Gegoraphic//. n.d. Web. 6 Nov. 2009. [].
 * "Plate Tectonics." //Nettrekker//. N.p., n.d. Web. 6 Nov. 2009. .
 *  "Geology." //Geology.com//. N.p., n.d. Web. 6 Nov. 2009. .

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