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By: Meredith Staats When land masses collide, they form mountains. As these plates crush closer, mountains get taller. These plates also crush under the oceans, forming underwater mountain ranges.The Himalaya Mountains were formed when Indian Plate and Eurasian Continental Plane crushed closer together 55 million years ago. The Himalayas are still growing, Mt. Everest being its tallest point. When a plate forms under another plate, it forms trenches. These collisions can eventually form underwater volcanoes to form into islands, like Hawaii or Japan.
 * Convergent boundaries** are where plates move into one another.



At **divergent boundries** in the oceans, magma from deep in the Earth's mantle rises toward the surface and pushes apart two or more plates. This will form mountains and volcanoes along the seam. This process changes the ocean floor and widens great basins. Divergent boundries cover oceanic rift zones and contintal rift zones. They form from tension and uplift. An example of a divergent boundry is a giant trough in the Great River Valley of Africa where the plates are pulled and tugged apart. At this rate, in millions of years, the entire eastern part of Africa will spilt from the rest of the continent.




 * Transform Boundary-** where two plates grind past each other along what are called strike-slip faults. These don't form mountains or volcanoes, but cause massive earthquakes, such as the 1906 earthquake that attacked San Fransisco. An example of a transform boundary is the San Andreas Fault in California.



Bibliography:

Evisum Inc.,. "Himalaya Mountains." //Virtualology.com//. Evisum Inc,, 2000. Web. 16 Nov. 2009. .

National Geographic Society,. "Plate Tectonics." //Science and Space//. National Geographic, 1996-2009. Web. 13 Nov. 2009. .

Tectonic Globe,. "The Story of Plate Tectonics." //Plate Tectonics//. Tectonic Globe, 18 Nov. 2009. Web. 18 Nov. 2009. .