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Dynamic Earth

Divergent boundaries- Divergent boundaries are when magma rises, then pushes two plates apart from each other. This is most common along the ocean floor. When this does happen, new crust is formed as the plates move away from each other. When divergent boundaries happen in the ocean they are caused by the sea floor moving. Divergent boundaries are also called spreading centers and they involve two lithospheric plates. Some examples of divergent boundaries are the East Pacific Rise which is caused by the Pacific Plate and the Australian Plate. The Mid-Atlantic Ridge which is submerged and runs about 25,000 miles, is caused by South American Plate and the African Plate.

Convergent boundaries- A convergent boundary is caused when a plate runs into or goes under another plate. When this happens, the crust crumples then buckles forming mountain range, such as the Himalaya mountains which are the highest mountain system on earth. As the crust continues to buckle the mountains get higher. In a convergent boundary the crust gets destroyed and it could also cause earthquakes. One example of a convergent boundary is the islands of Indonesia caused by the Indian Plate and the Philippines Plate.

Transform boundaries- Transform boundaries are caused when two plates grind against each other. This causes no damage to the crust though, it causes fracture zones. There are many examples for transform boundaries. A couple of these are the North Anatolian Fault in Turkey, and the Andrea's Fault in California. The San Andrea's fault is caused by the North American Plate and Pacific Plate. Citations

"The Dynamic Earth." //National Geographic//. National Geographic Society, 1996. Web. 5 Nov. 2009. .

"Himalaya Mountains." //n.p.//. Evisum Inc., 2000. Web. 6 Nov. 2009. .

"What Is the Mid-Atlantic Range?." Conjection Corporation, 2003. Web. 7 Nov. 2009. .