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 * Dynamic Earth**

There are three types of boundaries. The three types are convergent, divergent, and transform boundaries. Divergent boundaries are caused by magma under the crust mainly in the ocean rises to the surface and pushes apart two plates. Mountains and volcanoes rise along the seam of where two or more tectonic plates spread apart. A single mid-Atlantic ridge system connects the worlds oceans making the ridge the longest in the world. On land, The Great Rift Valley in Africa formed where plates had been tugged apart. In a million years scientists believe if the plates continue to diverge Eastern Africa will split apart from the rest of the continent and form a new landmass. When plates serving as landmasses collide, the crust crumples and buckles into mountain ranges. India and Asia crashed about fifty-five million years ago and slowly gave rise to The Himilayas. Convergent boundaries can be classified into two groups. These groups are Subduction boundaries and Collision boundaries. Subduction boundaries are when a oceanic plate plunges beneath another. An important feature of these boundaries are that deep-sea trenches form along these boundaries. Collision boundaries are the boundaries that form when two continents collide and welded into a single layer, this causes the crust to push upward creating mountain ranges. Some examples of convergent boundaries are: Mount Shasta in california, and The Indonesian island Krakatua. When two plates grind past each other on what are called strike-slip faults these are called Transform boundaries. When plates get caught the halting motion causes earthquakes. Such an earthquake occured in 1906. The earthquake caused tons of damage and tragedy throughout San Francisco. Examples of Transform boundariesthe San Andreas fault in California and the North Anatolian Fault in Turkey. ****Citations-**
 * Divergent Boundaries-**
 * Convergent Boundaries-**
 * Transform Boundaries-
 * "The Dynamic Earth." //National Geographic The Dynamic Earth//. National Geographic, 2009. Web. 9 Nov. 2009. .
 * Spaulding, Nancy E., and Samuel N. Namowitz. //Earth Science//. Evanston, IL: McDougal Littel, 2005. Print.
 * "Plate Tectonics." //Dynamic Earth//. 2009. Web. 9 Nov. 2009. .