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Convergent Boundary:

A convergent boundary is when two plates are moving toward each other. The plates collide and one plate is forced under the other one to form mountain ranges. One example of a convergent boundary is where the Himalayas were formed from India and Asia colliding between 40 and 50 million years ago. Since their landmasses were about the same, neither one could be forced down. The only other place to go was up which formed the rocking Himalayas. Another example is the Andes Mountains. They were formed between oceanic and continental plates. To form the Andes, the Nazca plate subducted under the South American plate.

Divergent Boundary:

A divergent boundary is when plates move away from each other. When this process in oceanic, new magma rises and renews the ocean floor. This also widens the ocean basin. The Mid-Atlantic Ridge is an example of an oceanic divergent boundary. The Mid-Atlantic Ridge is a submarine mountain range. The deepest part of it this Challenger deep. The East Africa Rift Valley is another example. The Rift Valley was formed about 65 million years ago. On the northern reach of the valley, it separates Africa from that part of Asia. If it continues to move it will eventually break off of Africa.

Transform Boundary:

A transform boundary is when to plates slide past each other. Transform boundaries are sometimes called conservative boundaries because nothing is created or destroyed. Instead large earthquakes occur by the boundaries. The San Andreas fault is one example of this boundary. This fault connects a divergent boundary in the gulf of California to the Cascadian subduction zone. This fault might eventually cut California in two. My last example is the Alpine fault in New Zealand. Sliding along this fault was first pointed out by H.W. Wellman in 1952.

Bilbiography:

"divergent plate boundaries." //goelogy.com//. N.p., 2005. Web. 29 Nov. 2009. . "The himalayas." //USGS//. N.p., 1999. Web. 29 Nov. 2009. . "plate techtonics." //National geographic//. N.p., 1996-2009. Web. 29 Nov. 2009. .