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Dynamic Earth

There are many plates that cover the earths surface. Different plate boundaries occur when plates collide or touch. There are three main types of plate boundaries. There is convergent boundaries, divergent boundaries, and transform boundaries

__Convergent boundaries__ are plates that move into one another. These type of boundaries create mountains and trenches. When these plates create mountains, two plates collide, the both buckle and rise up, creating mountains. When a trench is created one plate goes under the other, creating a trench.

The __Himalaya Mountains__ were created by convergent boundaries. About 30 to 50 years ago, the Indian plate and the Eurasion plate collided, createing the Himalaya Mountains.

Another example of a convergent boundary is the Aleutan Islands. The Aleutan Islands is made up of volcanic islands. They line up along the boundary between the north american plate and the pacific plate.



The Caribbean Volcanic ark is another convergent boundary. The Caribbean plate came in contact with the south american plate, creating the Caribbean Volcanic ark.



Divergent Boundaries are plates that move apart. This process renews the ocean floor and widens the great basins. The crust gets wider where there is a divergent boundary. It also creates shallow earthquakes. Divergent Boundaries create a split in the crust, which allows magma to rise.



One example of a Divergent Boundary is the Mid-Atlantic Ridge. Volcanic activity and liner fracturing within the rift valley of the mid-atlantic ridge. Fissure marks the position of the Mid-Atlantic ridge. Lateral offsets in the ridge are caused by divergent faults. Another example is in East Africa and is the Linear Lakes. Linear lakes within the rift valley of a developing divergent plate boundary in East africa.



A third example is the Red Sea. The narrow sea formed where the african and the arabian plate diverged. The plates moved apart, which created the red sea.



Transform Boundaries is a third type of boundary. Transform boundaries slide past each other. This creates earthquakes, because of the friction between the two plates that are sliding past each other. Unlike convergent boundaries, that make mountains and trenches, transform boundaries just cause earthquakes.

One common example of a transform boundary is the San Andreas fault. The San Andreas fault is located in California. The Pacific Plate and the North American plate, slide past each other, which create a lot of earthquakes in California.



Another example is the Alpine Fault. This fault is made up of the Australian plate and the Pacific plate. These two plates slide past each other, therefore they are a Transform Boundary.



Transform Faults are formed in the fracture zone between the pacific and north americain plates. This is another type of transform boundary. In the picture below you can see how there is two plates. It looks like a split in the earth.



Stein, Seth. "Plate Tectonics." //National Geographic//. National Geographic Society, 2009. Web. 5 Nov. 2009. .

"Plate Tectonics Map- Plate Boundary Map." //Geology.com//. Geology.com, 2009. Web. 6 Nov. 2009. .