Thursday, March 13, 2008

Plate Tectonics

The plate tectonics are always shaping the earth’s crust and its surface.
There are a few handfuls of major plates and dozens of smaller, or minor, plates. Six of the majors are named for the continents embedded within them, such as the North American, African, and Antarctic plates. Though smaller in size, the minors are no less important when it comes to shaping the Earth. The tiny Juan de Fuca plate is largely responsible for the volcanoes that dot the Pacific Northwest of the United States.
The plates make up the earths uppermost mart of it called the lithosphere. Most of the activity that occurs happens where the plates meet or divide.
The places where the plates meet or divide are called boundaries. There are three main different kinds of boundaries. These boundaries are called convergent, divergent, and transform boundaries. Convergent boundaries are the types of boundaries were the plates are colliding with one another or when one dives under the other. Usually this occurs when there is an earthquake or when an oceanic plate slides under a continental plate. A good example of this is the Appalachian Mountains, which were made from colliding plates. Divergent is the name of the second one in which magma rises and pushes the two plates apart. When the plates separate, the magma that separated it fills the voids in the earth’s crust therefore changing the surface of the earth. This usually happens under the ocean when one plate separates and the ocean cools the magma. The last of the tree boundaries is called a transform boundary, which is where the two different plates slide past each other in a scissors form. There are a lot of places where this happens you can even see in on the walls on the road when you are driving.
This is how plate tectonics shape the earth with the different types of boundaries.



Anonymous said...

very nice, you explained the boundries quite nicely making it relativly easy for the reader to understand. Thank you for such useful information...

Anonymous said...

very well written. This info is very useful when trying to see how earth formed

Anonymous said...

very good writing style. You did well giving useful information (RS2)