Mod+5.6+-+Ben+S

Dynamic Earth


 * Divergent Boundaries**
 * formed when magma rises and pushes plates apart
 * this renews the ocean floor and widens giant basins
 * the mid-atlantic ridge connects all oceans
 * the mid-atlantic ridge is a chain of mountains formed by a divergent boundary
 * created the Great River Valley in Africa when the magma rose to the surface and pushed he plates apart[[image:divergentboundary1.jpg]]


 * Convergent Boundarie****s**
 * formed when a plate collides with another plate or dives under another plate
 * a Subduction Boundary is a sub boundary of a Convergent Boundary
 * another sub boundary is a Collision Boundary
 * a Collision Boundary is formed when 2 continent plates collide and get "welded" into a single, larger continent
 * a Subduction Boundary is the space between an oceanic plate that dove under another plate
 * an example of a Convergent Boundary are the Himalayas. the India plate and the Asia plate collided and pushed these very large mountains through the surface
 * it can also form deep sea-trenches like the Mariana Trench in the North Pacific
 * this boundary also has some earthquake activity


 * Transform Boundaries**


 * formed when two plates grind against each other and slide by
 * an example is in California where the Pacific Plate and the North American Plate are sliding past each other along the San Andreas Fault
 * the two plates move 5 centimeters a year
 * this type of boundary often causes earthquakes
 * these boundaries do not produce spectacular mountains and volcanoes


 * Citations**
 * "Moving and Shaking." //National Geographic//. 1996. Web. 11 Nov. 2009. .