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At divergent boundaries in the oceans, magma from deep in the Earth's rises towards the the surface and pushes apart two or more plates. Mountains and volcanoes form along the seam. The process renews the ocean floor and widens the giant basins. A single mid-ocean ridge system connects the world's oceans, making the ridge the longest mountain range in the world. Divergent boundaries are locations where plates are moving away from one another. This occurs above rising convection currents. The rising current pushes up on the bottom of the lithosphere, lifting it and flowing laterally beneath it,this lateral flow causes the plate material above to be dragged along in the direction of the flow. The African plate and the Arabian plate spread apart to form the Red Sea. The Nazca plate is also a divergent plate boundaries.
 * Convergent plate boundaries** are when a **continental and an oceanic plate** make contact and **the thinner more dense oceanic plate is over ridden by the thicker less dense continental plate**. **This is where plates serving as land masses collide**, **the crust crumples** and **buckles into mountain ranges. India** and **Asia crashed about 55 million years ago**, **slowly giving rise to the Himalaya**s, the **highest mountain system on Earth**. These convergent boundaries also occur where a plate of the ocean dives, in a process called **"Subduction"**, under a land mass. As the overlying plate lifts up, also forming mountain ranges. The diving plate melts and is often spewed out in volcanic ash. At ocean-ocean convergencies, one plate usually dives underneath the other forming deep oceanic trenches like the "Mariana Trench", the deepest point on Earth. These types of collisions can also cause underwater volcanoes that eventually become island arcs, like Japan. The Philippine plate is an excellent example of a convergent boundary.



In this example picture the lithosphere diverges from one big sheet into two smaller but still big sheets of lithosphere. The asthenosphere is set below the lithosphere is holding the magma. As the lithosphere spreads apart the magma below in the asthenosphere pushes up threw and out forming a new layer up top on the lithosphere. This spreads the land East to West making more land, but where the lithosphere splits apart and the magma pushes threw a ridge is formed because of the magma bubbling up.

The Mid-Atlantic Ridge is a classic example of this type of plate boundary. The ridge is a high area compared to the surrounding sea floor because of the lift from the convection current below. A transform boundary is where two of these particular plates grind past each other in what are called strike-slip faults. Transform Boundaries do not create mountains or oceans but the halting motion often creates large earthquakes. A key excellent example of a transform plate boundary is the North American plate.

This is a picture of the San Andreas fault in California. This is a key example of a transform boundary. The San Andreas fault slice California in two form Cape Mendocino to the Mexican border. Despite San Francisco's legendary earthquake the San Andreas fault does not go through the city. The San Andreas fault was caused by the North American plate and the Juan De Fuca plate pushed against each other.

"plate tectonics." //natoinal geographic//. nd. Web. 16 Nov. 2009. "plate boundaries." //geology//. nd. Web. 16 Nov. 2009. "himalaya." //himalayas//. N.P, nd. Web. 17 Nov. 2009. "San Andreas fault." //San Andreas Fault//. Web. 17 Nov. 2009.

