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​Convergent Boundaries
 * Convergent Boundaries are plates serving landmasses collide, the crust crumples and buckles into mountain ranges.
 * India and Asia crashed 55 million years ago, slowly giving rise to the Himalayas (the highest mountain system on Earth)
 * as the mash-up continues, the mountains get higher
 * Mount Everest (the highest point on Earth) may be a tiny bit taller than it is today
 * plates may occur where a plate of the ocean dives (subduction) under a land mass
 * the over lying plate lifts up and forms mountain ranges
 * the dividing plate melts and is often spewed out in volcanic eruptions such as those that formed some of the mountains in the Andes of South America
 * at ocean-ocean convergences, one plate usually divides beneath the other forming deep trenches like Mariana Trench in the North Pacific Ocean
 * these types of collisions can lead to underwater volcanoes that eventually build up into island arcs like Japan

-Himalayas Divergent Boundaries
 * the most common typer of mountain formation (folded)
 * consists of several parallel mountain ranges
 * 30 to 50 million years in different stages the Indian plate collided with the Eurasian Continental Plate to form the Himalayas
 * averaging 200-250 miles in width, rises sharply from the Indo-Gangetic Plain and seperates northern India from the plateau of Tibet
 * in oceans, magma from deep in the Earth's mantle rises toward the surface and pushes apart to move plates (Mountains and Volcanoes rise along the seem)
 * process renews the ocean floor and wident the giant basins
 * single mid-ocean ridge the laongest mountain range in the world
 * on land, giant troughs such as the Great Rift Valley in Africa form where plates are tugged apart
 * if the plates continue to diverge, millions of years from now, Eastern Africa will split from the continent to form a new landmass
 * mid-ocean range would then mark the boundary between the plates.

Transform Boundaries
 * where two plates grin againt each other along what are called strike-slip faults
 * San Andreas Fault in California is an example
 * these boundaries dont produce spectacular features like mountains or oceans, but halting motion often tiggers large earthquakes

-San Andreas Fault Earthquakes Volcanoes Citations "Earthquakes." //Earthquakes The Rolling Earth//. Web. 12 Nov. 2009. . "Himalayan Mountains." //Virtualology.com//. Evisum Inc., Web. 12 Nov. 2009. . "Plate Tectonics." //National Geographic//. National Geographic Society, Web. 12 Nov. 2009. . "San Andreas Fault." //USGS//. Web. 12 Nov. 2009. . "Volcanoes." //Volcano World//. Web. 17 Nov. 2009. .
 * the San Andreas Fault system is over 800 miles in length
 * it extends to al least 10 miles within the Earth
 * an earthquake is a sudden, rapid shaking of the Earth caused by the release of evergy in stored rocks
 * the energy can be built up and stored for manny years an then released in seconds or minutes
 * mandy earthquakes are so small that they cannot be felt by humans but some have caused gread destruction and have killed hundreds of thousands of people
 * there are two major regions of earthquake activity, one is the circum-Pacific belt which encircles the Pacific Ocean and the other is the Alpide belt which slices through Europe and Asia
 * the curcum-Pacific belt includes the west coasts of North America and South America, Japan, and the Phillipines
 * over one million earthquakes may occur each year
 * most earthquakes last only seconds, but some large quakes may last minutes
 * about 90% of earthquakes are produced at plate boundaries where two plates are colliding, spreading apart, or sliding past each other
 * when these plates move suddenly they release an incredible amount of energy that is changed into wave movement
 * earthquake waves resemble sound and water waves in the manor in which they move
 * it's these waves that roll through the Earth's crust causing buildings to collapse,bridges snap,mountains to rise, the ground to fall, and in some cases the ground to open up into huge cracks
 * volcanic activity is the most powerful force in nature
 * volcanoes have killed thousands of people and have created some of the most frightening events in human history
 * volcanoes have been the bases for myths and legends the world over
 * volcanoes are also reponsible for much of the land se live on, 90% of all continents and ocean basins are the broduct of volcanoism
 * the air we bearthe and the water we drink have been produced by millions of years eruptions of steam and other gases