To believe in plate tectonics – which, by the way, is true beyond any doubt – you need to\u00a0picture this:\u00a0\u00a0Earth’s surface\u00a0\u00a0consists of large islands of solid rock floating on a sea of magma.\u00a0\u00a0There are about 9 large plates, plus some smaller ones.\u00a0 Examples are the Indian Plate, the North American Plate, the South American Plate, the Eurasian Plate, the African Plate and\u00a0the Pacific Plate.<\/p>\n
The plates more or less cover the sea of magma beneath them.\u00a0 At the same time,\u00a0because the plates float on the\u00a0magma, they move around like toy boats in a bath tub.\u00a0 When they move apart, you have what’s called a divergent boundary.\u00a0 When they crash together, you have a convergent boundary.\u00a0 When they rub alongside each other, going in parallel but opposite directions (perhaps like people passing each other in a crowded hallway), you have a transform boundary.\u00a0 Essentially, the term fault can be substituted for boundary.<\/p>\n
At a divergent boundary, a crack\u00a0eventually forms\u00a0between the plates, then magma\u00a0leaks up between them,\u00a0so you get\u00a0volcanoes.\u00a0 The volcanoes can eventually form high\u00a0ridges as they continue to erupt.\u00a0 Divergent boundaries are more common under the sea than on land.<\/p>\n
At a convergent boundary, there are two possibilities.\u00a0 One is a\u00a0head-on collision, in which case\u00a0the plates buckle as they crash (like in a car crash).\u00a0\u00a0The plates deform upward, resulting in mountains.\u00a0 The Himalayas are such a mountain range, caused by the collision of the Indian Plate and the Eurasian Plate.<\/p>\n
The second possible outcome at a convergent boundary is subduction, which is where one plate rides over top and the other slides below.\u00a0 If one plate is a continental one and the other is a sea plate, the sea plate slides under and the continental one rides up, forming a mountain chain.\u00a0 The Andes Mountains\u00a0exemplify such a situation:\u00a0 there, the Nazca Plate is sliding under the South American Plate.<\/p>\n
Although each type of boundary\u00a0hosts earthquakes, a transform boundary results, especially,\u00a0in earthquakes.\u00a0 As the plates try to shove past each other, they get stuck.\u00a0 The pressure builds, then they break loose, resulting in sudden movement – and an earthquake.\u00a0 The famous San Andreas Fault at San Francisco is a transform boundary: the Pacific Plate is running NNW, while the North American Plate is running SSE, along it.<\/p>\n
Hope this gets you started :)<\/p>\n