Boy, I am jetlagged! I've just gotten off my flight in Kathmandu, the capital of Nepal. I am here to explore a different kind of plate boundary. Collision occurs when an oceanic plate completely subducts under a continental plate, and another continental plate smashes into it (the first continental plate). Since they are close to the same density, neither can go under the other like during subduction. Instead, they press together, fusing into one bigger plate and causing a mountain range to form along the fault line. You've probably heard of the Himalayan Mountains before, the tallest range in the world. They were formed by the subcontinent of India crashing into the continent of Eurasia. India is still pushing north towards China and Russia, moving at about 5 centimeters per year, which means the Himalayas are still slowly getting taller. There are no volcanoes in the Himalayas, but large earthquakes are fairly common. Usually there's at least 2 or 3 per year. In fact, there was a level 6.9 earthquake just 2 years ago in 2011, so I'd better be careful! Here are two pictures, the one on the top shows how collision works and the one on the bottom is a picture a man I met in town showed me from when he climbed Mt. Everest. Maybe someday I'll be able to do the same!
Great job explaining how a collision boundary works! It is easy to follow and well-written.
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