 This is the third and final video on convergent plate boundaries in the series of videos on plate tectonics. This is this particular video is talking about continent-continent collision, a very interesting type of convergent plate boundary where two continents collide into each other. What do you think happens in this scenario? The best analogy picture I have is of two cars colliding. Notice the hoods popping up, neither car going below the other in this case and these popped up hoods represent very large mountains in this case. Some of the features of this type of convergent boundary are medium to large earthquakes, such as the recent Nepalese and Pakistani earthquakes in the area. The earthquake zones of these particular types of boundaries are more broad and spread out and not quite as focused as the ones you see with the ocean-ocean-ocean-continent convergent boundaries. Note that continental crust can't really be subducted. So instead of subducting, it goes up and piles on top of itself when two plates collide that are continental crust. If you don't have subduction, you're not taking the water down into the mantle area, meaning you're not creating a volcanic arc. So in this kind of collision, you do not have volcanoes, just earthquakes. Where is this happening? A great example is the Tibetan Plateau in the Himalayan Mountains, where the Indian plate has collided with the Eurasian plate, creating this very wide area of deformation in some of the tallest mountains in the world, or the tallest mountains in the world. Here's kind of a side view of that collision and note how the Indian plate rams into the Eurasian plate and kind of stacks pieces of itself on top of themselves. And you create all of these, what's known as reverse faults, where chunks of material are being stacked on top of each other. In both cases, almost like a snow shovel stacking snow on top of itself as it moves through the snow. This collision, here's a picture of the Indian continent 71 million years ago and slowly moves up, colliding into the Eurasian plate 10 million years ago and creating these massive mountains in a relatively short amount of geologic time. Here's a beautiful aerial photo showing the area of deformation caused by this collision outlined in the yellow lines here. Notice all of the wrinkles and basins and linear type things looking very much like piled up snow in front of a snow shovel. All of this is wrinkled and folded in response to these two continents colliding. Very much like what you see in the Appalachian Mountains, where you have these beautiful folds and wrinkles from a similar collision between two continents when Pangea formed. So the Appalachian Mountains are the remnant of a great mountain chain caused by conic-conic collision. Where is this about to happen? In the Mediterranean Sea this area is beginning to close up and you're starting to get the beginning of what will likely be a conic-conic collision. This is all part of a cycle of opening and closing ocean basins known as the Wilson cycle. We'll get into that in more detail in future lectures, but just note that geologists have noticed that the breaking up of continents creating a small, divergent spreading zone or rift zone, which in turn creates a much larger oceanic basin and that ocean basin eventually closes back up. This whole cycle is known as the Wilson cycle. We also have these cycles of supercontinents where you have everything breaking apart and then coming back together, these big mountain forming events where eventually you get a supercontinent like Rodinia and then you open up these basins again and bring everything back together again and you get a supercontinent, which the most recent one being Pangea. For the next video we'll talk about divergent boundaries, so please do watch that if you get the opportunity and thank you.