Plate Tectonics for Kids Tectonic plates explained

plate tectonics for kids in this video we're going to tell you about something called plate tectonics it sounds complicated and super sciencey but it's actually pretty simple once you know what it is but first stop what you're doing sit totally still can you feel the earth moving under your feet no you probably can't but guess what the earth is always moving beneath us it moves and shifts really really slowly of course as you know every once in while there's an earthquake somewhere and when that happens you actually can feel the earth moving if you've never been in an earthquake take minute to think about what that might feel like earthquakes occur when the earth beneath our feet moves or shifts lot really quickly and all of sudden but earthquakes like that the dangerous ones that we can feel are rare most of the time the land all over the world the land that we walk on is moving very slowly so slowly that nobody on land can feel it it moves between one and six inches per year and takes millions of years to notice it the slow movement is caused by plate tectonics so what are the plates and what are the tectonics the word tectonics is actually from the ancient greek word meaning pertaining to building so when we talk about plate tectonics we are literally talking about the way the earth was built as you might have already learned the earth is made up of several layers that go all the way down to its core the top layer of the earth that actually moves is called the lithosphere that layer consists of the earth's crust and part of the upper mantle and it moves in big pieces of land called tectonic plates they move because below them is layer called the asthenosphere the asthenosphere layer is basically liquid-like molten rock that moves around deep deep below the earth's surface and is all squishy like lava the rock is molten or in liquid form because the center of the earth itself is really really hot and radiates that heat upwards so the tectonic plates we just described are sitting on top of that molten rock in the asthenosphere that's what causes them to move and shift think of it as if the plates were giant ice cubes floating in huge glass of water these plates that sit closer to the surface are in fact huge some of them covering entire continents and they're made up of major plates and miter plates check out this map here you can see all the plates on earth as you can see there are seven major plates and 10 minor ones the first thing you may notice is that the major plates are kind of aligned with the continents that's not coincidence the continents on earth were actually formed due to the movement of these plates over millions and millions of years think of the earth as giant jigsaw puzzle made up of pieces that are basically parts of these major plates but these plates are just little bit bigger than your average jigsaw puzzle piece puzzle piece might be half an inch thick well these plates go down an amazing 62 miles into the earth if you had car that could drive down into the earth it would take an hour at highway speeds to get to the bottom of typical plate and there's not just one kind of plate either plates are divided into two kinds oceanic and continental oceanic plates are made from crust called sema that exist below the oceans sema gets its name because it's made from silicon and magnesium continental plates exist mainly below land and they're made up of silicon and aluminum and are therefore known as cl tectonic plates move mostly at the places where they meet at the boundary of two plates and there are different kinds of boundaries convergent divergent and transform let's explain imagine you have two big textbooks you're holding one and your friend is holding the other now let's pretend those textbooks are the plates under the earth if you and your friend push those textbooks up against each other really hard one book might be forced under the other that's convergent boundary so in the case of the plates under the earth when you have convergent boundary one plate slides under the other in process called subduction when that happens it forms mountains and volcanoes over long period of time earthquakes can also happen where these two land masses meet examples of convergent boundaries are mount everest and the mariana trench which is deep in the ocean now imagine those two textbooks again but instead of pushing them together you and your friend pull them away from each other that's what happens when you have divergent boundaries the area of land where this occurs is called rift and in those places you might find giant rift valleys examples include the east african rift valley the galapagos rise and the mid-atlantic ridge back to our textbooks this time imagine you and your friend put those textbooks against each other and rub them together up and down in lateral motion that's what transform boundary is like this type of boundary is more likely to create earthquakes examples of transformed boundaries include the san andreas fault in california and the alpine fault of new zealand all this shifting and movement is how all the different types of terrains on earth were formed and the continents themselves believe it or not over 250 million years ago all the different continents on earth were actually just one giant land mass called pangaea over millions and millions of years the continents of the earth formed due to this tectonic plate activity which moved the earth's crust around these days scientists are using gps technology to track the way the earth's crust is moving they hope to be able to use this technology to predict earthquakes and where they might occur all of this talk of movement might make you feel nervous about how steady the ground is beneath your feet but rest easy there is at least 62 miles of earth crust under your feet definitely enough to support you and your friends and even your dog thanks for following clarendon learning be sure to subscribe for more 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