our last hazards video ended with us saying as you'll see in our next video the real action happens along the edges of the tectonic plates so now it's time to take a look at plate boundaries sometimes also called plate margins which are all of the parts of the world where one tectonic plate is next to [Music] another constructive sometimes also called divergent plate boundaries exist in the parts of the world where magma is rising up in the mantle below this rising magma cools off and spreads out [Music] some of it solidifies and creates new crust which begins to slowly move apart as two separate tectonic plates these types of boundary mostly appear at the bottom of the sea there are some places like iceland where you can actually see evidence on land of the tectonic plate splitting apart so what type of hazards do we find here and why let's start with volcanoes some of the magma along with gases like carbon dioxide can melt through the crust and get released out of the surface which is basically what a volcanic eruption is so yeah we get volcanoes often with lots of lava earthquakes do happen at constructive boundaries but they aren't usually that powerful you see an earthquake happens when tectonic plates get stuck or grind against each other it just doesn't happen very much at this kind of boundary because the plates are mostly moving apart [Music] destructive sometimes also called convergent boundaries are areas where tectonic plates are being carried towards each other but there are actually two different types if an oceanic plate is moving towards a continental plate the oceanic plate is forced underneath because it is denser in a process we call subduction as the oceanic plate sinks into the mantle water and things like dead plankton on the sea floor are dragged down with it these are turned into water vapour and carbon dioxide which bubble upwards and melt through the continental crust above you get trapped in the rock pressure begins to build up much like it does when you shake a bottle of fizzy drink and eventually the pressure in the crust becomes too grey and the gas and lava violently explode out of the rock in a volcanic eruption extremely powerful earthquakes can also happen at these destructive boundaries the oceanic crust doesn't simply slide gently past a continental pipe these huge rough slabs of rock are constantly grinding against and getting stuck on each other and when they do get stuck the continental plate starts getting dragged down with the oceanic plate it builds up a huge amount of energy as this happens and when the plates finally become unstuck the plate violently jumps upwards releasing all of the stored energy and causing intense shaking in the ground we know this as an earthquake the second type of destructive plate boundary is known as a collision boundary the big difference here is that both of the tectonic plates are continental so they have roughly the same density they crash head-on and crumple upwards creating what we call old mountains you can see this is happening between tectonic plates like the indian and eurasian plates where the force of the two plates colliding has created the mighty himalayas mountain range as you can imagine the process of forming a mountain range isn't a smooth one the plates grind and crack and buckle upwards over millions of years and at times they get locked together and get stuck on each other eventually the plates build up enough energy to become unstuck the plates jolt back into movement and an earthquake is created oh and don't confuse these mountains of volcanoes there's no magma rising up from underneath them so you don't get any volcanic eruptions at collision boundaries conservative boundaries sometimes also called transform boundaries are so named because the tectonic plates are not being constructed or destroyed here so it is conserved which means to be kept the way it is these conservative boundaries happen at places where two tectonic plates are sliding past each other either in opposite directions or in the same direction at different speeds the edges of the plate get stuck on each other as they grind past and you probably know the raspberry it builds up energy and after a while they jump back into moving again and the energy gets released causing the ground to shake earthquake following the same rules as before there is no magma rising up underneath the crust at a boundary like this so you guessed it no volcanoes and that will be all for this video as always thank you very much for tuning in and if you enjoy our content please consider liking and subscribing and also hit the little bell ding if you wish to be notified every time we upload a new video as always you've been listening to the mountain man and watching the work of michael deluxe remember keep it simple