[Script Info]
Title: 
[Events]
Format: Layer, Start, End, Style, Name, MarginL, MarginR, MarginV, Effect, Text
Dialogue: 0,0:00:00.21,0:00:03.03,Default,,0000,0000,0000,,Our last hazards video ended with us saying...
Dialogue: 0,0:00:03.18,0:00:05.23,Default,,0000,0000,0000,,As you'll see in our next video,
Dialogue: 0,0:00:05.24,0:00:09.35,Default,,0000,0000,0000,,the real action happens along the edges of the tectonic plates.
Dialogue: 0,0:00:09.71,0:00:13.21,Default,,0000,0000,0000,,So, now it's time to take a look at plate boundaries,
Dialogue: 0,0:00:13.22,0:00:15.52,Default,,0000,0000,0000,,sometimes also called plate margins,
Dialogue: 0,0:00:15.79,0:00:20.07,Default,,0000,0000,0000,,which are all of the parts of the world where one tectonic plate is next to another. (MUSIC).
Dialogue: 0,0:00:34.02,0:00:39.20,Default,,0000,0000,0000,,Constructive sometimes also called divergent plate boundaries exist in the parts
Dialogue: 0,0:00:39.21,0:00:42.41,Default,,0000,0000,0000,,of the world where magma is rising up in the mantle below,
Dialogue: 0,0:00:42.76,0:00:45.45,Default,,0000,0000,0000,,this rising magma cools off and spreads out.
Dialogue: 0,0:00:51.21,0:00:54.27,Default,,0000,0000,0000,,Some of it solidifies and creates new crust which begins
Dialogue: 0,0:00:54.28,0:00:57.43,Default,,0000,0000,0000,,to slowly move apart as two separate tectonic plates.
Dialogue: 0,0:00:58.45,0:01:01.83,Default,,0000,0000,0000,,These types of boundary mostly appear at the bottom of the sea.
Dialogue: 0,0:01:02.13,0:01:02.20,Default,,0000,0000,0000,,(Under the sea).
Dialogue: 0,0:01:03.27,0:01:05.62,Default,,0000,0000,0000,,There are some places like Iceland where you can actually
Dialogue: 0,0:01:05.63,0:01:09.82,Default,,0000,0000,0000,,see evidence on land of the tectonic plates splitting apart.
Dialogue: 0,0:01:09.99,0:01:13.37,Default,,0000,0000,0000,,So, what type of hazards do we find here and why?
Dialogue: 0,0:01:14.01,0:01:16.24,Default,,0000,0000,0000,,Let's start with volcanoes.
Dialogue: 0,0:01:16.47,0:01:20.22,Default,,0000,0000,0000,,Some of the magma along with gases like carbon dioxide can
Dialogue: 0,0:01:20.23,0:01:23.27,Default,,0000,0000,0000,,melt through the crust and get released out of the surface,
Dialogue: 0,0:01:23.77,0:01:26.74,Default,,0000,0000,0000,,which is basically what a volcanic eruption is.
Dialogue: 0,0:01:26.94,0:01:27.83,Default,,0000,0000,0000,,So, yeah,
Dialogue: 0,0:01:28.15,0:01:30.98,Default,,0000,0000,0000,,we get volcanoes often with lots of lava.
Dialogue: 0,0:01:31.90,0:01:34.58,Default,,0000,0000,0000,,Earthquakes do happen at constructive boundaries,
Dialogue: 0,0:01:34.59,0:01:36.81,Default,,0000,0000,0000,,but they aren't usually that powerful.
Dialogue: 0,0:01:36.94,0:01:39.88,Default,,0000,0000,0000,,You see an earthquake happens when tectonic plates
Dialogue: 0,0:01:39.89,0:01:42.28,Default,,0000,0000,0000,,get stuck or grind against each other.
Dialogue: 0,0:01:42.66,0:01:44.59,Default,,0000,0000,0000,,And it just doesn't happen very much at this kind
Dialogue: 0,0:01:44.60,0:01:47.19,Default,,0000,0000,0000,,of boundary because the plates are mostly moving apart.
Dialogue: 0,0:01:50.84,0:01:51.77,Default,,0000,0000,0000,,Destructive,
Dialogue: 0,0:01:51.78,0:01:55.46,Default,,0000,0000,0000,,sometimes also called convergent boundaries are areas where
Dialogue: 0,0:01:55.47,0:01:58.18,Default,,0000,0000,0000,,tectonic plates are being carried towards each other.
Dialogue: 0,0:01:58.28,0:02:00.58,Default,,0000,0000,0000,,But there are actually two different types.
Dialogue: 0,0:02:00.95,0:02:04.42,Default,,0000,0000,0000,,If an oceanic plate is moving towards a continental plate,
Dialogue: 0,0:02:04.52,0:02:06.80,Default,,0000,0000,0000,,the oceanic plate is forced underneath because it
Dialogue: 0,0:02:06.81,0:02:10.06,Default,,0000,0000,0000,,is denser in a process we call subduction.
Dialogue: 0,0:02:10.41,0:02:14.33,Default,,0000,0000,0000,,As the oceanic plate sinks into the mantle, water and things like
Dialogue: 0,0:02:14.34,0:02:17.11,Default,,0000,0000,0000,,dead plankton on the sea floor are dragged down with it.
Dialogue: 0,0:02:17.20,0:02:21.33,Default,,0000,0000,0000,,These are turned into water vapor and carbon dioxide which bubble upwards
Dialogue: 0,0:02:21.34,0:02:25.29,Default,,0000,0000,0000,,and melt through the continental crust above get trapped in the rock.
Dialogue: 0,0:02:25.30,0:02:29.46,Default,,0000,0000,0000,,Pressure begins to build up much like it does when you shake a bottle of fizzy drink,
Dialogue: 0,0:02:29.56,0:02:33.10,Default,,0000,0000,0000,,and eventually the pressure in the crust becomes too great and the gas
Dialogue: 0,0:02:33.11,0:02:36.79,Default,,0000,0000,0000,,and lava violently explode out of the rock in a volcanic eruption.
Dialogue: 0,0:02:37.87,0:02:42.06,Default,,0000,0000,0000,,Extremely powerful earthquakes can also happen in these destructive boundaries.
Dialogue: 0,0:02:42.08,0:02:45.91,Default,,0000,0000,0000,,The oceanic crust doesn't simply slide gently past a continental plate.
Dialogue: 0,0:02:46.22,0:02:49.13,Default,,0000,0000,0000,,These huge rough slabs of rock are constantly
Dialogue: 0,0:02:49.14,0:02:51.61,Default,,0000,0000,0000,,grinding against and getting stuck on each other.
Dialogue: 0,0:02:51.92,0:02:54.06,Default,,0000,0000,0000,,And when they do get stuck, the continental
Dialogue: 0,0:02:54.14,0:02:56.92,Default,,0000,0000,0000,,plate starts getting dragged down with the oceanic plate.
Dialogue: 0,0:02:57.40,0:03:00.14,Default,,0000,0000,0000,,It builds up a huge amount of energy as this happens.
Dialogue: 0,0:03:00.15,0:03:02.21,Default,,0000,0000,0000,,And when the plates finally become unstuck,
Dialogue: 0,0:03:02.40,0:03:04.17,Default,,0000,0000,0000,,the plate violently jumps upwards,
Dialogue: 0,0:03:04.18,0:03:08.39,Default,,0000,0000,0000,,releasing all of the stored energy and causing intense shaking in the ground.
Dialogue: 0,0:03:08.53,0:03:10.28,Default,,0000,0000,0000,,We know this as an earthquake.
Dialogue: 0,0:03:14.47,0:03:19.02,Default,,0000,0000,0000,,The second type of destructive plate boundary is known as a collision boundary.
Dialogue: 0,0:03:19.48,0:03:23.17,Default,,0000,0000,0000,,The big difference here is that both of the tectonic plates are continental,
Dialogue: 0,0:03:23.18,0:03:25.07,Default,,0000,0000,0000,,so they have roughly the same density.
Dialogue: 0,0:03:25.48,0:03:30.81,Default,,0000,0000,0000,,They crash head-on and crumple upwards, creating what we call fold mountains.
Dialogue: 0,0:03:31.72,0:03:35.10,Default,,0000,0000,0000,,You can see this is happening between tectonic plates like the Indian and
Dialogue: 0,0:03:35.11,0:03:40.22,Default,,0000,0000,0000,,Eurasian plates where the force of the two plates colliding has created a mighty
Dialogue: 0,0:03:40.40,0:03:41.98,Default,,0000,0000,0000,,Himalayas mountain range.
Dialogue: 0,0:03:43.53,0:03:47.62,Default,,0000,0000,0000,,As you can imagine, the process of forming a mountain range isn't as smooth.
Dialogue: 0,0:03:48.31,0:03:52.63,Default,,0000,0000,0000,,The plates grind and crack and buckle upwards over millions of years
Dialogue: 0,0:03:52.74,0:03:56.32,Default,,0000,0000,0000,,and at times they get locked together and get stuck on each other.
Dialogue: 0,0:03:56.71,0:04:00.57,Default,,0000,0000,0000,,Eventually, the plates build up enough energy to become unstuck.
Dialogue: 0,0:04:00.63,0:04:04.19,Default,,0000,0000,0000,,The plates jolt back into movement and an earthquake is created.
Dialogue: 0,0:04:04.80,0:04:08.03,Default,,0000,0000,0000,,Oh and don't confuse these mountains of volcanoes.
Dialogue: 0,0:04:08.57,0:04:10.85,Default,,0000,0000,0000,,There's no magma rising up from underneath them,
Dialogue: 0,0:04:10.86,0:04:14.69,Default,,0000,0000,0000,,so you don't get any volcanic eruptions at collision boundaries.
Dialogue: 0,0:04:18.82,0:04:21.40,Default,,0000,0000,0000,,Conservative boundaries, sometimes also called
Dialogue: 0,0:04:21.41,0:04:23.92,Default,,0000,0000,0000,,transform boundaries are so named because
Dialogue: 0,0:04:23.93,0:04:27.46,Default,,0000,0000,0000,,the tectonic plates are not being constructed or destroyed here,
Dialogue: 0,0:04:27.47,0:04:30.78,Default,,0000,0000,0000,,so it is conserved which means to be kept the way it is.
Dialogue: 0,0:04:31.05,0:04:33.72,Default,,0000,0000,0000,,These conservative boundaries happen at places where two
Dialogue: 0,0:04:33.73,0:04:36.08,Default,,0000,0000,0000,,tectonic plates are sliding past each other,
Dialogue: 0,0:04:36.46,0:04:40.68,Default,,0000,0000,0000,,either in opposite directions or in the same direction at different speeds.
Dialogue: 0,0:04:40.79,0:04:44.50,Default,,0000,0000,0000,,The edges of the plate get stuck on each other as they grind past and
Dialogue: 0,0:04:44.65,0:04:46.02,Default,,0000,0000,0000,,you probably know the rest by now,
Dialogue: 0,0:04:46.26,0:04:50.27,Default,,0000,0000,0000,,it builds up energy and after a while they jolt back into moving again
Dialogue: 0,0:04:50.43,0:04:53.91,Default,,0000,0000,0000,,and the energy gets released causing the ground to shake,
Dialogue: 0,0:04:54.08,0:04:54.77,Default,,0000,0000,0000,,earthquake.
Dialogue: 0,0:04:55.56,0:04:57.78,Default,,0000,0000,0000,,Following the same rules as before,
Dialogue: 0,0:04:57.79,0:05:02.03,Default,,0000,0000,0000,,there is no magma rising up underneath the crust at a boundary like this. So,
Dialogue: 0,0:05:02.17,0:05:03.00,Default,,0000,0000,0000,,you guessed it,
Dialogue: 0,0:05:03.39,0:05:04.72,Default,,0000,0000,0000,,no volcanoes.
Dialogue: 0,0:05:05.05,0:05:06.97,Default,,0000,0000,0000,,And that will be all for this video.
Dialogue: 0,0:05:07.84,0:05:10.52,Default,,0000,0000,0000,,As always thank you very much for tuning in
Dialogue: 0,0:05:10.53,0:05:14.33,Default,,0000,0000,0000,,and if you enjoy our content, please consider liking and subscribing
Dialogue: 0,0:05:14.50,0:05:15.24,Default,,0000,0000,0000,,and also
Dialogue: 0,0:05:15.67,0:05:19.81,Default,,0000,0000,0000,,hit the little bell ding if you wish to be notified every time we upload a new video.
Dialogue: 0,0:05:19.91,0:05:20.84,Default,,0000,0000,0000,,As always,
Dialogue: 0,0:05:20.85,0:05:25.00,Default,,0000,0000,0000,,you've been listening to The Mountain Man and watching the work of Michael Deluxe.
Dialogue: 0,0:05:25.08,0:05:25.94,Default,,0000,0000,0000,,Remember,
Dialogue: 0,0:05:26.23,0:05:27.18,Default,,0000,0000,0000,,keep it simple. (MUSIC).