welcome to this aq8 GCSE geography revision blast this session is looking at tectonic hazards which is part of paper one the challenge of natural hazards so we're going to kick off the session with a game of altered vowels each of the key terms shown has the vowels change and alternative valves obviously they are all to do with tectonics can you work out the key phrase we'll pop each one of them screen for a few moments at any point if you need to pause to give yourself a little bit more time please do we will warn you when we're going to reveal our first one is on the screen now let's reveal it is a focus this is a point below the Earth's surface when the Rocks give way in an earthquake number two is on the screen now okay let's reveal it is the epicenter so this is the point directly above the focus where the earthquake hits worse number three is on our screen let's reveal is plate boundary also known as plate margins um you will hear you possibly will see both of those terms in your exam paper but we do tend to see plate margins more often now this is a point where two or more plates meet and therefore we would expect more tectonic activity okay our fourth one is on the screen let's reveal it's a Richter Scale this is a measure of magnitude of an earthquake however we don't tend to use a Richter Scale anymore it is seen as an outdated way of measuring earthquakes although you will still see it in your textbooks finally let's reveal is seismometer so this is a machine that measures the vibrations from an earthquake well done if you've got all five correct if there's any of those that you're not sure about uh go away and have a look at those definitions and try and remember those it's really important to learn your key terms okay moving on we have a 60 Second Challenge so on the left hand side you have eight terms to do with tectonics and on the right hand side you have got the definitions you have got one minute to match them up he might need a pen and paper at the ready here so matching letters to numbers good luck [Music] and again feel free to pause the video [Music] [Music] [Music] [Applause] [Music] thank you [Music] okay like we said during the music if you need to pause to give yourself a bit more time please do we are about to reveal the answers though foreign tectonic plate giant section of the Earth surface so lithosphere that's on the Move we've got convection current heat from the core causes material in the mantle to flow subduction where one plate is forced under the other which takes place at destructive plate boundaries magma is a molten rock that flows underground and when it's above ground we call it lava earthquake simply means the ground is shaking we've mentioned the epicenter already so it's a place on the surface where most of the damage is done and then we've got the Richter scale that old measure of the magnitude or the strength of an earthquake again well done if you've got all of those correct okay we are going to do a quick give me three you've got until the time goes on the timer to give me three types of plate margin good luck [Music] foreign [Music] 's up so let's reveal the three different types of plate margin so we have destructive we have constructive and we have conservative now it's really important that you know what happens at each one of these they're quite often the focus of four Mark questions on that paper one so a destructive plate boundary you've got two plates moving towards each other so they can either be continental plates moving towards each other and if that happens then they tend when they meet you tend to have fold mountains more often you have Oceanic and con um continental plates moving together oceanic plates get forced below that's called subduction here with a constructive plate margin you have two plates moving away from each other so you get giant rift valleys formed at a conservative plate boundaries you get two plates moving side to side either in the same direction at different speeds or in the opposite direction so what happens here is you can have huge bills up of pressure they get caught on each other like a bit like a zipper um and over time that pressure builds and it can leads a hugely powerful earthquakes so again make sure you know your different types of plate boundary or plate margin okay we're going to move on next to a bubble quiz so with a bubble quiz number of answers that are correct can range from zero to all four so you're going to have five questions you've got to just work out how many of the answers that we're showing you are correct here's our first one so a natural Hazard is a natural event threat to property problem created by people or a threat to people how many of those do you think are correct if you need a little bit more time at any point please pause the video if you need to let's reveal the answer it is a b and d so natural event a threat to property and a threat to people so it can't be classed as a natural Hazard unless there is that threat to property in people which of the following our tectonic Hazard so hopefully this is a nice easy one tropical storms organic eruptions earthquakes or tsunamis let's review the answer is all of them apart from tropical storm so b c and d tropical storms are a weather Hazard and we're going to cover those in a different revision blast where do earthquakes occur so we've got plate margins destructive margins constructive margins and conservative margins okay let's reveal the answer it is at all four of them now in contrast where do volcanic eruptions occur we've got hot spots destructive margins conservative margins and constructive margins what do we think again pause if you need a little bit more time we're about to reveal it is all of them apart from conservative margins so a conservative margins there is no magma which means that there is no volcanic activity hot spots are places like Hawaii so not anywhere near a plate boundary um but the crust of the um Earth is thin enough for the magma to break through and finally which areas have active volcanoes we've got Hawaii we've got the Pacific Ring of Fire we've got the Mid-Atlantic Ridge and we've got the San Andreas Fault okay pause if you need a little bit more time let's reveal super so Hawaii is part of a hot spot your Pacific Ring of Fire which goes right around the Pacific Plate you've got the Mid-Atlantic Ridge where you've got lots of um underground or I'm sorry underwater volcanoes and San Andreas fault has none because it is a conservative plate boundary which is goes down the side um goes along the edge of the USA sort of through California places like San Francisco and La for example right we're moving on to a connection wall so the connection wall has got 12 key terms they can be grouped into three groups of four what we'd like you to do is to find the connection so we'll leave it up for a moment on the screen as it is if you need more time you need to pause the video have a think about what they have in common so these can be grouped into three key phrases but it does say four on the screen we mean three that's a mistake so each of the three groups has four phrases in thinking you might want to get a pen and pencil or pen or pencil they're ready here to help you with this one it pause the video if you need a little bit more time on this activity have you spotted the three groups yet they are something that we have already referred to hopefully you have spotted the three groups are the different plate boundaries or the different plate margins so let's have a look at the answers and have a reveal again if you're not quite ready pause the video for a few moments for them to have a look at these groups so firstly we've got constructive plate margins so constructed plate margins move apart an example would be the Eurasian and the North American plates the Mid-Atlantic Ridge has formed a long constructed plate margin and you also get shield volcanoes are constructive plate margin we've then got destructive plate margins so an example would be the NASCAR and South American plates they move together subduction takes place and we have composite volcanoes so by process of elimination we've got our conservative plate margins that move side by side for example the Pacific and North American plates we've got the San Andreas fault that we've mentioned already and they don't have any magma that's why you don't have volcanoes along them okay let's move on to a true or false activity so hopefully if you've been paying attention these should be nice and easy so firstly tectonic plates move side by side at destructive margins is that true or false we'll leave it on for a moment let's reveal the answer it's false that's what happens at a conservative plate margin right tectonic plates move towards each other are destructive plate margin is that true or false let's reveal the answer it is of course true tectonic plates move away from each other are conservative plate margins now if you were listening literally 20 seconds ago you should know this answer let's reveal now it is false earthquakes are found at destructive plate margins is this true or false let's reveal the answer is true volcanoes are found a destructive plate margins is this true or false let's review it is true so a distracted plate margin when subduction takes place you've got the uh oceanic plate being pushed into the crust which sorry being pushed into the into the into the mantle which then melts causes that magma to occur right let's move on to a game of red herring so this time you're going to be shown for items and you need to say which is the odd one out and why so let's do our first one so which of the four items is the odd one out and why we've got our large we've got buildings collapse we've got Road surface rupture and we've got people injured by Falling masonry so if you need a little bit more time pause the video so one of these is the odd one out let's reveal which one it is it is an avalanche the others are primary effects of earthquakes let's do the second one okay this time we've got broken water pipes we've got Landslide we've got tsunami and we've got a food shortage so which one is the odd one out of Y let's reveal it is broken water pipes the others are secondary effects of earthquakes right so number three which is the odd one out in this one so fertile soil for farming job in the tourist industry becoming a film star geothermal energy so pause if you need to Let's reveal the answer it is see the others are reasons why people live near active volcanoes right number four which of the four items is the odd one out and why we've got reading your horoscope practicing School drills training search and rescue dogs and earthquake resistant building design which is the odd one out pause if you need to Let's reveal it is reading your horoscope obviously the other strategies to reduce the risk created by earthquake so perhapsing School drawers in particular really good example of that is in um Japan where every September they have an earthquake drill day a bit like we would have fire drills in the UK right number five which of the four items here's the odd one out and why we've got measuring the temperatures of local Rivers monitoring earthquakes keeping a look out and testing gases released nearby which of those four is doesn't match the others let's reveal it is keeping a look out so scientific methods used to predict volcano volcanic eruptions are the other ones there okay we now have two minutes to answer this five four three two one activity so let's have a look at what you've got to note down in that time so a lot to do in two minutes so you might need to pause the time four three two one [Music] okay so this one we're actually looking at in the pool earthquake which lots of you do as a caterly if you've got a different one you can obviously do uh you can tailor your responses for that so why with the pool at this point in 2015 five reasons four reasons why the 2015 quarter point is so devastating free primary effect two second reflex and one and one side the responsible so two minutes but again if you need some time [Music] thank you [Music] thank you five four three two one [Music] okay how did you get on if you need to pause the video please do that now because we are about to reveal the answers hey let's have a look at five reasons why Nepal was at risk of a natural disaster in 2015. firstly it's on a plate margin there are many remote communities in rural areas poorly constructed all the buildings steep Mountain slopes and it is in well it's a low-income country so lots of factors there that would mean that it was less resilient to tectonic activity than other places the four reasons why the Gorka Quake was so devastating so it had a magnitude of 7.8 so anything over six is generally uh does generally result in loss of life particularly if it's over seven then it will be quite you know that death toll will be high which it was in this case shallow focus at a depth of a hunt of 15 kilometers so there's not much of that energy has been absorbed before it reaches the Earth's surface the epicenter was 80 kilometers away from the capital city of Kathmandu again not very far so there's lots of damage done there and it was climbing season in Mount Everest which meant that there were more people in the area than usual three primary impacts of the earthquake so we had a death toll of nine thousand people it's quite a large death toll for an earthquake lots of historic buildings were destroyed in the world heritage site in Kathmandu and more than a million people were made homeless to impact secondary impacts of the earthquake The Avalanches killed 19 climbers and there was a loss of income from tourism so Kathmandu took a really long time to get back on its feet after this and one sign that the responsible inadequate were a third of people affected were still in temporary housing in 2018 which is three years later right we're going to move on to a connection spinner activity now we're going to have a look at why people choose to live in areas at risk of tectonic activity we have six factors on the board so I put in design poverty water supply infrequent events ports and farming so why do people live in areas of risk of tetronegativity let's have a look at what hospital is going to land Okay so we've got Port this is our first one so have a think for a moment about how ports has a link to why people would live in areas at risk of tectonic activity I'm gonna leave it on the screen for a moment before you reveal the answer what do we have what do we think how are ports relevant here right let's reveal so plate margins often occur on the coastline where settlements have been built up around trading links so when we think back to a few hundred years ago when people were exploring if Europe they generally set up settlements in the first place places that they got to that's why you've got great big settlements along the coastline particularly in places like South America right where are we gonna land this time okay so everyone's on farming this time so what is a link here so why do people live in areas at risk of uh tectonic activity what's the links of farming let's give you a moment okay let's read the answer some areas around volcanoes have really rich fertile soils which is caused by the weathering of dried lava so although it is very risky to live there after a volcanic event then you will have the benefit of those sores becoming richer and more fertile so therefore more people can grow on them however there is also obviously a huge risk of a lava flow wiping out all the crops in the first place okay let's spin again okay this time we're on building designs so have a little think about this one so how does building design factor in here so pause if you need to Let's reveal the answer so building design means that buildings can withstand earthquake so again if we think about Japan so one of the world's richest countries but also frequently suffers from earthquakes so with things like cross bracing so when you've got a big steel frame that goes right across the building the way sort of holds it together you've got rolling weights now rolling weights go with something else so those great big skyscrapers that you see in Tokyo have a huge um big shock absorbers built in their foundations which means when the earth starts to vibrate when it when the volcano when sorry when the earthquake is happening then rather than just collapsing those buildings will sway however the rolling weight is on the roof of the building stops the swaying from beginning out of control you also tend to have things like um automatic shutters on these bones as well so as soon as it detects the vibration the shuttles will come down on the inside and outside so if any of the windows break during that um that shaking then all of the glasses sort of safely trapped between those two shutters meaning it isn't going to damage it's not going to cause harm to people right let's move on to the Stepping Stones activity so a bit more of a challenge here we're going to complete a chain of analysis to illustrate how we can mitigate risk of tectonic activities so let's have a look at what we want you to do here right on the screen you have five boxes two of them have been covered for you so you have got there are a number of ways that we can mitigate the risk of tectonic hazards at the top and then right at the bottom we've got these will decrease the potential social and economic impacts of tectonic hazards and they will keep the death toll low so what we need is a three boxes in between like the stepping stones from the start of an answer to the end of an answer so we might want to treat this a bit light perhaps a four mark question in the exam paper and the exam paper could be explain how we can mitigate the risk of tectonic hazards so it would be a good idea now to pause the video what we need you to do is to note down what you possibly could have write in those four boxes to connect to construct a chain of reasoning that would get you from there are a number of ways that we can mitigate the risk of tectonic hazards these will decrease the potential social and economic impacts of tectonic hazards and they'll keep the death toll low so while you're pausing the video perhaps think about using some examples think about the different ways that you can mitigate risk once you're ready restart and we will reveal those answers right let's have a look at how you got on so we reveal our second box we can monitor areas at risk using equipment such as seismometers to detect movements underground to help predict an event let's look at our third box in areas of risk we can protect buildings by using shock absorbers to make the building suite rather than collapse and I'm rolling weights they don't sway too much and then our last box we can also make plans such as practicing earthquake drawers like they do in Japan and stocking up on supplies so we are fully prepared in an event now if we have a look we've got our introductory statement we've got our little concluding statement right at the end and there are three boxes cover prediction they cover protection in the middle and then our fourth box down is planning so the idea of that MP3 so monitoring prediction protection and planning all part of how we would mitigate the risk of tectonic activity right I'm gonna now move on to a 10 second blast off so you're going to see some questions on the screen you've got 10 seconds to answer them foreign now the magnitude of earthquakes can be measured by the Richter Scale which is a logarithmic scale what does this mean now I'm just going to add a little caveat here we have generally stopped using the Richter Scale we still measure uh magnitude but we don't generally refer to the Richter Scale anymore but it is something that is probably still in your textbook so it's something that you will have heard of before but it's a lot of the rhythmic scale what does this mean liftoff will start in Q minus 10 seconds right it means that it's a whole number jump on the scale indicates a tenfold increase in power so for example an earthquake with a magnitude of seven is ten times more powerful than one with a magnitude of six and therefore it is a hundred times more powerful than a magnitude 5 earthquake second one which is more power so how much more powerful is an earthquake with a magnitude of eight than the earthquake with a magnitude of force a bit of mass going on here ten nine eight seven six five four three two one all right let's see if you've managed to work this one out is ten thousand times more powerful so magnitude for earthquakes don't really cause much damage they might knock the odd roof tile offer you know off a building it feels a bit like a a lorry rumbling partial house in terms of vibrations whereas eight is generally widespread Devastation huge death toll you know pretty much the buildings Race To The Ground all sorts of things plate margin is a city with volcanic eruptions ten nine eight seven six five four three two one okay so conservative note magma right that's the end of this revision Blast for tectonic hazards hopefully that's giving you a little bit more confidence with this unit if you have a look at the playlist We have got a revision Blast for all topics they might not be there at the moment but over the next few weeks they will all be added to so before your exams please have a watch of all of them and obviously good luck