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Year 7 Mastery Booklet YEAR 7 MASTERY BOOKLET Unit 2 – Terrifying Tectonics 2019-2020 ARK CURRICLUM PROJECT Unit 2: Terrifying Tectonics What will I be learning this unit? By the end of this unit you will know all about earthquakes and volcanoes – what causes them and their impacts. You will investigate two case studies and will make an important decision about reducing future risks. Lesson 1: What is happening beneath our feet? In this lesson we learn to describe the structure of the earth and to compare its layers. Lesson 2: Why are the plates moving? In this lesson we learn how convection currents are formed and how this causes tectonic plate movement. We will use global maps to identify the main tectonic plates. Lesson 3: What are tectonic hazards and where do they occur? In this lesson we will learn to describe the global distribution of earthquakes and volcanoes, using continents and compass directions. We will also begin to understand the connection between plate boundaries and tectonic hazard distribution. Lesson 4: What causes an earthquake? In this lesson we will solve the mystery of why an earthquake happened in Sichuan in 2008 using a series of clues related to physical features and tectonic processes. Lesson 5: What were the impacts of the 2008 earthquake at Sichuan? In this lesson we are learning to describe and categorise the impacts of the 2008 Sichuan earthquake. We will start to explain why the effects were very severe. Lesson 6: What causes a volcano? In this lesson we are learning why volcanoes form at destructive plate boundaries using the case study of Volcán de Fuego in Guatemala. Lesson 7: What were the impacts of Volcán de Fuego’s 2018 eruption? In this lesson we describe some hazards resulting from volcanic eruptions, using the case study of Volcán de Fuego. Some students might analyse how volcanic impacts vary depending on factors such as population density, preparedness and emission type. Lesson 8: How can hazards be managed? In this lesson we are learning to describe how earthquakes and volcanoes can be prepared for and managed afterwards. Using either Sichuan or Volcán de Fuego, students will make a justified decision about tectonic hazard management. Optional lessons Lesson 9: What causes a tsunami? In this lesson we will explore the physical processes that led to the formation of a tsunami, using the case study of Japan in 2011. You will use cross-sectional diagrams to help explain how the tsunami formed. Lesson 10: What were the impacts of and responses to the Japanese Tsunami in 2011? In this lesson we will describe the impacts of the Japanese tsunami including the damage to the nuclear powerplant and trade. 1 Glossary – Terrifying Tectonics Lesson 01 – What is happening beneath our feet? Core – Extremely hot metal Oceanic crust – sections of the crust compounds at the centre of the Earth. beneath the oceans. Mantle – Earth’s thick ‘middle’ layer, Magma – melted or semi-melted made up of very hot magma. rock. Crust – Earth’s thin outer layer, made Composition – what something is up of solid rock 7 – 100km thick. made up of, e.g. rock or magma. Continental crust – sections of crust Density – how dense (heavy) higher than ocean level. something is. Lesson 02 – Why are the plates moving? Tectonic plate – a large ‘slab’ of the Pangea – A ‘supercontinent’ existing crust. 250 million years ago, which slowly broke apart into seven continents. Plate boundary – the edge of a Continent – huge chunks of land. tectonic plate. It’s where most There are seven continents. earthquakes and volcanoes occur. Convection currents – the constant Tectonic plate theory – the idea that rising and sinking of magma in the over 250m years convection currents mantle as it heats and cools. caused Pangea to break apart. Lesson 03 – What are tectonic hazards and where do they occur? Tectonic hazard – a dangerous event Distribution – the way something is caused by tectonic plate movement spread out or arranged over a (e.g. earthquake or volcanic eruption). geographic area. Earthquake – sudden violent shaking of Cluster – a group, e.g. of earthquake the ground as a result of movements events. within the crust. Volcanic eruption – when lava and Pacific Ring of Fire –boundary of the other materials erupt through a hole in Pacific plate, so-named because the crust. many tectonic hazards occur here. Conservative boundary – where two Constructive boundary – where plates slide against each other. plates move apart, allowing magma to emerge and form (construct) new land. 2 Destructive boundary – where Hotspot – volcanic areas formed by continental and oceanic crust collide. exceptionally hot areas within the mantle. They form volcanoes far away from plate boundaries. Lesson 04 – What causes an earthquake? Focus – the location in the crust where Richter Scale – a scale measuring an the earthquake occurs. earthquake’s magnitude. Epicentre – the point on Earth’s Sichuan – a region in southern China surface where shaking feels strongest that is prone to earthquakes. (directly above the focus). Seismic waves – waves of energy that Fault – a weakness in the crust move outwards from the focus caused by pressure at the plate through the crust. boundary. Collision boundary – where two or Longmenshan fault – a weakness in more sections of continental crust the crust in Sichuan, caused by push towards each other. pressure at the Indian/Eurasian boundary. Lesson 05 – What were the impacts of the 2008 earthquake at Sichuan? Impact – another word for effect or Environmental impact – damage to consequence. the surroundings, e.g. bridges or forests. Social impact – something that affects Population density – how crowded a people, e.g. loss of life. place is, measured by the number of people per square kilometre. Economic impact – something that is Building collapse – the main cause of costly, generally for a government. death in the Sichuan quake; sometimes known as pancaking. Lesson 06 – What causes a volcano? Volcano – an opening in the Earth’s Crater – bowl-shaped basin in the crust. top of the volcano. Volcanic eruption – when lava, gases Subduction – when one section of and ash erupt through a volcano due crust pushes beneath another. The to tectonic plate movement. most dense plate subducts. Magma chamber – large underground Composite volcano – steep, pool of magma. explosive volcanoes made of ash and lava layers. They form at destructive boundaries. 3 Vent – central tunnel through the Volcán de Fuego – a very active volcano that magma travels through. composite volcano in Guatemala, near the Cocos/Caribbean boundary. Lesson 07 – What were the impacts of Volcán de Fuego’s 2018 eruption? Ash column – a large pillar of ash rising Evacuation – removing people from from the volcano, forming an ash cloud an unsafe area. above. Pyroclastic flows – extremely Warning signs – volcanoes usually dangerous, fast-moving flows of hot give off signs such as steam, gas, ash volcanic rock, gas and ash. clouds or bulging before they erupt. Lahars – volcanic mudflows. Slow- Agricultural land – land used for moving but powerful mixtures of lava, farming, e.g. tobacco farming land ash, pyroclastic flows and rain/ice. around Volcán de Fuego. Lesson 08 – How can hazards be managed? Management – something that is done Earthquake-proofing – making to reduce risks. buildings stronger to withstand an earthquake. Predict – use evidence to suggest that Monitoring – observing something to an event will happen. detect any signs that it will happen again. Prepare – get ready for something, e.g. Respond – action taken after an signposting evacuation routes. event, e.g. first aid for survivors. Lesson 09– What causes a tsunami? Tsunami – a wave caused by tectonic Displace – to move from its original movement under the sea floor. position. An earthquake under the sea floor displaces water which becomes the tsunami wave. Ocean – enormous body of water. Pacific plate – a huge oceanic plate There are five major oceans, e.g. which subducted under the plate Pacific. that Japan sits on, causing a major tsunami in 2011. Lesson 10 – What were the impacts of and responses to the Japanese Tsunami in 2011? Flooding – when land is land covered Fukushima – a city in Japan. A major by water. nuclear power plant there was damaged by the 2011 tsunami. Nuclear power plant – a site that uses Debris – scattered pieces of rubbish dangerous nuclear technology to or remains, e.g. chunks of houses generate energy. and broken trees left in the tsunami’s wake. 4 Lesson 01: What is happening beneath our feet? Task 2/Develop Learning: The crust Answer the following questions about continental and oceanic crust. 1. What type of crust exists at X? ______________ I know this because… 2. Is there more oceanic or continental crust? _____________ Give percentages! Task 3/Independent Task: Learning more about Earth’s layers Read Sections A and B before completing the tasks on the following page. Section A – More on the structure of the earth! After the earth formed, it was so hot inside the planet that everything melted. The densest (heaviest) materials sank to the core and the lighter substances rose. This process helped to form the earth’s layers. There are three major layers: core, mantle and crust. The characteristics of the layers vary (composition, thickness and temperature). The core is the hottest layer, with temperatures above 6000°C. The core is comprised mainly of iron and nickel compounds. It generates intense heat which keeps the mantle very hot. The mantle is the largest layer. It sits between the core and the crust and is 2900 km thick. It is made up of molten (melted and semi-melted) rock, called magma. When this rock erupts through the crust it is called lava. The crust is where we live. It is the thinnest layer and is made up of solid rock.
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