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GCSE Geography Unit One: The Restless Earth Question 1. The Restless Earth Revision Checklist: 1. Read through your notes and tick off whether you have notes on the topics that have been covered. If not, you must copy up ASAP. 2. For each topic you must provide a score to reflect how well you think you understand what you’ve covered. This will help you focus your revision. Provide a score of 1-5. 3. Identify the topics you most need to revise – and do this as a priority! 1 = Don’t understand 3 = Understand some 5 = Understand all Section of Topic Pages: PLATE MARGINS: Tectonic plates: the distribution, and contrasts between continental and oceanic. 3/4 Plate margins: destructive, constructive and conservative. TECTONIC LANDFORMS: Location & formation: fold mountains, ocean trenches, composite volcanoes and shield volcanoes. 3/4 FOLD MOUNTAIN RANGE CASE STUDY: Case study: the ways in which the range is used – farming, hydroelectric power, mining, tourism and how people adapt to limited communications, steep relief & poor soils. 4/5 VOLCANOES: Characteristics: shield, composite and supervolcanoes. 6/7 Case study: of a volcanic eruption – the causes, primary & secondary effects, positive & negative effects, immediate & long term responses. Management: monitoring and predicting volcanic eruptions. SUPERVOLCANOES: Characteristics: The characteristics of a supervolcano and the likely effects of an eruption (social, environmental, economic & global, local, national). 8 EARTHQUAKES: Effects & responses: how the effects of an earthquake, and the responses to an earthquake vary between more economically and less economically developed countries. 9/10 Case study: A case study of an earthquake in a rich part of the world – their specific causes; primary and secondary effects; immediate and long-term responses – the need to predict, protect and prepare. Case study: A case study of an earthquake in a poor part of the world – their specific causes; primary and secondary effects; immediate and long-term responses – the need to predict, protect and prepare. TSUNAMIS: Case study: A case study to show the causes, effects, and responses. 11 Understanding? Tectonics Can you provide definitions for the following key terms? Inner core, outer core, mantle, convection current, crust, oceanic, continental, subduct, ocean trench, fold mountain, natural hazard, composite and shield volcanoes, magma, lava, crater, magma chamber, volcanic bombs, lahar, pyroclastic flow, tiltmeter, supervolcano, caldera, fissure, geothermal, geyser, hotspot, subsistence farming, irrigation, terraces, HEP, focus, epicentre, primary/secondary/surface seismic waves, magnitude, Richter scale, Mercalli scale, predication, protection, preparation, tsunami, primary effect, secondary effect, immediate response, long-term response, aid. http://www.bbc.co.uk/learningzone/clips/topics/secondary/geography/natura l_hazards_tectonic_activity.shtml Structure of the Earth The earth consists of four concentric layers; inner core, outer core, mantle and crust. The inner core: the centre of the earth and is the hottest part it is solid iron and nickel with temperatures of up to 6500°C. with its immense heat energy, the inner core is like the engine room of the Earth. The outer core: surrounds the inner core it is a liquid layer of iron and nickel temperatures around 5,500°C at the boundary with the mantle. The mantle: is the widest section of the earth it is made up of semi-molten rock called magma it is the convection currents within the magma that cause continental drift The crust: is the outer layer of the earth. it is a thin layer between 0-70km thick. there are two different types of crust: the less dense continental crust and the denser oceanic crust. Convection currents Continental drift / plate movement is caused by convection currents within the mantle the temperature at the boundary of the outer core & the mantle is about 5,500°C. the magma here is heated, becomes less dense and rises towards the crust. as it rises the magma cools, becomes denser & drags the plates along the surface of the mantle as it sinks. This cycle is repeated forming a convection cells. Plates and plate boundaries The surface of the earth is like a jigsaw made up of plates There are 2 types of plate: Oceanic – new material (igneous), dense Continental – older material (igneous, metamorphic and sedimentary rocks), less dense The point where two plates meet is called a plate boundary. Earthquakes and volcanoes are most likely to occur either on or near plate boundaries. Types of plate boundary The earth's plates move in different directions. Plates behave differently at different plate boundaries: Plate Boundary Constructive plate boundaries Destructive plate boundaries Diagram Description Example Constructive plate boundaries occur when two plates move away from each other North American and Eurasian Plate Destructive plate boundaries occur when an oceanic plate is forced under (or subducts) a continental plate Nazca and the S. American Plate Conservative plate boundaries Collision plate boundaries Conservative plate boundaries occur when two plates slide past each other. North American Plate and the Pacific Plate Collision plate boundaries occur when two continental plates move towards each other. IndoAustralian and the Eurasian Plate What happens at a constructive boundary? Eg. N. American and Eurasian Plates forming the Mid-Atlantic Ridge Plate movement Ocean ridge Volcanic islands Oceanic crust Mantle Seafloor spreading the plates are forced apart by convection currents in the mantle. Magma rises from the mantle, reaches the surface, cools and solidifies to form new crust made up of igneous rock. This process is repeated many times forming mid-ocean ridges e.g. the Mid-Atlantic Ridge on the boundary of the N. American & Eurasian plate & shield volcanoes like Surtsey and island arcs like the Lesser Antilles MID-OCEAN RIDGES Rift Valley mid-ocean ridge is general term for an underwater mountain system formed at a constructive plate boundary. This type of oceanic ridge is characteristic of seafloor spreading. The mid-ocean ridges of the world are connected and form a single global mid-oceanic ridge system that is part of every ocean What happens at a destructive boundary? E.g. The Juan de Fuca Plate & the N. American Plate forming the Cascade Range & Mount St Helen’s, USA Plate movement Fold mountains & composite volcanoes Continental plate Oceanic plate Subduction zone mantle the plates move towards each other on the surface this forms a trench at the point where the 2 plates meet & fold mountains formed as the sediment on the sea bed is uplifted this uplifted sediment forms fold mountains the oceanic plate is denser than the continental plate & is forced underneath (subducted) the continental plate. The point at which this happens is called the subduction zone. the subducted oceanic plate pulls sea water with it as it sinks into the mantle the water turns to steam and this combines with the melting plate to form explosive magma. This magma then rises up through cracks in the continental crust eventually forming composite volcanoes. OCEAN TRENCHES CONTINENTAL SLOPE: The continental slope gradually rises from the abyssal plains but climbs as much as 45 degrees as it approaches land. CONTINENTAL SHELF: The continental shelf, the region from the coastline to the edge of the continental slope, covers about eight percent of the global seafloor area. The continental shelf is a national asset for most nations. It is a source of fish, both commercial and sport, and in some areas, oil and natural gas ABYSSAL PLAINS: Abyssal plains are found next to the continental slopes at depths greater than 9 - 10,000 feet. They are areas of near freezing water temperatures where there is no season or sunlight. The Abyssal plain is regarded as the true ocean floor. The few marine inhabitants found in the region survive only because they have adapted to the hostile environment of bitter cold and immense pressure. What happens at a conservative boundary? e.g. Pacific & N. American Plates forming the San Andreas Fault the plates move parallel to each other, get stuck, pressure builds and is suddenly released in earthquakes the landscape has a crumpled appearance no land is created at a conservative boundary and none is destroyed. volcanoes do not occur along these boundaries earthquakes are very common. What happens at a Collision Plate Boundary? E.g. The Indo-Australian & the Eurasian plates forming the Himalayas an area of sea separates two continental plates, sediment is eroded and weathered from the land & settles on the sea floor in depressions called geosynclines. these sediments gradually become compressed into sedimentary rock. the two continental plates move towards each other, compressing the layers of sedimentary rock on the sea floor which become crumpled and folded to form fold mountains eventually the sedimentary rock appears above sea level as a range of fold mountains. Where the rocks are folded upwards, they are called anticlines. Where the rocks are folded downwards, they are called synclines. earthquakes are common at such boundaries The Andes Fold Mountains Background: Location: The Andes formed at the destructive plate boundary between the Nazca & S.American Plates The world's longest fold mountain range running for over 7,000km and covering 6 countries. Farming: best land can be found on the valley floors Tourism: terraces have been dug into the valley sides and held up by retaining walls has been used to bring the lands on the valley sides into food production. most crops are grown in the lower areas and include soya, maize, rice and cotton the main crop of the Andes is the potato most farming is subsistence, Llamas have historically been used a lot in the Andes, as a form of transportation and to carry goods. The Inca Trail Alpaca, a relative of the Llama, has been used to produce some of the finest cloth known to man, and is Tourism is a key industry for Peru in the East you can take part in Eco-tourism activities in the Amazon Basin, as found along the Madre De Dios River near to Puerto Maldonado. Peru has some fantastic coastline as well, but the highlight of Peru is undoubtedly the Inca Trail. also produced in the Andes mountains covers 50km of old pathways linking together old Inca settlements in the inhospitable mountains of the Andes. South America's best known trek and is one of only 23 World Heritage Sites The route takes 4 days and covers around 45km, and finishes with sunrise at the "Lost City of the Incas" at Machu Picchu the trail is strictly controlled, and only 200 trekkers are allowed to start out on the trail every day. Mining: The Andes mountains contain a wide range of minable materials There are large deposits of coal, oil and natural gas, iron ore, gold, silver, tin, copper, phosphates and nitrates and Bauxite The Yanacocha gold mine in Peru is the largest gold mine in the world an open cast mine and the rocks containing the gold are blasted with dynamite. The nearby town of Cajamarca has grown from 30,000 when the mine started to 240,000 people in 2005. HEP: deep river give the Andes huge potential as a region to produce hydroelectric power narrow valleys cut dam costs the steep relief increases water velocities allowing electricity generation Snow melt fuels most of the water provision - but this means that HEP production can be reduced to small amounts in winter. The El Platinal Project is under construction in Peru & will join the Yuncan dam The Alps Background: Location: High mountain ranges, e.g. Mont Blanc which is 4810m above sea level Contrasting microclimates on north facing (ubac) and south facing (adrete) slopes. Geologically young (30 – 40 million years old). Located in France, Switzerland, Austria & Slovenia Farming Most farms located on sunnier south-facing slopes Traditional system is Called Tourism: Tourism is a key industry transhumance – cattle taken up into alpine pastures during summer & brought back down to the valleys for the winter Farmers now use artificial feeds some livestock often stay in the All year round – hiking, climbing & winter sports For winter tourism (St Moritz & Chamonix) valleys all year Flatter land at higher levels easy for building hotels etc. Steep slopes above resorts for ski runs For summer tourism: Large glacial lakes on valley floors Beautiful mountain scenery Chocolate box villages Good transport links throughout Europe High numbers of tourist are damaging the environment Forestry Forestry on north-facing slopes Wood has always been the main building material Sawmills are located on valley floors Timber not used for construction turned into paper, pulp & fuel HEP: Narrow valleys are easy to dam Hep used to power sawmills & a range of industries A textbook volcano Composite & shield volcanoes COMPOSITE VOLCANOES Tall cone with narrow base & steep SHIELD VOLCANOES Cone with wide base & gentle slopes Basic lava Regular eruptions of little violence Occur sides Made of alternate layers of lava & ash Long periods of dormancy followed by explosive eruptions Occur at destructive plate boundaries on constructive boundaries Mt St Helen’s, USA Hekla & Surtsey in Iceland Soufriere hills, Montserrat Mauna Loa & Kilauea in Hawaii plate MOUNT ST HELEN’S VOLCANO A Case Study of a volcanic eruption in a richer country Background info: Mt St Helen’s is in a range of fold mountains called the Cascade Range in Washington State, USA It is a composite volcano Key Events: March 1980 - earthquakes followed by ash & steam eruption From March a bulge grew on the northern flank of the mountain 08.32 on 18th May 1980 an 5.2 earthquake caused a landslide on NE side of the mountain causing a lateral blast in the form of a pyroclastic flow - blast removes 390m summit Glaciers melted & formed lahars which swept away trees and rock choking rivers 2010 -A new magma dome is growing Causes: Cascades have been formed by a destructive plate boundary The Juan de Fuca Plate is being subducted beneath the North American Plate Primary Effects: Total destruction up to 27km north of crater 57 dead - had it not been a Sunday, the number would have been greater crops were ruined and livelihoods of loggers were devastated with large areas of trees being flattened like matchsticks – 15000 acres destroyed lava flows and ash filling in Spirit Lake and log jams and ash blocking the channel of the Toutle River Secondary Effects: Ash fell over 3 states causing havoc in towns like Yakoma, Washington Ash fall caused poor visibility on highways causing accidents Power lines came down causing power cuts Toutle & Colombia Rivers filled with ash & debris Unemployment in the immediate area rose tenfold in the following weeks Damage estimated at over £800 million Soil will become fertile in time Short-term Responses: USGS monitored volcano 11km exclusion zone was set up around the crater based on previous eruptions National Guard helicopters mobilized for search & rescue Washington State introduced a 15kmph speed limit & encouraged people to stay indoors Long-term Responses: US government gave $951million in aid to rebuild the local economy & compensate people Roads & bridges rebuilt, rivers dredged Forest is being replanted & recolonized naturally The area was given National Monument status in 1982 and received $1.4 million for development - it draws 3 million tourists / year Damage to forests & debris from lahars & pyroclastic flows has increased the risk of flooding in the area SOUFRIERE HILLS VOLCANO, MONTSERRAT A Case Study of a Volcanic Eruption in a poorer country Background info: Montserrat is part of the Lesser Antilles Population 11,000 before eruption First eruption July 1995 - still active Causes: Montserrat sits on a destructive plate boundary The North & South American Plates are being subducted under the Caribbean Plate Primary Effects: Secondary Effects: July 1995 - ash eruption. Now 2/3 island covered in ash August 1997 - pyroclastic flows 19 dead, two thirds of houses in Plymouth destroyed. Forest fires rage Pyroclastic flows & lahars block valleys & cause flooding Many schools destroyed Tourism ceased Crops destroyed by ash 15 square miles in north of island considered safe zone Short-term Responses: Long-term Responses: USGS monitored volcano & set up warning systems August 1995 - Safe Zone was set up in the north of the island UK government sent £17 million in aid including temporary buildings & water purification systems People began to emigrate - by 1997 the population had dropped to 3500 USA & Royal Navy helped with evacuation As most of the southern area was destroyed any remaining inhabitants have had to endure harsh living conditions in the North. Transport remains a problem for people travelling to the island as the port and airport remain closed. The tourist industry is still suffering with few visitors except for cruise ships looking at the volcano 3,000 people have not returned People moved back - current population is about 8,000 UK government funded a 3 year development programme - schools, houses, medical facilities, infrastructure - cost £122.8million Vegetation is growing back in south part of the island Soufriere Hills has become a tourist attraction Why do people live near volcanoes? 1. Time - most volcanoes are perfectly safe for long periods in between eruptions, and those that do erupt more frequently are usually thought of, by the people who live there, as being predictable - about 500 million people live 2. Minerals - copper, gold, silver, lead and zinc are associated with rocks found deep below extinct volcanoes. Hot gasses escaping through vents also bring minerals to the surface, notably sulphur, which collects around the vents as it condenses and solidifies. Locals collect the sulphur and sell it. 3. Geothermal Energy - Countries such as Iceland make extensive use of geothermal power, with approximately two thirds of Iceland's electricity coming from steam-powered turbines. It is a clean, sustainable source of energy 4. Fertile Soils – volcanic rock is mineral rich & weathers into rich soils.. 5. Tourism -Around the volcano may be warm bathing lakes, hot springs, bubbling mud pools and steam vents. Geysers are always popular tourist attractions, such as Old Faithful in the Yellowstone National Park, USA. Iceland markets itself as a land of fire and ice, attracting tourists with a mix of volcanoes and glaciers, often both in the same place. How are super volcanoes formed? Super volcanoes erupt infrequently They emit at least 1,000km3 – 1,ooo times more than Mt St Helen’s They do not have cones, but are huge basins called calderas Super volcanoes form over hotspots Magma rises from the hotspot & uplifting the crust into a dome Cracks appear on the surface – gas, lava & ash erupt from the magma chamber As the magma chamber empties the dome collapses forming the caldera YELLOWSTONE NATIONAL PARK SUPER VOLCANO A Case Study Background info: Causes: Super volcanoes emit at least 1000km2 of material Do not have a cone Form in a caldera (basin) often bordered by high ridges Super volcanoes do not occur at plate boundaries but over hot spots within plates Yellowstone National Park is in the USA It erupts about every 630,000 years & is due Potential Effects: The destruction of 10,000km2 87,000 dead 15cm of ash would cover settlements within 1000km bringing the economy to a standstill 1 in 3 people affected will die Transport, electricity, water & agriculture will be affected Ask would fall on UK five days later Global climate would be affected - temps would drop between 3 & 5 degrees Celsius Crops would fail & famine would follow Yellowstone National Park is sitting above a hot spot It has a magma chamber 80 km long, 40km wide & 8 km deep This is currently rising at around 70cm a year below Yellowstone lake Geothermal activity is responsible for geysers such as Old faithful Potential Responses: Emergency planning by US government based on USGS predictions UN led relief effort Migration from countries affected by famines especially in poorer parts of the world Increased regional tensions possibly leading to war Managing tectonic hazards – prediction, protection & preparation It's not possible to prevent earthquakes and volcanic eruptions. However, careful management of these hazards can minimise the damage that they cause. Prediction is the most important aspect of this, as this gives people time to evacuate the area and make preparations for the event. Predicting & monitoring eruptions As a volcano becomes active, it gives off a number of warning signs. These warning signs are picked up by volcanologists (experts who study volcanoes) and the volcano is monitored. The key techniques for monitoring a volcano Warning signs Monitoring techniques Hundreds of small earthquakes are caused as magma rises up through cracks in the Earth's crust. Seismometers are used to detect earthquakes. Temperatures around the volcano rise as activity increases. Thermal imaging techniques and satellite cameras can be used to detect heat around a volcano When a volcano is close to erupting it starts to release gases. The higher the sulfur content of these gases, the closer the volcano is to erupting. Gas samples may be taken and chemical sensors used to measure sulphur levels. Preparing for an eruption A detailed plan is needed for dealing with a possible eruption. Everyone who could be affected needs to know the plan and what they should do if it needs to be put into action. Planning for a volcanic eruption includes: Creating an exclusion zone around the volcano. Being ready and able to evacuate residents. Having an emergency supply of basic provisions, such as food. Funds need to be available to deal with the emergency and a good communication system needs to be in place. EARTHQUAKES What causes an earthquake? An earthquake is the shaking and vibration of the Earth's crust due to movement of the Earth's plates (plate tectonics) Earthquakes can happen along any type of plate boundary. Earthquakes occur when tension is released from inside the crust. Plates do not always move smoothly alongside each other and sometimes get stuck. When this happens pressure builds up. When this pressure is eventually released, an earthquake tends to occur. The point inside the crust where the pressure is released is called the focus. The point on the Earth's surface above the focus is called the epicentre. Earthquake energy is released in seismic waves. These waves spread out from the focus. The waves are felt most strongly at the epicentre, becoming less strong as they travel further away. Measurement of earthquakes The Richter Scale This measures magnitude An earthquake's magnitude (power) is measured using an instrument called a seismometer. The scale is logarithmic – there is a tenfold increase in power every time the scale increases by 1 So a scale of 2 is 10 times more powerful than 1 and a scale of 3 is 100 times more powerful than 1 The Mercalli Scale Measures the effects (damage) of an earthquake using a scale between 1 & 12 It is based on subjective descriptions – good for on the scene analysis of damage for emergency response What factors affect the impact of an earthquake? Distance from the epicentre Rock type – resistant rocks provide more solid foundations for buildings Magnitude - the higher on the Richter scale, the more severe the earthquake is. Level of development – richer countries are more likely to have the resources and technology for monitoring, prediction and response. Population density (rural or urban area). The more densely populated an area, the more likely there are to be deaths and casualties. Communication - accessibility for rescue teams. Time of day - influences whether people are in their homes, at work or travelling. The time of year and climate will influence survival rates and the rate at which disease can spread. NB: As a rule, the poorer the country, the greater the impact of the disaster KOBE EARTHQUAKE A case study of an earthquake in a richer country Background info: Physical Causes: Kobe is an important industrial city located on Honshu Island, Japan 17TH January 1995 - 05.46am – many were in bed 7.2 Ricter Scale - 20 seconds duration Kobe sits on the Nojima Fault Line on a destructive plate boundary between the Philippines & Eurasian Plates Shallow focus – 20km beneath Awaji Shima Island in the bay of Kobe 7.2 Richter Scale – 20 seconds duration 05.46am meant many in bed Human Causes Buildings built close together – domino effect Buildings built before 1981 were not earthquake proof SICUAN EARTHQUAKE, CHINA A Case Study of an Earthquake in a poorer country Background info: Sichuan is in China - an LEDC 12th May 2008 at 2.28pm 7.9 Richter Scale - duration 120seconds 200 aftershocks - 3 measuring over 6 Richter scale Epicentre near Wenchuan Primary Effects: 69,000 dead 18,000 missing 374,000 injured 5 million homeless Wenchuan cut off by landslides Beichuan - 80% buildings damaged Shifang -chemical plants collapsed killing thousands & spilling toxic waste 900 schools collapsed Physical Causes: Sichuan sits on a collision Plate boundary The Indo-Australian Plate is colliding with the Eurasian Sichuan is a mountainous province & prone to landslides Human Causes: LEDC – poor quality construction Limited emergency response services Secondary Effects: Many dams were damaged & power supplies cut Landslides cut roads & blocked rivers leading to fears of flooding 5,000 tents flown in on DFID flights 5,000 villages cut off daunting task of rebuilding communities and livelihoods 1 million left unemployed Reconstruction costs put at $150 billion Short-term Responses: Long-term Responses: Heavy rains & mudslides made rescue Over a million temporary homes difficult constructed in Sichuan over 3 years 20 helicopters sent to disaster areas Chinese government pledged 50,000 soldiers sent - some troops £10million to rebuild area were parachuted in – not emergency Banks wrote off debts search & rescue specialists Dams & infrastructure rebuilt Shelter, food & water provided Schools rebuilt on steel pole Land flattened for camps - 3million foundations & lightweight thatch tents called for 14th May China asked for international help by text message Red Cross donated £100 million in aid The Haiti Earthquake 2010 A Case Study of an Earthquake in a poorer country Background info: Location: Caribbean nation of Haiti- 15km (10 miles) south-west of Port-au-Prince ( capital of Haiti) Date: Tuesday 12th January 2010 Time: 16.53 (21.53 GMT) Size: shallow focus earthquake Depth of 13 km. 7.0 on Richter scale. Aftershocks between 5.0 and 5.9. Destructive Plate Boundary: N. American plate is being subducted below the Caribbean plate Physical Causes: A shallow focus earthquake The fault line hadn’t moved for 250 years – people were unprepared Human Causes: Primary Effects: The port was destroyed hampering aid response Water supplies & power cut an estimated three million people were affected by the quake between 217,000 and 230,000 people died an estimated 300,000 injured an estimated 1,000,000 homeless 250,000 residences and 30,000 commercial buildings had collapsed or were severely damaged. The epicentre of the earthquake was 16km south west of Port-AuPrince Haiti is the poorest country in the Western Hemisphere The buildings in Port-Au-Prince and other areas of Haiti were in very poor condition in general and were not designed or constructed to be earthquake resistant. 3 Million people live in Port au Prince with the majority living in slum conditions after rapid urbanisation. Haiti only has one airport with one runway. The control tower was badly damaged in the earthquake. The port is also unusable due to damage Secondary Effects: Communication systems, air, land, and sea transport facilities, hospitals, and electrical networks had been damaged by the earthquake, which hampered rescue and aid efforts; confusion over who was in charge, air traffic congestion, Lack of aid & police force caused violence Medical treatment was hampered by lack of power and shortages of equipment and medical supplies. A cholera epidemic broke out due to unclean drinking water in refugee camps Short-term Responses: 400,000 water bottles & 300,000 food rations dropped in first 9 days Bodies buried in mass graves Aid supplies flown into the Dominican Republic and taken across the border by convoy Huge international aid response coordinated by the UN The UK government has sent eight mobile medical units along with 36 doctors including orthopaedic specialists, traumatologists, anaesthetists, and surgeons. In addition, 39 trucks with canned food have been dispatched, along with 10 mobile kitchens and 110 cooks capable of producing 100,000 meals per day. Long-term Responses: Estimated that over 1,000 aid agencies are involved in the reconstruction Unrest as little progress appears to have been made The Asian Tsunami 2004 A Case Study of a tsunami in a poorer region Tsunamis are usually caused by earthquakes. The crust moves and the water displaced forms the wave As the waves approaches land the wavelength decreases while the height increases Background info: 26 Dec. 2004 The highest wave to come ashore was 25m Areas worst affected included Sri Lanka, Indonesia (especially Sumatra) & Thailand Physical Causes: USGS recorded 9.1 on Richter Scale Destructive plate boundary – the Indo-Australian is being subducted below the Eurasian plate Human Causes: Primary Effects: Over 220,000 died 650,000 were seriously injured 2 million made homeless 1,500 settlements completely destroyed in Banda Aceh alone Short-term Responses: Bodies were buried in mass graves The army was mobilised Huge international aid effort began – water purification tablets, food, sheeting for tents etc. Uk’s gov promised £75million following £100million raised by the public High density of population on coastal plains Poor construction of buildings due to low level of development within the region No early warning system Secondary Effects: Tourism affected in the region Coastal fisheries were affected and took time to recover Subsistence farmers and small businesses were wiped out Long-term Responses: The Indian Ocean Tsunami warning system was set up in June 2006 Tsunami response plans now in place in the region Managing tectonic hazards – prediction, protection & preparation It's not possible to prevent earthquakes and volcanic eruptions. However, careful management of these hazards can minimise the damage that they cause. Prediction is the most important aspect of this, as this gives people time to evacuate the area and make preparations for the event. Predicting and preparing for earthquakes Earthquakes are not as easy to predict as volcanic eruptions. Prediction Laser beams can be used to detect plate movement. A seismometer is used to pick up the vibrations in the Earth's crust. An increase in vibrations may indicate a possible earthquake. Radon gas escapes from cracks in the Earth's crust. Levels of radon gas can be monitored - a sudden increase may suggest an earthquake. The behaviour of wildlife can give clues Many of the prediction techniques used to monitor earthquakes are not 100% reliable. Planning and preparing for an earthquake is therefore very important. Preparation People living in earthquake zones need to know what they should do in the event of training people my involve holding earthquake drills and educating people via TV or radio. People may put together emergency kits and store them in their homes. An emergency kit may include first-aid items, blankets and tinned food. Protection Earthquake proof buildings have been constructed in many major cities, e.g. The Transamerica Pyramid in San Francisco. Buildings such as this are designed to absorb the energy of an earthquake and to withstand the movement of the Earth. Roads and bridges can also be designed to withstand the power of earthquakes.