Unit 34 The Earth And Plate Tectonics

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Unit 34

The Earth and Plate Tectonics

The nature of the Earth’s crust.

That rocks contain different types of minerals which are formed by elements joining together.

That there are three rock types, sedimentary, igneous and metamorphic.

That fossils are only found in sedimentary rocks.

That the rock cycle is a continue process of rock formation and breakdown.

That the Earth’s crust is a collection of tectonic plates.

That these plates are in constant movement leading to subduction, uplift, faults and Earthquakes.

That where plates meets, features like mountain ranges, volcanoes and deep sea trenches are found.

How Earth’s atmosphere has changed over time.

The nature of Earth’s seismic activity.

The destruction caused by Earth's seismic activity and tectonic plate movements.

Rock, Cycle, Formation, Erosion, Breakdown, Sedimentary, Igneous, Metamorphic, Sediments, Minerals, Elements, Plates, Tectonics, Seismic, Waves, Earthquakes, Core, Crust, Mantle, Continents, Lithosphere, Asthenosphere, Mesosphere, Mountains, Volcanoes, Faults, Subduction & Uplift. Unit 34: The Earth and Plate Tectonics web: www.science-interactive.co.uk email: sales@science-interactive.co.uk Science Interactive LTD PO BOX 50764 LONDON NW6 9AT Click mouse to begin Science Interactive LTD Copyright 2005 Understand: Keywords:

The Earth’s crust The Earth’s crust ranges from 5 to 65 kilometres thick. About 25% of the Earth’s crust lies above the great oceans and seas. It is extremely important for human survival, with its top layer of nutrient rich soil , its minerals and metal ores. A m_______ is any solid substance that is rich in elements like iron, silicon and oxygen. Rocks are complex mixtures of minerals containing many different e_________, chemically joined together. The main elements in the Earth’s crust are oxygen, silicon, aluminium and iron. Name three metal ores found in the Earth’s crust ? Earth’s crust: Science Interactive LTD Copyright 2005 Word bank: mineral elements Fe AL Si O Symbol Mg K Na Ca Symbol Magnesium Potassium Sodium Calcium Element 2% 5% Iron 2.5% 8% Aluminium 3% 28% Silicon 47% Percentage Oxygen Element 3.5% Percentage Notes Diagram Earth The Earth’s surface

The rock cycle The rock cycle is a continual process of rock formation and breakdown. The three types of rocks: s____________, igneous and metamorphic are recycled in this way over many millions of years. The movement of the Earth’s plates, which is driven by the convection c_________ inside its mantle causes uplift and burying of all three types of rocks. At the plate boundaries, geographical features like mountains, volcanoes or trenches are formed. The rock cycle: Science Interactive LTD Copyright 2005 Word bank: sedimentary currents Uplift cooling continental crust Erosion Heat and pressure Heat and pressure Uplift Pressure Heat Magma Metamorphic Igneous Uplift Sedimentary Uplift The movement of the plates is driven by the convection currents deep inside the Earth's mantle. At plate boundaries mountains or trenches form due to the huge pressures involved. Inside the Earth

Formation of the Earth’s rocks one All three rocks types that make up the five continental plates are continually formed and broken down by chemical, p_________ and biological weathering. Their origins and how they are formed are very different giving them their own unique properties. Follow the diagrams and explanations below and learn the starting materials and how each type of rock is formed (sedimentary, igneous & metamorphic.) Rock formation: Sedimentary Igneous Metamorphic Science Interactive LTD Copyright 2005 Word bank: physical Formed rock Metamorphic rock forms when either igneous or sedimentary rock is buried. High temperatures and pressure cause the crystals to realign giving the new rock very different properties Igneous rock is formed when buried rock is heated forming magma. Molten magma rock rises to the Earth’s surface through cracks and then cools forming igneous rock. Any rock type that is eroded by chemical, physical and biological weathering can lead to the formation of sediments. These sediments begin to form layers which are then subjected to compacting over time. Notes Metamorphic Starting materials Rock Sedimentary Igneous

Uplift, Erosion, Sediments, Burial, Heating, Pressure, Time & Uplift Formation of the Earth’s rocks two Rock recycling is linked to the movement of the tectonic plates that cause the formation of deep sea trenches and mountains. Weathered rock fragments that form sedimentary rocks can be subducted (buried) deep inside the Earth’s c________. These rocks are then subjected to high pressure and temperature causing them to metamorphose into metamorphic rocks . These rocks may be b________ further causing them to melt forming magma. When magma rises to the surface and cools igneous rock is formed. Earth’s rock types: Science Interactive LTD Copyright 2005 Word bank: crust buried Sedimentary: Any rock type that is eroded by chemical, physical and biological weathering can lead to the formation of rock forming sediments. Igneous: Igneous rock is formed when buried rock is heated forming magma. Molten rock rises to the Earth’s surface through cracks which then cools forming igneous rock. Metamorphic: Metamorphic rock forms when either igneous or sedimentary rock is buried and subjected to high temperatures and pressure. Metamorphic Igneous Sedimentary The rock cycle

Inner core Outer core Mantle Crust Inside the Earth’s Core Inside the Earth, there are four main layers: The outer layer is called the c_________, which is between 5 and 65 Km thick. Five continents or tectonic plates float on the mantle, the next layer. The outer and inner core comprises mainly of i______ and nickel. The outer core is molten, whereas the inner core despite the high temperatures is solid because of the immense pressure. Inside the Earth: Science Interactive LTD Copyright 2005 Word bank: crust iron Inner core The inner cores is under extreme pressure and is solid. Outer core Outer core comprises mostly of molten iron and nickel. Mantle This layer supports the Earth’s continental plates. The mantle moves slowly in convection currents. Crust Solid, less dense rock with a thickness between 5 and 65 km. Part Notes

Structure of the Earth The lithosphere which is up to 100 km thick, includes the continental crust and the upper part of the m________ . This is the relatively cool and rigid part of the Earth’s structure. The Asthenosphere is the middle part of the mantle and has a consistency of hot plastic. The Mesosphere is the bottom part of the mantle, is higher in temperature than the lithosphere and is more rigid due to an increase in p__________. What supports life is the very top of the crust and its soil which contains all the minerals that our crops require. The Earth’s crust: Science Interactive LTD Copyright 2005 Word bank: mantle pressure Both temperature and pressure increase with depth through the Earth’s mantle to the outer and inner core. This is a simplified model of the Earth’s structure showing the mantle, inner and outer core. The mantle can be further divided up into the lithosphere, asthenosphere and mesosphere. The temperature and rigidity of the mantle increases with depth. Notes Diagram Temperature and pressure Structure of the Earth

Continental drift In 1915 Alfred Wegener suggested that Africa and South America were once joined. Over millions of years, the two continents have separated and drifted apart. Following Wegener’s work, the theory of ‘ plate tectonics ’ was formed. The Earth’s crust is made from huge p_______ that move slowly over time because of the convection currents present in the mantle layer. Fossils of similar animals were found in rocks from Africa and South America, how does this help prove Wegener’s theory of plate tectonics ? Movement of the Earth’s crust: Science Interactive LTD Copyright 2005 Word bank: plates The Americas continue to move west from Europe at a rate of 2.5 cm per year. In another 200 millions years, the World map will have change beyond all recognition. Pangea, the super-continent once had the land mass, now known as Africa connected to the land mass now known as South and North America. Notes Diagram Present day (2005 A.D) Pangea (220 million years B.C)

Active Earth Earth’s crust consists of five huge tectonic plates, which float on the liquid mantle below. The heat that causes rocks in the mantle to become l________, come from radioactive isotopes like Uranium 235 . Huge convection currents , constantly rising to the surface cause forces that move these five tectonic plates. At plate boundaries, plates either move a_______ or crash into one another. These huge forces cause features like Earthquakes, volcanoes, trenches and mountains. Mountain ranges like the Alps and the Pyrenees are built because of moving plates. Active Earth: Science Interactive LTD Copyright 2005 Word bank: liquid away The movement of the Earth’s tectonic plates is caused by events deep inside the Earth’s mantle. Rising magma causes the plates to move away or towards each other, albeit very slowly. At the boundaries, huge forces lead to Earthquakes, volcanoes, deep sea trenches or mountains. The Earth’s surface and its geography is shaped and reshaped over its history and future by these plate movements. Notes Diagram Earthquakes Volcanoes Trenches and ridges Mountains

Uplift, Erosion, Sediments, Burial, Heating, Pressure, Time, Earthquakes, Volcanoes, Mountains & Deep Sea Trenches Active Earth Plate boundaries Earth’s tectonic plates are like a huge jigsaw covering the globe. Along the plate boundaries are regions where v__________ are found. These arise because the thickness of the plates around their edge thins to a mere five kilometres. This allows rising hot magma to break through the crust forming volcanoes. The most studied plate boundary area is called the ‘ ring of fire ’ found in the middle of the Pacific ocean. Here, numerous volcanoes spew out lava forming new islands made from i_______ rock. This is how the Hawaiian islands were formed. Plate boundaries: ring of fire Science Interactive LTD Copyright 2005 Word bank: volcanoes iron The ring of fire defines the boundary of the Pacific plate. This area experiences volcanic and Earthquake activity. The west coast of America lies on the San Andreas fault which constantly poses an Earthquake threat to the inhabitants of San Francisco. Volcanic area including the ‘ring of fire’ Active Earth

Uplift, Erosion, Sediments, Burial, Heating, Pressure, Time, Earthquakes, Volcanoes, Mountains & Deep sea trenches Active Earth Volcanoes one Magma that rises and breaks through the surface cracks found along Earth’s plate b___________ is called l______. This cools, forming i__________ rock. Successive layers of igneous rock leads to the formation of volcanoes. In 1980, Mount St. Helens in America erupted throwing out many millions of tons of ash, lava and rock debris. The eruption could be heard many hundreds of kilometres away. Scientists have yet to discover an accurate way of predicting when volcanoes may erupt. Until then, those whose choose to live close to volcanoes remain at risk. Volcanoes and their formation: Science Interactive LTD Copyright 2005 Word bank: boundaries lava igneous Volcanoes arise when molten magma forces its way through the cracks in the Earth’s crust. Hot magma rises to the surface as lava which then cools and forms igneous rock. Living near volcanoes is dangerous, scientists have yet to discover an accurate way of predicting when volcanoes may erupt. Until then, those whose choose to live close to volcanoes remain at risk. Formation of volcanoes Active Earth

Uplift, Erosion, Sediments, Burial, Heating, Pressure, Time, Earthquakes, Volcanoes, Mountains & Deep Sea Trenches Active Earth Volcanoes two Humans have lived in the shadow of volcanoes for many thousands of years. Why...because, the soils around volcanoes are extremely fertile due to many layers of n_________ rich volcanic ash falling over time. Volcanoes which erupt, throwing out their plug and millions of tonnes of hot debris are the most dangerous and unpredictable. Mount Vesuvius in Italy has and will continue to kill the inhabitants of Naples. Over the last 200 years, it has e_________ every two to five decades. It last erupted in 1944. When the next one will be and how many people will die no one can tell ! Types of volcanoes: Science Interactive LTD Copyright 2005 Word bank: nutrient erupted Shown left is a typical volcano. Notice the different layers of igneous rock as a result of separate eruptions and flows of lava. A steep-sided volcano is formed when thick lava flows from the volcano vent. This type of volcano can erupt violently because the vent can become blocked with cooled lava. A shallow-sided volcano is formed when think fast flowing lava flows from the vent. The base of these type of volcanoes can be over 200 km wide. Shallow sided volcanoes Steep sided volcanoes Active Earth

Active Earth Changing atmosphere one The Earth’s atmosphere is approximately 350 kilometres high, containing a mixture of gases which are trapped by Earth’s gravitational pull. The atmosphere contains two main gases: nitrogen and o________ and small amounts of other gases including carbon dioxide, argon and neon. The atmosphere also contains varying amounts of w_______ vapour. Our atmosphere provides us with the oxygen we need and protects us against ultra violet light. It also insulates our planet. The atmosphere has been almost the same as it is today for the last 300 million years. Our atmosphere: Nitrogen: Oxygen: Carbon dioxide Water Vapour: Average temperature: Inert gases: 79% 20% 0-100% 18 o C 0.97% 0.03% Science Interactive LTD Copyright 2005 Word bank: oxygen water Levels of carbon dioxide and other polluting gases (nitrous oxides and sulphuric acid) are rising. These gases are formed when fossil fuels like coal, gas and oil are combusted with oxygen. Ozone has also been lost because of the use of aerosol gases like CFCs. Our current atmosphere Earth’s atmosphere

Active Earth Changing atmosphere two The Earth’s atmosphere consists of five distinct layers stretching up to 350 kilometres above the Earth’s surface. Beyond approximately 10 kilometres (height of Everest) there is insufficient oxygen to support human life for long periods of time. The Earth’s atmosphere provides us with oxygen for respiration and contains o________ which protects us against UV radiation from the Sun. It also contains over 750 billion tonnes of carbon dioxide which is the raw material for p____________. This gas also traps the thermal radiation energy from the Sun. What other chemicals from human activity are found in the atmosphere ? Our atmosphere: Science Interactive LTD Copyright 2005 Word bank: oxygen photosynthesis Five distinct layers: Ionosphere, Mesosphere, Ozone layer, Stratosphere, & Troposphere. Our current atmosphere Earth’s atmosphere

Active Earth Changing atmosphere three The Earth’s atmosphere was created about 4.5 billion years ago and was very different to our current atmosphere. Then it was a very hostile environment. Over the last 4.5 billions years, it has changed because of volcanic activity and p_______ life. Even Human activity has changed our atmosphere over the last hundred years. Our current atmosphere insulates us, provides us with o_________ and protects us against harmful UV radiation. Our changing atmosphere: Science Interactive LTD Copyright 2005 Word bank: plant oxygen 2005 AD 2 billions years ago 2.5 billion years ago 4.5 billion years ago

Active Earth Changing atmosphere four The Earth’s atmosphere about 4.5 billion years ago was very different, even hostile to life, providing no oxygen for respiration or protection against harmful UV radiation. When Earth’s surface began to c_______, a new atmosphere was formed from the hot gases spewed out by the many thousands of active volcanoes. These gases included carbon dioxide, m_________, water vapour, ammonia and sulphur dioxide. How would the presence of sulphur dioxide affect the pH of the rain ? Our changing atmosphere: Science Interactive LTD Copyright 2005 Word bank: cool methane Atmosphere High volcanic activity Earth's atmosphere 4.5 billion years ago: Gases included; carbon dioxide, methane, water vapour, ammonia and sulphur dioxide. Average temperature 70 o C. Earth's atmosphere 4.5 billion years ago Atmospheric facts: The first atmosphere contained mainly carbon dioxide gas with average temperature of 70 o C. 4.5 billion years ago

Active Earth Changing atmosphere five The Earth’s atmosphere about 2.5 billion years ago had already began to cool enough for water vapour to condense forming the r_________, lakes and oceans. The presence of water would allow the beginning of life, some 500 millions years later. The main gas in the atmosphere was carbon dioxide. The average temperature would have been higher than today's values. Explain why the presence of water is considered essential for life to begin ? Our changing atmosphere: Science Interactive LTD Copyright 2005 Word bank: rivers Atmosphere Earth's atmosphere 2.5 billion years ago: Gases included; carbon dioxide, water vapour, nitrogen and sulphur dioxide. Average temperature 45 o C. Atmospheric facts: During this period, sulphuric acid from erupting volcanoes lowered the pH of rain causing acid rain. Medium volcanic activity Earth's atmosphere 2.5 billion years ago 2.5 billion years ago

Active Earth Changing atmosphere six About 2 billion years ago, plants began to manufacture oxygen as a by product of photosynthesis. Slowly, atmospheric carbon dioxide was used by p_______ and assimilated into their biomass. As carbon dioxide levels began to reduce oxygen levels in the atmosphere and oceans increased Increasing oxygen in the upper stratosphere led to the beginning of the formation of the o_______ layer which reduced cancer causing UV radiation. This would allow the evolution of new species able to use oxygen and plant glucose during cellular respiration. Our changing atmosphere: Science Interactive LTD Copyright 2005 Word bank: plants oxygen Atmosphere Earth's atmosphere 2.0 billion years ago: Gases included carbon dioxide, water vapour and nitrogen. Average temperature 35 o C. Atmospheric facts: The ammonia present in the early atmosphere has been changed to nitrogen. Plants began producing oxygen. Low volcanic activity Earth's atmosphere 2.0 billion years ago 2.0 billion years ago

Active Earth Changing atmosphere seven Over the last billion years, oxygen levels have increased because of plant photosynthesis. Animals use oxygen to respire glucose inside their cells. The ozone layer has now been established. Carbon dioxide levels have fallen to a very low 0.03% or 750 billion tonnes. Carbon has been removed by plants and animals and safely trapped underground in the form of c_______, gas and oil. Burning these f_________ fuels is adding 3 billion tonnes of carbon dioxide to the Earth's atmosphere every year causing global warming. What effects will global warming have on the planet over the next fifty years ? Our changing atmosphere: Science Interactive LTD Copyright 2005 Word bank: coal fossil Atmosphere Levels of carbon dioxide and other polluting gases (nitrous oxides and sulphuric acid) are rising. These gases are formed when fossil fuels like coal, gas and oil are combusted with oxygen. Ozone has also been lost because of the use of aerosol gases like CFCs. If unstopped, the greenhouse effect and the destruction of the ozone layer will lead to greater hardship for all of us. Very low volcanic activity Earth's atmosphere 2005AD 2005 AD

Causing the greenhouse effect Our atmosphere is changing and will continue to change for many years to come. The average concentration of carbon dioxide in the air is increasing because of human activities. Fossil fuels rich in c________ are extracted deep underground and combusted with o__________ forming over 3 billions tonnes of carbon dioxide per year. We are also destroying large areas of ancient forests in Africa and South America. Why does this affect carbon dioxide concentrations in the atmosphere ? Factors affecting atmospheric carbon concentrations: Science Interactive LTD Copyright 2005 Word bank: carbon oxygen Over 500 million cars are responsible for the release of carbon dioxide found in the atmosphere. Is public transport the answer ? Combustion engine Using renewable forms of energy liked wind power could reduce carbon levels and slow the greenhouse effect. The destruction of the rain forests adds to the carbon dioxide in the atmosphere and also increases the erosion of soil. Combusting fossil fuels like petrol, gas and diesel release over 3 billion tonnes of carbon dioxide every year. Notes Diagram Fossil fuels Deforestation Renewable energy

Over the last century, our use of fossil fuels has released huge amounts of carbon dioxide into our atmosphere. This has disrupted the b_________ between carbon in the form of carbon dioxide and carbon found tied up under rock in crude oil, natural gas and coal. Currently we are adding an extra 3 billion tonnes of carbon each year into the atmosphere. The carbon dioxide molecule traps infra red h_____ from the sun. Slowly our planet is warming because of the rising carbon dioxide levels. How can you reduce your dependence on fossil fuels like petrol and natural gas ? The greenhouse effect: The greenhouse effect Science Interactive LTD Copyright 2005 Word bank: balance heat Altitude (km) 15 50 Solar radiation Radiated out to space Absorbed in atmosphere by greenhouse gases Altitude (km) Solar radiation Radiated out to space Absorbed in atmosphere by greenhouse gases 15 50 Carbon dioxides traps heat energy from the sun. The amount of carbon in the atmosphere is increasing by 3 billion tonnes a year. The greenhouse effect The World’s energy demand and the use of crude oil is increasing. China in the next two decades will use more than the USA. World’s crude oil use There are over 500 million cars, all pumping out carbon dioxide from the combustion of octane or petrol. Car use is set to double over 20 years. Rising levels of carbon dioxide

Soil There is 3300 billion tonnes of carbon trapped in oil, coal and natural gas deposits found under rock sediments. The carbon cycle All living organisms require the element c_________ to make carbohydrates, proteins and other important molecules which make up living organisms. Cellular respiration and decomposition by bacteria release carbon dioxide into the atmosphere. Plants use this during p_____________ at the same rate. The amount of carbon dioxide in the atmosphere should stay the same, but it is increasing rapidly because of the use of fossil fuels and deforestation . The carbon cycle: Ocean There is 1020 billion tonnes of carbon trapped in living organisms like algae. CO 2 is also dissolved in the oceans. Respiration CO 2 Atmosphere There is 750 billion tonnes of CO 2 trapped in the atmosphere. This is rising by 3 billion tonnes a year because of fossil fuel use and deforestation. Atmosphere Plant biomass Photosynthesis Land deforestation Buried fossil fuels Fossil fuel combustion Marine biomass Science Interactive LTD Copyright 2005 Word bank: carbon photosynthesis

Effects of global warming one Scientists have many theories as to what may happen over the next century because of rising carbon dioxide levels in the a__________, as a result of combusting fossil fossils and the subsequent rising global temperatures. There is now increasing agreement amongst scientists that atmospheric carbon dioxide levels need to be controlled. Many countries have signed ‘ The Kyoto Agreement ’ which aims to reduce carbon emissions over the next 20 years. This will perhaps s____ global warming. Only one country, America has not signed up, she is the biggest carbon polluter. Why do you think that America has not signed up ? Effects of global warming: Science Interactive LTD Copyright 2005 Word bank: atmosphere slow Flooding will increase over the next decade. In England (summer 2004), we had some of the worst flash floods on record, including Boscastle. Flooding The destruction of the Ozone by CFCs from aerosols will also add to global warming by reflecting less infra red heat given out by the sun. Ozone layer Notes Diagram Average world or global temperatures are set to increase by between 0.5 and 1 o C per decade for the next fifty years. Global warming More extremes of temperatures are now expected with lower rainfall in areas which already see little rain over the year. Drought

Effects of global warming two The greenhouse effect is a natural process where the 750 billions tonnes of c________ dioxide in the atmosphere maintains the Earth’s atmosphere at hospitable temperatures, which are supportive of life, here on Earth. Combusting fossil fuels is adding to this ‘warming effect’ causing average global t___________ to rise over the last fifty years. Global warming will continue, whilst we continue to combust fossil fuels like coal and oil. The World’s weather, habitats and temperature are set to change over the next century. Effects of global warming: Science Interactive LTD Copyright 2005 Word bank: carbon temperatures The ice caps have shrunk in size over the last 30 years. This may rise sea levels and also reduce the amount of the Sun’s infra red heat reflected back into space. Melting ice caps Animals and plants may undergo mass extinction in the next one hundred years if global warming continues. The Malarial Mosquito is spreading north into Europe. Biodiversity Notes Diagram The World’s weather will become more dynamic. In summer 2004, Florida in America was hit by three hurricanes causing immense damage. Weather Damage due to strong tides and wave action along the coast will also increase over the next decade. Parts of the England's coastline are now being eroded. Waves

Uplift, Erosion, Sediments, Burial, Heating, Pressure, Time, Earthquakes, Volcanoes, Mountains & Deep Sea Trenches Active Earth Building mountains Where continental plates move towards each other, a two step process occurs: Subduction : The very dense oceanic plate moves b_______ the less dense granitic plate. The resulting friction causes the rock to melt, forming volcanoes as well as leading to Earthquakes. Mountain building: The very dense oceanic part is totally subducted. The two plates then c________ folding the less dense granitic plate upwards, forming mountain ranges. The Andes in South America and the Himalayas were formed in this way. What feature might form if the two plates move away from one another ? Colliding plates: Plate 1 Plate 2 Science Interactive LTD Copyright 2005 Word bank: below collide Plate 1 moves under plate 2 slipping below the mantle. Mountains are formed when the two plates collide. Friction and heat causes plate 1 to melt forming new magma which then rises to the surface. The Andes and the Himalayas mountains are the result of plates moving towards each other at the rate of only 2 cm per year. Andes mountains Plates moving together Active Earth

Uplift, Erosion, Sediments, Burial, Heating, Pressure, Time, Earthquakes, Volcanoes, Mountains & Deep Sea Trenches Active Earth Ocean ridges and trenches Where continental plates drift apart from each other, magma rises through the fault, cools and forms a ridge. This usually occurs under the great o________ with the best example being the mid-Atlantic ridge . If there is sufficient material, new islands can appear above the level of the sea’s surface. Interestingly, the movement of the two p_______ (North American and Eurasian plate) means that America moves about two and half centimetres away from Britain every year. Calculate the distance moved over 10,000 years ? Separating plates: Plate 1 Plate 2 Science Interactive LTD Copyright 2005 Word bank: oceans plates The new material found in the ridge contains a high percentage of iron compounds, the cooled products of the Earth’s magma. The mid-Atlantic ridge between Europe and America runs north to south under the Atlantic ocean. Around the ring of fire many new islands including Hawaii have been formed. Atlantic ridge Plates moving apart Active Earth

Uplift, Erosion, Sediments, Burial, Heating, Pressure, Time, Earthquakes, Volcanoes, Mountains & Deep Sea Trenches Active Earth Earthquakes and Tsunamis Earthquakes occur around the World, close to the tectonic plate boundaries. An Earthquake is a sudden release of the f_______ that build up due to the movement of two plates against one another. In the last one hundred years, over a million people have died due to the destruction cause by the Earth shaking violently during an Earthquake. On December 26 th 2004 , a massive Earthquake underneath the sea, caused a massive tidal wave or T________ that killed over 250,000 people in Indonesia, Thailand and India. Plate boundaries: Science Interactive LTD Copyright 2005 Word bank: forces tsunami Moving plates can lead to compression, tensional and shearing forces. The continental plates found either side of the San Andreas fault have moved over 3 meters over the last 25 years. Work out the movement in centimetres of the two plates each decade ? Shearing Tensional Compression Active Earth

Uplift, Erosion, Sediments, Burial, Heating, Pressure, Time, Earthquakes, Volcanoes, Mountains & Deep Sea Trenches Active Earth Tsunami 26.04.2004 On December 26 th 2004 , a massive Earthquake underneath the India Ocean close to the coastline of Indonesia caused a massive tidal wave or Tsunami that killed over 250,000 people from Indonesia, Thailand, India & Sri Lanka. The majority of dead, lived in the Indonesian capital Bande Aceh. The millions of tonnes of w______ deposited in one great wave, swept away villages, towns and whole communities. The region today remains devastated and will take many decade to recover. Could an early warning system have saved lives ? Earthquakes and Tsunamis: Science Interactive LTD Copyright 2005 Word bank: water Tsunamis are caused when the seabed suddenly moves causing a column of water to be displaced. This then spreads from the centre like ripples in a pond. Huge volumes of water are eventually washed upon the shore causing massive devastation and loss of life. Earthquakes causing tsunamis Tsunami (26.12.2004)

Uplift, Erosion, Sediments, Burial, Heating, Pressure, Time, Earthquakes, Volcanoes, Mountains & Deep Sea Trenches Active Earth Seismic waves one The great forces involved when continental plates move towards or away from one another can cause Earthquakes. During an Earthquake, the energy of the moving plates is spread across the g______ in seismic waves. These waves travel through the Earth from a point of o______ or epicentre. There are three kinds of seismic waves; Primary , secondary and longitudinal waves . Although the way they travel through Earth’s layers is different, they all transfer energy from the Earthquake’s epicentre. Seismic waves: P waves S waves Longitudinal waves Science Interactive LTD Copyright 2005 Word bank: globe origin P waves (“push-pull”) travel through liquid as well as solid rock. Therefore they are able to travel through the inner core. S waves (“shakes”) travel more slowly than P waves and only through rock solids. These waves travel only through the mantle. Longitudinal waves travel through the Earth’s crust close to the surface and cause the majority of damage seen during Earthquakes. P Waves (primary) S Waves (secondary) and Longitudinal Waves Earthquakes and epicentres

Uplift, Erosion, Sediments, Burial, Heating, Pressure, Time, Earthquakes, Volcanoes, Mountains & Deep Sea Trenches Active Earth Seismic waves two Longitudinal waves travel through and are restricted to the solid crust. These waves also cause most of the damage seen on the crust’s surface. The P (primary) and S (secondary) waves both travel through the Earth, but they behave very differently. From data collected by s________ all over the World, primary (P) waves travel through the core as well as the Earth’s mantle. At stations X and Z, no secondary (S) waves are received. This data tells us that S waves cannot travel through the liquid core. Also, this information has given us the diameter of the core, which is about 7000 km. Seismic waves: Earthquake Station X Station Y Science Interactive LTD Copyright 2005 Word bank: stations P waves travel through liquid as well as solid rock. Therefore they are able to travel through the inner core. S waves travel more slowly than P waves and only through solids. These waves travel through the mantle only. Longitudinal waves travel through the Earth’s crust close to the surface. P Waves (primary) S Waves (secondary) and Longitudinal Waves Waves through the Earth’s crust

Uplift, Erosion, Sediments, Burial, Heating, Pressure, Time, Earthquakes, Volcanoes, Mountains & Deep Sea Trenches Active Earth Seismic waves three Where you find Earthquake regions, you will always find scientists monitoring seismic activity and the movement of the tectonic plates. Seismic activity (S, P & L waves) can be monitored and recorded using a seismograph. This instrument is s_________ to movements caused by S, P and L waves travelling through the Earth’s crust. Around the World, there is a huge network of seismographs that allows us, to better understand and perhaps one day p_________ Earthquakes. Two such places include where the Pacific plate meets the Eurasian plate forming the Japan trench, and where the South American plate meets the Nazca plate forming the Peruvian-Chilean Andes. Seismic waves: Science Interactive LTD Copyright 2005 Word bank: sensitive predict Distance from epicentre (km) 0 2000 4000 6000 S wave P wave 30 15 0 Time (min) Time (min) P waves travel through liquid as well as solid rock. Therefore they are able to travel through the inner core. S waves travel more slowly than P waves and only through solids. These waves travel through the mantle only. Longitudinal waves travel through the Earth’s crust close to the surface. P Waves (primary) S Waves (secondary) and Longitudinal Waves Seismographs

Uplift, Erosion, Sediments, Burial, Heating, Pressure, Time, Earthquakes, Volcanoes, Mountains & Deep Sea Trenches Active Earth Earthquake damage The great forces involved when continental plates move can cause Earthquakes along the boundaries, where tectonic p________ meet. Friction builds and builds between the moving plates. Eventually the plates overcome the friction and s______ suddenly. The focus of the Earthquake is deep underground, with the epicentre directly above the surface. The vibrations of the Earth’s crust can lead to widespread damage of buildings and other structures. Building failure can lead to massive lose of Human life. Earthquake damage: Earthquake Science Interactive LTD Copyright 2005 Word bank: plates slip The San Andreas fault runs from Seattle through Los Angeles down to Mexico. This is where the Pacific and North America plates collide. This could be the location of the next big earthquake. In late 2005, an Earthquake struck the border region of Pakistan killing up to 50,000 people and making many more homeless. The relief effort continues to this day. In 2004, an Earthquake and subsequent tsunami killed over 250,000 in Indonesia, India and the surrounding areas. In some areas, entire villages and towns were destroyed and their inhabitants killed. Who is next ? Pakistan 09.10.2005 Indonesia 26.12.2004 Waves causing destruction

1: Define the following terms: Sedimentary, Igneous, Metamorphic, Minerals, Earthquakes, Faults, Subduction, & Uplift. 2: Look at the diagram of the three types of Rocks. Complete the table: 3: Using the rock cycle, describe the steps required to turn: a) Igneous rock into sedimentary rock. b) Igneous rock into metamorphic rock. c) Sediments into sedimentary rock. 4: A sample of limestone can be distinguished from a sample of sandstone by adding dilute acid. No reaction takes place with the sandstone. Describe what you would see with limestone and give a word equation for the reaction. 5: Why would you expect to find the same fossils in rocks from South America and Africa. Extension questions and homework Sedimentary Igneous Metamorphic Science Interactive LTD Copyright 2005 How are they formed Metamorphic Igneous Sedimentary What are there properties Examples Rock

6: Complete the table: 7: Describe how: a) Frost damage can weather rocks. b) Rapid changes in daily temperature can weather rocks. c) Rain water can become acidic. d) Valleys and are formed by rivers over millions of years. e) Moving water can erode rocks over time. 8: Complete the following: As weathered pieces of rock are transported by gravity, _________ or water they can wear away more rock. This process is called ___________. Sedimentary rock is formed when ____________ in a river are deposited in lakes or ________. Igneous rock forms when _________ lava cools. Metamorphic rock is formed when either ______________ or ______________ is subjected to heat and ___________ over time. 9: Answer the following questions: a) Describe the life cycle of the Earth’s tectonic plates from 200 millions years BC to present day. b) What drives the movement of the five tectonic plates. c) What four events happen around the boundaries of the tectonic plates. Science Interactive LTD Copyright 2005 Diagram ___________________ ? Chemical ___________________ ? ___________________ ? Caused by ? Biological Physical Type of weathering

10: Look at the information in the table below. It shows the years of eruption, the time since the previous eruption and the number of millions of tons of lava erupted: a) Predict when Vesuvius will next erupt. b) Find out why people live in volcanic regions or on their slopes. c) If Vesuvius erupted this year, work out how many millions of tons of lava would be thrown out. 11: a) Describe how mountains like the Andes are formed. b) How is a deep sea trench like the ‘Mid Atlantic Ridge’ formed. c) What is the difference between S and P seismic waves. d) What piece of equipment do scientists use to monitor and record Earthquakes. Describe how they work. 12: Name the mountains formed by the following plate movements: a) The Indian and Eurasian plate moving together b) The African and Eurasian plate moving together. c) The Pacific and South American plate moving together. d) What can be found between the Pacific and Indian plate. Internet: Go to google.co.uk and find about the last eruption of Mount St. Helens in the USA. Also find out about the ‘ring of fire’ and the formation of the Hawaiian Islands. Furthermore find out about the tsunami that struck Indonesia and other countries on 26 th of December 2004. Science Interactive LTD Copyright 2005 ____ ? 25 12 80 19 119 27 Millions of tons erupted 64 1858 34 1906 15 1944 23 1929 ____ ? 14 34 Years since previous eruption 20__ ? 1872 1794 Year of eruption