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The Restless Earth
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Describe the distribution of earthquakes around the world (3 marks)
The Crust So what is the pattern and why does it exist? Describe the distribution of earthquakes around the world (3 marks) Why do you think there are no earthquakes or volcanoes in the UK?
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It was caused by something called continental drift.
Did you know the land on earth used to be stuck together 225 million years ago!!! It was caused by something called continental drift. How was it proved that the continents were once clumped together like this?
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What are the differences between oceanic and continental plates?
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Past Question!
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Why do the plates move? Convection Currents
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What types of plate boundary are there?
Match the following images with their labels: Divergent/Constructive Transform/conservative Convergent/destructive Which one is missing?
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Past Question!
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How have ocean trenches formed?
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Add descriptions to each of these to explain fold mountain formation
Case Study: The Andes, South America How have fold mountains formed? How have people used them? Add descriptions to each of these to explain fold mountain formation
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Case Study: The Andes, South America How have fold mountains formed
Case Study: The Andes, South America How have fold mountains formed? How have people used them?
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Case Study: The Andes, South America How have fold mountains formed
Case Study: The Andes, South America How have fold mountains formed? How have people used them? 1. What is mined? What problems arise? 2. Why is HEP a good source of electricity? 4. Tourists go to see….. 3. What do people farm? How do they cope with the steep land?
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Earthquakes Volcanoes
Tectonic Hazards Earthquakes Volcanoes
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Types of Volcano Shield Volcano: Constructive Composite Volcano:
Draw a shield volcano and add labels. What plate boundary do we find them on? Shield Volcano: Constructive Composite Volcano: Destructive
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How have composite and shield volcanoes formed? Composite
These form on destructive plate margins and erupt violently and less often. Example Volcano: Mount Pinatubo, Philippines
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How have shield volcanoes formed?
Formed on constructive plate margins. These constantly erupt and have runny lava with little ash. Example Volcano: Skjaldbreiður, Iceland,
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Past Questions!
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What are the Characteristics of a Volcanic Eruption?
Tephra (pieces of debris)
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2. Lava Flows! Pahoehoe (Molten rock)
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3. Pyroclastic flow (hot gas and debris that travels down the side of the volcano)
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4. An Ash Cloud
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5. Lahars (Mudflow of pyroclastic material often mixed with melt water)
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6. Gases Water vapour Carbon dioxide Sulphur dioxide
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Can We Predict Volcanoes?
Can we reduce their impacts?
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Past Question!
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Why do people live near to them?
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What is a Super Volcano? A mega colossal volcano that erupts 1,000km³ of material Example: Yellowstone Caldera
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What would their impacts be?
Yellowstone erupted 2 million years ago and 1.3 million years ago. If it erupted again….. It would destroy 10,000 km2 of land Kill 87,000 people 15cm of ash over buildings within 1,000 km 1 in 3 people affected would die Ash would affect transport (planes, roads, water supply, farming) Lahars could occur 5 days later the UK would be affected Global climate could change from the insulating properties of the ash which would affect the jet stream for example, and ocean currents. Resulting in crops failing and people dying.
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Past Question!
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Case Study: A Volcanic Eruption and how it affects people Mount St Helens, Washington, USA
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After Before
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What are earthquakes? How do they happen? How are they measured?
Earthquakes happen when friction builds up between two plates and is then suddenly resealed
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Past Question!
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What is the difference between these two?
Which will cause buildings to collapse?
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The are measured on the Richter Scale on a Seismograph
How are EQs measured? The are measured on the Richter Scale on a Seismograph
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Seismograph after the Japanese Tsunami
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There are also foreshocks and aftershocks
There are also foreshocks and aftershocks. They may not be as high on the Richter scale but they can also cause damage.
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It is measured on a scale between I and XII.
Mercalli Scale This measures how much damage is caused by the earthquake based on observations. It is measured on a scale between I and XII.
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Get pupils to act this out and film it.
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Can we predict earthquakes?
Not precisely We know where plate boundaries are and this gives us some idea However, the UK had an earthquake in the Bristol channel this year and they can happen from cracks in oceanic or continental plates You can measure the amount of friction at the plate margin, however you cant tell exactly when the pressure may become too great. You can measure the amount of radon gas – more = an earthquake could happen, but this is unreliable. Animals can act differently before an earthquake – erratic pet behaviour or the mass movement of animals have been noted
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Case Studies: Comparison between and LEDC and MEDC Earthquake
Kobe, Japan (MEDC) Sichuan, China (LEDC)
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Case Studies: Comparison between and LEDC and MEDC Earthquake
Kobe, Japan (MEDC) Sichuan, China (LEDC) Collision Plate Boundary: Eurasian and Indo-Australian plate Destructive Plate Boundary
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Case Studies: Comparison between and LEDC and MEDC Earthquake
Kobe, Japan (MEDC) Sichuan, China (LEDC) Key facts: 2.28pm, 12th May on Richter scale. Lasted 120 seconds. $75 million damage done. Key facts: 5.46am, 17th Jan on Richter scale. Lasted 20 Seconds. $220 billion damage done Primary Effects: 69,000 dead 374,000 injured At lest 5 million injured 5 million buildings collapsed Several schools – one had 900 fatalities Communications ceased Roads blocked by landslides Primary Effects: 6,500 people died 40,000 seriously injured 300,000 homeless Gas mains ruptured Water pipes fractured Railway lines buckled 30% of Osaka and Kobe lines useable 2 million homes without electricity One million without water for 10 days Responses: Army troops deployed to help search and rescue effort via parachute as areas were cut off for up to 30 hours after the quake. Areas of land flattened for tent communities Tent production increased to help with 3.3 million required. 14th may china requested international help Japan, Russia and South Korea Red Cross had £100 million donations . Providing food, medicine and doctors in the camps for the homeless. 1 million temporary homes were built The governor of Sichuan hoped for recovery in 3 years. Chinas government pledged $10mill into the rebuild Banks wrote off debts by survivors so people could recover Secondary Effects: Fires from electricity and gas mains sparking People had to live in tents Economy suffered – Kobe port closed Responses: Railways 80%operational within a month Port was 80% operational a year later Sept 1996 the Hanshin express way was reopened.
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Past Question
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Past Question
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How can we reduce the impact of earthquakes?
Prediction Protection Preparation THE THREE P’s!!
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How can we reduce the impact of earthquakes?
2) Protection Earthquake proof buildings Spacing buildings out to reduce a “Domino” effect Having car parks on lower levels of multi-storey buildings so less people are killed if these levels collapse
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How can we reduce the impact of earthquakes?
3) Preparation Hospitals and Emergency Services plan to work together to ensure all areas of an area are covered Drills are also practised in schools etc. so people know what to do. Have designated “safe houses” so people know where to head in an emergency Have automatic shut offs of gas and electricity – reduces fire risk
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Preparation: An Earthquake Survival Kit Why are these in the kit?
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What is a Tsunami? How are they formed?
A tsunami (translated as “Harbour Wave”) is a wave where the ocean floor displaces the water above an earthquake. A tsunami can be 200km in length from crest to crest (100m normally) and travel at 800kmph. Waves heights out to see are however 1m high, normal waves are 2m, so they are not obvious. However when they reach land the front of the waves slows and the back catches up with it. Causing the “wall of water”.
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Case Study: Causes/effects and responses to a Tsunami: The Indian Ocean Tsunami 2004
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Case Study: Causes of a Tsunami: The Indian Ocean Tsunami 2004
Key Facts: Boxing Day 2004 9.1 on the Richter Scale 8.00am local time Sea floor moved up by 10M Case Study: Causes of a Tsunami: The Indian Ocean Tsunami 2004
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Before (top) and after of Banda Ache, near the epicentre of the earthquake.
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Primary Effects Tide went out a lot further than low tide, some locals saw this and ran, along with some tourists who had been taught this at school Within first hour, hit Indonesia at 8.15am – 166,000 dead, waves up to 20m high Within 2 hours, hits Sri Lanka, Thailand and Mainland India – 60,000 dead, waves reach 800kmph or 500kmph By the 5th hour – waves reach South Africa Total deaths – 230,000+ Millions homeless Caused drowning, flattening/removal of homes, towns, villages, transport links down
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Can we predict them? (Left)
Human Response New Indian Ocean Tsunami Warning System to detect waves (below) using satellites and monitors on ocean floor was put in place in Although they are expensive to maintain and put in for LEDCs near focus of EQ. Some tide gauges have been put in place as low cost alternative with a warning siren. $14million was given in relief aid worldwide Lots of media coverage as UK tourists were killed Secondary Effects Disease – malaria and cholera from the standing water which included dead bodies and sewer water Loss of tourism (and habitats) as coral reefs destroyed and tourists afraid to return Can we predict them? (Left)
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Past Question
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