Restless Earth

Restless Earth

1. Layers of the Earth

   • Crust is the Surface of the Earth
     • Lithosphere
       • Split into Tectonic Plates
     • Two Types
       • Oceanic
         • Basalt
         • Solid
         • Denser
         • Always new being formed
           • When magma from the mantle cools
           • As plates move appart
       • Continental
         • Granite
         • Solid
         • Less Dense
         • Older
   • Inside the Earth is Hot
     • Know this because...
       • Hot Springs
       • Molten Lava from Volcanos
       • Geysers
     • Radio Active Decay of elements
       • e.g. Uranium
     • Geothermal Heat
     • Plumes
       • Upwellings in molten rock through the asthenosphere
         • To lithosphere forming a...
           • Hot Spot

2. Pangea

   • All continents joined
     • Super Continent
     • Know this because...
       • Same fossils found in...
         • Africa and South America
   • Split because of plate Tectonics
     • 15 big ones
     • 20 small ones
     • Very Slowly...
   • 250 million years ago

3. Plate Boundaries

   • 3 Types
   • Conservative
     • 2 plates sliding past each other
       • Along a fault
     • No Volcanos
     • Lots of Earthquakes
       • Dsetructive
         • Up to 8.5 magnitude
       • Daily Tremmors
     • E.g. San Andres Fault
       • pacific and North American plates passing each other
   • Where Earthquakes and Volcanos usually occur
   • Consatructive
     • Two plate boundaries moving appart
       • Magma rises to fill the surface
         • can form a volcano
           • Don't erupt with much force
       • Earthquakes
         • Small
       • E.g. The mid Atlantic Ridge
         • In Iceland
         • Eurasian and North American plates pulling appart
   • Destructive
     • Continental and oceanic Plates colliding
       • Ocenaic plate is subducted under
         • Because it is denser
         • Starts to melt
           • Due to friction caused by movement
           • Is now melted hot, liquid, rock magma
             • Rises through the cracks in continental plate
     • E.g. Andres Mountains
       • In Chilie
       • Nazca Oceanic Plate is subducted under South American Continental Plate
     • Destructive Volcanos
       • 8.5 manitude
   • Collision Zone
     • Type of destructive Boundary
     • 2 of the same type of plate collide
       • Causes material between to buckle and rise
         • Forms fold mountains
     • E.g. Himalayas
       • Collision of African and Eurasian Plates
     • Destructive Earthquakes
     • Rare Volcanos

4. Mt St Helens

   • USA
     • Developped country
       • Can afford to spend money on..
         • monitering
         • protection
         • Evacuation
   • Destructive plate boundary
     • Pacific and North American plate boundary
   • lots of eruptions leading up to
   • Effects
     • Enviromental
       • 70 mm of ash
         • falls across ares
       • 2 million animals were killed
       • mudflows
         • Raised temperature of lakes and rivers
     • Economic
       • damage to crops
         • $175 million
       • Post office and other bussinesses
         • Shut down
           • In Cougar
   • Can be monitored and predicted
     • Can evacuate people
   • May 1980

5. Sichuan

   • Central China
   • May 2008
   • 8 magnitude
   • Social Impacts
     • 70 000 died
     • 375 000 people died
     • 5 million homeless
   • economic impacts
     • 1 million
       • job losses
     • re buliding
       • $75 billion
   • Lots of aftershocks
   • Caused landslides
   • Responses
     • Local
       • hard because of...
         • heavy rain
         • landslides
         • aftershocks
       • Prime minister flew in
       • Soliders were sent
       • People donated £1.5 billion
     • International
       • UK gave $2 million
       • Lots of countries sent supplies
         • Tents
       • Nearby countries flew in rescue teams
   • Future...
     • Sctrict building rules
     • can be doe in poorer areas
   • Developing

6. Earthquake!

   • Epicentre
     • Point on surface directly above where it started
   • Seismic Waves
     • Waves of energy which cause the ground to shake
   • Focus
     • point where earthquake starts

7. Japan

   • March 2011
   • Effects
     • Tsunami
       • caused more deaths than earthquake
         • were not as prepared
     • Social
       • 18000 deaths
       • Lots homeless
     • Economic
       • $360 billion in losses
     • Environmental
       • Radiation leaks
         • causes cancer
       • caused fires by damaged infrastructure
   • 9.0 magnitude
   • developped
     • were prepared for earthquake
       • Strict building regulations