geography - tectonic hazards

• what are natural hazards


  things like earthquakes that can cause damage to humans and property
• what are the four types of hazards

  1. atmospheric - hurricanes
  2. geomorphological - flooding
  3. biological - forest fires
  4. tectonics - earthquakes
• there are four layers of the earth. the outer one is the crust, the layer below is the mantle. finally there is the core which is split into the inner and outer core. what are the layers made out of?


  crust - rock

  mantle - liquid rock

  core - mixture of solid and liquid rock
• what affects hazard risk?

  population density, HIC/LIC, location, time of day
• which is denser the continental plate or oceanic plate?

  oceanic
• constructive margins do what?

  move apart, this causes hot magma to rise between plates and cool down to form solid rock, this often forms shield volcanoes
• destructive plate margins do what?

  an oceanic plate subducts under a continental plate which forms an ocean trench, friction causes oceanic plate to melt and the pressure forces magma up to form coomposite volcanoes.
• what is the convection theory?

  movements of liquid rock in the mantle cuases the plate tectonics above to move
• what is ridge push, slab pull?

  at constructive margins ocean ridges form beneath them, the mantle melts this, molten magma rises as plates move apart to form new material
• what is the difference between primary and secondary effects?

  primary effects happen immediatley during or after hazard because of the hazard, wheras secondary effects happen as a result of the primary effects
• where does an earthquake happen?

  at the focus, you feel it at the epicentre directly above it
• what plate tectonic has the most severe earthquakes?

  destructive because pressure builds and is then releases as an oceanic and tectonic plate push together
• describe the nepal earthquake.

  when - 2015

  where - Ghorka, Nepal

  richter scale - 7.9
• ddesccribe the italy earthquake.

  when - 2009

  where - L'Aquila, Italy

  richter scale -6.3
• what where the primary effects of the nepal earthquake

  1. 9000 people died and 20,000 injured (social)
  2. electricity and water supplies affected (social/econoomic)
  3. 7000 schools destroyed (social)
  4. 50% shops destroyed (economic/social)
• what where the secondary effects of the nepal earthquake?

  1. 3 million homeless
  2. avalanches on everst killed 19 people
  3. landslide blocked roads 140km from the capital causing further flooding
• what where the primary effects of the italy earthquake?

  1. 308 people died and 1500 injured (social)
  2. 10,000 - 15,000 buildings collapsed (social/economic)
• what where the secondary effect of the italy earthquake?

  1. 67,000 homeless
  2. aftershocks triggered landslides causing additional damage
  3. number of students at local university has decreased
• name the responses to the nepal earthquake

  1. search and response teams (short term)
  2. tents provided (short term)
  3. temporary pop-up hospitals (short term)
  4. food and bottled water sent (short term)
  5. roads repaired (long term)
  6. 7000+ schools rebuilt/ repaired (long term)
• name the responses to the italy earthquake

  1. hotels provided (short term)
  2. the british red cross raised £171,000 in support (short term)
  3. mortgages and bills for gas and electric were suspended (short term)
  4. residents didnt pay taxes in 2010 (long term)
  5. students were given free public transport for 3 years (long term)
• why do people live near volcanoes?

  geothermal energy - provides electricty and hot water

  farming - fertile soil

  mining - valuable minerals on volcanoes
• what is used to measure gas that escapes from volcanoes?

  radon detection devices
• how do lazers predict a volcanic eruption?

  they help see if the size or shape changes
• how do seismometers predict volcanic eruptions?

  they detect small earthquakes or rumbles of a volcano before it erupts