Natural hazards and tectonic hazards

why people live in tectonically active areas- social

- dont know the risks

- family, friends live there

- sense of duty to protect the area

- evacuation plans help minimise the risk

why people live in tectonically active areas- economic

- don't want to leave jobs

- mineral potential- volcanic ash enriches and makes volcanic soil fertile, attracting famers

- geothermal energy- can make money

- government offered financial help in the case of a hazard

- tourism- can earn money

4 ways of minimising the risk of tectonic hazards

- planning

- protection

- prediction

- monitoring

ways planning can help reduce the risk of a tectonic hazard

- stockpiling resources

- emergency services training

- government planning evacuation routes

- earthquake drills

- educate people on what to do

- avoid future development occuring in at risk areas

how can protection help reduce the effects of an earthquake?

- for new buildings use reinforced concrete which absorbs energy from earthquakes making the building less likely to collapse

- strengthen existing buildings and bridges with steel frames to prevent collapsing

- add automatic shut off switches which turn off electricity suppliesand gas to reduce the chance of a fire

how can protection help reduce the effects of a volcanic eruption?

- make stronger buildings so that they can withstand the weight of volcanic ash and don't collapse

- trenches and barriers used to divert lava from settlements, but little success so far

how can monitoring help reduce the effects of a volcanic eruption?

monitor early signs like tiny earthquakes, the release of gas and a change in the shape of the volcano

how can monitoring help reduce the effects of an earthquake?

seismometers and lasers can be used in early warning systems

monitor the earth's movements

how can prediction help reduce the effects of a volcanic eruption?

closely monitor the volcano

how can prediction help reduce the effects of an earthquake?

not reliable- but monitor movements of tectonic plates

which boundaries do volcanoes form at?

constructive and destructive

how does a volcano form at a destructive boundary?

- As plates move closer together, the denser oceanic plate is subducted/moves down into the mantle of the continental plate

- It melts

- A pool of magma is formed which rises through cracks in the crust

- when it reaches the surface it erupts forming a volcano

how does a volcano form at a constructive boundary?

- Plates move further apart

- This creates a gap/mid ocean ridge

- magma rises up into the gap forming a volcano

how does an earthquake form at a destructive boundary?

- plates are moving towards each other

- tension builds as one plate gets stuck as it moves past the other plate

- eventually the plates jerk past each other, sending out shockwaves which spread out from the focus

- these vibrations are the earthquake

how does an earthquake form at a CONSTRUCTIVE boundary?

- plates are moving away from each other

- tension builds in cracks in one plate as it moves away from the other

- eventually the plates jerk away from each other, sending out shockwaves which spread out from the focus

- these vibrations are the earthquake

how does an earthquake form at a CONSERVATIVE boundary?

- plates are moving past each other

- tension builds as the plates get stuck when grinding past each other in opposite directions OR the same direction but at different speeds

- eventually, the plates jerk past each other, sending out shockwaves which spread out from the focus

- these vibrations are the earthquake.

what are geological hazards?

Caused by land and tectonic processes. E.g. volcanoes, earthquakes

what are meteorological hazards?

caused by weather and climate e.g tropical storms and extreme weather

examples of primary effects of natural disasters

- buildings destroyed

- injured/killed

-crops damaged, water supplies contaminated

- electricity cables damaged

examples of secondary effects of natural disasters

- other hazards like tsunamis

- aid and emergency vehicles cant get through blocked roads and bridges causing more deaths

- disease due to lack of sanitation and clean water

- food shortages due to damaged crops

- weakened economy due to damaged businesses

- unemployment

examples of immediate responses to natural disasters

- evacuate

- treat injured

- rescue people

- recover dead bodies to prevent disease spreading

- provide temporary supplies- gas and electricity

- provide food, drink and shelter for homeless

- foreign gov/charities send aid workers, supplies or donations

examples of secondary responses to natural disasters

- repair infrastructure

- rehouse people

- repair roads

- reconnect broken electricity, water, gas and communication connections

- improve forecasting, monitoring and evacuation plans

- improve building regulations

- boost economic recovery by promoting tourism