Earthquakes (2) Flashcards
What is a shockwave?
A force of energy that shakes the ground.
What is a fault?
A crack or weak point in The Earth’s crust.
True or false
Earth’s plates move evenly.
False, they move unevenly.
Explain how shock waves occur.
The Earth’s plates move unevenly. They move slowly and grind against each other creating shock waves, that vibrate through the earth’s crust. The shock waves cause the ground to shake.
Where is weakest place where the tectonic plates meet?
The Earth’s crust.
Explain how earthquakes occur?
- Convection currents in the magma cause pressure to build plate margins.
- Rocks in the crust are either pulled apart or together.
- Pressure and tension cause the rocks to plate margins to shudder and then to slip in a sudden movement.
- Sudden movements cause movement along lines of weakness in Earth’s crust called faults.
- Earthquakes happen along the fault.
What is a tsunami?
A large wave of water caused by an earthquake in the ocean’s crust.
What is a developing country?
Countries where people are poor and uneducated.
True or false
People who live close to plate margins are at risk of being effected by a powerful earthquake.
True
How do people who live in countries where there are many earthquakes prepare for the effects of an earthquake?
By making buildings strong and having very good emergency plans.
Why is being prepared for an earthquake good?
It reduces the damage earthquakes can cause. In countries where people are less prepared, more damage and deaths occur.
Why do developing countries like Mexico and Haiti suffer badly when an earthquake strikes?
- They are poor.
- Their governments don’t have enough money to deal with the effects of a big earthquake.
- They rely on help from other countries.
Why do developed countries not suffer as much?
- They are richer.
- Their governments build stronger buildings.
- Have rescue teams.
- Have doctors.
What is an impact?
Force or strong effect.
How can we reduce the impact of earthquakes?(5)
- Doctors,nurses and medical supplies as well as emergency food and water supplies.
- Well-Trained rescue teams.
- Warning systems that tell people an earthquake has struck or a tsunami is approaching.
- Emergency plans that cut of gas and electricity as soon an earthquake strikes.
- Good equipment to cope with earthquake damage, such as helicopters, diggers and cranes.
