Geography Earthquakes Flashcards
What is an earthquake?
An earthquake is a sudden movement and shaking of the earth
How does an earthquake occur?
By the movement of the plates of the crust e.g when plate collide or slide past each other.
What happens when plates move?
The rock suddenly breaks and slips along a crack called a fault line
What is a fault line?
A crack in the earth
What’s a focus?
A focus is a point inside the earths crust where the earthquake starts
What is a epicentre?
An epicentre is directly above the focus on the earths surface. Most damage is done here.
What is a tremor?
A tremor is a shockwave coming out from the focus
What is an aftershock?
An aftershock is mini earthquakes after the main earthquake.
Where do earthquakes happen?
Pacific ring of fire, Himalayans and the mediterranean.
What measures the strength of an earthquake?
The Richter Scale
What is the definition of magmatude?
Magmatude means strength
What does 0_4 mean on the Ritcher scale?
It means very little damage is done.
What does 6.0 on the Ritcher scale mean?
It means major damage can be done
What does 7.0 and above on the Ritcher scale mean?
Major damage done over large area.
Where does the Ritcher scale go from
0_10
What were the impacts of Japan 2011?
Loss of life e.g 18,000 people lost their lives due to the Japan 2011 tsunami/earthquake and 130,000 buildings were destroyed.
Sample question- describe how an earthquake takes place
Most major earthquake happen at destructive plate boundaries. These two plates collide, and over decades pressure builds up at a point cs,led a fault line.When the pressure becomes to great,one plates slips releasing energy known as an earthquake. The point where the energy is realeased is called the focus. Energy radiates out in all directions, these waves are called shockwaves. Most damage is caused at the epicentre, which is the point on the rates surface directly above the focus, when an earthquake occurs under the ocean it can cause huge waves called a tusnami. E.g. Japan 2011 earthquake and tusnami
