Earthquakes And Tsunamis

Question 1

Earthquakes

Answer 1

Caused by a build up and sudden release of tension at all plate boundaries

Question 2

Strength of earthquakes

Answer 2

Varies due to physical processes

Question 3

Crustal fracturing, surface fracturing, and buckling

Answer 3

Pressure released when plates jolt past each other sending out seismic waves along a fault line

Question 4

Focus

Answer 4

Place where the actual movements start, can be a single point or spread out along a large section of a fault line

Question 5

Crust and its effect on earthquakes

Answer 5

Has a degree of elasticity which allows it to recoil back and forth from the initial jolt
Shaking the ground

Question 6

Epicentre

Answer 6

The point on the earths surface where the earthquake is first felt, immediately above the focus

Question 7

Magnitude

Answer 7

Strength of an earthquake

Question 8

What affects the magnitude (2)

Answer 8

Type of plate margin, destructive = big earthquake, constructive = lower magnitude but more frequent
Depth of focus, deep focus (deeper than 300km) =higher magnitude, less damage as shockwaves are deeper, wadati-benioff zone maps the position of the deep focus earthquakes above the subduction zone at destructive plate boundaries
Strongest come from foci in the Wadati-Benioff Zone