Geology: Earthquakes

Question 1

What is an earthquake?

Answer 1

A sudden release of energy due to movement along fault lines.

Question 2

What factors affect earthquake damage?

Answer 2

1. Soil type – Weak soils (peat, clay) amplify shockwaves.
2. Building resonance – Structures must avoid natural vibration frequencies.
3. Depth of earthquake – Shallow quakes cause more destruction.

Question 3

What is the equation for seismic motion?

Answer 3

F⋅cos(wt+ϕ)=m¨u+c˙u+ku

Where:

m = mass
c = damping coefficient
k = elastic modulus