Earthquakes

Question 1

Displacement

Answer 1

The offset of segments or points that were once continuous or adjacent.

Question 2

Stick-slip

Answer 2

Movement starts, but quickly stops due to friction

Stress builds, causing failure

Question 3

Hypocenter vs. Epicenter

Answer 3

Hypocenter (or focus): The spot within the Earth where earthquake waves originate

Epicenter: Land surface above the hypocenter

Question 4

Seismicity

Answer 4

Motion along a newly formed fault

Motion on an existing fault

Question 5

*Body Waves

Answer 5

Primary (P) Waves: Compressional waves, (Push Pull) travels through solids, liquids, and gases

Secondary (S) Waves: Shear waves, (Shaking) travels through solids only

Question 6

Surface Waves

Answer 6

Travel along Earth’s surface

Love (L) waves – Move back and forth like a snake

Rayleigh (R) waves – Move like ripples on a pond

Question 7

Magnitude

Answer 7

The amount of energy released

Question 8

Shallow Earthquakes

Answer 8

0-60km subduction trace

Earthquakes are rare below 660 km (mantle is ductile)

Question 9

Intermediate & Deep Earthquakes

Answer 9

Intermediate and deep earthquakes occur along the subduction trace

Question 10

Soil Liquefaction

Answer 10

Waves liquefy H2O-filled sediments

High pore pressures force grains apart, reducing friction

Liquefied sediments flow as a slurry

Question 11

Tsunamis

Answer 11

Result when earthquakes change the seafloor (Not Tidal Waves)

Normal faulting drops seabed; reverse faulting raises it