WHEN THE EARTH SHAKES- THAT'S AN EARTHQUAKE

Elastic Rebound Theory

Stress from forces build up until it is suddenly released in the form of an Earthquake

What are the 2 kinds of Seismic Waves?

Body and Surface waves

What are the 2 kinds of Body Waves?

Primary (compressional) and Secondary (shear)

What are the 2 kinds of Surface Waves?

Raleigh (vertical displacements) and Love (shear)

Focus

Where the earthquake occured

Epicenter

The spot directly above the Earthquake

What kind of wave is the fastest?

Primary Waves

What kind of wave is the slowest?

Surface waves

What can waves help us with?

Determining the location and size of an Earthquake

What are the effects of Earthquakes

Tsunamis, world distribution of earthquakes, earthquakes and plate tectonics.

What kills people?

Buildings

What disaster is this?

Soil Liquefaction

What disaster is this?

Surface Displacement

What disaster is this?

Ground Rupture

What disaster is this?

Fence Compression

What disaster is this?

Buckled Concrete

What boundary is Rifting associated with

Divergent/Extensional

What boundary is Collisional associated with

Convergent/Compressional

What boundary is Shear associated with

Transform/Strike-slip

What are the 3 waves to measure Earthquakes?

Richter Magnitude Scale, Moment Magnitude Scale, and Modified Mercalli Intensity Scale

Richter Magnitude Scale

Log scale which has no upper bound. Small earthquakes may yield negative values. Tends to be inaccurate at >7 magnitudes

Moment Magnitude Scale

measurement of the amount of work done during the earthquake. Based on rock strength, area of rupture, and displacement during the event.

Modified Mercalli Intensity Scale

based on the damage associated with a particular event at a particular location. Ranges from I (less damage) to XII (more damage).

How is Seismicity along subduction zones?

Earthquakes are shallow, intermediate, and deep, but have systematic location.

What are earthquakes shallower than those along suduction zones?

Mid-ocean ridges