Note: Chemical Nomenclature

SES4U

Note: Earthquakes

Elastic Rebound Theory:

Earth crust on either side of a fault move in

Rather than sliding smoothly past each other,

Therefore, as the two plates move past each other,

Eventually,

Focus:

Epicenter:

Seismology: the study of earthquake waves

Earthquakes are produced when waves radiate in all directions from the focus.

Types of waves:

1.Surface Waves:

2.Body Waves:

Waves traveling through

P-wave:

S-wave:

Seismometer:

Suspend a heavy mass and allow earth to move underneath:

Two ways to measure and describe the size:

1.Intensity:

A measure of

Modified Mercalli Scale - see text p.

Drawbacks:

2.Magnitude:

A measure of

Richter Scale:

Richter Scale examples:

1.quake A = 5.5;

quake B = 6.5

Quake B has ____ times higher amplitude.

Quake B has ____ times higher energy.

2. quake A = 5.5;

quake C = 7.5

Quake C has _____________ times higher amplitude.

Quake B has _____________ times higher energy.

Destruction Caused by Earthquakes

Urban damage due to ground shaking depends on:

Liquefaction:

–Saturated unconsolidated material suddenly turns into a mobile fluid

–Mudflows can be triggered

–Buildings can collapse

Landslides:

Fire:

Caused by

Tsunamis:

Earthquake Prediction

Short-Range predictions:

–No reliable technique has been developed!

Long-Range Forcasts:

Predict probability of earthquake over a time scale ___________________

–Based on studies of historical time intervals between quakes for a given region.

•Ex/ if Parkfield, CA experiences 1 quake every 30 years, and the last one occurred there 20 years ago, there is a high probability of a quake in the next ten years.

Earthquakes & Earth’s Interior