Earthquakes

Austin T. Koeckeritz

6.1 Forces in the Earth’s Crust

Key Concepts1. How does stress in the crust change Earth’s surface?

2. Where are faults usually found, and why do they form?

3. What land formations result from the forces of plate movement?

The three types of stress1. Tension- The stretching of rock.2. Compression- The Compaction of rock (pushing together).3. Shearing- The slipping of masses of rock in opposite directions

The three types of faults.

1. Normal Faults-Rocks pulling apart 1. Tension- The stretching of rock.

2. Reverse Faults-Rocks pushing together 2. Compression-The Compaction of rock (pushing together).

3. Strike-Slip Faults-Rocks Slipping past each other 3. Shearing- The slipping of masses of rock.

fault lines (3)

1. Normal Faults- Rocks pulling apart 1. Tension- The stretching of rock.

2. Reverse Faults-Rocks pushing together 2. Compression- The Compaction of rock (pushing together).

Anticline with syncline visible at far right- USGS. Note the man standing before the formation, for scale. en.wikipedia.org/wiki/Anticline

Anticline - A fold in the rock that bends upward

Syncline - A fold in the rock that bends downward

Why do the hills show different color layers? The different layers were laid down during different times

folding (2:18)

Fault block mountain - When two normal faults cut through a block of rock.

fault block mountain (1:25)

The Colorado Plateau, which spans some 130,000 square miles, is actually made up of many plateaus. PHOTOGRAPH REPRODUCED BY PERMISSION OF THE CORBIS CORPORATION.

Plateau - A large area of flat land elevated high above sea-level.

6.2 Earthquakes and Seismic Waves

Key Concepts1. How does the energy from an earthquake travel through Earth?

2. What are the scales used to measure the stretch of an earthquake?

3. How do scientists locate the epicenter of an earthquake?

1. What type of fault is this and where is it located?Strike-slip fault found in alaska

2. What causes this type of fault to occur? Two plates slide past each other in different directions.

3. Define - Earthquake - Shaking and trembling due to the movement of rock.

4. Define - Focus - Area beneath the surface where the earthquake begins.

5. Define - epicenter -Point on the surface above the focus.

The three different types of seismic waves.

1. P Waves- Primary Waves

2. S Waves- Secondary Waves that causes the crust to vibrate from side-to-side to up-to-down.

3. Surface Waves- Combined P&S Waves. The ground surface rolls with a wavelike motion.

Seismic wave - Carry energy from an earthquake away with focus.

Seismic waves, magnitude and richter scale (3:20)

Measuring EarthquakesThe three ways earthquakes can be measured.1. Marcela Scale

2. Richter Scale- Scale is rated 1-10

3. Moment Magnitude Scale

The following website is has good information about earthquakes: http://earthquake.usgs.gov/learning/kids//

1. Which of the three scale is used most often for scientists? The Moment Magnitude Scale

How do scientists use waves to determine the location of an earthquake? Scientists measure the differences in arrival times of S&P waves. Scientist then draw the at least 3 circles using data from different seismographs.

1. X-Axis-Distance from epicenter Y-Axis- arrival time 2. 7.5 Minutes3. 4 minutes4. 2,000= 3.5 Min

Earthquakes 4.25