Download Earthquake Summary Sheet

Earthquake Summary Sheet
1. earthquake: the release of tension (energy) built up from
the movement of plates along plate boundaries
2. fault: a break along the rocks where earthquakes occur
3. focus: place inside the Earth where the earthquake starts
4. epicenter: place on the Earth’s surface directly above the
focus
5. seismograph: instrument used to measure earthquakes
a. seismogram: a record of the earthquakes
6. seismic waves: waves created by the earthquake
a. types of seismic waves
i. primary waves (P waves):
1. first to arrive
2. fastest moving
3. causes materials to move back and forth
4. travels through solids, liquids, and gases
ii. secondary waves (S waves):
1. second to arrive
2. moves slower than P waves
3. causes materials to move side to side
4. travels through solids
iii. longitudinal waves (L waves):
1. surface waves
2. slowest moving waves
3. cause the surface to rise and fall like ocean
waves
4. cause the most damage
5. travels through solids, liquids, and gases
7. Types of faults
a. Normal fault: rocks pull apart (divergent boundary) and
one side of the fault will slide down the other  think of
it as “normal” to go down a sliding board
b. Reverse fault: rocks collide (convergent boundary) and
one side of the fault gets pushed up  think of it as the
“reverse” of going down a sliding board
c. Strike slip fault: rocks are sheared and slide past one
another (transform boundary)
8. Richter Scale: a scale to measure the energy released from
an earthquake
a. the higher the number, the stronger the earthquake
9. tsunami: large wave that can be a result of an earthquake
under the ocean floor
10. How to find the epicenter of an earthquake?
a. Scientists from at least 3 different seismograph stations
record the time it takes for the waves to reach that
seismograph. They calculate the radius of where the
earthquake could be. The location where the 3 circles
meet is the epicenter of an earthquake.
11. Earthquake Safety
a. What can you do to make your home earthquake safe?
i. Move all heavy object to lower shelves and the floor
ii. Make sure all gas, hot-water heater, and appliances
are secure
iii. Place sensors on your gas line to prevent fire
iv. Keep away from windows
v. Watch for fallen power lines
b. What can you do to make a building earthquake safe?
i. Use base isolators (rubber and steel supports) that
allow the building to move freely with the vibrations
of the earthquake
ii. Use bendable water and gas pipes