Earthquake Basics
What is the point on the Earth's surface directly above the focus of an earthquake?
Epicenter
What are the two main types of seismic waves?
P and S waves
What scale measures earthquake magnitude?
Richter scale
At this boundary, plates move apart, creating new crust and sometimes small earthquakes
Divergent boundary
Where did the biggest Earthquake occur and how big was it?
Chile (Valdivar) and 9.5
What causes most earthquakes?
What is the movement of tectonic plates?
Which seismic wave travels the fastest?
P waves
What does the Richter scale measure?
The amount of energy released
What is the name of the famous fault line in California?
San Andreas
How do scientists locate the epicenter of an earthquake?
Triangulation- by measuring the time difference between P-wave and S-wave arrivals at several seismic stations
What is the point inside the Earth where an earthquake begins?
The focus
Which wave can only travel through solids and not liquids?
S-waves
What type of instrument records seismic waves?
Seismograph/gram
What kind of boundary is known for earthquakes?
Transform boundary
What plate boundaries and environments create tsunamis?
Convergent boundaries and underwater earthquakes
Can earthquakes occur away from plate boundaries? Why or why not?
What seismic waves cause the most damage?
Surfaced waves
How much more energy is released with each whole number increase on the Richter scale?
31x
What type of plate boundary forms when two plates slide past each other?
Transform
Why do scientists use seismic waves to study the earths interior?
They allow us to "look inside" of Earth, we can see what the layers are made up of
What term describes a smaller earthquake that occurs after a larger one?
Aftershock
What is the difference in motion between P-waves and S-waves?
P waves are more compressed, S waves are slower and move side to side
What scale measures the intensity of an earthquake based on damage?
Modified Mercalli Scale
What is a fault?
A crack or fracture in the Earth’s crust along where movement has occurred
What is a lahar?
Volcanic mudflow