Chapter 6 - Section 2 - Earthquakes and Seismic Waves Flashcards
How does energy from an earthquake reach Earth’s surface?
through seismic waves from the focus through Earth’s interior and across the surface
What kind of movement is caused by P waves?
compression and expansion
What kind of movement is caused by S Waves?
side to side and up and down
What kind of movement is caused by surface waves?
some roll like ocean waves
some shake side to side
When do P waves arrive at the surface in relation to S waves and surface waves?
P waves arrive first
S waves arrive second
What is an earthquake’s magnitude?
The measurement of an earthquake’s strength based on seismic waves and movement along faults.
What is the Richter scale?
A scale that rates an earthquake’s magnitude based on the size of its seismic waves.
What are the advantages of using the moment magnitude scale to measure an earthquake?
can be used to rate earthquakes of all size
What type of data do geologists use to locate an earthquake’s epicenter?
seismic waves
What is an earthquake?
The shaking that results from the movement of rock beneath Earth’s surface.
what is the focus?
The point beneath Earth’s surface where rock breaks under stress and causes an earthquake.
What is the epicenter?
The point on Earth’s surface directly above an earthquake’s focus.
What is the Mercalli scale?
A scale that rates earthquakes according to their intensity and how much damage they cause at a particular place.
What is magnitude?
The measurement of an earthquake’s strength based on seismic waves and movement along faults.
What is a seismograph?
A device that records ground movements caused by seismic waves as they move through Earth.
