Earthquakes Flashcards
What’s another name for powerful forces?
Stresses
What’s a break in the earths crust?
Fault
What are vibrations that travel through earths crust carrying energy?
Seismic waves
What are caused by movement of rock beneath the earths surface?
Earthquake
What are the three types of seismic waves?
- Primary or P wave
- Secondary or S wave
- Surface wave
What waves vibrate side to side, up and down and cannot go through liquids?
Secondary or S waves
What waves are slower than S & P waves, are at the surface and cause severe damage?
Surface waves
Which waves expand and compress earths crust like an accordion?
Primary or P waves
What is the point of stress where the rocks break?
Focus
What is the point on earths surface directly above the focus on earths surface?
Epicenter
How do geologists locate the epicenter of an earthquake?
They use seismic waves
In what order do the three types of seismic waves arrive at a seismograph ?
P waves, S waves and Surface wave
P, S, Surface
Which type of seismic wave produces the most severe ground movements ?
Surface waves
What’s the SLOWEST seismic waves that produce the most severe ground movements?
Surface waves
What is the point on the surface directly above where an earthquake occurs?
Epicenter
What records ground movements caused by seismic waves as they move through the earth ?
Seismograph
What is the point beneath Earths surface where rock under stress breaks and triggers an earthquake?
Focus
What is a measurement of earths strength?
Magnitude
What is a vibration that travels through earth carrying the energy released during an earthquake?
A seismic wave
What is the rating system that measures the energy released by an earthquake?
Moment Magnitude Scale
What does the moment the moment magnitude scale measure?
An earthquakes total energy
What is measured North and South from the equator?
Latitude
What is measured East and West from the Prime Meridian?
Longitude
Crust full movement is caused by______________ that build up over time?
Powerful forces
