Earthquakes Flashcards
20 questions;
What is an earthquake?
An earthquake is the sudden shaking/movement of the ground. They can be large or small and can happen basically anywhere.
Why do they occur?
What happens after they occur?
- They occur when a rock breaks beneath the surface of the earth. After it breaks, the pieces of the rock snap together and move along a fault.
What is a fault?
A crack in a body of rock.
What are seismic waves and what types of waves do they have?
Seismic waves:
Waves of energy that travel through earths surface, they cause the earth to crumble and shake during earthquakes.
Types of seismic waves:
- P- waves: (fastest wave)
- S- waves: secondary waves (wave occurs right after earthquake)
What are the 3 type of faults?
- Normal faults
- Reverse faults
- Strike- Slip Faults
What can an earthquake effect?
Tunnels, buildings, roads, and even gaslines.
What can occur if an earthquake happens on the ocean floor?
A tsunami.
How often do small magnitude earthquakes happen?
Every 10 seconds!
Where do most earthquakes occur?
They occur mostly near the boundaries of tectonic plates!
What are the different boundaries// what do they have?
- Divergent boundaries : pull apart; shallow earthquakes ; common along normal faults
- Convergent: plates collide; common along reverse faults
- Transform: shallow; happen along strike-slip-faults
True or false:
Older buildings tend to withstand the earthquakes better than newer
That is… False.
True or False:
There are more than one scale to measure an earthquakes magnitude.
True!
Fill blank:
The strength of an earthquake is caused by _____.
rocks
Fill blank:
________ are used to measure seismic waves and when the waves reach it, it produces a ________.
Seismometers are used to measure seismic waves and when the waves reach it, it produces a seismogram.
What are 2 other kinds of seismic waves?
Surface waves: Surface waves travel along the surface which causes more damage
Body waves: body waves travel through earths interior and move faster
