BY: Real Daisy
What is an Earthquake?
Earthquakes are vibrations of the
Shaking of Earth's crust a forceful
trembling of the Earth's crust that
causes damage to edifices.
They are also
called, quake, tremor, temblor.
What Causes an Earthquake?
Earthquakes are outcomes of the rapid release
of tectonic pressure through the fault line or
When the earth releases energy in the earth’s
crust, it creates seismic waves, which causes
An earthquake is a great shaking of Earth's
surface. It is caused by the cracking and
shifting of the platesis of rock that make up the
planet's layered crust
P & S WAVES
There are different kinds of seismic waves, &
they all move in different ways. The 2 main
kinds of waves are ‘body waves’ and ‘surface
P & S waves are considered ‘body waves’
Earthquakes create several kinds of seismic
waves including P, for "Primary" and S, for
For a better understanding you can visit:this
website with visual representations
A P wave, or compressional wave, is a seismic
body wave that shakes the floor back and forth
like a coil
P waves are the fastest kind of seismic
wave, and therefore, the first to be recorded on
P waves can move through solid rock and
fluids,(like water or the liquid layers of the
earth). It pushes and pulls the rock it moves
through; just like sound waves can push and
pull the air
An S wave, or shear wave, is a seismic body
wave that shakes the ground back and forth
(perpendicular) to the direction the wave is
The second wave you feel in an earthquake is
called an S wave .
S waves are much more slower than P waves.
They can only go through a solid , not through
S waves move in a more shear motion
Largest Earthquakes in
Fort Tejon, California: Magnitude 7.9:
San Francisco, California : Magnitude 7.8 :
Imperial Valley, California : Magnitude 7.8 :
Owens Valley, California : Magnitude 7.4 :
Landers, California : Magnitude 7.3 :
After a large earthquake occurs, there is still a
danger and possibility of an after shock hitting.
After Shock: a smaller earthquake, sometimes
one of many, that follow a large scale
After Shocks occur because even though the
tension with the 2 plates is released, their
edges need to adjust to new positions. These
edges will not always be able to pass each
other smoothly, and this readjustment
generates smaller shocks.