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Section 1: Earthquakes occur along faults
Earthquake:
The shaking
that results
from the
movement of
rock beneath
Earth’s surface
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
squeeze
Pull
Stress: A force that
acts on rock
to change
its shape
or volume


either breaks or
changes shape



A break in the Earth’s
crust where slabs of rock
slip past each other
Faults occur when enough
stress builds up in rock
Rocks on both sides of the
fault can move up or down,
or sideways


A type of fault where rocks on either side
move past each other sideways with little
up-or down motion.
Shearing causes these types of faults


A type of fault where the hanging wall
slides downward
Tension forces cause normal faults


A type of fault where the hanging wall
slides up
Compression forces cause reverse faults

The hanging wall
slipped up and
across. If the
footwall had moved
up, the fault would
be called a normal
fault

Faults usually occur along plate
boundaries, where the forces of plate
motion compress, pull, or shear the crust
so much that the crust breaks

Strike-slip faults

Normal faults
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Reverse faults
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high
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How does stress forces affect
rock?
Why do faults form and where do
they occur?
How does movement along faults
change Earth’s surface?