Earthquakes and
Volcanoes Study Guide
Faults

Normal Fault:
 Plate
boundary- divergent
 Stress-

Reverse Fault:
 Plate
boundary- convergent
 Stress-

tension
compaction
Strike-slip Fault:
 Plate
boundary- transform
 Stress-
shear
Seismic Waves



P waves:

Primary waves

Come first

Back and forth motion

Travel through Solids and Liquids
S waves:

Secondary waves

Sideways or side to side motion

Travel through solids only
Surface waves:

Waves on Earth’s surface

Cause the most damage

Circular movement
Focus/Epicenter

Focus:
 Starts
 Right

deep within the earth along the fault line
where the rupture occurs
Epicenter:
 Point
Earth
directly above the focus, on the surface of the
Hot Spots

Areas on Earth’s mantle where high temperature causes sections of Earth to
rise

Heat melts the rock that is forced to the surface

Form away from plate boundaries

Examples: Hawaii, Yellowstone
Composite Volcano

Eruption:
 Alternate
between explosive and non-explosive
eruptions
 Sometimes
runny lava, sometime pyroclastic material
type lava
 Wide
base/steep sides
 Most
dangerous
 Alternate
between explosive and non-explosive
eruptions
 Most
dangerous
Cinder Cone Volcano

Smallest, but most explosive

Lava that breaks up and shoots into the air
(pyroclastic material)
 Magma

is viscous
Most common volcano
Shield Volcano

Very wide, but shallow/gradual slope

Runny lava

Non-explosive

Get their name from a
warriors shield

Ex: Mt. Eta