VOLCANOS

MT HOOD

• Mount Hood is a stratovolcano in the Cascade Volcanic Arc of northern Oregon.
• formed by a subduction zone on the Pacific coast
• Last erupted 1866
• Active volcano
• 11,250ft high

POPOCATÉPETL

• The volcano is the second highest mountain in Mexico
• 17,802 ft high .
• Last eruption Dec 2000
• Active volcano

WHAT CREATES VOLCANOS

• Spreading plate margins
• Subducting plate margins

MAGMA AND LAVA

• Lava is magma that reaches the surface of our planet through a volcano vent
• Magma is composed of molten rock and is stored in the Earth's crust.

CLASSIFICATION

• active volcano is one that has erupted since the last ice age (i.e., in the past ~10,000 years).
• dormant volcano would then be one that hasn’t erupted in the past 10,000 years
• extinct volcano would be one that nobody expects to ever erupt again.

EFFECTS

• Plants are destroyed over a wide area, during an eruption.
• Eruptions can influence bird migration, roosting, flying ability, and feeding activity.