volcano types and volcanic eruptions

Volcano Types and Volcanic Eruptions

1. Why Volcanoes Erupt:

• The F of expanding gas builds and pushes magma through the vent

2. Major Factors in Eruptions:

• a. The amount of trapped gas

– CO2 and Sulfur

• b. Silica Content– The more silica, the

more explosive

C. Common Volcano Products

–Ash:• Fine rock particles, less than 1/10 of

an inch

C. Common Volcano Products– Cinder

• Rock pieces at least 2.5 inches to many feet

C. Common Volcano Products• Pyroclastic Flow:

– Mix of hot ash, bombs, gas, pumice and glass that can travel up to 100 miles per hour.

3. Common Volcano Types• Shield Volcano

– Structure– Composition

• Layers of built up lava

– Eruption Type• Quiet

– Lava Type• Pahoehoe

– Hazards• Burning land, ash covered

– Example• Hawaiian Islands

3. Common Volcano Types• Cinder Cone

– Structure– Composition

• Layers of ash, cinders and bombs

– Eruption Type• Explosive

– Lava Type• Aa

– Hazards• Deadly gasses, landslides, avalanche, pyroclastic

flow

– Example:• Paricutin, Mexico

3. Common Volcano Types• Composite

– Structure– Composition

• Alternate lava and ash

– Eruption Type• Alternate Quiet and explosive

– Lava Type• Pahoehoe and Aa

– Hazards• Alternate

– Example:• Mt. St. Helens

4. Volcanic Activity

• a. Common Volcano Locations

Volcanoes per Continent

050

100150200250

Austra

lia

South

Am

erica

North

Am

erica

Asia

Europ

e

Africa

Antar

ctica

Australia

South America

North America

Asia

Europe

Africa

Antarctica

b. Volcanic Eruption simulation

• http://discoverykids.com/games/volcano-explorer/

4. Volcanic Activity

• b. Life Cycle:– Active

• A volcano likely to erupt soon– Ex. Mt. Fuji and Mt. St. Helens

– Dormant• A Volcano that may erupt in the future

– Mt. Hood, Oregon and Mt. Kilimanjaro, Africa

– Extinct:• A volcano unlikely to erupt (10,000 years)

– Mt. Buninyong, Australia