VolcanoesVocabulary that you are

accountable for is underlined!

Eruption in Indonesia 1/8/2014

Hot Spots- area of high temp. lava- made Hawaii

View From Space - Klyuchevskaya, Russia

Magma – molten rock beneath the surface

Lava – molten rock on the surface

Types of Volcanoes Composite Cone

or

It’s a composite volcano.

It’s made up of different layers of lava and ash.

A Cinder Cone:

Wizard Island at

Crater Lake, Oregon

Icelandic Volcanoes

Eyjafjallajokull

Tuff Ring: Diamond Head, Hawaii

Shield Volcano: Mauna Loa, Hawaii

Stratovolcano or Composite Cone: Mount Shasta, California

Shastina and Landslide Deposit

Products of Eruptions

Lava Flows • Pyroclastic

Debris • Bombs • Lapilli • Ash • Mudflows• Landslides

Gases

• Steam

• Carbon Dioxide

• H2S

• SO2

• HCl

• HF

Environmental Hazards of Volcanoes

Pollution

• SO2, HCl in Water

Lava Flows

Falling Ejecta

Ash Falls

• Building Collapse • Crop Destruction

Mudflows • Direct Damage (Colombia,

1985) • Floods (Several Types)

Blast (Mt. St. Helens, 1980)

Pyroclastic Flow (St. Pierre, 1902)

Gas (Lake Nyos, Cameroon, 1986)

Pyroclastic Flow or Nuee- Ardente (French: Fiery Cloud)

How Calderas Form:

Crater Lake, Oregon

Colorado Volcanoes ?– La Garita

Evolution of VolcanoesAn active volcanic landscape

Evolution of VolcanoesA volcanic landscape after a million years or so

Mount Hood is a stratovolcano in the Cascades of northern Oregon

The caldera at Crater Lake National Park cuts through the flanks of the former Mount

Mazama (composite cone)

Layers of tephra on Usu (stratovolcano) in Japan. The crater by the volcanologists was formed in

1977-1978.

Eruption of Galunggung (stratovolcano) in

Indonesia.

1980 eruption of Mt. Saint Helens produced 0.1 cubic miles (0.5 cubic km) of ash.

Stratovolcanoes are

associated with

subduction zones, areas

where dense oceanic

plates are pushed

beneath more buoyant

continental plates.

The cinder cone in the above photo is Puu

Lilinue on Mauna Kea in Hawaii.

Cinder cones are produced by "fire fountains," low-energy eruptions that propel

fragments of lava 100s of feet into the air.

A volcanic dome is a steep-sided, rounded extrusion of highly viscous lava squeezed out from a volcano to form a dome-

shaped, or bulbous, mass of lava above and around the volcanic vent

During the 1989-1990 eruption of Redpubt volcano (Alaska) several lava domes grew

and collapsed near the summit of the volcano.

Flood Basalts

• The Columbia River basalts cover parts of the states of Oregon, Washington, and Idaho and are a famous example of flood basalts that produced a lava plain.

Lava• Eruptions under water or

ice produce pillow lava (become pillow basalt)

Coastal Flows

"Pahoehoe" and "aa" are Hawaiian words used

to describe the type of lava volcanoes have

Aa Flow

Pahoehoe

Lava Tubes