All you need to know about

Volcanoes

http://video.nationalgeographic.com/video/environment/environment-natural-disasters/volcanoes/volcanoes-101

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http://www.youtube.com/watch?v=4aYQixhdWY4&feature=fvwrel

Parts of a Volcano

I Magma – rocks exist as magma deep with in the Earth’s crust

II. Lava – magma that reaches the Earth’s surface

III. Volcano – the place in the Earth’s surface through which magma and other materials reach the surface

IV. Vent – opening in which lave erupts – sometimes has more than one.

Types of Volcanoes

I. Cinder cones – made mostly of cinders and rock particles

a. Explosive eruptionsb. Not high but have a narrow

base and steep sidesc. Izalco in El Salvador and

Paricutin in Mexico

Cinder Cone

II. Shield Volcano

a. Quiet flowsb. Flows over a large areac. Dome-shapedd. Mauna Loa on Kilauea in

Hawaii (Forms over a hot spot)

Shield Volcano

III. Composite Volcano

a. Made up of alternating layers of rock particles and lava

b. First eruption violent, second eruption quiet (this is continuous until the volcano is formed)

c. Mount Etna in Italy

Composite

Volcanic Activity

I. Some volcanoes erupt regularly, others haven’t erupted with in modern history.

II. Active volcano – is one that erupts either continually or periodically.

III. Dormant volcano – one that has been known to erupt in modern history but is inactive now.

IV. Extinct volcano – one that has not been known to erupt in modern history

Volcano and Earthquake Zones

I. Most major earthquakes and volcanic eruptions occur in three

zones of the world. Scientists believe that there is great deal of

movement and activity in the Earth’s crust in these zones.

3 major Zones

II. Ring of Fire – zone goes through the edge New Zealand, the Philippines, Japan, Alaska, and along the western coast of North and South America. Mediterranean Zone – extends across Asia into

India

III. Iceland to the middle of the Atlantic Ocean

Iv. Mid-Atlantic Ridge – long mountain range of volcanic mountains under the Atlantic Ocean

V. New parts of the Earth are forming in this area.

Ring of fire

Mediterranean zone

Mid-Atlantic Ridge