Volcanoes form where magma reaches the Earth's surface through openings called vents. There are several types of volcanoes defined by their eruptive activity and structure. Cinder cones have short eruptions that build steep slopes from ejected cinders. Shield volcanoes have long-lasting eruptions that spread lava over large areas to form broad dome shapes like Hawaii's Mauna Loa. Composite volcanoes like Italy's Mount Etna are made of layers from violent and quiet eruptions. Volcanoes can be classified as active if currently erupting, dormant if not currently erupting but historically active, or extinct if no known eruptions in history. Most volcanism occurs along zones of

1. All you need to know about
Volcanoes

3. I Magma –
rocks exist as magma deep with in the
Earth’s crust
II. Lava –
magma that reaches the Earth’s surface

5. 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.

7. I. Cinder cones – made mostly
of cinders and rock particles
a. Explosive eruptions
b. Not high but have a narrow
base and steep sides
c. Izalco in El Salvador and
Paricutin in Mexico

9. a. Quiet flows
b. Flows over a large area
c. Dome-shaped
d. Mauna Loa on Kilauea in
Hawaii (Forms over a hot
spot)

11. 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

13. I.
II.
III.
IV.
Some volcanoes erupt regularly, others
haven’t erupted with in modern history.
Active volcano – is one that erupts
either continually or periodically.
Dormant volcano – one that has been
known to erupt in modern history but is
inactive now.
Extinct volcano – one that has not
been known to erupt in modern history

14. 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.

15. 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.