Download "Dynamic Earth Guided Notes" (Volcanoes)

Name: ______________________________________________________ Date: _______________________ Period: ________________
Guided Notes – Dynamic Earth
Topic(s): Volcanoes

Don’t you “LAVA” Volcanoes?
o Mr. Parr’s Volcano Video: http://www.youtube.com/watch?v=-nEUUVPTtUI
o Volcano Definition: A vent or hole where molten rock and other volcanic products
have erupted onto the surface. It’s the Earth’s natural way to cool and release pressure.

Fun Facts
o The tallest volcano we know of in the Solar System is on Mars. It is called Olympus
Mons and is 17 miles tall.
o A large volcano eruption can destroy an entire forest.
o The largest volcano on earth is Mauna Loa on the Hawaii Big Island. The tallest is
Mauna Kea, which is right next to it.
o The ash cloud from volcanoes can be dangerous. It can be harmful for people to
breath and difficult for planes to fly through. A large ash cloud from
Eyjafjallajökull, a volcano in Iceland, shut down most of the airports in Europe for
several days in 2010.
o There are generally around 20 volcanoes erupting in the world at any given time.

Types of Volcanoes
o Composite Volcanoes
o Shield Volcanoes
o Cinder Cone Volcanoes

Parts of a Volcano?
o Magma Chamber: An underground storage “tank” for magma near the surface of
the earth.
-
DEMO: Protruding volcanoes – balloon and straw beneath dirt… this
demonstrates how volcanologists track the “growth” of volcanoes.
o Caldera: A collapsed magma chamber. Looks like a crater.
o Volcanic Neck: The peak of a volcano where magma erupts (ejects).
- VIDEO: http://www.youtube.com/watch?v=IAxj2ob_JoU

Parts of a Volcano?
o Pyroclastic Debris Layers: Loose rock and material like ash ejected from a volcano.
o Ash: Volcanic ash consists of fragments of pulverized rock created during volcanic
eruptions, less than 2 mm in diameter. Ash forms during explosive eruptions.
o Lava Flows: The movement of lava on the surface of the Earth. There are 2 main
types of lava flows.

Types of Lava Flows
o Aa: SLOW; breaks easily, jumbled rock flows; very rough surface; angular (pointy),
SHARP.
o Pahoehoe: FAST flowing relative to other lava flows & “ropy” textured; SMOOTH
billowing folds.

DEMO: Physical demonstration of lava flows via walking.
VIDEO: http://www.youtube.com/watch?v=QVyrHqsZiIQ
VIDEO: http://www.youtube.com/watch?v=zmmEWHF_3zY
How FAST does Lava Flow?
o Viscosity: How thick of “runny” a fluid is (like lava).
- DEMO: Volcano model eruption.
- DEMO: Underwater volcano eruption
(http://www.youtube.com/watch?v=6q7N8-Nh4pA)
2
-
DEMO: Syrup vs. Water?  “The Great Race!”

Composite Volcanoes
o Shape: Cone; typical triangular shape
o Size: Highly elevated (8,000+ feet) from their base
o Type of Eruption: Very explosive due to great amounts of water vapor (gas) mixed
into magma
- DEMO: Scoria rock sample.
- DEMO: Bike pump and water bottle rocketexample.
o Other Features: Layers of pyroclastic debris and lava flows.
- DEMO: Candy bar visual.
- DEMO: Clay/Ash layered model.
o Example: Mount St. Helens, Washington, U.S.

Shield Volcanoes
o Shape: Shield; wide base with gradual slopes
o Size: Largest by AREA
o Type of Eruption: NOT very explosive
o Other Features: Layers of ONLY lava flows
o Example: Mauna Loa (… or any Hawaiian volcano)

Cinder Cone Volcanoes
o Shape: Small Cone
o Size: Small in elevation (do not get taller than 1,000 feet in elevation)
o Type of Eruption: Explosive
o Other Features: Made mostly of loose pyroclastic debris
o Example: Sunset Crater, Arizona, U.S.
o Example: Paricutin, Mexico

The BIRTH OF A VOLCANO?
o Subduction Zones: A zone where convergent plate boundaries and trenches exist.
Earthquakes are common in this zone, and volcanoes form nearby.
o Convergent Plate Boundaries: When two tectonic plates move (come) together.
o Partial Melting: the slow melting process of rock into molten rock (magma).
- VIDEO: http://www.youtube.com/watch?v=ryrXAGY1dmE
o Hot Spots: When molten magma from deep within the Earth rises up through the
crust to reach the surface in the middle of tectonic plates. When a hot spot forms
in the middle of a plate, it remains constant, as the plate continues to move over it.
(Ex: Hawaii & Yellowstone).
- VIDEO: Pillow Basalt (the birth of an underwater volcano)
3

Where can Volcanoes be found on Earth?
o Heat Source: A body of air or liquid from which heat is collected. Heat can also be
transferred from one object to another, or from one molecule to another through the
process of conduction.
o Hot Spots
 Convection Currents: Circular motion of molten rock in the asthenosphere
that assists in the formation of volcanoes and the movement of tectonic
plates. (Remember the lava lamp?)
o Ring of Fire: The Ring of Fire is a string of volcanoes and sites of seismic activity,
or earthquakes, around the edges of the Pacific Ocean. It is 40,000 kilometers
long.
 Volcanic Arc: A volcanic arc is a chain of volcanoes positioned in an arc shape
as seen from above. Offshore volcanoes form islands, resulting in a volcanic
island arc. They form near subduction zones.
4


Volcano Application (iPads or iPhones)
o “Volcanoes”  iPad or iPhone Application
o Google Volcano Tracker – GOOGLE EARTH
- http://volcanoes.usgs.gov/
Notable Volcanoes (Google Earth)
o Mount St. Helens (Washington, U.S.)
- VIDEO: http://www.youtube.com/watch?v=_-nBMsKj_c4
- VIDEO: http://www.youtube.com/watch?v=-H_HZVY1tT4
o Vesuvius (Pompeii, Italy)
o Krakatoa (Indonesia)
- VIDEO: http://www.youtube.com/watch?v=5ARBjmoHAII
o Yellowstone National Park SUPER VOLCANO (Wyoming, U.S.)
- VIDEO: http://www.youtube.com/watch?v=Ap_YUwdiy8I
 Old Faithful Geyser:
- VIDEO: http://www.youtube.com/watch?v=hPt6FZzriXQ
o Mauna Loa/Kailua (Hawaii, U.S.)

Magma vs. Lava
o Magma Definition: When rock beneath the Earth's surface gets really hot, it
becomes molten or liquid. While it's still below the surface, it's called magma.
o Lava Definition: Once the magma erupts to the surface through a volcano, it's
called lava. The hotter and thinner the lava is, the farther it will flow. Lava can be
very hot, sometimes as hot as 1000 degrees C.

How “COOL” is Molten Rock?
o Types of Volcanic (Igneous) Rocks
1. Intrusive Rocks: These rocks form when a pocket of magma slowly cools down
enough to form into solid rock. These rocks have LARGE crystals.
- VISUAL: Granite; Diorite: Pegmatite
2. Extrusive Rocks: Extrusive igneous rocks are formed when lava cools and forms
into solid rock. This cooling is much faster. Extrusive igneous rocks have smallgrained crystals.
- VISUAL: Volcanic Glass; Scoria; Basalt
INTRUSIVE (Granite)
EXTRUSIVE (Obsidian/Volcanic Glass)
5
REVIEW PROBLEMS
1.
__________ lava flows are sharp and rigid, whereas _________ lava flows are smooth and fluid in appearance.
a. Aa; Pahoehoe
b. Pahoehoe; Aa
c. Hot; Hotter
d. Unicorn; Pumpkin Cupcake
2.
Which of the follow volcanoes tend to have explosive eruptions?
a. Cinder Cone
b. Shield
c. Composite
d. Both A & C
3.
Which type of volcano is the largest by AREA?
a. Cinder Cone
c. Composite
b. Shield
d. I like turtles…
4.
Which of the following is an example of pyroclastic debris?
a. Ash
b. Aa
c. Pahoehoe
d. Granite
5.
A __________________ forms when a ___________________ collapses.
a. Magma chamber; Hole
b. Hole; Magma chamber
c. Caldera; Magma chamber
d. Cinder cone; Porcupine
6