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Volcano NotesMs. Graham and Miss McGee

6th Grade Earth Science

Week 1

November 30 to December 4

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Wk. 1 Day 1

• Before: Volcano Pre-Test• During: Notes form PPT• Exit slip:

– Name the 3 locations that volcanoes are found.

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Individual Volcanoes - Locations

• Subduction Zones:– Association between volcanoes & subduction zones.– Ring of Fire = Ring of Subduction Zones

• Continental Rift Zone:– A few volcanoes are associated with rift zones.– e.g. Kilimanjaro & others in east African rift.

• Hot Spots:– Some coincide with plate boundaries, most don’t.– e.g. Hawaii– Galapagos Is., Iceland, Yellowstone.

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Where are volcanoes located? Is there a pattern?

AT PLATE BOUNDARIES

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Patterns:• Not random• Linear

• Around large inactive plates• Near areas where elevation is changing

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Ring of Fire

There are currently about 1500 activevolcanoes around the world

The Ring of Fire

• The Ring of Fire is an area in the basin of the Pacific Ocean where a large number of earthquakes and volcanic eruptions occur.

• The Ring of Fire is a direct result of plate tectonics and the movement and collisions of lithospheric plates.

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Wk. 1 Day 2

• Before: Question of the Day– Where is the Ring of Fire located?

• Open with Volcanoes by Jimmy Buffett• https://www.youtube.com/watch?v=IjGHwGk

FIFw• Notes

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Volcanoes

Dormant (still has seismic activity and lava flow)**Not currently erupting (but still could

anytime)Active

**Currently erupting

Extinct (no seismic activity, no magma flow)**Not able to erupt (permanently)

GLOSSARYBomb – a lump of rock thrown out in an eruptionCrater – a deep hollow at the top of a volcanoEruption – the release of gases, magma and rock from a

volcanoLava – melted rock that flows down the volcanoMagma – melted rock inside the EarthMolten – melted, liquidVent – a crack on the side of a volcano where magma can

escape

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Volcanoes

• How do volcanoes form?– Deep inside the earth, heat and pressure cause

rock to melt and form magma• Why is magma forced upward toward the

earth’s surface?– Magma is less dense than the rock around it, so it

is forced upward towards the earth’s surface

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Volcanoes

• Where do volcanoes occur?– Along plate boundaries and above hot spots AND

rift boundaries• A hot part in the middle of the mantle that

melts rock that is then forced upward as magma– Hotspot

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Volcanoes

• An example of a volcanic area at divergent plate boundaries– Mid Atlantic Ridge

• An example of a volcano at convergent plate boundaries – Soufriere Hills Volcano

• (Montserrat, West Indies – 1995)

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Volcanoes

• Volcanic eruptions can be– Explosive– Violent– Quiet

• What 3 factors control the style of a volcanic eruption– Water Vapor– Amount of trapped gases– Magma composition

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Volcanoes

• A volcanoes form depends on whether it is the result of a QUIET or and EXPLOSIVE eruption and whether it is made a silica-rich or silica-poor lava.

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Magma!

What is the difference between “lava” and “magma”? Magma is below ground and lava is above ground.

Wk. 1 Day 3

• Before: Question of the Day– What are blocks of lava thrown out of erupting

volcanoes called?• During: Study Jam

• “ Volcanoes”

• After: Exit Slip• Study Jam Quiz

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Wk. 1 Day 4

• Before: Question of the Day– What is the difference between lava and magma?

• During : Review» Mini-Q

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Wk. 1 Day 5

• Before: Question of the Day– The form that a volcano takes depends on what

two things?• During : Review

» Mini Test

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