Transcript AMSTI VOLCANOES

AMSTI VOLCANOES
Volcano Intro
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Can usually be predicted
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Clues: increased number of earthquakes, presence
of steam & ash, increased amount of sulfur in the air,
and bulging sides/top of volcano
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Accurate predictions save lives & protects property
Volcanoes
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Eruptions range from mild to violent
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Often spew molten rock onto ground & ash into air
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Can erupt sideways
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Can occur with earthquake, flash flood, rockfall, and
mudflow (Lahar)
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Can cause tsunami & melts snow/glaciers
Volcanologist
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Studies volcano
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Observes & collects data
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Collect samples of lava
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Trained in geology,
physics, chemistry,
biology, statistics, math,
and engineering
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Fascinated & curious
about volcanoes & how
they work
Destructive Results
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Ash, contaminated water,
collapsed roofs, electrical
storms, wipe out forests,
mudflows, rockfalls,
earthquakes, flash flood,
ignite fires, tsunami,
lightning, storms,
landslide, destroy crops,
suffocate animals
Constructive Results
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Beautiful hot springs,
recreation, geothermal
energy, produce
electricity, enrich soil with
minerals, creates
gorgeous landscapes
Magma vs Lava
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Magma is under groundLava is above ground
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Hot molten rock below
surface rises through
fractures of crust-can
cool & form rock-can
spew into land or ocean
floor
Viscosity of Lava
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Runny lava flows and covers quickly
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Ricky thick lava oozes slowly
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Magma can retreat & hardens to form caldera
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Viscosity measures the resistance of flow, thickness,
ease of movement and measures friction
Hot Spot & Islands
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Hot spot is are of melting
in the mantle
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Volcanoes form above
hot spots
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If under oceanic crust,
forms an island
Types of Volcanoes
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Shield: gentle flow, 2 separating plates, sloping
sides, wide & flat, flat top, has lava dome, resembles
warrior's shield
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Composite: tall & pointed, snow summits, thick &
sticky lava, 2 colliding plates, lava/ash eruptions,
symmetrical
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Cinder Cone: small, explosive shattering eruptions,
ooze lava at base, magma cools quickly, bowl shape
crater on top, made of pyro clastic material &
cinders/rocks
SHIELD: HAWAII
COMPOSITE:MT FUJI
CINDER CONE:
Rock Cycle
Igneous Rock
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Formation: molten rock
cools and crystallizes on
ground as lava or below
ground as magma
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Examples: IntrusiveGabbro & Granite;
Extrusive-Basalt,
Obsidian & Pumice
Sedimentary Rock
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Formation: Small pieces
of minerals and plants ae
compressed into layers –
often found near water
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Examples: Sandstone,
Shale, Limestone, Coal &
Chalk
Metamorphic Rock
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Formation: Pressed
together by heat &
pressure inside Earth’s
mantle
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Examples: Marble,
Quartz, Slate & Gneiss
YELLOWSTONE
Yellowstone
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National park in
Wyoming & Montana
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Hottest most active
geyser area in world
(500+)
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Most of park sits in an
ancient caldera
Old Faithful
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Most famous geyser at
Yellowstone
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Erupts every 79 minutes
regularly
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Big tourist attraction
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Stem & boiling water
rocket through the
narrowest cracks at the
speed of sound
Geysers
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Water collected under
ground is heated by
magma
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Steam forms, pressure
builds & super hot water
blasts in the air
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If combined with cool
groundwater, a hot spring
will form
Mt St Helen
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State of Washington
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Exploded in 1980
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EQ 5.0 collapsed
mountain causing
landslide
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1 billion to s of ash
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Mudflow & floods killed
63 people
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Erupted for 6 years
The End of Catastrophic Events