AMSTI VOLCANOES

Download Report

Transcript AMSTI VOLCANOES

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