Download 185 Mountains, volcanoes, and earthquake... 20KB Dec 06 2012 03

Plate Tectonics -
Name______________________
as they relate to earthquakes, volcanoes, and mountain formation.
Event
Earthquake
Definition
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Shaking/vibration of earth’s
crust due to rough movement
between 2 tectonic plates.
3 classes of earthquakes:
Shallow, intermediate, deep
Tectonic Terms
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Stress built up as 2 plates
shear against each other.
Energy released from plates
In seismic waves.
Focus-is the origin where
the shearing first occurs.
Epicenter-ground level
location above focus.
Human
Impact/Technology
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Volcano
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Formed when 2 plates collide,
and one subducts, or goes under
the other.
Plates diverge as magma forces
up between 2 plates in ocean
crust.
Also found in areas called “hot
spots” around Hawaii, where
there is significant amounts of
underwater Magma.
Volcanoes can exist both in
oceanic and continental crust.
3 different types of volcanoes-
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Volcanoes “erupt” when
pressure needs to be
released from the earth’s
interior as a result of plate
movement activity.
Magma from beneath the
ocean floor or deep within
the earth’s interior forces
itself upwards, or vertically
to release the pressure
through an opening, either
on sea or on land.
Vulcanism- mvmt. of
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Dense populations often
suffer more casualties.
Access to technologies-early
warning systems and
emergency response systems
are important factors for
those living along Mid
Atlantic Ridge.
Seismometer- detects
vibrations caused by
earthquakes. Vibrations
recorded and charted on a
Seismograph.
Richter Scale- number scale
ranging between 0-10, which
measures an earthquake’s
magnitude and intensity.
80-90% of volcanic eruptions
happen near diverging plate
boundaries.(plates spreading
apart).
Volcanoes more active near
major plate boundaries.
Seismometer-can be used to
detect tremors in the earth, as
tremors precede volcanic
eruptions.
Gravimeter- instrument to
measure difference in gravity
from one area to another.
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Shield, composite, and cinder
cone.
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Mountains
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Most are formed when two
continental plates converge and
mass is thrust upward as one
plate folds under the other.
These are called fold
mountains.
Two oceanic plates can
converge, and when the denser
plate subducts, the lighter plate
moves vertically and can form
volcanic island mountains.
Other types of mountains are
Dome, fault block, and plateau.
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molten rock or lava above
or beneath the earth’s
crust.
When magma hits the
surface it is referred to as
“lava.”
Poisonous gases and debris
are also released in addition
lava.
Mountains are visible as a
deformation resulting from
plate tectonic activity, both
on sea and on land.
Mountain formations on
land can take millions of
years versus a much shorter
time frame for other
mountain formations.(eg
volcanic mountains formed
from lava).
Mountain ranges are
constantly being degraded
by processes in weathering
and erosion. This happens
through a much shorter
period of time.
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Used in flow of lava.
Landsat- satellite that uses
infrared sensors in detection
of temperature changes in
earth.
Also monitors levels of sulfur
dioxide and other gases
released from the ground in
higher amounts prior to
volcanic eruptions.
Large mountains can create
varying climates on either side
of mountain.
Mountains provide
recreational activities like
hiking, skiing, camping,
photography, etc.
Maintain water sources longer
as compared to lower
elevations.