Download Inside the Earth

Mountains
Essential Question:
Explain why Earth’s plates move
Mountains
• There are four main types of mountains:
fault-block, folded, upwarped, and volcanic.
• Each type forms in a different way and can
produce mountains that vary greatly in size.
Mountains
• The ruggedness of a mountain chain
depends largely on whether or not it is still
forming.
Stopped forming
Still forming
Mountains
• Infer what
determines
how rugged
and high a
mountain
chain is.
• Whether or
not it is still
forming.
Mountains
• Sharp, jagged
• Define
mountains made of
fault-block
mountains. huge, tilted blocks of
Sierra Nevada in California
rock that are
separated from
surrounding rock by
faults and form
because of pulling
forces
Mountains
• Describe
how faultblock
mountains
form.
• Rock layers get
pulled in opposite
directions, large
blocks slide
downward, creating
valleys and peaks.
Mountains
• Mountains that form
• Define
by the folding of rock
folded
mountains. layers caused by
compressive forces
Appalachian in Maryland
Mountains
• Describe
how folded
mountains
form.
• Compression: two
plates are pushed
together, this causes
rock layers to buckle
and fold
Mountains
• Define
upwarped
mountains.
Rocky Mountains in Colorado
• Mountains that form
when forces inside
Earth push up on the
crust
Mountains
• Describe
how
upwarped
mountains
form.
• Forces inside Earth
push up the crust;
with time sedimentary
rock layers erode
exposing igneous and
metamorphic rock
Mountains
• Define
volcanic
mountains.
Mt St Helens in Washington
• Mountains that form
when magma is
forced upward and
flows onto Earth’s
surface
Mountains
• Describe
how volcanic
mountains
form.
• Magma from inside
the Earth, called
lava after it reaches
Earth’s surface,
cools. Over time,
layer upon layer of
lava piles up
creating a cone
shaped feature.
Uplift
• If you were to place wooden blocks of
various thickness in a container of water
you would notice that different blocks of
wood would float at different heights.
• The thicker wood would float higher in the
water than the thinner blocks would.
Uplift
• With the blocks, the buoyant force of water
is balancing the force of gravity.
• A similar process called ISOSTASY occurs
in Earth.
• Define
isostasy
• Principle stating that
Earth’s lithosphere
floats on a plasticlike
upper part of the
mantle called the
asthenosphere
Uplift
• The principle of isostasy is why the crust
under mountains is thicker than it is
elsewhere.
• Isostasy also the floating of icebergs.
Mountains
Pictures
• http://www.pitt.edu/~cejones/GeoImages/3Intru
siveBodies/1Plutonsz/1SierraNevada.html
• http://en.wikipedia.org/wiki/Mountain_formation
• http://www.city-data.com/forum/nature/912962how-mountain-ranges-were-created-serious44.html
• http://www.coolgeography.co.uk/GCSE/AQA/R
estless%20Earth/Tectonics/Landforms_at_%20
plate_%20boundaries.htm
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Mountains
Pictures
http://livestockandenvironment.org/?attachment_i
d=443
http://www.oocities.org/williamswindow/landform
s.html
http://en.wikipedia.org/wiki/Mount_St._Helens
http://www.slipperysnake.co.uk/educationalmaterials/geography/volcanoes/
http://volcano.oregonstate.edu/education/vwless
ons/lessons/Earths_layers/Earths_layers5.html
http://thedailyeater.com/?p=4824