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http://www.youtube.com/watch?v=7LDMgxF56s4http://www.neok12.com/php/watch.php?v=zX616a577c597f7c784c720a&t=Types-of-Rockshttp://www.neok12.com/php/watch.php?v=zX616a577c597f7c784c720a&t=Types-of-Rockshttp://www.youtube.com/watch?v=7LDMgxF56s4
Metamorphic Rocks
on the road to something new…
Regents Earth Science
with Ms. Connery
http://www.youtube.com/watch?v=W2xnZ-2HNW4
To metamorphose something
means to
change something from
one form to another
metamorphism
extreme heat
extreme
pressure
contact
metamorphism
regional
metamorphism
foliated
non-foliated
deformation
mineral
alignment
How do metamorphic rocks form?
You know it’s metamorphosed if change has occurred!
Metamorphism happened here because layers were originally
horizontal
TECTONIC PRESSURE
APPLIED
BEFORE FOLDING
DEFORMED (FOLDED) from
EXTREME PRESSURE of
REGIONAL METAMORPHISM
AFTER
Extreme heat of igneous magma intrusion
causes CONTACT METAMORPHISM
YOUNGEST SED.
LAYER
OLDEST SED.
LAYER
Contact
metamorphism
http://www.google.com/url?sa=i&rct=j&q=&esrc=s&frm=1&source=images&cd=&cad=rja&uact=8&docid=APBSptt0Nkq-aM&tbnid=C9mAybxy7XHbEM:&ved=0CAUQjRw&url=http://www.troy.k12.ny.us/old sites/faculty/dibarij/earth science/answer13_14.html&ei=04mYU-_GH5HMsQTBpYKgBg&bvm=bv.68693194,d.aWw&psig=AFQjCNGVQ8DfEXG6NEMkqYNP_3PuWSlGKw&ust=1402592021319289http://www.google.com/url?sa=i&rct=j&q=&esrc=s&frm=1&source=images&cd=&cad=rja&uact=8&docid=APBSptt0Nkq-aM&tbnid=C9mAybxy7XHbEM:&ved=0CAUQjRw&url=http://www.troy.k12.ny.us/old sites/faculty/dibarij/earth science/answer13_14.html&ei=04mYU-_GH5HMsQTBpYKgBg&bvm=bv.68693194,d.aWw&psig=AFQjCNGVQ8DfEXG6NEMkqYNP_3PuWSlGKw&ust=1402592021319289
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http://www.youtube.com/watch?v=7LDMgxF56s4http://www.neok12.com/php/watch.php?v=zX616a577c597f7c784c720a&t=Types-of-Rockshttp://www.neok12.com/php/watch.php?v=zX616a577c597f7c784c720a&t=Types-of-Rockshttp://www.youtube.com/watch?v=7LDMgxF56s4
Overview of Metamorphic Rocks
http://www.youtube.com/watch?v=1oQ1J0w3x0o
“REGIONAL” metamorphism
• Change caused by from extreme
heat and pressure
• REGIONAL metamorphism means
change at a LARGE scale over
LARGE area
IGNEOUS
METAMORPHIC
ESRTs - Regional metamorphism
• NO MELTING…just rearranging and lining
up the same mineral crystals
• Grade of metamorphism depends on
how long the process goes on
• Deeper with more heat & pressure &
longer time more change occurs
Foliation when the minerals
align perpendicular to the
pressure being applied
Regional metamorphism… Rocks show
an increase in foliation & deformation as
metamorphism continues
Which way
was the
pressure
applied?
Foliation - minerals align or “line up”
perpendicular to the pressure
Scheme for Metamorphic Rock Identification
Increased pressure from
regional metamorphism
causes foliation to
progress
shale phyllite
schistgneiss
slate
http://www.gc.maricopa.edu/earthsci/imagearchive/banded_gneiss_big.jpghttp://www.gc.maricopa.edu/earthsci/imagearchive/banded_gneiss_big.jpg
Increased pressure from regional metamorphism
changes bituminous to ANTHRACITE coal
http://www.mii.org/mineral_photos_by_type.htm#meta
What’s different?
This metamorphic rock is NOT
FOLIATED - it doesn’t have
mineral alignment but it’s harder
than bituminous.
How does the heat of contact
metamorphism changes
sedimentary limestone to
METAMORPHIC MARBLE?
http://www.mii.org/mineral_photos_by_type.htm#meta
HEAT - Contact metamorphism
2 - Diorite (igneous rock) intrusion at 1000s of degrees
3- Limestone changed to MARBLE at edges
http://geology.about.com/library/bl/images/blcontactmet.htm
1 - Existing Rock = LIMESTONE
1 - Existing Rock = LIMESTONE
3 - Limestone changed to MARBLE at edges
HEAT - Contact metamorphism
• Extreme heat of contact of an existing
rock with an igneous (magma) intrusion or
lava causes some existing rock to melt
and become part of the magma.
• Along the edges (contact zone) where not
quite hot enough to melt the existing rock,
it “changes” the rock through
recrystallization (but not melting!).
Let’s ID some Metamorphic Rocks!
Conceptual Model: Extreme heat of
Contact metamorphism