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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