Download Nonfoliated metamorphic rocks

Chapter 3 Sec 3 Metamorphic Rocks
Let’s Review: What is
an igneous rock?
What does the Latin
word for Igneous
mean?
How does it form?
What two ways is it
classified?
How does it change
into different rocks?
Chapter 3 – Section 3
Metamorphic Rocks
What is a metamorphic
rock?
The word metamorphic
means to “change
form”
Notes
Chapter 3 – Section 3
Metamorphic means to “change form”
Metamorphic rocks
are rocks that have
changed because of
temperature and
pressure or the
presence of hot
watery fluids.
oMetamorphic rocks change because of
temperature and pressure or
the presence of hot watery
fluids.
The form and/or the
composition of the
rock can change.
See pg. 67 – figure
7.
When heat and
pressure are
applied to granite
(an igneous rock),
the new rock is
gneiss.
Example – when heat and
pressure are applied to
granite (igneous rock) a new
rock called gneiss is formed.
Igneous granite.......................... changes
to metamorphic gneiss
Metamorphic rocks
can form from
sedimentary rocks,
igneous rocks, or
other metamorphic
rocks
This is
the rock
cycle
As pressure and temperature
continue to increase over time,
one type of rock can change into
several different metamorphic
rocks
Here’s a short
clip about
metamorphic
rock
Heat and Pressure
Where does the heat and
pressure come from?
Rocks below Earth’s surface are
under tremendous pressure from
rock layers above them.
Temperature increases with depth
in the Earth.
Sometimes
temperature
and pressure
are great
enough to melt
rock, forming
magma
Sometimes, the rock
is not actually
melted but the
pressure can flatten
the mineral grains in
rocks, therefore
making a new rock.
As pressure and
temperature
continue to
increase over time,
one type of rock
can change into
several different
metamorphic
rocks.
Example – With heat and
pressure Shale can turn into
slate.
With additional heat and
pressure, slate can turn into
phyllite.
Adding more heat and pressure,
phyllite turns into schist…and so
on.
Example
Shale (parent rock)
Slate
Phyllite
Schist
Adding heat
and
pressure to
each type of
rock causes
it to change
and a new
type of rock
forms
Hot Fluids
Fluids can also move
through rock
Fluids are mostly water
and dissolved elements
or compounds – they
can react and
chemically change the
rock into something
else.
(See pg. 68 – figure 8)
Rocks surrounding
a hot magma body
can react to the hot
magma. These
fluids are mainly
comprised of water
and carbon
dioxide.
Classifying
Metamorphic Rocks
Foliated or
nonfoliated?
Foliated metamorphic rocks –
when mineral grains line up in
parallel layers. Example: slate
and gneiss
Slate is layered and often used
for paving around pools and
patios because the layers are
pressed so firmly together that
they are watertight
Folitated
Slate comes in several colors.
Used for chalkboards,
more expensive upper end pooltables,
yard stepping stones….
Classifying Metamorphic Rocks
Foliated – when mineral grains line up
in parallel layers.
Example: Slate, gneiss
Nonfoliated
metamorphic
rocks – minerals
do not form
layers.
Examples:
quartzite and
marble
marble
Nonfoliated – minerals do not line up in
layers
Example: quartzite, marble (both have
several different colors)
Here’s a short
clip about
diamond which is
a mineral formed
from
metamorphic
rock