Classifying Metamorphic Rocks
Flashcards
Background: Metamorphic rocks are classified based on how they form, their composition, and their textures.
There are two major types of metamorphic rocks: foliated and nonfoliated.
FOLIATED
These rocks occur
when mineral grains
line up in parallel
layers.
METAMORPHIC
Rocks that have changed
because of changes in
temperature and pressure
or presence of hot fluids
FOLIATED
Slate and gneiss are
examples of this type
of metamorphic rock.
NONFOLIATED
Mineral grains are
grown and rearrange,
but do not form layers.
NONFOLIATED
METAMORPHIC
Layering of minerals
does not occur in this
type of metamorphic
rock.
Depending on the heat
and pressure, this type
of rock can form from
several types of rocks.
METAMORPHIC
Can form from
igneous, sedimentary,
or metamorphic rocks.
NONFOLIATED
Marble is this type of
metamorphic rock.
NONFOLIATED
When sandstone is heated
under lots of pressure, it
forms quartzite. Quartzite
is a ______ rock.
METAMORPHIC
Can form when
minerals dissolve and
recrystallize (reform)
when near hot fluids.
METAMORPHIC
These rocks can form
in the presence hot
fluid without melting.
METAMORPHIC
METAMORPHIC
METAMORPHIC
These rocks are
classified by texture
and composition
(What it is made of)
Rocks that change
because of changes in
temperature and
pressure
Granite changes to
Gneiss when pressure
is
applied
NONFOLIATED
A metamorphic rock
that does NOT have
mineral grains that line
up. The minerals grow
andMarble
spread out
MARBLE
Slate
FOLIATED
Gneiss
FOLIATED
Quartzite
NONFOLIATED
YES/NO
YES/NO
The pressure needed to
change a metamorphic
rock comes from all of
the rock layers above
pressing down on it
The temperature
needed to change a
rock comes from the
higher temperatures
found as you go deeper
inside the crust