1/31/2013
1
Metamorphic
rocks form when
the crust is
exposed to rising
pressure and
temperature
conditions. What
processes can
raise the pressure
and temperature
of the crust?
Metamorphic Rocks
Are Composed of
Sedimentary,
Igneous, or
Metamorphic
Minerals that Have
Recrystallized.
Marble from Carrara, Italy
•Pre-existing sedimentary, igneous, or metamorphic rock changed to a new assemblage of
minerals.
•Result of solid-state recrystallization of “parent rock” due to changing crustal conditions.
What Is Metamorphic Rock?
Rocks Evolve through a Sequence of
Metamorphic Grades …
… conveniently
“indexed” by
Index Minerals
