Metamorphic rocks Flashcards
1
Q
Contact metamorphism
A
Magmatic intrusion can subject rocks to high T, Degree of metamorphism declines with distance from the heat source
- The restricted zone around the intrusion is a “contact aureole”
2
Q
Regional metamorphism
A
Occurs over large areas subject to high confining and differential stress
Usually results from tectonic forces that produce compression, as in when two continental masses collide
During collision, rocks are taken from the surface to high T and P
Often occurs in core of mountain ranges
3
Q
Dynamic metamorphism
A
Occurs in narrow zone near faults due to mechanical shear deformation
4
Q
Porphyroblasts
A
Larger, recrystallized grains occurring in a finer groundmass of a
metamorphic rock
