Lecture 16 metamorphism
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Today’s
Lecture
Chapter 8:
Metamorphic rocks
1) Classification metamorphic rocks
Texture & Composition
2) Contact metamorphism
3) Metamorphism along faults
4) Regional metamorphism
5) Metamorphism & plate tectonics
Agents of metamorphism
Heat
Pressure (stress)
Chemical activity (fluids)
Metamorphic environments
Contact
Cataclastic
Regional
Common metamorphic rocks
gneiss
mica schist
quartzite
slate
marble
Common metamorphic rocks
Foliated rocks
Common metamorphic rocks
Foliated rocks
Slate
slate
Fig. 8.13
W. W. Norton
Fig. 8.10
W. W. Norton
Fig. 8.09
W. W. Norton
Common metamorphic rocks
Foliated rocks
slate
Slate
Very fine-grained,
Platy minerals
(Clays, Micas)
COLORS:
black slate
red slate
green slate
CONTAINS:
organic material
iron oxide
chlorite
Common metamorphic rocks
Foliated rocks
slate
Original shale
Slate
TILTING
Rock cleavage
a
n
i
ig
r
O
le
a
h
ls
Common metamorphic rocks
Foliated rocks
Slate
Rock cleavage
a
n
i
ig
r
O
g
n
i
d
d
Be nes
pla
le
a
h
s
l
slate
1) Common
Common
metamorphic
metamorphic
rocks
rocks
Foliated rocks
Slate
Original
sedimentary
layering
slate
Fig. 8.12a
W. W. Norton
Veins developed
in slate
Common metamorphic rocks
Foliated rocks
phyllite
Phyllite
Fine- to medium-grained
Platy minerals(e.g.
muscovite or chlorite
Phyllite
Slate
Common metamorphic rocks
Foliated rocks
phyllite
Phyllite
Biotite Mica
Common metamorphic rocks
Foliated rocks
phyllite
Original
sedimentary
layers
Phyllite
1) Common metamorphic rocks
Foliated rocks
schist
Schist
Coarser-grained
Strongly foliated
Easy to split in
slabs
Pioneer Range, Idaho
Common metamorphic rocks
Foliated rocks
schist
Mica Schist
Rock name:
Composition plus texture
Common metamorphic rocks
Foliated rocks
Schist
Segregation
of minerals
into bands
Quartz
Micas
schist
Schist
Quartz
Mica
Common metamorphic rocks
Foliated rocks
Schist
Segregation
of minerals
into bands
Begins.
schist
Common metamorphic rocks
Foliated
Rocks
Foliated
rocks
schist
Schist
Appearance
of new minerals
Amphibole
