Some metamorphic rocks

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Transcript Some metamorphic rocks

UNIT
10
Consequences of lithospheric dynamics
SOME METAMORPHIC ROCKS
Biology and Geology 4. Secondary Education
UNIT
UNIT
10
3
Some metamorphic rocks
Schist
Shale
Gneiss
Foliated
Metamorphic
rocks
Marble
Non-foliated
Pulsa en las imágenes
Biology and Geology 4. Secondary Education.
Quartzite
UNIT
UNIT
10
3
Some metamorphic rocks
FOLIATED METAMORPHIC ROCKS
Shale
Appearance
Black or dark brown-grey rock formed by
overlapping plates.
How it appears in nature
In strata, in flattened pastry-like sheets.
Composition
Quartz and muscovite (mica), resulting
from the metamorphism of clay minerals
which they come from.
Texture
Sheet-like grains overlapping and oriented
in the same direction.
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Biology and Geology 4. Secondary Education.
UNIT
UNIT
10
3
Some metamorphic rocks
FOLIATED METAMORPHIC ROCKS
Schist
Appearance
Grey rock with reddish-brown, white or
black veins.
How it appears in nature
In strata, in flattened sheets.
Composition
Muscovite (mica), talc, chlorite and
frequent inclusions of quartz and garnet.
Texture
Large grains, layered, overlapping and
oriented in the same direction.
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Biology and Geology 4. Secondary Education.
UNIT
UNIT
10
3
Some metamorphic rocks
FOLIATED METAMORPHIC ROCKS
Gneiss
Aspecto
Roca de color gris con marcadas bandas
oscuras y claras alternadas.
Forma en que aparece en la naturaleza
En grandes estratos a menudo muy
plegados.
Composición
Cuarzo, feldespatos y micas.
Textura
Minerales dispuestos en bandas con
ocasionales inclusiones entre ellas de
grandes granos de feldespato.
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Biology and Geology 4. Secondary Education.
UNIT
UNIT
10
3
Some metamorphic rocks
NON-FOLIATED METAMORPHIC ROCKS
Marble
Appearance
Grey rock with clear alternating dark and
light bands.
How it appears in nature
Often in very folded large strata.
Composition
Quartz, feldspars and mica.
Texture
Minerals arranged in bands with
occasional large inclusions including
feldspar grains.
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Biology and Geology 4. Secondary Education.
UNIT
UNIT
10
3
Some metamorphic rocks
NON-FOLIATED METAMORPHIC ROCKS
Quartzite
Appearance
Very compact white, cream or reddish-
brown rock.
How it appears in nature
In very thick layers that often stand out as
large crests in the area due to the rock’s
high resistance to erosion.
Composition
Quartz.
Texture
Small grains of the original sandstone
closely linked by a cement, also from
quartz.
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Biology and Geology 4. Secondary Education.