Download Metamorphic Rocks

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Metamorphism formation of metamorphic
rocks by exposure to high temperature and
pressure within Earth.
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Regional metamorphism is a process that affects
large areas of Earth’s crust depending on pressure
on the rocks, temperature, and depth below the
surface.
Contact metamorphism is the local effect that
occurs when molten rock meets solid rock; high
temperature and moderate to low pressure form
minerals
Hydrothermal metamorphism occurs when very
hot water reacts with rock, altering its mineralogy
and chemistry.
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Foliated: minerals are
squeezed under high
pressure and arranged in
wavy layers and bands.
Nonfoliated: mineral grains
with long axes in one
direction.
Porphydroblasts are large
crystals that form in solid
rock by the reorganization
of atoms during
metamorphism.
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Interactions among Earth’s water, air, land, and
living things can cause rocks to change from
one type to another. The continuous processes
that cause rocks to change make up the rock
cycle.
When magma cools and hardens beneath the
surface or as the result of a volcanic eruption,
igneous rock forms.
Weathered pieces of earth materials are
sediments. Sediments are compacted and
cemented to form sedimentary rock.
Under extreme pressure and temperature
conditions, sedimentary rock will change into
metamorphic rock.