Metamorphic Rocks

Explain how collisions of Earth's plates can cause contact metamorphism.

Collisions between Earth's plates can push rock down toward the heat of the mantle to cause contact metamorphism.

How do geologists classify metamorphic rock?

Geologists classify metamorphic rocks according to the arrangement of the grains making up the rocks.

Explain how plate movement and collisions can cause regional metamorphism.

Plate collisions cause great pressure to be applied to rocks while mountains are being formed. The pressure can deform the rock.

Explain how pockets of magma can cause contact metamorphism.

Pockets of magma can rise through the crust. The high temperatures of these pockets can change rock into metamorphic rock.

Besides mineral composition, name 3 things about a rock that can change due to metamorphism by extreme heat and pressure.

The appearance, texture, and crystal structure of the minerals in a rock change.

Regional metamorphism

affects rock over a large area from heat and pressure, caused from plate shifting or colliding

Metamorphic rock is classified as either

foliated or non-foliated rock.

Explain how the igneous rock ____ changes into the foliated metamorphic rock, ____.

granite, gneiss

Deep inside Earth both ___ and ____ are much greater than at the Earth's surface. This can change both the rock's ___ and its _____.

heat, pressure; shape, composition

Describe a non-foliated metamorphic rock.

The mineral grains are arranged randomly.

Describe a foliated metamorphic rock.

The rock's grain's are arranged in either parallel layers or bands.

What are the two most useful metamorphic rocks?

1. Marble 2. Slate

What are metamorphic rocks?

Any rock that forms from another rock as a result of changes in heat and/or pressure is metamorphic rock.

Where are many metamorphic rocks found?

Many metamorphic rocks are found in mountains or near large masses of igneous rock.

What properties make marble useful for statues and buildings?

Marble has an even grain, so it can be cut into thin slabs or carved into many shapes. Marble is also easy to polish.

Slate is impermeable to water. What other property of slate makes it useful as roofing material?

Slate is foliated, so it splits easily into flat pieces that can be used for roofing.

What can extreme heat and pressure affect the minerals in a rock?

Under very high temperature and/or pressure, the minerals in a rock can be changed into other minerals.

Metamorphic rock can form out of ______, ______ or other _____ rock.

igneous, sedimentary, metamorphic

Extreme pressure squeezes rock so that the mineral grains may line up in flat, parallel __

layers.

The metamorphic rocks ___ and ___ are important materials for building and sculpture.

marble, slate

Foliated

metamorphic rocks that have grains arranged in parallel layer or bands

Non-foliated

metamorphic rocks that have mineral grains arranged randomly

The sedimentary rock ____ can change into the non-foliated metamorphic rock ____. This happens when heat and pressure causes the weakly cemented quartz particles of sandstone to _____ to form quartzite which is extremely _____.

sandstone, quartzite, recrystallize, hard

Another example of a ____ changing into a ______ is limestone changing into _____ because of extreme heat and pressure (on the limestone) deep beneath the surface.

sedimentary rock, non-foliated metamorphic rock, marble

With enough heat and pressure, the sedimentary rock ____ turns into the metamorphic rock, ____.

shale, slate

While metamorphic rocks are forming, intense heat changes the ____ and ____ of the grains, or ______, in the rock.

size, shape, mineral crystals

Deform

to change the physical shape of something

Contact metamorphism

when a magma pocket is touching or in contact with rock, the rock becomes deformed from the heat