Metamorphic Rocks

Science, Grade 6


Table Of Contents: Metamorphic Rocks

1. Formation of Metamorphic Rocks
Metamorphic rocks are formed from any type of rock that changes as a result of intense heat and pressure in the Earth's crust.
2. Shale Metamorphism
For example, as sedimentary shale is exposed to more heat and pressure, it changes into different types of metamorphic rocks.
3. Contact and Regional Metamorphism
Contact metamorphism occurs when rocks come in contact with magma. Regional metamorphism occurs when intense pressure, such as mountain formation, changes large-scale areas of rocks.
4. Foliated Metamorphic Rock
Metamorphic rocks are classified as foliated or nonfoliated. Foliated rocks have grains arranged in thin parallel layers or bands. Slate and gneiss are examples.
5. Nonfoliated Metamorphic Rock
Nonfoliated metamorphic rocks have a random arrangement of crystals or grains without layers or banding. Examples include marble and quartzite.
6. Metamorphic Rock Uses
Metamorphic rocks are used primarily for construction purposes. Marble is used for decorative statues, columns and flooring. Slate is used for roofing and walkways.