Metamorphic Rocks
Formation
Pressure, heat, or a combination of these things form metamorphic rocks. It causes minerals in the rock to become unstable and be rearranged into stable mineral formations.
The Types of Metamorphpc Rocks
Contact Metamorphism- a process when magma comes into contact with an existing rock and heat from the magma changes the structure and the mineral composistion of the surrounding rock.
Regional Metamorphism- It is a change in the structure, texture, or the chemical composistion of a rock caused by a change of temperature or pressure over a large area, which are ususally a result of the shifting of tectonic plates.
Regional Metamorphism- It is a change in the structure, texture, or the chemical composistion of a rock caused by a change of temperature or pressure over a large area, which are ususally a result of the shifting of tectonic plates.
The Classifications of Metamorphic Rocks
Foliated Rocks- Foliated rocks form when either extreme pressure causses the mineral crystals to realign or regrow, which forms parallel bands, or when minerals that have different compositions seperate to create a series of light and dark bands. A few examples of this type of rock are gneiss, schist, and slate.
Nonfoliated Rocks- They are metamorphic rocks that do not have aligned minerals or bands. Two characteristics of nonfoliated rocks are when the original rock contains only the grains of one mineral with small traces of other minerals and/or the original rock contains round or square grains. Marble and quartzite are examples pf this type of rock.
Nonfoliated Rocks- They are metamorphic rocks that do not have aligned minerals or bands. Two characteristics of nonfoliated rocks are when the original rock contains only the grains of one mineral with small traces of other minerals and/or the original rock contains round or square grains. Marble and quartzite are examples pf this type of rock.