Metamorphic Rocks

Metamorphic rocks are any one of the three of the rock types that have undergone a fundamental change as a result or heat, pressure, and chemical action of pore fluids and gasses. The effects of metamorphism include: 1) chemical recombination and the growth of new minerals, 2) deformation and realignment of existing mineral grains, and 3) the recrystallization of minerals to form larger grains.

Metamorphic rocks are also identified by their texture, there are two types of textural categories: foliated textures (slaty cleavage, schistosity, gneissic layering), and nonfoliated textures.