Metamorphic Rocks

Igneous rocks start as molten material that cools and solidifies into solid rock. Sedimentary rocks begin as weathered materials that become consolidated into one solid mass through the process of cementation.  In both cases, rock-forming materials (lava, magma, and sediments) solidify to form new rock. Metamorphic rock formation is completely different, and as a result, can be a little confusing. This rock type begins as a solid and ends as a solid.  Metamorphic rocks start out as rock, whether it is igneous, sedimentary, or metamorphic. Then, the rock is exposed to heat and pressure and change occurs, creating a new rock. The forces needed to change a rock are found deep within the Earth’s crust.  This new rock will exhibit new textures and can even have a new composition.