6.3 – Metamorphic Rocks

Causes of Metamorphism Pressure and temp increase with depth When high temp and pressure combine to alter texture, mineralogy, or chemical composition of a rock without melting it, a metamorphic rock forms The high temps required for this ultimately are derived from Earth’s internal heat The high pressures are caused by pressure from the overlying rocks or compressive forces generated during mountain building

The Rock Cycle Metamorphic rocks are formed by the changing of other rocks Igneous, sedimentary, and metamorphic rocks are grouped according to how they form Igneous form from magma, sedimentary from sediments, and metamorphic form from temp and pressure