The principal reason for the formation of metamorphic rocks is ________

Solution (By Examveda Team)

The principal reason for the formation of metamorphic rocks is extreme heat and pressure. Metamorphic rocks were once sedimentary, igneous or even other metamorphic rocks that have been changed by heat and pressure. Contact metamorphism occurs when magma intrudes or forces its way into existing rock. The heat of the magma bakes the surrounding rocks causing them to change.