There are many processes talked about in the lecture (and the text) that help create a metamorphic rock. Which one is the only one that is required in that process? Quizlet

Geothermic gradient is the rate of increasing temperature with respect to increasing the depth in the earths interior. away from tech tonic plates boundaries, it is about 25-40 c/km (72-87 degrees f/mi) of depth near the surface in most of the world.