<span>The three agents of metamorphism are heat, pressure, and chemically active fluids. Heat is the most important agent of metamorphism because it provides the energy that drives the chemical reactions responsible for mineral and textural changes during metamorphism.
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You do realize that you could have just looked this up on google... right This answer is in fact from there, and is the answer that pops up when you do a google search on your question...</span>
