Question

What is metamorphism? What are its causes?

Answer 1

Metamorphism is the change of minerals or geologic texture (distinct arrangement of minerals) in pre-existing rocks (protoliths), without the protolith melting into liquid magma (a solid-state change).[1] The change occurs primarily due to heat, pressure, and the introduction of chemically active fluids. The chemical components and crystal structures of the minerals making up the rock may change even though the rock remains a solid. Changes at or just beneath Earth's surface due to weathering and/or diagenesis are not classified as metamorphism.[2] Metamorphism typically occurs between diagenesis (max. 200°C), and melting (~850°C).[3]

Answer 2

Hey...
Your answer is here
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A change of the form or nature of a thing or person into a completely different one is known as metamorphism.

Its causes are:
☆The change occurs primarily due to heat, pressure, and the introduction of chemically active fluids. The chemical components and crystal structures of the minerals making up the rock may change even though the rock remains a solid. Changes at or just beneath Earth's surface due to weathering and/or diagenesis are not classified as metamorphism.

☆Metamorphism typically occurs between diagenesis (max. 200°C), and melting (~850°C).
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