Metamorphic rocks start off as some kind of rock. The starting rock can be igneous, sedimentary, or even another metamorphic rock. Heat and/or pressure then change the rock into a metamorphic rock.
CK-12 (Middle School)
How do metamorphic rocks form?
RST.2 - Main Ideas, RST.4 - Key Terms
DEPTH OF KNOWLEDGE (DOK) LEVELS:
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