metamorphic rock: Quick Facts

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Photos and Videos

metamorphism of banded gneiss

Two rock samples on a flat surface: a dark, shiny schist with a rough texture on the left, and a lighter, layered sandstone on the right.

Diagram of the rock cycle showing how igneous rocks, unconsolidated sediments, sedimentary rocks, and metamorphic rocks transform into each other through processes like weathering, erosion, compaction, cementation, heat, and pressure, with labeled examples and arrows indicating each step.

Diagram of the rock cycle showing the processes that transform sediments into sedimentary rocks, sedimentary rocks into metamorphic rocks, metamorphic rocks into magma, and magma into igneous rocks, with arrows indicating weathering, erosion, melting, cooling, and other key transitions.

photomicrograph of corroded garnet

metamorphic rock: pressure-temperature-time paths

The rock cycle: How different types of rock are formed

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Topics

hornfels greenstone-granite belt granulite–gneiss belt lineation blueschist s-surface porphyroblast metamorphic facies greenstone granulite sedimentary rock igneous rock texture stratification aquifer regolith exfoliation cryoseism bedrock bulging

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Key People

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Friedrich Johann Karl Becke

Austrian mineralogist

Basalt sample returned by Apollo 15, from near a long sinous lunar valley called Hadley Rille. Measured at 3.3 years old.

(Bed) Rocks and (Flint) Stones