Lab 06 - Metamorphic Rock Identification Key

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Lab 06 - Metamorphic Rock Identification Key 1. slate, phyllite, schist --> shale protolith gneiss -- > granite protolith 2. quartzite --> sandstone protolith hornfels --> shale protolith marbles --> limestone protolith skarn --> dirty limestone protolith 3. igneous rocks = crystallization; metamorphic rocks = recrystallization 4. 3 kilometers per 1 kilobar 5 & 6. SKIP for now 7. false; under high T and high P 8. quartzite (pure quartz like a sandstone); marble (pure calcite like a limestone) 9. mountain ranges 10. raising magma bodies (with lots of heat and volatiles) 11. recrystallization; mineral rotation & alignment; formation of index minerals 12. shale = detrital texture; slate = foliated texture 13. foliated texture have rock cleavage; non-foliated textures do not 14. hardness; marble is made of calcite; quartzite is made of quartz 15. slate has a foliated texture; hornfels has a non-foliated texture Rock Texture Rock Composition Characteristic Features NAME very fine-grained hardened shale protolith - clays Foliated clays, fine rock cleavage Slate very fine-grained shiny Foliated shale protolith - clays clays with crenulations Phyllite large muscovites and biotites shale protolith - micas + quartz Foliated coarse layered cleavage Schist granite protolith - biotite + quartz Foliated thin red and black bands + orthoclase + Na plag. Gneiss White Nonfoliated limestone protolith - calcite sparkly white calcite rhombs marble sparkly red, hematite colored Pink Nonfoliated limestone protolith - calcite calcite rhombs marble dirty limestone protolith - calcite hard brown and green patches Skarn Nonfoliated + clays + sand with a little white calcite very dense, brownish, looks Hornfels Nonfoliated shale protolith - clays like pieces of old pottery.

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