Metamorphic Rocks Flashcards
A Non-foliated metamorphic rock derived from fine-grained protoliths through metamorphic aureoles.
Hornfels
Distinguishing feature of Hornfels
Signs of Baking and Chilling
A non-foliated metamorphic rock that contains >90% quartz
Metaquartzite or Quartzite
Protoliths of Metaquartzite
Sandstone or Chert (Quartz-rich Protoliths)
A non-foliated metamorphic rock derived from limestone or dolostone protoliths through dynamothermal, burial, or contact metamorphism.
Marble
Distinguishing feature of Marble
Effervescent and Absence of Fossils
A non-foliated calc-silicate metamorphic rock formed through metasomatism of carbonate metamorphic rocks.
Skarn
Other name of Skarn
Tactite
Distinguishing feature of Skarn
Presence of Calc-silicate minerals (such as Garnets)
A non-foliated rock derived from metamorphism of sedimentary or igneous breccias through dynamic/dynamothermal metamorphism.
Metabreccia
Distinguishing feature of Metabreccia
Mineral and Glass Matrix
A non-foliated cohesive metamorphic rock produced by brittle deformation in low-temperature zones through dynamic metamorphism.
Cataclasite
A non-foliated glassy metamorphic rocks that commonly occur as vein material in cataclastic rocks
Pseudotachylite
Distinguishing feature of Pseudotachylite
Presence of Grains
A non-foliated cataclastic rock formed through tremendous short-term stresses (typically through meteorite impacts)
Impactites
Distinguishing feature of Impactites
Chaotic fragments, Glass components, and Signs of Baking
A non-foliated metamorphic rock that is vitreous with conchoidal fractures formed through burial or dynamothermal metamorphism
Anthracite
A transitional metamorphic rock derived from conglomerates and contains >2mm sub-rounded clasts from burial, dynamothermal, or contact metamorphism
Metaconglomerate
Distinguishing feature of Metaconglomerate
Specific orientation of clasts (Imbrication)
Imbrication may imply what processes?
The rock formed along waterways with strong currents.
A transitional metamorphic rock that can occur either foliated or non-foliated that forms through hydrothermal alteration of ultrabasic rocks at below ~500 Celsius.
Serpentinite
Serpentinite may occur with???
Clay Minerals
A transitional metamorphic rock that forms through the alteration of ultrabasic rocks or Mg-rich sedimentary rocks
Soapstone
Distinguishing feature of Soapstone
Soft and Soapy feel
A green-colored transitional metamorphic rock rich in silicate minerals that forms low-moderate temperature (200-500 C) alteration.
Greenstone
Where does Greenstone form??
Oceanic Crusts near Divergent Plate Boundaries
Na-rich Basalt that can occur in greenstones
Spilite
Na-rich Andesite that can occur in Greenstones
Keratophyre
A foliated greenstone characterized by the abundance of green minerals
Greenschist
A dark-colored transitional metamorphic rock composed largely of Amphiboles that forms through regional metamorphism of basic igneous/sedimentary rocks
Amphibolite
Amphibolite derived from Basic Igneous Rocks
Ortho-amphibolite
Amphibolite derived from sedimentary protoliths
Para-amphibolite
A transitional metamorphic rock with medium- to coarse-granoblastic grains that forms through high temperature and pressure.
Granulite
A transitional metamorphic rock produced in subduction zones, and characterized by blue minerals
Blueschist
A red and green transitional metamorphic rock derived from basic protoliths that undergoes high pressure and temperature.
Eclogite
What is the alias of Eclogite???
Christmas Rock
A foliated, fine-grained, Al-rich, Pelitic metamorphic rock that is distinguished by its flat, planar cleavage and dull luster developed through low temperature and pressure
Slate
A foliated metamorphic rock characterized by its phyllitic cleavage and glossy sheen developed by recrystallization of slate
Phyllite
What causes the glossy sheen of Phyllite????
Sericite (fine-grained mica)
A foliated metamorphic rock characterized by schistosity and rich in aluminosilicate minerals formed through dynamothermal metamorphism at convergent plate boundaries
Schist
Distinguishing feature of Schist
Shiny Luster
What causes the shiny luster of Schist???
Macrocrystalline Mica
A foliated metamorphic rock with a gneissose structure that formed from lower-grade metamorphic rock and dynamothermal settings
Gneiss
Gneisses that developed from Igneous Protoliths
Orthogneiss
Gneisses that developed from Sedimentary Protoliths
Paragneiss
A foliated “mixed” metamorphic rock that possesses textural and structural characteristics of both igneous and metamorphic rocks
Migmatite
Distinguishing feature of Migmatite
Swirling mix of colors (Myrmekitic)
Banded metaquartzite that contains 20-30% Iron
Taconite
Deformed metamorphic rock that have their original composition, but texture largely obliterated
Tectonite
A by-product glassy rock produced by the explosion during the Trinity Test
Trinitite
