Formation
Eclogite forms from high-pressure metamorphism of mafic igneous rocks mainly, basalt or gabbro as it plunges into the mantle in a subduction zone.
Anthracite forms from the accumulation of plant debris in a swamp environment. When plant debris dies and falls into the swamp, the standing water of the swamp protects it from decay.
Composition
Mineral Content
Amphibole, Coesite, Corundum, Dolomite, Garnet, Kyanite, Lawsonite, Paragonite, Phengite, Pyroxene, Quartz, Rutile, Zoisite
Calcite, Clay, Clay Minerals
Compound Content
Aluminium Oxide, NaCl, CaO, Carbon Dioxide, Iron(III) Oxide, Magnesium Carbonate, MgO, Sodium Oxide, Potassium, Sodium
Carbon, Hydrogen, Nitrogen, Oxygen, Sulphur
Transformation
Metamorphism
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Types of Metamorphism
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Burial Metamorphism, Contact Metamorphism, Regional Metamorphism
Weathering
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Types of Weathering
Mechanical Weathering
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Erosion
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Types of Erosion
Chemical Erosion, Sea Erosion
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