Formation
Variolites are a group of dark green basic igneous rocks that exhibit pale colored spots on weathered surfaces that give them a pockmarked appearance.
Eclogite forms from high-pressure metamorphism of mafic igneous rocks mainly, basalt or gabbro as it plunges into the mantle in a subduction zone.
Composition
Mineral Content
Olivine, Plagioclase, Pyroxene
Amphibole, Coesite, Corundum, Dolomite, Garnet, Kyanite, Lawsonite, Paragonite, Phengite, Pyroxene, Quartz, Rutile, Zoisite
Compound Content
Aluminium Oxide, CaO, Iron(III) Oxide, FeO, Potassium Oxide, MgO, MnO, Sodium Oxide, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide
Aluminium Oxide, NaCl, CaO, Carbon Dioxide, Iron(III) Oxide, Magnesium Carbonate, MgO, Sodium Oxide, Potassium, Sodium
Transformation
Metamorphism
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Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional Metamorphism
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Weathering
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Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Mechanical Weathering
Erosion
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Types of Erosion
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Chemical Erosion, Sea Erosion