Formation
Dacitic magma is formed by the subduction of young oceanic crust under a thick felsic continental plate. Further, the Oceanic crust is hydrothermally altered as quartz and sodium are added.
Jasperoid is a rare and peculiar type of metasomatic alteration of rocks. It is formed by extreme alteration of wall rocks within a shear zone which may occur in sediments, andesites, trachytes and basalts.
Composition
Mineral Content
Amphibole, Apatite, Biotite, Feldspar, Garnet, Hornblade, Magnetite, Plagioclase, Pyroxene, Quartz, Zircon
Clay Minerals, Pyrite, Quartz, Sulfides
Compound Content
Ca, Fe, Potassium Oxide, Mg, Potassium, Silicon Dioxide
NaCl, CaO, Carbon Dioxide, Magnesium Carbonate, MgO
Transformation
Metamorphism
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Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Regional Metamorphism
Weathering
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Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
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Erosion
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Types of Erosion
Chemical Erosion
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