Formation
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.
Picrite is a fine-grained, hard rock which is a type of metasomatite, essentially altered basalt. It forms with or without crystallization, either below the surface as intrusive rocks or on the surface as extrusive rocks.
Composition
Mineral Content
Clay Minerals, Pyrite, Quartz, Sulfides
Biotite, Olivine, Plagioclase, Pyrrhotite
Compound Content
NaCl, CaO, Carbon Dioxide, Magnesium Carbonate, MgO
Al, CaO, Carbon Dioxide, Mg, MgO
Transformation
Metamorphism
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✘
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Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Regional Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Impact Metamorphism, Regional Metamorphism
Weathering
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✘
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✘
Types of Weathering
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Biological Weathering
Erosion
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✘
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Types of Erosion
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Chemical Erosion, Coastal Erosion, Glacier Erosion, Sea Erosion, Water Erosion, Wind Erosion