Formation
Ignimbrites are formed from very poorly sorted mixture of volcanic ash or tuff and pumice lapilli, commonly with scattered lithic fragments.
Oolites form when layers of calcite are deposited around a sand grain or fossil piece and are rolled around in calm water, which makes them round.
Composition
Mineral Content
Apatite, Biotite, Calcite, Chlorite, Feldspar, Hematite, Hornblade, Ilmenite, Magnetite, Olivine, Pyroxene, Quartz
Calcite, Chert, Clay, Dolomite, Quartz, Sand, Silt
Compound Content
Ca, NaCl
Aluminium Oxide, Ca, NaCl, CaO, Iron(III) Oxide, FeO, MgO
Transformation
Metamorphism
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Types of Metamorphism
Burial 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
Biological Weathering, Chemical Weathering, Mechanical Weathering
Erosion
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Types of Erosion
Chemical Erosion, Coastal Erosion
Chemical Erosion, Coastal Erosion