Formation
Mineral Content
Compound Content
Metamorphism
Types of Metamorphism
Weathering
Types of Weathering
Erosion
Types of Erosion
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.
Calcite, Clay, Clay Minerals
Carbon, Hydrogen, Nitrogen, Oxygen, Sulphur
Burial Metamorphism, Contact Metamorphism, Regional Metamorphism
Variolites are a group of dark green basic igneous rocks that exhibit pale colored spots on weathered surfaces that give them a pockmarked appearance.
Olivine, Plagioclase, Pyroxene
Aluminium Oxide, CaO, Iron(III) Oxide, FeO, Potassium Oxide, MgO, MnO, Sodium Oxide, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional Metamorphism
Biological Weathering, Chemical Weathering, Mechanical Weathering