What causes sericite alteration?
Sericitic alteration or sericitization is a process of mineral alteration caused by hydrothermal fluids invading permeable country rock. Sericitic alteration occurs within the phyllic alteration zone. …
What alters to sericite?
Sericite is produced by the alteration of orthoclase or plagioclase feldspars in areas that have been subjected to hydrothermal alteration typically associated with copper, tin, or other hydrothermal ore deposits. Sericite also occurs as the fine mica that gives the sheen to phyllite and schistose metamorphic rocks.
What causes metasomatism?
In the metamorphic environment, metasomatism is created by mass transfer from a volume of metamorphic rock at higher stress and temperature into a zone with lower stress and temperature, with metamorphic hydrothermal solutions acting as a solvent.
Where does metasomatism occur?
Metasomatism takes place in some rocks adjacent to igneous intrusions (see Contact (thermal) metamorphism; Skarn). It may also affect extensive areas (regional metasomatism), with the introduction of fluids possibly related to partial fusion at depth.
What is silicic alteration?
A process in which the original minerals of a rock become replaced by silicate minerals, this process is caused by the flow of aqueous silica solution through the rocks pore space and over its surface.
What is sericite used for?
Sericite Mica – with Dimethicone Dimethicone is approved as a barrier ingredient, so it is going to offer some protection from the elements. The sericite itself does not offer protection.
What do you mean by metasomatism?
Metasomatism refers to the process whereby a preexisting igneous, sedimentary, or metamorphic rock undergoes compositional and mineralogical transformations associated with chemical reactions triggered by the reaction of fluids (so-called metasomatic agents), which invade the protolith.
Is metasomatism a type of metamorphism?
metamorphic process process is referred to as metasomatism. If a granite is emplaced into a limestone, the contact region may be flooded with silica and other components, leading to the formation of a metasomatic rock.
What is Phyllic alteration in geology?
Phyllic alteration. Phyllic alteration is a hydrothermal alteration zone in a permeable rock that has been affected by circulation of hydrothermal fluids. It is commonly seen in copper porphyry ore deposits in calc-alkaline rocks.
What is Phyllic alteration in porphyry?
Phyllic alteration is often closely associated with argillic alteration, which occurs at lower temperatures and dominantly affects plagioclase. Phyllic alteration typically forms in the base-metal zone of a porphyry system.
What is argillic alteration?
Argillic alteration is hydrothermal alteration of wall rock which introduces clay minerals including kaolinite, smectite and illite. The process generally occurs at low temperatures and may occur in atmospheric conditions.
What is The phyllic alteration of copper?
It is commonly seen in copper porphyry ore deposits in calc-alkaline rocks. Phyllic alteration is characterised by the assemblage of quartz + sericite + pyrite, and occurs at high temperatures and moderately acidic (low pH) conditions.
