metasomatic metamorphism

mineralogy

Also known as: metasomatism

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July 23, 2026

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Metasomatic metamorphism involves changes in rocks due to the addition or subtraction of chemical components, often occurring near igneous intrusions. This process, also known as metasomatism, can lead to rocks with unique compositions and zoned structures as elements diffuse across boundaries of dissimilar materials. For instance, when granite intrudes limestone, the contact zone can become enriched with silica and other components, forming a metasomatic rock.12

Metamorphism, in general, is the alteration of existing rocks (igneous, sedimentary, or other metamorphic rocks) due to changes in temperature, pressure, and chemical environment. These changes can lead to recrystallization and the formation of new mineral assemblages. The specific minerals present in a metamorphic rock are dictated by its original chemical composition and the pressure-temperature conditions it experiences, as described by the Gibbs phase rule.321

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metamorphism
…to decreasing temperature and pressure; metasomatism, the metamorphism that includes the addition or subtraction of components from the original assemblage; poly-metamorphism, the effect of more than one metamorphic event; and hydrothermal metamorphism, the changes that occur in the presence of water at high temperature and pressure which affect the resulting…
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…to decreasing temperature and pressure; metasomatism, the metamorphism that includes the addition or subtraction of components from the original assemblage; poly-metamorphism, the effect of more than one metamorphic event; and hydrothermal metamorphism, the changes that occur in the presence of water at high temperature and pressure which affect the resulting…
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metamorphic rock
Thermodynamics of metamorphic assemblages
…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. Often such contacts are chemically zoned. A simple example is provided by the metamorphism of magnesium-rich igneous…
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…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. Often such contacts are chemically zoned. A simple example is provided by the metamorphism of magnesium-rich igneous…
Read More