metasomatism: meaning, definition, pronunciation and examples

C2
UK/ˌmɛtəˈsəʊmətɪz(ə)m/US/ˌmɛdəˈsoʊməˌtɪzəm/

Technical, Academic (Geology, Petrology, Mineralogy)

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Quick answer

What does “metasomatism” mean?

The chemical alteration of a rock by the addition or removal of elements through fluids.

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Pronunciation

Definition

Meaning and Definition

The chemical alteration of a rock by the addition or removal of elements through fluids.

A geological process where the chemical composition of a rock or mineral is significantly changed due to interactions with hydrothermal fluids, often resulting in ore deposits or the formation of new minerals. More broadly, it can be used metaphorically to describe a transformative replacement process in any system.

Dialectal Variation

British vs American Usage

Differences

No significant differences in meaning or spelling. Both use the term identically within technical literature.

Connotations

None beyond the strict geological definition.

Frequency

Extremely low frequency in general discourse. Exclusively used in geological and related earth science contexts in both varieties.

Grammar

How to Use “metasomatism” in a Sentence

The [Rock Formation] underwent metasomatism.Metasomatism of the [Mineral Name] resulted in...[Fluid Type] caused metasomatism along the [Geological Feature].

Vocabulary

Collocations

strong
hydrothermal metasomatismcalc-silicate metasomatismpotassic metasomatismundergo metasomatismeffects of metasomatism
medium
widespread metasomatismintense metasomatismmetasomatism alteredmetasomatism associated with
weak
rock metasomatismsignificant metasomatismevidence of metasomatism

Examples

Examples of “metasomatism” in a Sentence

verb

British English

  • The granitic body was metasomatised by late-stage fluids.
  • These rocks have clearly been metasomatising over a long period.

American English

  • The granite was metasomatized by late-stage fluids.
  • These rocks have clearly been metasomatizing over a long period.

adverb

British English

  • The rock was metasomatically altered.
  • The minerals formed metasomatically.

American English

  • The rock was metasomatically altered.
  • The minerals formed metasomatically.

adjective

British English

  • The metasomatic alteration is clearly visible in thin section.
  • They identified a distinct metasomatic zone.

American English

  • The metasomatic alteration is clearly visible in thin section.
  • They identified a distinct metasomatic zone.

Usage

Meaning in Context

Business

Not used.

Academic

Core technical term in geology and petrology for describing rock-fluid interactions.

Everyday

Virtually never used.

Technical

Essential term for describing processes in ore genesis, metamorphic petrology, and geochemistry.

Vocabulary

Synonyms of “metasomatism”

Strong

metasomatosis

Neutral

hydrothermal alterationchemical alteration

Weak

rock alterationmineral replacement

Vocabulary

Antonyms of “metasomatism”

isochemical metamorphismstatic recrystallization

Watch out

Common Mistakes When Using “metasomatism”

  • Misspelling as 'metasomatosis' (though this is a rare synonym).
  • Confusing it with 'metamorphism'.
  • Using it outside of a geological/chemical replacement context.

FAQ

Frequently Asked Questions

Metamorphism changes a rock's mineralogy and texture primarily through heat and pressure, largely in a closed chemical system. Metasomatism specifically involves significant chemical exchange with an external fluid, adding or removing elements.

It is a common and geologically important process in specific settings, such as around igneous intrusions, in fault zones, and in areas of hydrothermal activity, often responsible for forming economic mineral deposits.

Sometimes. Effects like colour halos, distinct mineral banding, or the complete replacement of one mineral by another (e.g., serpentinisation) can be visible. However, detailed study usually requires a microscope or chemical analysis.

Rarely. It is occasionally borrowed as a metaphor in fields like materials science or biology to describe a process of transformative replacement, but its primary and almost exclusive domain is geology.

The chemical alteration of a rock by the addition or removal of elements through fluids.

Metasomatism is usually technical, academic (geology, petrology, mineralogy) in register.

Metasomatism: in British English it is pronounced /ˌmɛtəˈsəʊmətɪz(ə)m/, and in American English it is pronounced /ˌmɛdəˈsoʊməˌtɪzəm/. Tap the audio buttons above to hear it.

Learning

Memory Aids

Mnemonic

Think of META-SOAP-ism: imagine a rock being deeply cleaned and its minerals swapped out by a powerful, soapy (hydrothermal) fluid.

Conceptual Metaphor

A geological 'chemical recipe swap' where fluids act as a delivery and removal service for elements.

Practice

Quiz

Fill in the gap
The formation of the ore deposit was attributed to , where hydrothermal solutions altered the host rock's chemistry.
Multiple Choice

What is the primary driver of metasomatism?

metasomatism: meaning, definition, pronunciation and examples | Lingvocore