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metasomatism Line breaks: meta|soma¦tism
Pronunciation: /ˌmɛtəˈsəʊmətɪz(ə)m/

Definition of metasomatism in English:


[mass noun] Geology
Change in the composition of a rock as a result of the introduction or removal of chemical constituents.
Example sentences
  • In the cooler middle and upper crust, felsic magmatism and aqueous metasomatism are most important.
  • Textural relationships and geological context need to be determined to distinguish these burial-related phases from monazites ascribed to granite metasomatism or low-grade metamorphism.
  • Much more commonly, however, metasomatism involves chemical exchange with fluids; in the earth's crust these fluids are usually aqueous solutions.


Pronunciation: /ˌmɛtəsəʊˈmɑtɪk/
Example sentences
  • Specifically, gangue formed by both metasomatic alteration and precipitation during ore formation can yield a wealth of information about the origins and physical conditions of the ore-forming fluids.
  • Dolerite dykes that cut the peridotite show chilled margins and local metasomatic calcic alteration.
  • Jadeite dykes are intruded within serpentinites and are the metasomatic products of crystallization from hydrous fluids reacting with the serpentinites.
(also metasomatise) verb
Example sentences
  • Most recent studies of potassic magma generation ascribe such characteristics to metasomatized portions of the subcontinental lithosphere.
  • When metamorphism is accompanied by a change in the chemistry of a rock, the rock is said to have been metasomatized.
  • These fluids altered and metasomatized the previously emplaced volcanic products (lavas, pyroclasts).


Late 19th century: from meta- (expressing change) + Greek sōma, somat- 'body' + -ism.

Definition of metasomatism in:
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