metasomatizing

Verb

metasomatize (third-person singular simple present metasomatizes, present participle metasomatizing, simple past and past participle metasomatized)

1. (transitive) To change the bulk chemical composition of a rock is by the introduction of components from an external source, especially by a hydrothermal fluid.
   • In some way, not clearly understood, hydrothermal action metasomatizes the original andesite without destroying original textures or changing volumes.1999, James W. Vallance, Postglacial lahars and potential hazards in the White Salmon River system on the Southwest Flank of Mound Adams, Washington