Dissolution rates of actinolite and chlorite from a whole-rock experimental study of metabasalt dissolution from 2≤pH≤12 at 25°C

T. Critelli, L. Marini, J. Schott, V. Mavromatis, C. Apollaro*, T. Rinder, R. De Rosa, E. H. Oelkers

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

Abstract

The dissolution rates of the minerals actinolite and chlorite were determined from metabasalt element release rates measured at 25°C and 2<pH<12 in mixed flow reactors. At pH 2.0 and 3.2, chlorite rates are 3 and 5 times faster, respectively, than corresponding actinolite rates, whereas the Si release rates from metabasalt are intermediate between chlorite and actinolite rates. In contrast, at pH 7.2 and 12.0, chlorite, actinolite and the metabasalt release Si at the same rates within analytical uncertainties. At pH 6.3, it was only possible to obtain the chlorite dissolution rate; at this pH the measured chlorite dissolution rate is 10-11.86mol/m2/s. Mineral dissolution rates obtained in this study are within the range of corresponding values reported in the literature. This observation suggests that the dissolution rates of major-constituent minerals in a multi-phase rock are not affected by the presence of the other minerals. This conclusion validates the common assumption that the dissolution rate of an individual mineral is equal to that of the same mineral in a dissolving multi-mineralogic rock, at least for major constituents.

Original languageEnglish
Pages (from-to)100-108
Number of pages9
JournalChemical Geology
Volume390
DOIs
Publication statusPublished - 8 Dec 2014

Keywords

  • Actinolite
  • Chlorite
  • Dissolution rates
  • Metabasalt
  • Whole-rock dissolution

ASJC Scopus subject areas

  • Geology
  • Geochemistry and Petrology

Fields of Expertise

  • Sonstiges

Treatment code (Nähere Zuordnung)

  • Basic - Fundamental (Grundlagenforschung)
  • Application
  • Experimental

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