The alteration of olivine in basaltic and associated lavas - Part II: Intermediate and low temperature alteration Article

Baker, I, Haggerty, SE. (1967). The alteration of olivine in basaltic and associated lavas - Part II: Intermediate and low temperature alteration . CONTRIBUTIONS TO MINERALOGY AND PETROLOGY, 16(3), 258-273. 10.1007/BF00371095

cited authors

  • Baker, I; Haggerty, SE

authors

abstract

  • Olivines which cool under oxidizing conditions exsolve iron oxides at high temperature, and at low temperatures break down to essentially chloritic materials. Olivines which cool under non-oxidizing conditions alter at intermediate temperatures to complex assemblages of chlorite and interstratified phyllosilicates containing a smectite. Alteration under oxidizing conditions at low temperature, probably below 140° C, produces "iddingsite", an orientated assemblage of goethite and interstratified phyllosilicates also containing a smectite. Post-deuteric alteration extends or initiates the breakdown of olivine to phyllosilicate mixtures often resulting in widespread movement of materials through the flow. Post-deuteric alteration of "iddingsite" produces strongly pleochroic, highly ordered varieties which eventually break down to green phyllosilicate assemblages. Weathering of olivine may produce orientated assemblages similar to deuteric forms of "iddingsite". Weathering of green alteration products results in oxidation and the liberation of discrete iron hydroxides. Alteration in all cases requires exchange of material between interstitial components and olivine. During deuteric alteration, plagioclase and pyroxene are usually unaffected. © 1967 Springer-Verlag.

publication date

  • October 1, 1967

published in

Digital Object Identifier (DOI)

start page

  • 258

end page

  • 273

volume

  • 16

issue

  • 3