Effect of variable carbonate concentration on the solidus of mantle peridotite

  title={Effect of variable carbonate concentration on the solidus of mantle peridotite},
  author={Rajdeep Dasgupta and Marc M. Hirschmann},
  journal={American Mineralogist},
  pages={370 - 379}
Abstract To explore the effect of variable CO2 concentrations on the solidus of natural carbonated peridotite, we determined near-solidus phase relations of three different nominally anhydrous, carbonated lherzolite bulk compositions at 6.6 GPa. Starting mixes (PERC, PERC2, and PERC3) were prepared by adding variable proportions of a carbonate mixture that has the same Ca:Mg:Fe:Na:K ratio as the base silicate peridotite [MixKLB-1: Mg no. = 89.7; Ca no. = molar Ca/(Ca + Mg + Fe*) = 0.05]. For… 

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