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Response to a comment by Chun-Ming Wu on “Quantifying the tectono-metamorphic evolution of pelitic rocks from a wide range of tectonic settings: mineral compositions in equilibrium”

  • Mark J. CaddickEmail author
  • Alan B. Thompson
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Wu (2009) has commented on aspects of our paper (Caddick and Thompson 2008; hereafter CT08), whose primary purpose was to demonstrate how the coexisting compositions of minerals are highly sensitive to the available buffering assemblage in metamorphic rocks over wide ranges of pressure and temperature (P and T). The concerns of Wu involve (a) the validity of methods used to derive expressions for garnet–biotite (GB) and garnet–plagioclase (GASP) equilibria as a function of P and T, and (b) the performance of these expressions compared to alternative thermobarometer calibrations. In particular, calculation from a large thermodynamic dataset (Holland and Powell 1998) rather than a primary set of reversed equilibrium experiments, and the use of PTXPhase relations calculated for a fixed bulk-rock composition are questioned.

CT08 examines the P and Tdependence of particular exchange equilibria and net transfer (continuous) reactions using existing calibrations via published...

Keywords

Mineral Composition Kyanite Natural Assemblage Calculate Phase Equilibrium Wide Compositional Range 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

References

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Copyright information

© Springer-Verlag 2009

Authors and Affiliations

  1. 1.Institute of Mineralogy and PetrologyZurichSwitzerland

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