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Plagioclase-alkali-feldspar geothermometry revisited

Published online by Cambridge University Press:  05 July 2018

Marjorie Powell
Affiliation:
Department of Earth Sciences, University of Leeds, Leeds LS2 9JT
Roger Powell
Affiliation:
Department of Earth Sciences, University of Leeds, Leeds LS2 9JT

Summary

The plagioclase-alkali-feldspar geothermometer formulated by Stormer (1975) does not take into account the effect of small amounts of calcium in the alkali feldspar. This geothermometer has been reformulated using ternary regular solution model equations, and it is shown that as the Ca content of the alkali feldspar increases the temperature calculated using the Stormer geothermometer will be increasingly too high.

Type
Research Article
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1977

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