Journal ArticleDOI
Calculation of Muscovite-Paragonite-Alkali Feldspar Phase Relations
TLDR
In this article, a projected binary phase diagram for the white mica dehydration is presented, where subsolidus univariant curves intersect H2O-saturated minimum-melting curves.Abstract:
Experimental data on K-Na exchange between NaCl-KCl-H2O fluids and alkali feldspars or white micas, and end-member dehydration reactions of white mica (± quartz to alkali feldspar plus corundum (or Al2SiO5) and H2O have been used to evaluate K-Na exchange potentials between coexisting white mica and alkali feldspar. Calculations using these exchange potentials and Margules parameters for excess molar Gibbs energies of alkali feld-spars and white micas have permitted the construction of a projected binary phase diagram for the white mica dehydration. Extrapolation to higher temperatures and pressures gives a topology wholly consistent with field evidence. The subsolidus univariant curves intersect H2O-saturated minimum-melting curves. At pressures greater than about 6 kbar the common assemblage Ms+Or+Ab+Q could undergo H2O-saturated minimum-melting at lower temperatures than the disappearance of paragonite or the kyanite-sillimanite isograd in more aluminous rocks. The apparent restriction of anatexis to rocks above the second sillimanite isograd may imply that activity of H2O is usually less than unity in high-grade regional metamorphism.read more
Citations
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Journal ArticleDOI
Fe-Mg cordierite stability in high-grade pelitic rocks based on experimental, theoretical, and natural observations
M. J. Holdaway,Sang Man Lee +1 more
TL;DR: In this paper, a P-X diagram for the Fe-Mg analogue of this reaction at 675 ° C is consistent with a naturally occuring cordierite-biotite K====== D ≥ 0.53 if Al content of biotite and cordierites water of hydration are taken into account.
Journal ArticleDOI
Crustal anatexis: An experimental review
TL;DR: A review of the phase relationships in the rock series gabbro-tonalite, granodiorite, and granite to 15 kbar is used as a basis for interpreting anatexis of deep crustal rocks including metamorphosed grey wackes and pelitic rocks as mentioned in this paper.
Journal Article
Composition of plutonic muscovite; genetic implications
TL;DR: In this paper, the authors used a set of 4l samples from 16 plutons in North America and Europe to evaluate the paragenesis of muscovite in igneous rocks.
Journal ArticleDOI
The current status of thermobarometry in metamorphic rocks
TL;DR: A recent survey of the literature on thermobarometry of individual metamorphic facies reveals the range of P-T encountered in each facies as discussed by the authors, showing that the blueschist, amphibolite and granulite facies give way to the eclogite faces over the pressure range of 12-16 kbar.
Journal ArticleDOI
An experimental study of the effect of boron on a water saturated haplogranite at 1 Kbar vapour pressure
TL;DR: In this paper, an experimental study of the effect of boron in the water saturated Q-Or-Ab-B2O3-H2O system has been performed at P = 1 Kbar to provide experimental data and explain the role of bboron in some late magmatic and early hydrothermal events.
References
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Journal ArticleDOI
Stability of andalusite and the aluminum silicate phase diagram
TL;DR: In this article, the effects of Si-Al disorder, fibrolite and sample preparation, comparison with previous data, geothermal gradient implications, and comparison of previous data were discussed.
ReportDOI
Thermodynamic properties of minerals and related substances at 298.15 K (25.0 C) and one atmosphere (1.013 bars) pressure and at higher temperatures
TL;DR: A detailed summary of the available thermodynamic data for minerals and related substances in a convenient form for the use of earth scientists can be found in this article, where the authors present a set of tables for high-temperature thermodynamic properties.
Journal ArticleDOI
Experimental determination of kyanite-andalusite and andalusite-sillimanite equilibria; the aluminum silicate triple point
Journal ArticleDOI
Alkali ion exchange between vapor and feldspar phases
TL;DR: In this article, an invariant 3-phase assemblage consisting of 2 alkali feldspars and an alkali chloride solution was investigated at temperatures of 350 degrees to 700 degrees C. at a pressure of 2000 atmospheres.