Journal ArticleDOI
The Granite System at Pressures of 4 to 10 Kilobars
TLDR
In this paper, phase relations in a portion of the granite system, KAlSi3O8-NaAlSi 3O8 NaAlSi8-SiO2-H2O have been studied in the pressure range 4 to 10 kb, where melting begins at 625°C at an isobaric invariant point involving albite + orthoclase + quartz + liquid + vapor.Abstract:
Phase relations in a portion of the granite system, KAlSi3O8-NaAlSi3O8-SiO2-H2O have been studied in the pressure range 4 to 10 kb. At 10 kb, melting begins at 625°C at an isobaric invariant point involving albite + orthoclase + quartz + liquid + vapor. The anhydrous composition of the liquid at this isobaric quaternary eutectic corresponds to 21 orthoclase: 56 albite: 23 quartz in contrast to that at the isobaric quaternary minimum at 0.5 kb, where the liquid corresponds to 31 orthoclase: 30 albite: 39 quartz. This represents a shift of the liquid, in anhydrous projection, almost directly toward NaAlSi with increasing P. The quaternary minimum in this system becomes a eutectic at approximately 3.6 kb. Compositional comparisons among granites, aplites, zoned pegmatites, and the quaternary minimum and eutectic suggest that igneous pegmatites and aplites represent magmas that were saturated or nearly saturated with water when they began to crystallize. Trends in bulk composition among pegmatites further suggest selective losses of alkalies during crystallization, probably by diffusion through aqueous fluids coexisting with the silicate melts and their solid products.read more
Citations
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Journal ArticleDOI
Gradients in silicic magma chambers: Implications for lithospheric magmatism
TL;DR: In this article, the authors studied the effect of pre-emptive and preemptive gradients in T and O 2 in a variety of compositionally zoned ash flow tuffs.
Journal ArticleDOI
Experimental determination of the fluid-absent melting relations in the pelitic system
Daniel Vielzeuf,John R. Holloway +1 more
TL;DR: In this article, the melting of a natural metapelite under fluid-absent conditions was studied experimentally and a series of P-T, T-XH2O, and liquidus diagrams were proposed.
Journal ArticleDOI
Oxygen isotopic fractionation in the system quartz-albite-anorthite-water
TL;DR: Oxygen isotopic fractionations have been determined between quartz and water, albite and water and anorthite and water at temperatures from 300 to 825°C, and pressures from 15 to 25 kbar as mentioned in this paper.
Journal ArticleDOI
Constraints on melting and magma production in the crust
John D. Clemens,Daniel Vielzeuf +1 more
TL;DR: In this article, the authors present a model for calculating the amounts of melt that may be formed by fluid-absent breakdown of micas and amphiboles in common crustal rock types (pelitic, quartzofeldspathic, intermediate and mafic).
Book
Principles of igneous and metamorphic petrology
Anthony R. Philpotts,Jay J. Ague +1 more
TL;DR: The authors provides a basic understanding of the formative processes of igneous and metamorphic rock through quantitative applications of simple physical and chemical principles, and encourages a deeper comprehension of the subject by explaining the petrologic principles.
References
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Book ChapterDOI
ORIGIN OF GRANITE IN THE LIGHT OF EXPERIMENTAL STUDIES IN THE SYSTEM NaAlSi3O8–KAlSi3O8–SiO2–H2O
O. F. Tuttle,N. L. Bowen +1 more
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.
Journal ArticleDOI
The upper three-phase region in the system SiO 2 -H 2 O
TL;DR: In this paper, a quadruple point for the equilibrium among tridymite, 2 fluids, and cristobalite is estimated to be near 1470° C and 400 bars.
Journal ArticleDOI
A method for determining the solubility of water in silicate melts
C. W. Burnham,R. H. Jahns +1 more
TL;DR: The method described in this paper for determining the solubility of water in silicate melts consists primarily of locating the boundary (or projected boundary) between the field of liquid and the fields of liquid+gas in successive isobaric T-X H2O sections for a given system.
Journal ArticleDOI
The System $NaAlSi_{3}O_{8}-KAlSi_{3}O_{8}-H_{2}O$
N. L. Bowen,O. F. Tuttle +1 more
TL;DR: In the presence of water vapor under pressure, soda and potash feldspar crystallize readily from their glasses as discussed by the authors and form a complete series of solid solutions showing continuous variation of lattice-spacing as measured by X-rays.