Basalt evolution at low pressure: implications from an experimental study in the system CaO-FeO-MgO-Al2O3-SiO2
Article Abstract:
The evolution of basalts at atmospheric pressure was investigated in experiments performed on the low-temperature fields of liquid + anorthite + augite + olivine (liq + an + aug + ol) assemblages. Together with a previous work on high-temperature fields, the divariant field of liq + an + aug + ol can be contoured and some of its boundaries demarcated. The boundary of the liq + an + aug + ol assemblage is composed of six segments with one additional phase. The stability of the assemblage and the composition of phases are dependent on temperature and the silica content of the melt.
Publication Name: Contributions to Mineralogy and Petrology
Subject: Earth sciences
ISSN: 0010-7999
Year: 1992
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The influence of crystallography and kinetics on phengite breakdown reactions in a low-pressure metamorphic aureole
Article Abstract:
Phengitic muscovites undergoing thermal decomposition due to contact with a metamorphic aureole at low-pressure were examined using transmission electron microscopy to study the various aspects of the breakdown process. Partial breakdown of muscovites yields a combination of cordierite, spinel, sillimanite, mullite, potassium-feldspar, biotite and phengite. Various regions within individual phengite grains undergoing partial decomposition show gradation in reaction and different end-products.
Publication Name: Contributions to Mineralogy and Petrology
Subject: Earth sciences
ISSN: 0010-7999
Year: 1992
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Experimental and thermodynamic study of heterogeneous and homogeneous equilibria in the system NaAlSiO4-SiO2
Article Abstract:
A thermodynamic dataset is obtained for the phases nepheline, jadeite, alpha-quartz, albite and monalbite by considering two reversed heterogeneous reactions of the rock-forming minerals in the system NaAlSiO4-SiO2. The refined dataset along with their uncertainties and correlation are used to form the NaAlSiO4-SiO2 phase diagram involving 2-sigma confidence interval for each P-T curve.
Publication Name: Contributions to Mineralogy and Petrology
Subject: Earth sciences
ISSN: 0010-7999
Year: 1995
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- Abstracts: High-grade metamorphism, dehydration and crustal melting: A reinvestigation base don new experiments in the silica-saturated portion of the system KAIOsub2-MgO-SiOsub2-Hsub2O-Cosub2 at P< 1.5 GPa
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- Abstracts: Evolution of metamorphic volatiles during exhumation of microdiamond-bearing granulites in the Western Gneiss Region, Norway
- Abstracts: Compositional variation and primary water contents of differentiated interstitial and included glasses in boninites
- Abstracts: The system O-S-Fe at 1 bar. Geochemistry of Tertiary tholeiites and picrites from Qeqertarssuaq (Disko Island) and Nuussuaq, West Greenland with implications for the mineral potential of comagmatic intrusions