Journal ArticleDOI
Activity–composition relations for the calculation of partial melting equilibria in metabasic rocks
Eleanor C. R. Green,Richard White,Johann F.A. Diener,Roger Powell,Tim Holland,Richard M. Palin +5 more
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TLDR
In this paper, a set of thermodynamic models for partial melting equilibria for metabasic rocks is presented, consisting of new activity composition relations combined with end-member thermodynamic properties from the Holland & Powell dataset.Abstract:
A set of thermodynamic models is presented that, for the first time, allows partial melting equilibria to be calculated for metabasic rocks. The models consist of new activity–composition relations combined with end-member thermodynamic properties from the Holland & Powell dataset, version 6. They allow for forward modelling in the system Na (Formula presented.) O–CaO–K (Formula presented.) O–FeO–MgO–Al (Formula presented.) O (Formula presented.) –SiO (Formula presented.) –H (Formula presented.) O–TiO (Formula presented.) –Fe (Formula presented.) O (Formula presented.). In particular, new activity–composition relations are presented for silicate melt of broadly trondhjemitic–tonalitic composition, and for augitic clinopyroxene with Si–Al mixing on the tetrahedral sites, while existing activity–composition relations for hornblende are extended to include K (Formula presented.) O and TiO (Formula presented.). Calibration of the activity–composition relations was carried out with the aim of reproducing major experimental phase-in/phase-out boundaries that define the amphibolite–granulite transition, across a range of bulk compositions, at ≤13 kbar.read more
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Earth's first stable continents did not form by subduction
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Earth's first stable continents did not form by subduction
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Rhyolite-MELTS: A Modified Calibration of MELTS Optimized for Silica-Rich, Fluid-Bearing Magmatic Systems
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Secular change and the onset of plate tectonics on Earth
Richard M. Palin,M. Santosh,M. Santosh,Wentao Cao,Shan-Shan Li,David Hernández-Uribe,A. J. Parsons +6 more
TL;DR: A review of evidence for paleo-subduction preserved within the geological record, with a focus on metamorphic rocks and the geodynamic information that can be derived from them is provided in this paper.
Journal ArticleDOI
High-grade metamorphism and partial melting of basic and intermediate rocks
Richard M. Palin,Richard White,Eleanor C. R. Green,Johann F.A. Diener,Roger Powell,Tim Holland +5 more
TL;DR: In this paper, phase diagrams calculated in the Na2O−CaO−K2O-FeO-MgO-Al2O3−SiO2-H2O•TiO2−O2 (NCKFMASHTO) compositional system for a range of natural basic and intermediate bulk compositions for conditions of 2-12kbar and 600-1050 ǫ c using newly parameterized activity-composition relationships detailed in a companion paper by Green et al.
References
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Journal ArticleDOI
An internally consistent thermodynamic data set for phases of petrological interest
TL;DR: In this paper, the thermodynamic properties of 154 mineral endmembers, 13 silicate liquid end-members and 22 aqueous fluid species are presented in a revised and updated data set.
Journal ArticleDOI
Dehydration melting of metabasalt at 8-32 kbar : Implications for continental growth and crust-mantle recycling
Robert P. Rapp,E. Bruce Watson +1 more
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Chemical mass transfer in magmatic processes IV. A revised and internally consistent thermodynamic model for the interpolation and extrapolation of liquid-solid equilibria in magmatic systems at elevated temperatures and pressures
Mark S. Ghiorso,Richard O. Sack +1 more
TL;DR: In this article, a regular solution-type thermodynamic model for twelve-component silicate liquids in the system SiO2-TiO 2-Al 2O3-Fe2O 3-Cr2O3 -FeO-MgO-CaO-Na2O-K 2O-P2O5-H2O is calibrated.
Journal ArticleDOI
Internally-Consistent Thermodynamic Data for Minerals in the System Na2O-K2O-CaO-MgO-FeO-Fe2O3-Al2O3-SiO2-TiO2-H2O-CO2
Journal ArticleDOI
A general equation for estimating Fe3+ concentrations in ferromagnesian silicates and oxides from microprobe analyses, using stoichiometric criteria
TL;DR: In this article, a simple general equation is presented for estimating the Fe 3 § concentrations in ferromagnesian oxide and silicate minerals from microprobe analyses, assuming that iron is the only element present with variable valency.
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