气候变化领域集成服务门户(CCPortal): Density of hydrous carbonate melts under pressure, compressibility of volatiles and implications for carbonate melt mobility in the upper mantle

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DOI	10.1016/j.epsl.2019.116043
	Density of hydrous carbonate melts under pressure, compressibility of volatiles and implications for carbonate melt mobility in the upper mantle
	Ritter X.; Sanchez-Valle C.; Sator N.; Desmaele E.; Guignot N.; King A.; Kupenko I.; Berndt J.; Guillot B.
发表日期	2020
ISSN	0012821X
卷号	533
英文摘要	Knowledge of the effect of water on the density of carbonate melts is fundamental to constrain their mobility in the Earth's interior and the exchanges of carbon between deep and surficial reservoirs. Here we determine the density of hydrous MgCO3 and CaMg(CO3)2 melts (10 wt% H2O) from 1.09 to 2.98 GPa and 1111 to 1763 K by the X-ray absorption method in a Paris-Edinburgh press and report the first equations of state for hydrous carbonate melts at high pressure. Densities range from 2.26(3) to 2.50(3) g/cm3 and from 2.34(3) to 2.48(3) g/cm3 for hydrous MgCO3 and CaMg(CO3)2 melts, respectively. Combining the results with density data for the dry counterparts from classical Molecular Dynamic (MD) simulations, we derive the partial molar volume (V‾H2O, V‾CO2) and compressibility of H2O and CO2 components at crustal and upper mantle conditions. Our results show that V‾CO2 in alkaline carbonate melts is larger and less compressible than V‾H2O at the investigated conditions. Neither the compressibility nor V‾H2O depend on carbonate melt composition within uncertainties, but they are larger than those in silicate melts at crustal conditions. V‾H2O in alkaline earth carbonate melts decreases from 25(1) to 16.5(5) cm3/mol between 0.5 and 4 GPa at 1500 K. Contrastingly, comparison of our results with literature data suggests strong compositional effects on V‾CO2, that is also less compressible than in transitional melts (e.g., kimberlites) and carbonated basalts. We further quantify the effect of hydration on the mobility of carbonate melts in the upper mantle and demonstrate that 10 wt% H2O increases the mobility of MgCO3 melts from 37 to 67 g.cm−3.Pa−1s−1 at 120 km depth. These results suggest efficient carbonate melt extraction during partial melting and fast migration of incipient melts in the shallow upper mantle. © 2019 Elsevier B.V.
关键词	compressibility of volatiles density equation of state hydrous carbonate melts melt mobility
英文关键词	Calcium compounds; Carbon dioxide; Compressibility; Density (specific gravity); Equations of state; Magnesite; Molecular dynamics; Silicates; X ray absorption; Alkaline carbonates; Carbonate melts; Classical molecular dynamics; Compositional effects; Earth's interior; Effect of water; Equation of state; Partial Molar volume; Carbonation; carbonate rock; compressibility; computer simulation; hydrous mineral; numerical model; partial melting; pressure gradient; upper mantle; volatile substance; XANES spectroscopy
语种	英语
来源期刊	Earth and Planetary Science Letters
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/202860
作者单位	Institut für Mineralogie, Westfälische Wilhelms-Universität Münster, Münster, 48149, Germany; Sorbonne Université, CNRS, Laboratoire de Physique Théorique de la Matière Condensée, LPTMC, Paris, F-75005, France; Synchrotron SOLEIL, St Aubin, 91192, France
推荐引用方式 GB/T 7714	Ritter X.,Sanchez-Valle C.,Sator N.,et al. Density of hydrous carbonate melts under pressure, compressibility of volatiles and implications for carbonate melt mobility in the upper mantle[J],2020,533.
APA	Ritter X..,Sanchez-Valle C..,Sator N..,Desmaele E..,Guignot N..,...&Guillot B..(2020).Density of hydrous carbonate melts under pressure, compressibility of volatiles and implications for carbonate melt mobility in the upper mantle.Earth and Planetary Science Letters,533.
MLA	Ritter X.,et al."Density of hydrous carbonate melts under pressure, compressibility of volatiles and implications for carbonate melt mobility in the upper mantle".Earth and Planetary Science Letters 533(2020).