Diffusion in silicate melts: I. Self diffusion in CaO-Al{sub 2}O{sub 3}-SiO{sub 2} at 1500{degrees}C and 1 GPa

Journal Article · Fri Nov 01 04:00:00 EST 1996 · Geochimica et Cosmochimica Acta

DOI:https://doi.org/10.1016/S0016-7037(96)00288-8· OSTI ID:543147

Liang, Yan ^[1]; Richter, F M; Davis, A M ^[2]

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1. Univ. of Chicago, IL (United States)
2. Univ. of Chicago, IL (United States); and others

Self diffusion coefficients of calcium (D{sub Ca}), aluminum (D{sub A1}), silicon (D{sub Si}), and oxygen (D{sub o}) were measured in molten CaO-Al{sub 2}O{sub 3}-SiO{sub 2} at 1500{degrees}C and 1 GPa over a range of melt compositions, using the isotope tracer method. For all but one composition, the measured self diffusion coefficients decrease in the order D{sub Ca} > D{sub Al} > D{sub o} > D{sub Si}, with D{sub Ca} {approximately} 4-19D{sub Si}, D{sub Al}, {approximately} 2D{sub Si}, and D{sub o} {approximately} 1-2D{sub Si}. The relative uncertainties, based on replicated experiments, are 8% for D{sub Ca}, 27% for D{sub Al}, 28% for D{sub Si}, and 18% for D{sub o}. Although the self diffusion coefficients of calcium, aluminum, silicon, and oxygen increase with the decrease of melt viscosity, they do not obey the Stokes-Einstein equation or the Eyring equation. 69 refs., 6 figs., 6 tabs.

• DOE Contract Number: FG02-94ER14478
• OSTI ID: 543147
• Journal Information: Geochimica et Cosmochimica Acta, Journal Name: Geochimica et Cosmochimica Acta Journal Issue: 22 Vol. 60; ISSN 0016-7037; ISSN GCACAK
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
58 GEOSCIENCES
CHEMICAL COMPOSITION
DIFFUSION
GEOCHEMISTRY
MAGMA
MATERIALS TESTING
SILICATE MINERALS