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Updated: May 24, 2026
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Metal-silicate Partitioning at High Pressure and Temperature: Experimental Methods and a Protocol to Suppress Highly Siderophile Element Inclusions
Published on: June 13, 2015
Isotope fractionation by thermal diffusion in silicate melts.
Daniel J Lacks1, Gaurav Goel, Charles J Bopp
1Department of Chemical Engineering, Case Western Reserve University, Cleveland, Ohio 44106, USA.
Physical Review Letters
|March 10, 2012
Summary
Isotope fractionation in thermal gradients is explained by classical mechanics in silicate melts. Network formers like silicon and oxygen show less fractionation than network modifiers, as predicted by a new scaling relation.
Area of Science:
- Geochemistry
- Physical Chemistry
- Materials Science
Background:
- Isotope fractionation in thermal gradients is poorly understood in complex fluids.
- Silicate melts are complex fluids relevant to geological and materials science.
Purpose of the Study:
- To quantitatively understand isotope fractionation in silicate melts under thermal gradients.
- To develop a predictive model for isotope fractionation in complex fluids.
Main Methods:
- Experiments on silicate melts.
- Molecular dynamics simulations.
- Scaling analysis based on Chapman-Enskog theory.
Main Results:
- Isotope fractionation is driven by classical mechanical effects.
- A scaling relation based on Chapman-Enskog theory accurately predicts fractionation.
- Network-forming elements (Si, O) exhibit less fractionation than network modifiers (Mg, Ca, Fe, Sr, Hf, U).
Conclusions:
- Classical mechanics governs isotope fractionation in thermal gradients within silicate melts.
- The developed scaling relation provides a parameter-free prediction for isotope fractionation.
- Understanding these fractionation patterns is crucial for geochemistry and materials science.
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