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Updated: Jul 12, 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
El silicio en el metal de condrita carbonácea: reliquia de la condensación a alta temperatura
Science (New York, N.Y.)
|October 26, 1979
Resumen
Los grandes granos de metal en el meteorito Murchison contienen silicio. Esto sugiere aleaciones condensadas del gas de la nebulosa solar a presiones y temperaturas específicas, sin volver a equilibrar.
Área de la Ciencia:
- Cosmoquímica es la cosmoquímica.
- Ciencias planetarias Ciencias planetarias.
- Ciencia de los materiales Ciencia de los materiales.
Sus antecedentes:
- Las condritas carbonáceas, como el meteorito Murchison, son materiales primitivos del sistema solar.
- Los granos de metal dentro de los meteoritos proporcionan información sobre las primeras condiciones del sistema solar.
- Comprender la composición de estos granos ayuda a reconstruir los procesos nebulosos.
Objetivo del estudio:
- Para analizar la composición de un grano de metal excepcionalmente grande del meteorito Murchison.
- Para investigar las condiciones bajo las cuales tales aleaciones metálicas podrían formarse en la nebulosa solar temprana.
- Para determinar el papel del equilibrio en la formación de grano de metal.
Principales métodos:
- El análisis de microsondas electrónicas (EMPA) se utilizó para determinar la composición elemental del grano de metal.
- Se realizaron cálculos termodinámicos para modelar la condensación de la aleación.
- El estudio consideró varias presiones y temperaturas relevantes para la nebulosa solar.
Principales resultados:
- El grano de metal analizado contenía 0.24 mol por ciento de silicio.
- Los modelos termodinámicos indican que este contenido de silicio es consistente con la condensación del gas de la nebulosa solar.
- Las presiones de formación se calcularon entre 10^-5 y 10^-3 atmósferas.
- Los resultados implican una falta de equilibrio post-condensación con el gas circundante por debajo de 1200 Kelvin.
Conclusiones:
- La presencia de silicio en el grano de metal es un resultado natural de la condensación nebular bajo condiciones específicas.
- Los hallazgos apoyan los modelos de formación de aleaciones en el sistema solar temprano.
- El estudio destaca la importancia de los procesos de no equilibrio en la preservación de las composiciones nebulosas primarias.
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