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Implicaciones para la dinámica del manto de la alta temperatura de fusión de la perovskita
Science (New York, N.Y.)
|June 3, 1994
Resumen
El manto inferior es el manto inferior.
Área de la Ciencia:
- La geofísica es la geofísica.
- Física de los minerales Física de los minerales
Sus antecedentes:
- El manto inferior, una región clave en la geodinámica de la Tierra, está dominado por (Mg, Fe) SiO3-perovskita.
- Investigaciones recientes sugieren que esta fase mineral posee una alta temperatura de fusión.
Objetivo del estudio:
- Para investigar las implicaciones de las altas temperaturas de fusión de la perovskita en la dinámica del manto inferior.
- Para modelar la convección del manto bajo estas condiciones.
Principales métodos:
- Se emplearon modelos de convección numérica.
- Las simulaciones exploraron varios números de Rayleigh y tasas de calentamiento interno.
Principales resultados:
- Las bajas temperaturas homólogas (0,3-0,5) se encontraron consistentemente en el manto inferior modelado.
- El deslizamiento dúctil de alta temperatura es factible incluso a estas temperaturas más bajas.
- Los modelos con bajo calentamiento interno produjeron máximos de viscosidad en el manto inferior medio, consistente con las observaciones geofísicas.
Conclusiones:
- Las altas temperaturas de fusión de la perovskita conducen a un manto inferior dinámicamente "frío".
- Este estado "frío" permite el deslizamiento a altas temperaturas y explica las variaciones de viscosidad observadas.
- Los hallazgos concilian la física mineral con la convección del manto a gran escala y los datos del geoide.
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