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Marte: un nuevo régimen de cristalización del núcleo
Andrew J Stewart1, Max W Schmidt, Wim van Westrenen
1Institute for Mineralogy and Petrology, Eidgenössische Technische Hochschule Zurich, CH 8092 Zurich, Switzerland.
Science (New York, N.Y.)
|June 2, 2007
Resumen
El núcleo de Marte es líquido y carece de un núcleo interno rico en hierro como el de la Tierra. El enfriamiento planetario puede causar la cristalización a través de un modelo de "núcleo de nieve" o "núcleo interno de sulfuro".
Área de la Ciencia:
- Ciencias planetarias Ciencias planetarias.
- La geofísica es la geofísica.
- La geoquímica de la tierra sólida La geoquímica de la tierra sólida
Sus antecedentes:
- La evolución del núcleo marciano a menudo se compara con la de la Tierra.
- Los modelos anteriores asumieron estructuras centrales y caminos evolutivos similares.
Objetivo del estudio:
- Para investigar el estado físico y el comportamiento de cristalización del núcleo marciano.
- Para determinar si Marte desarrolla un núcleo interno rico en hierro.
Principales métodos:
- Experimentos de alta presión y alta temperatura en sistemas de hierro-azufre y hierro-níquel-azufre.
- Simulaciones en presiones representativas del núcleo de Marte.
Principales resultados:
- El núcleo marciano es actualmente completamente líquido.
- Los datos experimentales sugieren que Marte no formará un núcleo interno rico en hierro.
- Se predice que la cristalización seguirá un modelo de "núcleo de nieve" o de "núcleo interno de sulfuro".
Conclusiones:
- La evolución del núcleo marciano diverge de la de la Tierra.
- La futura cristalización del núcleo en Marte diferirá significativamente de la de la Tierra.
- Se necesitan nuevos modelos para explicar la dinámica del núcleo marciano.
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