Video Experimental Relacionado
Updated: May 16, 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
Evidencia de un dínamo en el grupo principal de pallacita cuerpo madre
John A Tarduno1, Rory D Cottrell, Francis Nimmo
1Department of Earth and Environmental Sciences, University of Rochester, Rochester, NY 14627, USA. john.tarduno@rochester.edu
Resumen
Los meteoritos de pallasita se formaron cuando el núcleo del impactador inyectó metal líquido en un protoplaneta.
Área de la Ciencia:
- Ciencias planetarias Ciencias planetarias.
- Cosmoquímica es la cosmoquímica.
- La geofísica es la geofísica.
Sus antecedentes:
- Las pallasitas son meteoritos de piedra y hierro compuestos de cristales de olivino y metal de hierro y níquel.
- Su origen de formación ha permanecido un enigma de larga data en la investigación de meteoritos.
Objetivo del estudio:
- Para investigar el origen de los meteoritos de pallacita.
- Comprender las condiciones y procesos involucrados en su formación.
Principales métodos:
- Análisis de pequeñas inclusiones magnéticas dentro de las olivinas de pallasita.
- Mediciones de paleointensidad para determinar la intensidad del campo magnético.
- Modelado térmico de cuerpos protoplanetarios.
Principales resultados:
- Las olivinas de pallacita contienen inclusiones magnéticas con excelentes propiedades de grabación.
- Los datos paleomagnéticos revelan fuertes campos magnéticos, indicativos de la acción de la dínamo.
- El modelo de formación sugiere la inyección de metal líquido en el manto de un protoplaneta.
Conclusiones:
- Las pallasitas probablemente se formaron a partir de la inyección de hierro-níquel líquido del núcleo de un impactador en el manto poco profundo de un protoplaneta.
- El protoplaneta se mantuvo intacto durante millones de años después del impacto, lo que permitió la formación de pallacita.
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