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La estructura química del penacho del manto hawaiano
Zhong-Yuan Ren1, Stephanie Ingle, Eiichi Takahashi
1Department of Earth and Planetary Sciences, Tokyo Institute of Technology 2-12-1 Ookayama, Meguro-ku, 152-8551, Japan. zyren@jamstec.go.jp
Nature
|August 16, 2005
Resumen
La cadena volcánica del emperador hawaiano.
Área de la Ciencia:
- La geoquímica es la geoquímica.
- Volcanología Volcanología.
- La geofísica es la geofísica.
Sus antecedentes:
- La cadena volcánica Hawaiian-Emperor está vinculada a una pluma profunda del manto.
- Los volcanes exhiben variaciones geoquímicas, lo que sugiere fuentes de manto zonadas.
- Las inclusiones de fusión ofrecen información sobre las complejidades de la fuente del manto.
Objetivo del estudio:
- Para investigar la estructura de composición de la pluma del manto hawaiano.
- Para determinar si el penacho tiene zonas concéntricas.
- Para entender la fuente de las variaciones geoquímicas en las lavas hawaianas.
Principales métodos:
- Análisis de las composiciones de elementos principales y oligoelementos.
- Examen de las inclusiones de fundición alojadas en olivino.
- Estudio de la etapa de escudo de los volcanes hawaianos.
Principales resultados:
- Tanto las firmas geoquímicas 'Kea' como 'Loa' se encuentran en inclusiones de fusión dentro de volcanes individuales.
- Presencia constante de dos componentes de la fuente del manto en todas las lavas analizadas.
- Variaciones geoquímicas observadas en muestras de una sola roca.
Conclusiones:
- Es poco probable que la pluma del manto hawaiano esté compuesta por zonas concéntricas.
- Es probable que las variaciones químicas observadas estén controladas por la estructura térmica de la pluma.
- Un solo componente de la fuente del manto puede dominar los flujos de lava individuales, pero siempre están presentes múltiples componentes.
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