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Updated: Jul 12, 2026

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Published on: August 5, 2016
Bloque levantado del manto en el Océano Índico occidental
Resumen
Una inusual montaña submarina revela rocas del manto superior oceánico profundo, levantadas más de 2 kilómetros. Esta característica geológica es el resultado de la subida del manto y la actividad tectónica a lo largo de una zona de fractura.
Área de la Ciencia:
- * Geología marina geología marina.
- * Petrología * Petrología.
- * Tectónica de las tierras.
Sus antecedentes:
- * Un alto topográfico anómalo cerca de la zona de la fractura de Owen y la intersección de Mid-Indian Ridge expone rocas ultramaficas.
- * Estas rocas, incluidas las lherzolitas, harzburgitas y dunitas, carecen de texturas acumuladas.
Objetivo del estudio:
- * Investigar el origen y el mecanismo de elevación de un bloque expuesto del manto superior oceánico.
- * Analizar la petrología y la química mineral de las rocas ultramaficas desde las alturas topográficas.
Principales métodos:
- * Observaciones de campo de la altura topográfica.
- * Análisis textural de muestras de rocas ultramaficas.
- * Análisis químico mineral de los cristales de olivina, piroxeno y espinela.
Principales resultados:
- * Las rocas ultramaficas se originaron a profundidades de al menos 25 km en la litosfera oceánica.
- * Se observó evidencia de reequilibrio parcial y recristalización durante el ascenso.
- * Los datos indican un bloque elevado del manto superior, no una sección típica de la corteza oceánica.
Conclusiones:
- * Las rocas ultramaficas expuestas representan un bloque significativo del manto superior oceánico.
- * Un proceso de dos etapas que involucra el surgimiento del manto y la elevación tectónica de la zona de fractura explica el desplazamiento vertical sustancial.
- * La tasa de elevación a lo largo de la zona de fractura se estima en aproximadamente 1 milímetro por año.
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