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Troctolita cordierita-espinel, una nueva litología rica en magnesio de las tierras altas lunares
Science (New York, N.Y.)
|February 17, 1989
Resumen
Una nueva roca lunar rica en magnesio, troctolita de espinel con cordierita, fue encontrada en las muestras del Apolo 15. Este descubrimiento sugiere que los acumulados de espinela son comunes en la corteza lunar y requieren grandes impactos para la excavación.
Área de la Ciencia:
- * Geología y petrología lunares.
- * Mineralogía y geoquímica de materiales extraterrestres.
Sus antecedentes:
- * Apollo 15 regolith breccia 15295 contiene diversas litologías.
- * La comprensión de la composición de la corteza lunar requiere el análisis de muestras brecciadas.
Objetivo del estudio:
- * Identificar y caracterizar una nueva litología rica en magnesio en muestras lunares.
- * Determinar las condiciones de formación y las implicaciones de la troctolita espinosa con cordierita.
Principales métodos:
- * Análisis petrográfico de un clasto dentro de la breccia 15295.5.
- * Identificación mineralógica de la cordierita, la anortita, el olivino forsterítico y el espinel pleonaste.
Principales resultados:
- * Identificación de la troctolita de espinela con el 8% de cordierita (Mg(2)Al(4)Si(5)O(18)).
- * Este conjunto representa una nueva litología de las tierras altas lunares rica en Mg.
- * El par cordierita-forsterita indica una estabilidad de hasta 2,5 kilobares (aprox. 50 km de profundidad).
Conclusiones:
- * Las acumulaciones de espinela son un componente significativo y previamente subestimado de la corteza lunar inferior.
- * La rareza de esta litología sugiere la excavación por grandes eventos de impacto como la Cuenca Imbrium.
- * Este hallazgo amplía nuestra comprensión de la evolución y composición de la corteza lunar.
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