Komatiites
- Komatiites
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Komatiite
Échantillon de komatiite.
La komatiite est une roche volcanique ultramafique. Elle tient son nom de la rivière Komati, en Afrique du Sud, où elle est particulièrement visible.
Les komatiites sont très rares et essentiellement limités aux roches d'âge archéen. La plupart sont veilles de plus de deux milliards d'années et on ne connaît en raison de leur âge que des komatiites métamorphisées (en toute rigueur des métakomatiites).
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Catégories : Roche volcanique | Roche métamorphique
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