formation de fer
- Domaine
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- géologie
Termes :
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Ferrugineux : Qui contient du fer ou l'un de ses composés ferreux (Fe 2+) ou ferriques (Fe 3+).
Terme associé :
- formation ferrifère n. f.
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Ferrifère : Se dit d'une roche sédimentaire contenant du fer (sel ou oxyde).
Acception plus restreinte; le fer contenu dans les formations de fer ne se présente pas seulement sous forme d'oxydes.
Traductions
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anglais
Auteur : Université Laval,Définition
A chemical sedimentary rock typically thin-bedded and/or finely laminated, containing at least 15 % iron of sedimentary origin and commonly but not necessarily containing layers of chert [...].
Note :
Iron-formations in general are subdivided [...] into four facies -sulfide, oxide, carbonate, and silicate- according to their anion content. The facies variants are gradational into one another and offer useful indicators for basin analysis studies, the shallow to deep order of facies development coinciding with oxide, carbonate, and sulfide types of iron formation [...]. [...] High Eh favored oxide facies development, whereas a strongly negative Eh favored sulfide facies iron-formation. The silicate and carbonate facies required intermediate Eh values. [...] Iron ore deposits occur in all facies types except silicate. Most of the orebodies mined around the world are in oxide facies.
Termes :
- iron-formation
- IF
- iron formation
Terme associé :
- exhalite