Résumé
In the Moroccan High Atlas, two sulfide deposits hosted by Jurassic dolostones underwent significant weathering. In the Cu deposit of Jbel Klakh, several stages of supergene mineralization are distinguished: (1) the replacement of hypogene sulfides in the protolith (chalcopyrite) by secondary sulfides in the cementation zone (bornite, digenite, chalcocite, covellite), (2) the formation of oxidized minerals in the saprolite (malachite, azurite, brochantite) where the environment becomes more oxidizing and neutral, and (3) the precipitation of late carbonates (calcite) and iron (hydr-)oxides in the laterite. The precipitation of carbonates is related to the dissolution of dolomitic host rocks, which buffers the fluid acidity due to the oxidation of sulfides. In the Jbel Haouanit Pb–Zn deposit, the mineral assemblage is dominated by typical calamine minerals, Cu minerals (chalcocite, covellite, malachite), and a Cu–Pb–Zn vanadate (mottramite). Galena is successively weathered in anglesite and cerussite. Sphalerite is weathered in smithsonite, which is rapidly replaced by hydrozincite. Late iron (hydr-)oxides are mainly found at the top of both deposits (laterite). Both deposits are thus characterized by specific mineral zoning, from laterite to protolith, related to variations in the mineralogy and ore grades and probably caused by varying Eh-pH conditions.
langue originale | Anglais |
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Pages (de - à) | 1049-1068 |
Nombre de pages | 20 |
journal | Mineralium Deposita |
Volume | 52 |
Numéro de publication | 7 |
Les DOIs | |
Etat de la publication | Publié - 26 juil. 2017 |
Empreinte digitale
Examiner les sujets de recherche de « Mineralogical and geochemical characterization of supergene Cu–Pb–Zn–V ores in the Oriental High Atlas, Morocco ». Ensemble, ils forment une empreinte digitale unique.Thèses de l'étudiant
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Characterization and (U-Th-Sm)/He dating of Moroccan supergene ore deposits : New insights to unravel the periods and potential causes of weathering processes.
Verhaert, M. (Auteur), YANS, J. (Promoteur), Bernard, A. (Copromoteur), Gautheron, C. (Copromoteur), HALLET, V. (Président), Barbarand, J. (Jury), Pirard, E. (Jury), Debaille, V. (Jury) & Maacha, L. (Jury), 9 sept. 2020Student thesis: Doc types › Docteur en Sciences
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