Géologie, géochimie et géochronologie du gisement aurifère de Tamlalt-Menhouhou (Haut-Atlas oriental)

Abstract : The Tamlalt-Menhouhou gold deposit is located on the southern edge of the Neoprotérozoic-Palaeozoic Tamlalt inlier (Eastern High-Atlas), just north of the limit between the High-Atlas belt and the Anti-Atlas belt. Mineralizations are enclosed in Ediacaran volcano-sedimentary formations (U/Pb age: 569 + - 8 Ma). Two different gold mineralizations were identified : (i) a primary gold mineralization of the type Iron Oxide Copper Gold deposit (IOCG) characterized by a strong sodic (+ - calcic) alteration and (ii) a secondary gold mineralization corresponding to a Shear zone related gold deposit and related to a strong argillic and phyllic alteration localized along the shear faults. A detailed ion microprobe study of hydrothermal zircons genetically associated with albitization provide a Late Ordovician age (449 + - 8 Ma) for primary gold mineralization. This age is confirmed by 40Ar/39Ar dating of two muscovite mono-grains, and underscores the potential of zircons to record hydrothermal events, and the interest of these phases for metallogeny. A Late Variscan age (293 + - 7 Ma) is defined by 40Ar/39Ar analysis of phengites from the phyllic alteration synchronous with auriferous quartz vein development, and which is assumed to represent the age of gold mineralization. This age demonstrates the consequences of the Variscan orogeny for the re-mobilization of metalliferous pre-concentrations.
Document type :
Theses
Complete list of metadatas

Cited literature [199 references]  Display  Hide  Download

https://hal.univ-lorraine.fr/tel-01752841
Contributor : Thèses Ul <>
Submitted on : Thursday, March 29, 2018 - 1:59:46 PM
Last modification on : Wednesday, July 25, 2018 - 9:59:33 AM

File

2007_PELLETER_E.pdf
Files produced by the author(s)

Identifiers

  • HAL Id : tel-01752841, version 1

Citation

Ewan Pelleter. Géologie, géochimie et géochronologie du gisement aurifère de Tamlalt-Menhouhou (Haut-Atlas oriental). Sciences de la Terre. Institut National Polytechnique de Lorraine, 2007. Français. ⟨NNT : 2007INPL026N⟩. ⟨tel-01752841⟩

Share

Metrics

Record views

53

Files downloads

172