The Ouarmdaz region: A new copper-silver potential of the Igherm inlier (Western Anti-Atlas, Morocco).
- 1Faculty of Sciences Ben M'sik, Hassan II University of Casablanca, Department of Geology, Geosciences and Applications Laboratory (GA). B.P. 7955, Sidi Othmane, Casablanca, Morocco. (ayoub.abouttarouk-etu@etu.univh2c.ma)
- 2Managem group, Twin Center, Tower A, Angle Boulevards Zerktouni and Al Massira Al Khadra BP 5199, Casablanca, Morocco. (M.ennabir@managemgroup.com)
The Western Anti-Atlas belt is globally renowned for hosting metallic ore deposits, including large copper-silver deposits. The Ouarmdaz-Chikh Imi Nrfi area is located southwest of the Precambrian Ighrem inlier, approximately 168 km east of the city of Agadir. This area is known for its stratiform copper-silver mineralization along the contact between the Precambrian basement and the infracambrian cover. This level is of particular interest on a regional scale because of its spatial extension.
The Igherm inlier comprises Precambrian basement formations, including polygenic conglomerates, red sandstones, and andesitic lava. The cover consists of a siltstone-sandstone series capped by Tamjout dolomites and lower limestones. These terrains are cross-cut by the Ighrem doleritic dyke and are affected by extremely discrete brittle deformation and very pronounced ductile deformation, indicating highly mineralized zones.
This area is characterized by polymetallic mineralization with copper, silver, lead sulfides, and iron oxides. These mineralizations are hosted in the infracambrian cover. Paragenesis is stratiform, vein-type, or in geodic cavities. The mineralized structures are mainly oriented NE–SW, with a dip of 30° to 50° toward the southwest.
The paragenetic study of mineralization has enabled us to identify the different metallic phases and propose a paragenetic succession. The primary paragenesis comprises pyrite, chalcopyrite, bornite, and galena. The primary mineral phases underwent metasomatism, giving rise to secondary parageneses represented by chalcocite, covellite, malachite, azurite, and iron oxides, including hematite and goethite. This mineralization features complex textures (myrmekitic, collomorphic, carrie, and continent).
The analytical data by (ICP) indicated relatively high levels of copper and copper oxide (<25.4%). Silver with concentrations ranging from 7 to 176 g/t, demonstrates a positive correlation with copper.
Scanning electron microscopy (SEM) analysis revealed that the highest copper concentrations were recorded in the malachite-rich zones. Iron and copper oxides of the delafossite type have also been identified in association with dolomite.
Keywords: Western Anti-Atlas, Ighrem, Ouarmdaz-Chikh Imi Nrfi, Mineralization, stratiform, Copper-silver deposits, ICP, SEM.
How to cite: Ayoub, A., Saida, A., Yousra, M., Mohamed, E., Mohamed, A., Lhoussayn, O., Rachid, T., Youssef, Z., Mohamed, S., and Zouhir, B.: The Ouarmdaz region: A new copper-silver potential of the Igherm inlier (Western Anti-Atlas, Morocco)., EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-5713, https://doi.org/10.5194/egusphere-egu24-5713, 2024.
