Structural evolution and deformation control on mineralization in the Central Draâ Sfar Cu-Zn VMS deposit (Jebilet Massif, Variscan belt, Morocco)
Więcej
Ukryj
1
Managem Group, Twin Center, 20000 Casablanca, Morocco
2
2GBEI Laboratory, Polydisciplinary Faculty of Taroudant, Ibn Zohr University, Agadir,
3
Geodynamic and Geomatic Laboratory Department of Geology, Faculty of Sciences, Chouaïb Doukkali University, EGGPG, B.P. 20, 24000 El Jadida, Morocco
4
LAGAGE Laboratory, Department of Geology, Faculty of Sciences Ibn Zohr University, 80000 Agadir, Morocco
5
Applied Geology and Remote Sensing, Moulay Ismail University of Meknes, Faculty of Sciences and Techniques, BP 509, Errachidia Boutalamine, 52000, Morocco
Autor do korespondencji
Imad AFLLA
Managem Group, Twin Center, 20000 Casablanca, Morocco
SŁOWA KLUCZOWE
DZIEDZINY
STRESZCZENIE
The Draâ Sfar polymetallic deposit in the Central Jebilet (Morocco) is a Variscan volcanogenic massive sulfide (VMS) system in which orebody geometry is strongly overprinted by polyphase deformation. This study aims to determine how Variscan tectonic processes have controlled the architecture, distribution, and apparent multiplicity of sulfide lenses in the poorly documented Central Block at ~640 m depth, and to distinguish between primary depositional features and tectonically induced segmentation of mineralization. The study further seeks to evaluate the relationship between deformation, hydrothermal alteration, and metal redistribution within a structurally complex VMS environment. To achieve this, an integrated approach combining drill-core logging, structural analysis, petrography, X-ray diffraction, and whole-rock geochemistry was applied to representative sections of the Central Block. Lithological correlations and deformation fabrics were used to reconstruct orebody geometry, while geochemical indices (AI, CCPI, ISER) were employed to quantify alteration zoning and its spatial relationship to structural domains. The results show that sulfide mineralization occurs predominantly as pyrrhotite-rich lenses associated with chalcopyrite, sphalerite, and pyrite, which are systematically folded, boudinaged, and segmented by ductile shear zones and late brittle faults. The apparent multiplicity of ore lenses is demonstrated to result largely from tectonic duplication of originally continuous mineralized horizons rather than independent depositional centers. Alteration patterns display a clear structural control, with proximal chlorite–carbonate–pyrite assemblages concentrated within high-strain zones and distal sericite-rich halos developed in the surrounding wall rocks, reflecting deformation-enhanced fluid circulation. The paragenetic evolution records three main stages, from syngenetic sulfide deposition to syn-deformational remobilization and late fracture-controlled mineral precipitation. The study is limited by the discrete nature of drill-core sampling and the absence of continuous 3D geophysical constraints, which restrict full spatial reconstruction of ore continuity. Nevertheless, the results provide a robust framework for understanding structurally reworked VMS systems and improve predictability in exploration targeting. This work demonstrates that Variscan deformation is the principal control on orebody architecture in the Central Block of Draâ Sfar, offering a revised genetic model for tectonically modified VMS deposits and providing a transferable approach for interpreting similar deformed sulfide systems in orogenic belts.