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The Ouixane Fe skarn district in the northeastern Alpine Rifan belt is the highest grade iron district in Morocco with past production of 65 Mt of ore at >50 % Fe and estimated remaining reserves of 30 Mt grading 58 % Fe. Overall, the district consists of three major deposits, distributed in a 6 Â 6 km zone along the northeastern part of the Beni Bou Ifrour Massif. Mineralization occurs either within the 7.58 ± 0.03 Ma Ouixane post-collisional, hornblende-biotite quartz-diorite porphyry and related dike swarms, or more importantly at contacts of the porphyry with a *1,500-m-thick sequence of Upper Jurassic-Lower Cretaceous turbiditic and volcaniclastic sedimentary rocks. Igneous rocks have high-K, calc-alkaline to shoshonitic affinities and REE patterns that are consistent with emplacement in a typical arc setting. Concordance between the age of mineralization, which is thought to have occurred at 7.04 ± 0.47 Ma, and the 7.58 ± 0.03 Ma crystallization age of the Ouixane quartz-diorite porphyry constitutes strong evidence for a genetic relationship between Ouixane magnetite skarn mineralization and Late Neogene magmatism. Structural controls were important in focusing fluids and localizing the emplacement of late mineralizing phases. The ore zones have undergone strong post-ore displacement along steeply dipping, predominantly thrust

The Tiouit gold deposit occurs in the central part of the Precambrian Saghro inlier in the eastern Anti-Atlas orogen. It is the second-largest gold producer in Morocco with a total production of ca. 1 Mt of ore at an average grade of 7.9 g/t Au, 67 g/t Ag, and 0.45 % Cu. Host rocks consist of metamorphosed sedimentary, volcanic, and volcaniclastic rocks of the Neoproterozoic Ouarzazate Supergroup locally intruded by the synto post-tectonic, I-type, calc-alkaline Ikniwn Granodiorite and Isk-n-Alla Granite. Auriferous mineralization is restricted to the southwestern part of the hydrothermally altered 690 ± 57 Ma Tiouit granodiorite, forming discontinuous sulphide veins and disseminations that trend N-S to N10°E and dip 10°-30°E to SE. Four mineralized zones are recognized, referred to as North, Central, South, and Northeast. The veins are up to 6 m wide, averaging 1.5-2 m, and extend along strike 40-300 m. Silicified halos containing up to 2-3 % disseminated pyrite are common near the veins; the highest gold and sulphide concentrations are confined to veins that exhibit the largest pyrititic halos. Primary mineral assemblages consist of varying amounts of intergrown galena, sphalerite, chalcopyrite, pyrite, electrum, and native gold, with subordinate arsenopyrite, argentite, sulphosalts (tetrahedrite-tennantite), and iron oxides plus quartz. Native gold occurs either as: (1) inclusions disseminated in sulphide grains, typically at boundaries between pyrite-chalcopyrite and arsenopyrite-galena-sphalerite-aikinite, interpreted to constitute the first generation of gold (Au-1); (2) anhedral fillings in pyrite, where gold (Au-2) is commonly accompanied by chalcopyrite; and (3) fillings of fractures in quartz ± chlorite ± hematite ± muscovite ± K-feldspar. Owing to the absence of radiometric age constraints, the inferred age for gold mineralization is attributed to emplacement and subsequent crystallization of the Ikniwn Granite. Mineralogical, textural, and geochemical data together with fluid inclusion measurements are consistent with phase separation of an H 2 O-rich fluid containing dissolved CO 2 , which ultimately exsolved an early high-salinity aqueous fluid from the Tiouit granitic magma. This early, high-salinity and CO 2 -rich fluid progressively evolved and mixed with larger volumes of colder, oxygenated, and more acidic solutions resulting in the precipitation of the Tiouit auriferous and base-metal mineralization.

The Aouli Pb-Zn ± F ± Ba deposit in the upper Moulouya district of central Morocco consists of an array of multi-kilometer, transtensional, sub-vertical veins grouped into four main systems referred to as Aouli, Ansegmir, Sidi Said, and Sidi Ayad. Collectively, these veins produced *10 Mt of ore at a grade of 5 % Pb. Host rocks are a succession of folded and low-to medium-grade metasedimentary and minor metavolcanic rocks of Cambro-Ordovician age locally intruded by the multiphase ca. *330-319 Ma Aouli batholith. The veins occur either within the Aouli granitic intrusion (i.e., Ansgemir), Cambro-Ordovician schistose pelites (i.e., Aouli, Sidi Said), or both (i.e., Sidi Ayad). Overall, the orebodies exhibit very low Zn/Pb ratios, and contain 150-600 g/t Ag and 200-700 g/t Bi. Hydrothermal alteration is weakly to moderately developed in the vicinity and surrounding the veins, and is dominated by intense silicification coupled with minor sericitization, both types being superimposed on regional propylitic alteration. The sulphide mineralization consists principally of varying proportions of galena and sphalerite, and to a much lesser extent chalcopyrite and pyrite. Gangue minerals include multiple generations of quartz and paragenetically later fluorite and barite. Combined fluid inclusion data together with stable and radiogenic isotopic constraints indicate that the Aouli vein-type sulphide ± fluorite ± barite mineralization formed during the Permian-Jurassic contemporaneously with Pangean rifting and subsequent opening of the Tethys and Central 291Atlantic oceans. Mixing at the basement-cover interface of an ascending, deep-seated fluid that equilibrated with Hercynian crystalline basement rocks, and formation and/or meteoric water, is proposed to have triggered ore deposition.