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The groundwater in the Timahdite–Almis Guigou area flows through fluvio-lacustrine and volcanic formations of Plio-Quaternary age and Liassic limestone. The groundwater resources in this area are used for drinking water and irrigation of agricultural plots. 18 groundwater samples were collected for this study. The physico-chemical and bacteriological parameters analysed, such as temperature, electrical conductivity, pH, dissolved oxygen, Na+, K+, Ca2+, Mg2+, Cl−, HCO3−, SO42−, NO2−, NO3−, faecal Coliforms, total Coliforms and faecal Streptococci, are used to characterise the quality of the groundwater and its suitability for drinking and for irrigation. The Piper and Gibbs diagrams and the saturation index were used to study the hydrogeochemical characteristics of groundwater. The quality of these was assessed on the basis of bacteriological quantification and water quality index (WQI) for drinking, and calculation of sodium percentage (Na%), sodium adsorption ratio (SAR) and permeability index (PI) for irrigation. The mineral saturation index in groundwater indicates that only carbonate minerals tend to precipitate, especially in the form of dolomite. On the other hand, the evaporative minerals are still undersaturated. The bacteriological quality and the water quality index (WQI) of this area are considered to be generally good to poor quality, with the exception of a few points, near the public dump of Almis Guigou, plateau of Lamrijate (Timahdite), Aït Hamza and Aït Ghanem, that show significant bacterial contamination and high concentrations of sodium, chlorides and nitrates. According to the calculation of the (Na%), the (SAR) and (PI), the groundwater samples are suitable for irrigation.

The MVT-type Pb-Ba mineralizations of the Mibladen ore deposit are hosted by Jurassic carbonates as well as Infracenomanian conglomerates and sandstones. The mineral paragenesis is mainly composed of galena and barite with lesser chalcopyrite and pyrite, accompanied by supergene oxidation minerals. This ore deposit is the result of a major epigenetic mineral stage with economic orebodies occuring as replacement of pre-existent carbonate rocks, fillings of karst cavities, interstratal joints, collapse-breccias, fractures and faults. Structural and microtectonic analyses we carried out in this ore deposit, allowed us to highlight two main fracture networks controlling ore deposition within karst cavities and interstratal joints: i) NNW-SSE to NNE-SSW trending tension gashes and normal faults; ii) ENE-WSW to E-W trending reverse faults with strike-slip components and transtensive relay zones. All of these structures are developed under a regional compressional tectonic regime divided into extensional and transtensional episodes (σ1-σ2 and σ2-σ3 permutations) with sub-meridian σ1 axis and sub-equatorial σ3 axis. This compressive tectonic event caused the uplift of Mibladen area and favored the circulation of mineralizing fluids along the NW-SE and ENE-WSW major faults such as Amourou and Aouli Faults, during the Infracenomanian period (Upper Jurassic-Early Cretaceous).

Au cours de la période néogène et quaternaire, le Moyen Atlas a connu une activité volcanique en relation avec des phénomènes magmatiques et tectoniques complexes. Plusieurs dizaines d'édifices volcaniques appartiennent aux types stromboliens et maars. Ce volcanisme a commencé au Miocène par des coulées, des sills, des dykes et des culots de nature alcaline. Les produits pyroclastiques émis correspondent à des basaltes alcalins, à des basanites et à des néphélinites. En raison des relations morphologiques entre le réseau hydrographique actuel, les dernières laves volcaniques et les grabens subméridiens; les basaltes du Moyen Atlas ont été attribués, sans argument structural, à la dernière phase tectonique du Quaternaire. Le but de cette note est d'exposer les résultats de l'étude de la répartition des volcans suivant les alignements tectoniques en relation avec les phases de déformation. Les édifices volcaniques sont alignés selon les directions N130, N70, N40 et N170, avec une prédominance de la direction N130. Un exemple de ce dernier alignement est la zone volcanique Timahdite-Azrou que nous interprétons comme un graben orienté NW-SE, à remplissage fluvio-lacustre au Miocène supérieur. Un autre exemple d'activité volcanique est celle liée à des ouvertures en transtension dans les zones de jonction entre des failles antithétiques (noeuds tectoniques); comme les volcans de Zelghi, d'Aguelmam Sidi Ali, de Oum Larays et de Tafraoute-Aït Bouziane. Les volcans les plus