The first Neogene deposits in the northern Middle Atlas are the Vallesian (Middle-Upper Tortonian) lacustrine and palustrine series of the Oued Zraa and Oued Mdaz basins. The first is part of the tabular Middle Atlas and consists of a terrigenous, conglomeratic, and micro-conglomeratic formation at the base, which is topped by volcanic and volcano-sedimentary layers sealed by marl-limestone alternations. The second basin belongs to the folded Middle Atlas, defined by micro-conglomeratic and silty-sandy deposits at the bottom, topped by marly layers and surmounted by white limestone formations. These deposits are affected by ductile and brittle soft-sediment deformation structures (SSDS), such as sedimentary veins, normal and sealed reverse faults, boudinages, symmetrical and asymmetrical folds, and load structures. The trigger mechanism investigated for these deformations, combined with the tectonic and microtectonic analyses carried out in the two basins, reveals that these hydroplastic deformations are seismic in origin and can then be defined as seismites. This tectonic activity correlate to the Vallesian tectonic phase in the Middle Atlas range, with WNW-ESE to NW-SE σ1 stress axis and NE-SW to NNE-SSW stress σ3 axis, with the permutation of axes σ1-σ2 and σ2-σ3. These tectonic activities induced the normal faulting of the Aït Choaib and Taghout Ouzemour faults, oriented NW–SE within the Oued Mdaz basin, as well as along similarly oriented faults in the Oued Zraa basin. These faults controlled the formation and evolution of both basins. The Vallesian tectonic phase is divided into two episodes: NE-SW extensional episode and NW-SE compressional one. This leads to the appearance of NE-SW reverse faults, symmetrical and asymmetrical syn-sedimentary folds, with axial planes striking in NE-SW direction.

The north-eastern part of the Tichoukt Ridge (folded Middle Atlas, Morocco) is a critical area for understanding the structural evolution of major faults crossing the Middle Atlas belt, their role in the structuring of Jurassic basins, and their influence on the Miocene deposits delimitation. However, this sector still lacks a detailed and updated geological map, which limits the understanding of its structural framework and lithological distribution. To address this gap, this work integrates remote sensing data from Landsat 9 OLI, ASTER and Sentinel-2 images, enhanced to high spatial resolution (5 m) by a panchromatic band from SPOT 5 HRS-2 sensor, with field investigations to produce detailed geological map at 1/50 000 scale. The use of color compositions optimized by OIF and PCA appears to have enabled the accurate discrimination and delineation of the geological formations present in the study area. Structural lineaments were manually extracted from the directionally filtered multispectral images. The structural lineaments identified have been grouped into two main systems. Faults inherited from the Paleozoic basement, responsible for the Atlas rifting, are included in the NE-SW to ENE-WSW system. The NW-SE transverse system corresponds to faults newly developed during the Jurassic (Middle Liassic). Paleostress analysis of fault-kinematic data revealed an NE–SW extensional to transtensional regime during the Bathonian, responsible for the subsidence and structural compartmentalization of the Jurassic basins through synsedimentary normal faulting. This tectonic phase was followed by NW–SE to NNW–SSE compressional-transpressional episodes, expressed by reverse and thrust faulting associated with dextral strike-slip reactivation of the major Middle Atlas fault systems during the Late Miocene–Pliocene. Furthermore, ASTER spectral band-ratio analysis identified two hydrothermal alteration anomalies, whose field validation confirmed the presence of polymetallic mineralization enriched in Pb, Cu, Mn, and Fe. The scientific and economic potential of the studied area is highlighted by these results, enhancing its relevance for geological research and mineral resource exploration.

The Aouli Pb-Zn-Cu-Ba vein-type district is part of the Upper Moulouya massif (UMM) (Eastern Meseta, Morocco). Five vein ore deposits including Aouli, Sidi Ayad, Poulet, Sidi Said and Ansegmir belong to this district. This paper aims for a precise and in-depth geometric-gitological description of the ore-bearing structures in the Aouli vein system (AVS), as well as their structural-palaeostress analysis and the tectonic-geodynamic setting of their emplacement. Geological mapping allowed identifying several fault-filling sulfide-barite veins cutting the Cambro-Ordovician metasediments and Triassic series. They extend over multi-kilometer length and are of meter to decimeter thickness. The structural analysis revealed two main directional systems for these veins: (i) NNE-SSW to NE-WS and (ii) ENE-WSW to E-W. The palaeostress fields associated with vein development and mineralisation emplacement are consistent with a pure extensive tectonic regime. The calculated palaeostress tensors indicate a NW-SE to N-S subhorizontal to horizontal sigma 3 axis and a subvertical sigma 1 axis with tectonic regime index R ' ranging from 0.27 to 0.43. The AVS is controlled by normal faults developed during extensional tectonic events resulting from the Atlasic-Central Atlantic-Tethys rifting stage during the Upper Triassic-Lower Liassic times in the north-western Gondwana margin. The trigger mechanisms for metallogenic processes are crustal thinning and the Central Atlantic Magmatic Province (CAMP) activity. At regional scale, these metallogenic events are related to the Pangea breakup, where the main process for the deposition of the major Mesozoic hydrothermal deposits was the Central Atlantic-Tethys-Caribbean rift system in North Africa and Western/Central Europe. (c) 2026 The Geologists' Association. Published by Elsevier Ltd. All rights are reserved, including those for text and data mining, AI training, and similar technologies.

Copper mineralization in the Moroccan Atlas Mountains remains insufficiently characterized, particularly within the Middle Atlas, where the metallogenic framework and structural controls are still poorly constrained. Previous research has mainly focused on the better-documented Anti-Atlas and High Atlas provinces, leaving a significant knowledge gap concerning the geological and tectonic factors governing copper deposition in this orogenic belt. To address this gap, the present study applies an integrated and reproducible methodological framework that combines remote sensing analysis, structural interpretation, and field-based geological validation to evaluate the metallogenic potential of the Middle Atlas. Principal Component Analysis (PCA) was performed on Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) data to extract major structural lineaments, while spectral band ratio techniques were employed to map hydrothermal alteration zones indicative of copper mineralization, including sericitic, argillic, propylitic, and ferruginous alterations. Through this integrated methodological framework, favorable zones for significant mineralization were accurately delineated, primarily along major tectonic structures. Field investigations confirmed the presence of copper mineralization occurring in two main morphological types: (i) vein-type mineralization hosted within fault zones and tension gashes, and (ii) stratiform mineralization within sedimentary layers interbedded with Triassic doleritic basalt flows. Structural analysis indicated that the mineralization is spatially and temporally associated with two principal tectonic phases: (i) a NW-SE to WNW-ESE extensional regime corresponding to the main mineralizing phase, and (ii) a NW-SE compressional phase responsible for the development of NNE-SSW sinistral and WNW-ESE dextral strike-slip faults, which locally remobilized earlier mineralized structures together with manganese occurrences. These tectonic activities resulted in the deformation of pre-existing mineralized structures, forming NW-SEoriented tension gashes filled with quartz and traces of malachite. Petrographic and mineralogical analyses reveal a paragenetic sequence dominated by copper sulfides (chalcopyrite, chalcocite, bornite, and covellite), followed by secondary copper carbonates (malachite, azurite) and late-stage iron oxides (hematite, limonite), indicating a complex hydrothermal-supergene evolution. These results provide concrete insights to effectively guide mineral exploration in the ug.

The Tazekka Variscan Massif, located in the northeastern part of the Middle Atlas Belt in Morocco, is a significant geological structure hosting a wide range of polymetallic vein deposits, including lead–zinc, copper, barium, iron, silver, gold, and antimony, mainly within Paleozoic rocks. These mineralizations exhibit lateral mineralogical zonation between two domains of the Tazekka Inlier and are closely associated with a complex tectonic evolution. To better understand the metallogenic and structural framework, an integrated approach was applied, combining paleostress analysis based on fault-slip data inversion with detailed field observations of slickenside-bearing faults. The results reveal four main tectono-metallogenic phases. The first phase involves a NW–SE compression characterized by the development of N30–50 fracture cleavages, N150–170 sinistral strike-slip faults, and N10–40 reverse faults with strike-slip components, mineralized with barite and iron-rich quartz. The second phase, dominated by strike-slip deformation, reflects a NE–SW compressive direction and NW–SE extension, resulting in N20–40 dextral and N60–80 sinistral strike-slip faults, as well as N150–170 reverse faults with dextral oblique slip. These structures are associated with antimony, barite, and sulfide veins within a milky quartz gangue. The third phase corresponds to a mixed compressional-extensional regime with a sub-meridional to NNW–SSE shortening direction and ENE–WSW extension. It is marked by N60–80 dextral-reverse faults, N10–30 sinistral strike-slip faults, and N130–150 dextral-normal faults, which host sulfides, barite, iron oxides, and hydroxides. The final phase reflects an extensional regime with NW-directed stretching and vertical shortening, characterized by N30–60 normal faults with a dextral component. These faults are filled with barite and are responsible for the tilting of Paleozoic rocks. This last phase is attributed to Late Triassic–Early Jurassic rifting that influenced regional basin dynamics and hydrothermal fluid circulation.

The Aderj area, part of the northern Middle Atlas of Morocco, is characterized by significant manganese oxide mining potential. These are associated with calcite components and iron oxides mainly hosted by Upper Triassic doleritic basalts, Liassic flint limestones and Vallesian (Middle-Upper Tortonian) lacustrine formations. However, the petrographic and mineralogical characteristics of this mineralization, along with its origin and emplacement mode, remain poorly defined in the study area. Addressing these gaps is essential for assessing the mining and economic potential of this region. This paper involves a meticulous field work approach, including detailed geological surveys of the different host series, as well as careful analysis of the mineralogical typology and morphology. Moreover, the petrography, mineralogy and geochemistry of these Mn(-Fe) mineralization allows to characterize the composition and geochemical features in order to propose an emplacement model of the Mn mineralization, which haves never been the subject of previous investigation. X-ray diffraction combined with light and scanning electron microscopy reveal a polyphase manganese and iron oxide sequences mainly formed from Mn2+ rich-hydrothermal fluids derived from leaching and hydrothermal alteration of ferromagnesian minerals from Upper Triassic basalt flows. This sequence is also enriched in geochemical elements such as Pb, Zn, and Ba resulting from the alteration of K-feldspar, probably derived from deep magmatic rocks. Fluids flow along the fractures and faults which affect this area, and deposited mineralization in fracture zones as veins and veinlets during their ascent and mixing with low-temperature, well-oxygenated surficial waters.

The unconfined aquifer hosted within the Lower to Middle Liassic carbonate formations of the Middle Atlas Causse (Morocco) serves as a critical water resource for both domestic and agricultural use in the El Menzel-Ribat El Kheir region in the Sefrou Province. This study investigates the structural controls on groundwater dynamics and aquifer geometry, with the aim of improving water resource management in a region increasingly affected by water scarcity. A multi-source geostructural analysis was conducted by integrating remote sensing data and field investigations. Lineament mapping was performed using the first principal component (PCA-1) of Landsat 9 imagery and hillshade models derived from ASTER-DEM. These were complemented by detailed geological fieldwork and structural measurements, including analysis of striated faults, joints, and tension cracks. The study identified both inherited and neoformed fault systems, with dominant orientations of N30 degrees to N50 degrees, N75 degrees to N105 degrees, N120 degrees to N140 degrees, and N160 degrees to N10 degrees. Rose diagram comparisons between remote sensing data and field observations confirmed a strong correlation between extracted lineaments and major fault trends. These faults, generated and reactivated through polyphased tectonic activity from the syn-to post-Upper Miocene, have played a fundamental role in shaping aquifer compartments. Overlaying piezometric data from wells and boreholes onto fracture maps revealed a southeast-to-northwest groundwater flow direction, aligned with NW-SE-trending faults and generally perpendicular to Quaternary N30 degrees faults. These structural features have contributed to the tectonic compartmentalization of the area into synthetic tilted blocks, promoting NW-directed collapse. This structural configuration facilitates the emergence of major springs, Ain Mehraz, Ain El Kebir, Ain Tazroute, and Ain Tamezoughte, along fault zones and tectonic intersections.

The Neogene period in Morocco was characterized by polyphasic tectonic activity, extending from the Late Miocene to the Quaternary. These tectonic dynamics led to the formation and structuring of recent fluvio-lacustrine basins, as well as the emplacement and remobilization of hydrothermal mineralization within the Atlas Mountains. Understanding the evolution of this tectonic system is crucial for guiding and facilitating mineral exploration in the Middle and High Atlas ranges. The northern zone of the folded Middle Atlas was selected for a tectono-structural study, accompanied by a modeling of the mineralizing system evolution during this period. This study considers the impact of different tectonic phases on the Neogene terrains fracturing and the manganese mineralization emplacement. The results reveal three distinct tectonic phases responsible for structuring the study area and for establishing a system of tension gashes and mineralized fault-veins. The first phase, attributed to the Upper Tortonian–Early Pliocene, led to the formation of Late Miocene deposits. This phase is subdivided into three episodes: two compressional episodes-oriented NW–SE, separated by an extensional episode-oriented NE-SW. The second compressional episode is characterized by manganese veins associated with dextral (WNW-ESE) and sinistral (N–S) strike-slip faults, along with tension gashes oriented N140 to N160, filled with manganese and iron oxides. This phase was followed by a NNW-SSE extensional phase in the Middle to Late Pliocene, marked by normal faults that facilitated the development of Pliocene lacustrine deposits. Finally, a third and more recent compressional phase, dating to the Quaternary, oriented NNE-SSW to N-S, manifested through NW–SE and NE-SW strike-slip faults, offsetting earlier dextral and sinistral structures. The tectonics in this region also influence the paragenesis of manganese mineralization within the tension gash systems. Structural and mineralogical analyses reveal a paragenesis beginning with the formation of two types of calcites, corresponding to the early stages of tension gash opening. These structures are subsequently filled in the center by carbonates and manganese oxides, concluding with the precipitation of iron oxides.

This paper aims to identify and map the Miocene series in the Northern Middle Atlas. This is to enhance our knowledge about its spatial-temporal variation. Field investigations mainly based on microtectonic measurements combined with structural analyses, lithostratigraphic studies and stress tensor inversion have allowed to reconstruct the genesis and geodynamic evolution of the Northern Middle Atlas Miocene basins. The lithostratigraphic analysis of the Neogene series unconformably deposed on the Jurassic formations shows a transgressive depositional evolution. Several stratigraphic levels have been identified; successively: (i) a conglomerate capped by Vallesian volcanic-sedimentary, lacustrine and palustrine continental series, (ii) Upper Tortonian sandstones, fluvio-deltaic conglomerates and sandy marls with channeled sandstone, (iii) Upper Tortonian-Messinian molasse, pink calcarenite, reef limestone, ochre sandy silt and blue marl. These formations are unconformably overlain by the Skoura puddingstones assigned to the Lower-Middle Pliocene. These deposits are synchronous with a major brittle tectonic phase divided into three episodes: (i) N120 to N140 Vallesian compression (N30 to N50 horizontal σ3 axis), (ii) Upper Tortonian – Messinian N45 extension (σ1 vertical). The history of the Middle Atlas during the Upper Miocene shows an opening megasequence which begins with continental sedimentation during the Upper Vallesian-Tortonian period evolving towards marine sedimentation associated to the NW-SE Atlantic transgression during the Upper Tortonian.

The Skoura hydrogeological basin, part of the Folded Middle Atlas Mountain range, is located 30 km NE of Boulemane city and 50 km SE of Sefrou city. It is limited to the North and North-East by the Aichoun reliefs, to the West by the North Middle Atlas Fault (NMAF) and to the South by the Tichoukt ridge. It corresponds to a collapsed area resulting from polyphase tectonics succeeding from the Upper Miocene to present day. Its location between two major structural lines favors the accumulation and runoff of all precipitated water. This work aims to identify the geological structures which guide groundwater and surface water flows. The geological mapping and the measurements of the water points capturing the water table, have allowed to reconstitute the geo-dynamic evolution of this basin on one hand, and to identify the various aquifers containing the water table on the other hand. The Skoura water table circulates within four aquifer systems represented by Liassic carbonates, Bathonian sandstones, Vallesian lacustrine limestone and the Plio-Quaternary fluvio-lacustrine deposits. The impermeable substratum of each reservoir layer is respectively represented from bottom to top by Triassic-Liassic red claystones, Bathonian versicolored marls, Vallesian lacustrine claystones and Upper Miocene marls. The superposition of the piezometric map with the fracturing map shows that the groundwater flow axis is multi-directional. Groundwater flows along faults and fracture, following two main directions converging towards the Mdaz River. A first flow from SW to NE characterizing the upstream part of the hydrogeological basin and a second flow from West to East which covers its central part. Concerning surface water flows, they are guided by the submeridian and transverse faults, as well as by the two major faults (NMAF and the Tichoukt Fault) which have played a major role in the genesis and evolution of the Oued Mdaz valley.

The Tazekka Variscan massif is formed by Meso-Cenozoic cover unconformably overlying the Paleozoic rocks recording polyphase tectonic stages contemporary with the emplacement of the magmatic system such as rhyolitic lavas and microdioritic dyke swarms attributed to the Upper Paleozoic tectonic phases and alkaline basaltic lavas attributed to Plio-Quaternary age. The mesostructural and tectonic analyses associated with paleo stress reconstruction are mainly based on the processing of tectonic measurement of slickensides fault planes with striation pitch determined by inversion of fault-slip data and allowed us to highlight the following tectono-magmatic events: (i) the Visean–Namurian phase is divided into two tectonic episodes. The first episode is characterized by NW–SE trending extension, while the second is marked by a relatively minor subhorizontal σ 1 compressive axis oriented NE–SW ( σ 1– σ 2 permutation). This latter episode controls the tectonic dislocation of Paleozoic rocks and the emplacement of a few rhyolitic lava flows along submeridian strike-slip faults; (ii) in the Stephanian–Permian age, the tectonic regime changes to a compressive stress state with a horizontal NE–SW trending σ 1 axis and a horizontal NW–SE trending σ 3 axis, which is what causes the development of NW–SE and NE–SW to ENE–WSW faults filled with microdioritic dyke swarms; (iii) the Permian–Lower-Middle Triassic period was marked by a compressive regime with a horizontal NNW–SSE to submeridian trending σ 1 axis and a horizontal ENE–WSW to subequatorial trending σ 3 axis, as well as NNE–SSW, WNW–ESE faults, and submeridian microdioritic tension gashes. The compression changes to WNW–ESE during the Vallesian or Lower Pliocene age. Early-Middle Quaternary is divided into two tectonic episodes with a σ 1– σ 2 axis permutation. Its axis changes from NNW–SSE associated with the ENE–WSW extension and is characterized by NE–SW faults affecting basaltic lavas. Subequatorial strike-slip faults, submeridian normal faults, and Late-Variscan brittle tectonic structures are mostly filled by basaltic lavas.

The Aouli inlier is part of the Upper Moulouya Massif located at the junction of the Middle Atlas and the central High Atlas, where outcrop a Paleozoic basement and an unconformably overlying Meso-Cenozoic cover. The aim of this paper is to describe the main fault and fracture systems that contributed to the structuring of the region during its tectonic evolution, as well as the reconstruction of the paleostress fields during the Late Hercynian period. This was achieved using a multidisciplinary approach with field surveys and measurements associated with stress tensor calculations. The structural analysis allowed us to distinguish the main faults affecting the Paleozoic basement and its Meso-Cenozoic cover on a multi-kilometer scale, as well as secondary faults whose influence can only be observed at the scale of a few hundred meters to a few kilometers. The spatial distribution of these faults shows the following directional systems: (i) the NNE-SSW to NE-SW system; (ii) the ENE-WSW to E-W system; (iii) the WNW-ESE to NW -SE system; and (iv) the NNW-SSE to N-S system. The reconstruction of the Late Hercynian paleostress fields allowed us to highlight a brittle deformation phase consistent with a regional strike-slip to transpressional tectonic regime. This phase is characterized by a subhorizontal to horizontal maximal & sigma;1 stress axis with a submeridian direction, and a minimal & sigma;3 axis also subhorizontal to horizontal with a subequatorial direction. This tectonic regime is responsible for NNE-SSW to NE-SW sinistral strike-slip faults, NW-SE dextral strike-slip faults, and ENE-WSW to E-W reverse faults with strike-slip component, as well as the development of submeridian tension gashes.

The Zeida Pb–Zn, Ba stratiform deposit is part of the Upper Moulouya mining district at the junction of the Middle Atlas and the Central High Atlas. This paper aims to identify the geodynamic–tectonic setting of the emplacement of this ore deposit, using a multidisciplinary approach combining field and laboratory work associated with paleostress analysis. The lithostratigraphic and gitological studies enable descriptions of Pb–Zn, Ba mineralization impregnated in the Upper Triassic arkose beds unconformably overlying the Variscan biotite-bearing granites. The mineralogical study allowed determination of a primary paragenesis mainly composed of galena + barite with lesser copper and zinc sulfides (chalcopyrite, covellite and sphalerite). The supergene paragenesis is represented by galena oxidation products associated with iron and manganese oxides. The structural analysis revealed a complex fracture network controlling ore deposition with three main directional systems: (i) NNE–SSW to NE–SW system; (ii) ENE–WSW to E–W system, and (iii) WNW–ESE system. The reconstruction of the paleostress fields synchronous with the mineralization emplacement allowed to conclude that these fractures were developed under an extensional tectonic regime linked to the Atlasic rifting, and characterized by horizontal NW–SE-trending σ 3 axis, and vertical σ 1 axis. The relative age of the emplacement of the Zeida ore deposit is assigned to the Triassic–Liassic period during a regional metallogenic event related to the opening of the Central Atlantic and the Alpine Tethys in the framework of the breakup of the Pangea supercontinent.

[fr] La boutonnière d’Aouli fait partie du massif de la Haute Moulouya situé à la jonction du Moyen Atlas et du Haut Atlas central où affleurent un socle paléozoïque et une couverture méso-cénozoïque discordante. Le but de ce papier est de décrire les principaux systèmes de failles et fractures qui ont contribué à la structuration de la région durant son évolution tectonique, ainsi que la reconstitution des paléochamps de contraintes au cours de la période tardi-hercynienne. Ceci en utilisant une approche multidisciplinaire avec des levés et mesures de terrain associés aux calculs des tenseurs de contraintes. L’analyse structurale nous a permis de distinguer des accidents principaux affectant le socle paléozoïque et sa couverture méso-cénozoïque à l’échelle plurikilométrique, ainsi que des accidents secondaires dont l’influence ne s’observe qu’à l’échelle des centaines de mètres à quelques kilomètres. La distribution spatiale de ces failles montre les systèmes de directions suivants: (i) le système NNE-SSW à NE-SW; (ii) le système ENE-WSW à E-W; (iii) le système WNW-ESE à NW-SE et (iv) le système NNW-SSE à N-S. La reconstitution des paléochamps de contraintes tardi-hercyniens nous a permis de mettre en évidence une phase de déformation cassante compatible avec un régime tectonique régional décrochant à transpressif. Cette phase est caractérisée par un axe de contrainte maximal σ1 subhorizontal à horizontal avec une direction subméridienne et un axe minimal σ3 également subhorizontal à horizontal avec une direction subéquatoriale. Ce régime tectonique est responsable du jeu décrochant senestre des failles NNE-SSW à NE-SW, dextre des failles NW-SE et décrochevauchant des failles ENE-WSW à E-W, ainsi que l’apparition de fentes de tension subméridiennes.

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 + , Ca 2+ , Mg 2+ , Cl − , HCO 3 − , SO 4 2− , NO 2 − , NO 3 − , 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.

Development and concentration of many ore deposits at the regional and district scales closely depend on structural geology, especially in polydeformed basements. The superposition of many deformation periods highlights the complexity of the structural context and expected potential location of mineralization zones. The formation and concentration of hydrothermal ore deposits is highly dependent on structural controls. On the NE flank of the Saghro massif (Eastern Anti-Atlas, Morocco), the Imiter silver mining region has been affected by multiple tectonic events since the Precambrian and throughout the Phanerozoic. In this investigation, a structural analysis of the different geological units revealed multi-stage deformation, beginning with the late Pan-African-Cadomian event, and ending with the last Cenozoic exhumation of the area. At least eight tectonic regimes have been identified. The Imiter basement, formed by the Cryogenian-early Ediacaran “flysch-like” Saghro Group, has been folded in low-grade metamorphic conditions, followed by an ENE-WSW brittle compressive event. These deformations occurred before to the early Ediacaran during the compressional and/or transpressional late Pan-African-Cadomian events (600–580 Ma). The unconformably overlaying deposition of the late Ediacaran Ouarzazate Group takes place in a WNW-ESE extensional setting and then involved in a NNW-SSE compressional event that occurred concurrently with a regional exhumation and erosion stages. A similar extensional event appears to have controlled the middle Cambrian sedimentation, the oldest Paleozoic deposits in this area. During the late Carboniferous, Variscan shortening was recorded by NW-SE transpressional deformation responsible for combined dextral strike-slip and southward thrusts. The Imiter silver mining region is part of the Moroccan Sub-Meseta Zone along with Paleozoic inliers of the Skoura and Tamlelt on the southern side of the High Atlas. The Mesozoic evolution began with the Late Triassic NNW-SSW transtensional tectonic regime with a northeast trending CAMP (Central Atlantic Magmatic Province) dyke during the Pangea breakup. Ultimately, the Imiter silver mining region experienced NNW-SSE Atlasic shortening during the uplift of the adjacent High Atlas. Over time, the direction of implemented tectonic stress and its effect on various geological units can elucidate the relationship between tectonism and hydrothermal silver mineralization in the Imiter region. In conclusion, structural analysis and investigation of paleostress development can be one of the most important factors for successful exploration plan and resource recovery in the Imiter region. An analysis of geological structures in determining feasible mineralization zones is crucial for future safe mining operation in the study area and can be extrapolated to other ore mining regions.

The High Moulouya Basin (HMB) occupies a key location between the Southern Middle Atlas and the Central High Atlas. Gravity data from the HMB show the presence of three gravity lows. Borehole data show a thin MesoCenozoic cover in the HMB that eliminates the possibility that these lows are due to sedimentary rocks. The gravity anomalies may therefore be related to hidden granitic bodies within the Paleozoic basement. In order to map these granite bodies and associated structures, gravity data sets were processed and enhanced using various mathematical techniques, transformations, and 2D gravity modeling. The following were either better defined or revealed: i) The High Moulouya Batholith is a large NE-SW trending batholith that crops out partially in the Aouli-Mibladen and Boumia Paleozoic inliers. Our study shows the continuity of this batholith with a 90 km long and 30 km wide granitic structure. ii) The Hidden Engil granite is a subcircular, relatively small granite body (20 x 18 km) located at the Middle Atlas's eastern boundary. The hidden granite of Zebzat (30 x 10 km) represents a narrow E-W trending pluton bounded by the High Atlas tectonic structures on its southern boundary. The tectonic influence of these granite bodies may explain, to some extent, the stability of the HMB throughout the development of the Atlasic subsiding basins. The two Atlas basins are separated by the High Moulouya granitecored intrabasinal high. As shown by the horizontal gradient and Euler deconvolution methods, during TriassicLiassic NW-SE extensional events, the formation of the Middle and High Atlas basins was guided by Variscan inherited faults bounding the granitic bodies of the HMB. The main factors responsible for the formation of the High Moulouya granite-cored intrabasinal high are the isostatic compensation that follows the granite emplacement during the Variscan orogeny, the distribution of strain and deformation around the granite bodies during the Triassic-Liassic extensional tectonics and their concomitant buoyancy forces.

1. Introduction The Aouli inlier, located at the Western extremity of the Eastern Moroccan Meseta is one of the most important metallogenic provinces of Morocco. It is known for the striking diversity of its geological formations and structures,as well as its numerous ore deposits, and its various industrial rocks and minerals （Emberger AN, 1965a; Margoum DA et al., 2015; Yaagoub DR et al., 2021a, with references therein）.

The Upper Moulouya massif (UMM) is located at the junction between the Middle and the High Atlas mountain ranges where outcrop a segment of the Moroccan Variscan belt and its unconformably overlying Meso-Cenozoic cover. In this paper, we propose the Cenozoic tectono-sedimentary evolution of the continental series filling the intramontane basins of the UMM using a multidisciplinary approach with multiscale geological-structural and paleostress analyses. The lithostratigraphic study shows that these series correspond to Oligo-Neogene fluvio-lacustrine sequences, alluvial fans deposits, and alluvial outwash plains, associated with volcanic rocks. Structural and paleostress analyses provide a complex tectono-sedimentary evolution marked by the superposition of four tectonic phases with changes in paleostress orientations. These tectonic phases are consistent with strike-slip tectonic regimes associated with compressional, transpressional, transtensional and extensional episodes: (i) the first tectonic phase is characterized by NW-SE trending σ1 axis, and NE-SW trending σ3 axis, with NNW-SSE to N–S sinistral strike-slip faults, ENE-WSW to E-W dextral strike-slip faults, and NE-SW reverse faults cross cutting the Mesozoic and Oligo-Miocene series; (ii) the second tectonic phase is characterized by ENE-WSW to E-W σ1 axis, and NNW-SSE to N–S σ3 axis where the subsidence of Pliocene lake basins is probably controlled by ENE-WSW to E-W extensional faults and NE-SW transtensional faults; (iii) the third phase is marked by NNE-SSW to NE-SW trending σ1 axis, and WNW-ESE to NW-SE trending σ3 axis, with submeridian dextral strike-slip faults, subequatorial sinistral strike-slip faults, NE-SW normal faults, and NW-SE reverse faults; (iv) the last tectonic phase is characterized by NNW-SSE to N–S σ1 axis, and ENE-WSW to E-W σ3 axis responsible for subequatorial reverse faults, submeridian normal faults, NE-SW sinistral strike-slip faults, and NW-SE dextral strike-slip faults.

During the Mesozoic, the basins bordering the Aouli inlier (BBAI) experienced a geodynamic evolution marked by five successive stages: (i) during the Upper Triassic-Middle Liassic (Middle Carixian?), several sedimentary basins occurred with detrital, volcanic, and carbonate filling. Sedimentation and volcanism are controlled by NE-SW to E-W normal faults developed under a NW-SE to NNW-SSE extensional tectonic regime related to the Atlas rifting stage; (ii) during the Middle Liassic (Upper Carixian?-Domerian)-Toarcian, a pure extensive tectonic regime with NE-SW trending σ3 axis is responsible for the appearance NW-SE synsedimentary normal faults. Lateral variations of facies and thicknesses of layers and basin subsidence are controlled by these faults; (iii) during the Aalenian-Bajocian, the tectonic regime is extensive with NNW-SSE σ3 axis responsible for southward deepening of the sedimentary basins bounded by ENE-WSW normal faults. Sedimentary series are represented by bioclastic limestones and a thick succession of marls; (iv) during the Infracenomanian, the tectonic regime becomes transpressive with a sub-horizontal NNW-SSE trending σ1 axis. This is responsible for the development of ENE-WSW reverse faults, NE-SW and NW-SE strike-slip faults, the folding of Jurassic series, and the deposit of ante-Cenomanian continental succession unconformably overlying the underlying series; (v) during the Cenomano-Turonian, the setting up of carbonate platform marks a marine transgression on the entire Upper Moulouya domain. This is related to an extensive tectonic regime with sub-horizontal NW-SE σ3 axis, responsible for the development of NE-SW trending normal faults that control marine transgression and the subsidence of Cretaceous basins.