Stratigraphic, sedimentological and magnetic study was performed on alluvial terraces, rich in archaeological tools, the region of OUM ALI, in north-eastern Algeria. The sedimentological points of view, the sediments are dominated by the sand fraction followed by the silt fraction; moderate concentrations of CaCO3 are the result of the dissolution of the surrounding limestone reliefs (Maastrichtian limestone). The morphoscopic observation of quartz grains with a dissecting microscope allows us to offer more or less significant changes, since they are often dull or sub-blunted. The results of the magnetic survey are consistent with those of the sedimentological study. The values of magnetic susceptibility are strong in the middle part of the stratigraphic section (just above the archaeological level) and decrease slightly at the top. Lower values are stored in the lower part. The dependence of frequency values of magnetic susceptibility (fd) are strong throughout the stratigraphic section and show the presence of a mixture of single-domain grain size (R), pseudo-single domain (PMD) and superparamagnetic (SP) (with a predominance of SP grains). The high concentration of SP grain size reveals the presence of significant soil formation during the implementation of the sediment

On the southwestern Tethyan Margin of Tunisia, the well-known anoxic black shale facies of the Cenomanian-Turonian transition contrasts with oxic fossiliferous carbonates, first characterized here as lateral equivalents. In terms of sequence stratigraphy, the analysis of four wisely sampled sections in Central and Southern Tunisia led to interpret these deposits as a transgressive interval (TST). This interval spans the Whiteinella archaeocretacea Zone of foraminifera and is capped with a glauconite-rich highly bioturbated maximum flooding surface (MFS). In the reference section of Oued Bahloul and the Kalaat Senan area of North-Central Tunisia, these deposits overlay a Shelf Margin Wedge made of conglomeratic and bioclastic limestones. In South-Central and Southern Tunisia, the TST is characterized by the onset of oxic facies relaying laminated carbonates with local emergence surfaces. The analysis of both oxic and anoxic facies from the Cenomanian-Turonian transition allows identifying five successive bioevent markers, known elsewhere within the Tethyan domain: the extinction of the foraminifera genus Rotalipora (or Thomasinella), the Heterohelix shift, the Whiteinella proliferation, the filament event, and the appearance of Helvetotruncana helvetica. Among these bioevents, the Heterohelix shift coincides with the transgressive surface, while the filament event announces the maximal flooding surface. These Cenomanian-Turonian transition bioevents are of a particular relevance for regional and long-distance high-resolution correlations.

The authorities of Constantine city have been working on the redevelopment and calibration of the Rhumel and Boumerzoug wadis since 2015. The latter calebrage works caused great damage to the banks, thus affecting the Quaternary geological formations in place (alluvial terraces, flood plains). A multidisciplinary research project based on a geomorphological and sedimentological approach was quickly set up to create a scientific data base before their total destruction and loss of physical traces all along the wadis. The present study focuses on the sedimentological and geochemical analysis of the alluvial deposits of Boumerzoug wadi in order to describe the sediments, to reconstitute their nature, and to interpret both the climatic evolution and the paleo-environments of the region. Sedimentological and geochemical results confirm the succession of deposition cycles linked to progressive climate change.

Le bassin d'Ain Djasser fait partie de l'ensemble Sud-Sétifien. Ce dernier est représenté par une plaine inter-montagneuse appartenant au bassin des hauts plateaux constantinois. Il est caractérisé par un climat de type méditerranéen. L'hydrologie tributaire du relief est la conséquence directe des eaux de surface et de la fonte des neiges. La synthèse géologique montre un domaine allochtone résultant d'une histoire polyphasée associant les tectoniques atlasique et alpine. Ce dernier est caractérisé par des séries sédimentaires carbonatées colmaté par d'abondantes formations terrigènes. L'alimentation de l'eau souterraine des différentes nappes profondes à semi-profondes provient essentiellement de l'infiltration des eaux de pluies. Ce cortège de roche forme une nappe libre et captive, par endroit recoupée par des forages à des profondeurs de 178 à 330 m, fournissant un débit moyen de 15 l/s. L'interprétation des coupes géoélectriques du bassin montrent, (i) des formations alluvionnaires du mio-plio-quaternaire de quelques dizaines de mètres qui forment un bon aquifère superficiel, (ii) des calcaires fissurés du jurassico-crétacé dont le toit est atteint à des profondeurs variables est un aquifère captif. L'influence d'accidents entre les différents blocs rend possible une éventuelle alimentation des aquifères entres eux. L'analyse litho-stratigraphique montre que le substratum et la couverture sédimentaire ne présentent pas de grandes variations latérales. Par contre, nous observons au niveau des sondages une variation dans l'épaisseur et la lithologie des couches, essentiellement au niveau de la formation du remplissage mio-plio-quaternaire. L'objectif de cette étude réside pour l'essentiel, dans la mobilisation des ressources en eaux superficielles et souterraine pour leurs exploitations dans les domaines agricoles et l'élevage, en vue d'une utilisation rationnelle et planifiée de cet élément vital qu'est l'eau

A hill reservoir research project aims, among other perspectives, to improve the regional agriculture potential through irrigation of small areas. For such a project, the feasibility study for a given area is fundamental before the establishment of any related applied research works. This paper is of a socio-economic relevance for the Timgad region (NE Algeria) as the presented results consist of a contribution of both socio-economic operators and policy makers. In the study area, water resources are closely related to the regional geology and the main objectives of the establishment of the Foum-Toub hill reservoir is to promote the irrigation of its plain, regulate the flow of the Foum-Toub creek and minimize the silting of the Koudiet Lemdaour dam. The selected sites for the construction of this work are characterized by an impermeable bedrock. Loose material, favorable to serve as borrow areas, can be supplied from the surrounding depressions where sandstone can also be used for the dike construction.

Field observations and sedimentological analyses of alluvial terraces of the O. Gourzi (Batna, NE Algeria) lead us to consider sediments as dominated by clayey and silty-sandy fractions overlain by gravel and calcareous coarser fractions. Moderate CaO₃ contents would have resulted from the dissolution of the nearby carbonate relieves. They are mainly composed of Maastrichtian limestones. The distribution of the mineral fraction led us to identify 07 levels including horizons of coarse fractions alternating with layers rich in sand and silt with a roughly constant clay fraction through the stratigraphic column. Kurtosis values, frequency histograms of a prokurtic type, rarily mesokurtic, mark a constant power mode for the transport agent. Classification indices indicate poorly- to moderately sorted material, indicating a turbiditic depositional environment. Quartz grain nature and morphoscopy refer to Miocene sandstones as a potential origin. The ferruginous coating is due to the initiating pedogenesis.