A detailed biostratigraphic study of four sections (El Kantara, Menaa, Tighanimine and El Gaâga) in the Campanian–Maastrichtian of the Aures Basin in Algeria allows the identification of 109 ostracod species belonging to 50 genera. From a biochronostratigraphic point of view, none of the identified ostracod assemblages are typically restricted to the Campanian or to the Maastrichtian, but rather characterize a range covering the Campanian–Maastrichtian. As regards the paleobiogeography, the presence of species in common between Algeria and other countries or regions enables us to compile four maps showing the distribution of two provinces that developed during the Santonian-Paleocene, i) the South-West and South Tethyan Margins Province, including North Africa, the Middle East and Arabian Peninsula, and ii) the East Atlantic Margin Province, bordering West and Central-West Africa. We can also recognize relationships between the different regions making up these provinces, which remained under more or less arid, subtropical to tropical climates, with ostracods migrating according to the directions of ocean currents during the Late Cretaceous. The dispersal of the ostracods reflects marine communication between these provinces and India, the southern USA and Jamaica, Brazil and Europe.

Investigation on oil reservoirs is up to several approaches under different aspects. oilreservoir is dependent on several approaches in different aspects. Distinct settings may be considered for the qualitative and quantitative reservoir evaluation. Control on potential reservoir accumulation is related to permeability and poroslty, in addition to diagenetic and petrographic effects. ln the case study, the considered reservoir is dealing with Cretaceous Carbonate series of ConiacianSantonian age located in the South East of Constantine area (Sud-Est Constontinois). From exploration and evaluation point of view, the oil potential, in the cited area levels, remains almost unexplored. Based on logging and drilling collected data indicates that the approached level of Coniancian -Santonian age can be a tight type. Evidences is from the permeability which is ranging from 0.1 md to 50 md and porosity stretching from lYo up to 16%o. Thus, contribution of tectonic effect is minimized. In the same harmony is the diagenetic and petrographic attitude which is responsible for the compaction and lesser dissolution with occlusion mostly of the intergranular.

Prediction of soil swelling characteristics and accurate quality estimation can be of a great consideration and contribution regarding the site stability. Any concerned investigation is correspondingly an advanced priority for the project realization. Related inquiries allow potential reduction concerning financial and technical charges damage prior to any urban development. The determination of soil characteristics lead for a better recognition, and allow to make the best choice of foundation type adopted for each site. Thus, in any urban case study, much gain can be made by team work recording and surveying the related data. In the considered city of El Kouif, located in Tebessa (Algeria), several buildings have been mainly built on expansive soils. Observations indicate different severe damages which were caused mostly in the nearby structures. These damages are characterized by deflection and failure of walls. Lateral and vertical displacements evidences support the presence of shear movements and subsidence. The scale up of these movements occurrence can reach millimetric shifting dimension. Ground and subsurface risk activity affecting El Kouif city site are also related to the presence of destructive chemical components such as sulfates. The sulfate occurrence is illustrated through generally gypsum minerals concentration present in the concerned soil. During building projects, these soils, in meeting concrete and in presence of water, are source of new mineral generation such as ettringite. It consists on the assemblage of water and sulfate in addition to calcium. Source for these chemical products expansion might be associated to historical event: the city of El Kouif was the field of phosphates mining area in addition to established phosphate extraction plant. Thus, determination of soil characteristics and involvement of chemical components turn out to be the main objectives in this investigation.