Morphometric analysis is a pertinent scientific approach in any hydrological analysis, and it is necessary in the progress and management of drainage basin. Identification of areas at risk of erosion, and the prioritization of 48 sub-watersheds of Inaouene basin, was done by using linear, relief and areal aspects of watershed. The research carried out the use of geographic information system spatial data. The linear aspects include stream number, stream sequence, stream length, and bifurcation ratio, mean length of stream order, stream length ratio, mean stream length ratio, and form factor. The areal aspect includes frequency of stream, drainage density, texture ratio, channel length constant, and overland flow maintenance length. Ultimately, the relief dimensions included relief proportion, relief and ruggedness number. The array of compound (Cp) values computed allow us to set the priority ranks and classify the sub-watershed into three priority ranks groups: low, moderate, and high priority. Such morphometric analyses can be used therefore as a watershed erosion status estimator to prioritize land and water conservation initiatives and natural resources management.

The study of landslides in the Inaouene watershed (northeastern Morocco) provides information on the relationships between landslides and morpho-structural analysis. Landslides affect part of the slopes and slopes of the valley. The configuration of this relationship is controlled by the combination of several predisposing factors. Two localities were studied, located in similar morpho-structural contexts, but characterized by a different lithology. The first determining factor was lithology, in particular the dominance of friable geological formations, especially marls in the locality of Chebabate and limestone soft formations in the locality of Tahla. The second factor was the tectonics, which is well individualized in the limestone of Tahla; in spite of friable lithology of the marls of Chebabate, one manages to disturb traces of the tectonics notably with the level of intercalation of the sandstone benches. Another factor that controls the dissection and the evolution of the landslides is the precipitation by the effect of abundance of the water of impregnation in the formations. The fieldwork is devoted to the measurement of the different faults encountered in the two localities to make the stereographic projection in order to elaborate canvas. The principal objective of this study is to find the relation between the evolution of the risks of erosion and landslide as well as the various factors, who control their spatiotemporal evolution. The results obtained will help managers and decision-makers in the development of watersheds in order to take the necessary steps to reduce the negative impact of this natural hazard on the environment, the population and their property.

There are many factors which affect the hydrological, geomorphologic and hydrogeological condition of the area. In order to better comprehend all processes, a Digital Elevation Model (DEM) was developed based on Geographical Information System. This latter appears as an essential tool to facilitate the decision support and can provide very important geological information. In fact, the use of the DEM is growing dramatically with the use of the GIS and the improvement of information extracted from elevation data such as mapping of floods, forest areas, erosion, and lineaments. The spatial distribution of topographic attributes can often be used as an indirect measure of the spatial variability of these processes and allows them to be mapped using relatively simple techniques. The main purpose of this study is to model the natural surface of the earth as the most accurate and the most precise. For this end we have tried in this work to develop various types of Digital Elevation Models DEM of the Foussana rift in Central Tunisia and to demonstrate the role of these models in geological, hydrogeological and hydrological study. The 3D model is also coupled in this study with piezometric and hydrochemistry study, so a new information’s plan was mapped by multiple GIS techniques like Spatial analysis and interpolation; in order 1) to comprehend the hydrodynamic of the aquifer, 2) to quantify surface and subsurface water resources and 3) to generate water management scenarios in the study area. To this end, several groundwater samples were collected and analyzed from wells and piezometers. Examining the corresponding physical and chemical parameters showed an increase in the concentrations of hydraulic conductivity in the center of the study area and it coincided with zones with high nutrient concentration. Recommendations are proposed in this zone.

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The Allochthonous Visean limestones of the Eastern part of the Moroccan central massif, occurring along the front of the Jebel Bou Khmis thrust fault, between Mrirt and Amghass, have undergone a structural and microtectonic study, aiming to study fracturing and its relationship between folding. The microtectonic studied sites were selected in different folds and in different parts of the same fold (long and short limbs and in the hinge) in order to study the relationship with fold geometry and fracturing, and to show the control of the facies and its importance in the genesis of fracture networks. The sub-vertical fractures family appear to be anterior to sub-horizontal once. They correspond to the first deformation accompanying the first shortening phases during the layer parallel shortening (LPS). The horizontal fractures were developed by accommodating of the fold when extending vertically during the amplification of the hinge. These three fracture families are syn- to post major folding phase that generated penetrative NE-SW oriented cleavage. The same results were obtained from microscopic study of thin sections, selected among oriented limestone samples, within oolites, calcite crystals and fluid inclusions.