Recharge characterization by geoelectrical imaging and the GIS of the Plio-Quaternary aquifer (a case study of Central Haouz- Marrakesh)

Groundwater resources in Morocco are increasingly scarce. The study area which is Central Haouz belonging to the Marrakech plain is not immune to this phenomenon. This is due to the semi-arid climate on the one hand, and on the other hand, due to accelerated population growth and the economic development implications. The Plio-Quaternary aquifer of the Central Haouz has been the subject of several studies, but its Hydrogeological characterization has been classically carried out using geological and pumping test studies. Our study is in this sense to show the importance of the contribution of GIS and Electrical Resistivity Tomography (ERT). The first GIS approach determined the Runoff coefficient, which helps to locate low runoff areas corresponding to recharge zones of the water table. These areas are chosen as the site for geophysical surveys. The second method consists to detect the effect of the recharge to increase the water table in the study area and the characterization of the aquifer. Four ERT surveys were performed showed on the aquifer the positive effect of the recharge dike recently built at the Wadi and dismantle the reliability of the GIS results concerning the infiltration zones founded

Géométrie de l'aquifère du Haouz oriental et Tassaout amont, Maroc occidental: approche géophysique et hydrogéologique

The aim of the present study is to improve the knowledge of the geometry and hydrogeology of the eastern Haouz aquifer and part of the Upper Tassaout aquifer, using the analysis and interpretation of boreholes, gravimetric analysis, seismic reflection and piezometric data. The examination of the gravity data shows that the Bouguer anomaly map is affected by a regional gradient increasing from the southeast to northwest. This gradient was determined and subtracted from the original data, to provide a residual gravity map which shows clearly highlighted anomalies. These anomalies generally reflect outcrop areas of the basement and the variation in thickness of the sedimentary cover across the study area. The seismic reflection profile confirms the gravity results, and shows that the region is formed by a horst which corresponds to the exposed bedrock of Jebilets in the north of Haouz basin, and a subsidence area where coverage is widespread in the south of the plain of Haouz. In this area, the large thickness of the cover allows the accumulation of water and provides the recharge of the groundwater reservoir. The rise of the basement in the north of the Haouz basin imposes a dividing line of two groundwater flow direction

Assessment of Soil Quality for a Semi-Arid Irrigated Under Citrus Orchard : Case of the Haouz Plain, Morocco

The irrigated perimeter of the Haouz plain is one of the largest in Morocco with 310.000 Ha with intense agricultural practices based on irrigation. Besides, recent studies have shown that the aquifer is characterized by an overall average to low sensitivity and vulnerability. The objective of this study is to provide an in depth diagnosis of the current situation regarding soil quality for a drip irrigation area: a citrus orchard, in a farm named Agafay, is located in the western part of Haouz, at 35 km SW of Marrakesh. To this objective, an intensive in situ campaign has been carried out focused on the measurements of the physico-chemical parameters of soil, at nine plots. The variation of these parameters, their impact on the type of rootstock and the variation of pollutants through the five soil horizons are analyzed. The results revealed that the condition in the soil quality is not very alarming. As most of the soils are light-textured, with poor organic matter content and basic to very basic pH. The reduction of organic matter, salinity, orthophosphates and nitrates with depth is attributed to the localized mode of irrigation adopted at the site which minimizes the loss of nutrients and, in fine, pollution of the aquifer. Multivariate analysis shows that the total and lime correlate well with the pH, which in turn correlate negatively with nitrate content and soil electrical conductivity. This work has strong implications for the quality assessment of soil for all irrigated perimeters by the drip in semi-arid areas, order to ensure the conservation and sustainability of the production system

3D geological model of the Eastern Haouz region (Morocco): hydrogeological implications.

The Eastern Haouz in Morroco is an agricultural region in fulldemographic, economic, and touristic expansion. To meet the increasinglygrowing demand of water, this paper focuses on the geological modelling ofthe basin geometry and on understanding the groundwater circulation. Thiswork presents a geological model of the study area by integrating geologicaland hydrogeological aspects. It aims to describe a natural complex object bysimplifying it to a conceptual and a numerical model. This is aimed atproviding a better understanding of the geometry and the characteristics of thereservoir. The cross-sections and the treatment of deep boreholes dataconfirmed the results of geological modeling. It, however, shows that theregion is synclinal and surrounded by two outcrops: the Jebilet and the HighAtlas mountains. At the South of the plain, the large thickness of the covergives a good accumulation of water and ensures the reservoir supply. The rise of the basement in the north of the plain imposes a dividing line with twogroundwater flow directions

Experimental study on a scaled test model of soil reinforced by stone columns

International audienceThis paper presents results of experimental tests on soil specimens reinforced by stone columns. The experimental investigations have been conducted by the setup of a laboratory scale model. Main objective is to evaluate the effects of various reinforcing materials and stone columns configurations on the axial deformation during a vertical loading test of cylindrical samples of unreinforced and reinforced soil. The findings have been compared to existing experimental results proposed in the literature. The specimens of soil have consisted of an analogic material of glass beads poly-dispersed grain size smaller than 50 μm. Two reinforcing materials have been considered as ballasts: crushed sand and coarser granularity glass beads (0.7 – 1.0 mm). The results show that the material type and spacing between columns in a triangular or square configuration can greatly affect the reinforcement efficiency

3D Geological Model of the Eastern Haouz Region (Morocco): Hydrogeological Implications

International audienceThe Eastern Haouz in Morroco is an agricultural region in full demographic, economic, and touristic expansion. To meet the increasingly growing demand of water, this paper focuses on the geological modelling of the basin geometry and on understanding the groundwater circulation. This work presents a geological model of the study area by integrating geological and hydrogeological aspects. It aims to describe a natural complex object by simplifying it to a conceptual and a numerical model. This is aimed at providing a better understanding of the geometry and the characteristics of the reservoir. The cross-sections and the treatment of deep boreholes data confirmed the results of geological modeling. It, however, shows that the region is synclinal and surrounded by two outcrops: the Jebilet and the High Atlas mountains. At the South of the plain, the large thickness of the cover gives a good accumulation of water and ensures the reservoir supply. The rise European Scientific Journal August 2018 edition Vol.14, No.24 ISSN: 1857 – 7881 (Print) e - ISSN 1857- 7431 54 of the basement in the north of the plain imposes a dividing line with two groundwater flow directions

Géométrie de l'aquifère du Haouz oriental et Tassaout amont, Maroc occidental: approche géophysique et hydrogéologique

The aim of the present study is to improve the knowledge of the geometry and hydrogeology of the eastern Haouz aquifer and part of the Upper Tassaout aquifer, using the analysis and interpretation of boreholes, gravimetric analysis, seismic reflection and piezometric data. The examination of the gravity data shows that the Bouguer anomaly map is affected by a regional gradient increasing from the southeast to northwest. This gradient was determined and subtracted from the original data, to provide a residual gravity map which shows clearly highlighted anomalies. These anomalies generally reflect outcrop areas of the basement and the variation in thickness of the sedimentary cover across the study area. The seismic reflection profile confirms the gravity results, and shows that the region is formed by a horst which corresponds to the exposed bedrock of Jebilets in the north of Haouz basin, and a subsidence area where coverage is widespread in the south of the plain of Haouz. In this area, the large thickness of the cover allows the accumulation of water and provides the recharge of the groundwater reservoir. The rise of the basement in the north of the Haouz basin imposes a dividing line of two groundwater flow direction