Mohamed Hibti - Academia.edu (original) (raw)

Papers by Mohamed Hibti

Research paper thumbnail of Hydrogeochemical and Isotopic Studies of the Kettara Mine Watershed, Morocco

Mine Water and the Environment, 2015

ABSTRACT Abstract Hydrogeological and geochemical studies of the Ketarra abandoned mine watershed... more ABSTRACT Abstract Hydrogeological and geochemical studies of the Ketarra abandoned mine watershed showed that the groundwater chemical facies is linked to the drained schist. d2H and d18O isotope analysis revealed the influence of evaporation. High levels of dissolved ions, including sulphate, in groundwater collected down-gradient of pyrrhotite tailings are evidence of acid mine drainage. However, the groundwater is low in metals and generally complies with Morocco’s drinking water standards; only wells down-gradient of the mine waste is not of good quality. Most of the groundwater is acceptable for irrigation and all of it can be used for livestock. Keywords: Groundwater _ Acid mine drainage _ Sulphide tailings _ Lithology

Research paper thumbnail of Rhizosphere bacterial populations of metallophyte plants in heavy metal-contaminated soils from mining areas in semiarid climate

World Journal of Microbiology & Biotechnology, 2004

Rhizosphere bacterial populations associated with four metallophyte plants in one of major polyme... more Rhizosphere bacterial populations associated with four metallophyte plants in one of major polymetallic (Pb-Zn-Cu) semiarid Moroccan Hercynian province (DraaˆSfar, Marrakech, Morocco) presenting long-term contamination mainly with Zn and Pb were analysed and compared to selected control soils. In the highly Zn-, Cu-, Pb-and Cdcontaminated soils, the total number of culturable heterotrophic bacteria were found in low proportions (<2.6 · 10 2 -1.6 · 10 4 g )1 soil). This bacterial content was slightly similar to that found in moderately polluted and controls soils (6.7 · 10 4 -5.8 · 10 6 ). However, the bacterial diversity and the rhizosphere/soil ratio, which compares the bacterial content (or bacterial charge) around the metallophyte plants with that in non-rhizosphere soil, were the bacteriological parameters mostly affected by heavy metal contamination. The chronic Zinc-stress results in an increase of tolerance to this metal of both the rhizosphere and non-rhizosphere bacterial communities. However, in general, the rhizosphere bacterial populations exhibited less tolerance to Zn toxicity than the bacterial population of non-rhizosphere soils. This result suggests that toxic effects of Zn decrease in the rhizosphere soils of the metallophyte plants.

Research paper thumbnail of The hydrothermal system of Central Jebilet (Variscan Belt, Morocco): A genetic association between bimodal plutonism and massive sulphide deposits?

Journal of African Earth Sciences, 2008

Central Jebilet (Moroccan Variscan Belt) hosts several Cu and Pb-Zn massive sulphide deposits tha... more Central Jebilet (Moroccan Variscan Belt) hosts several Cu and Pb-Zn massive sulphide deposits that are associated with a suite of gabbroic and microgranitic, tholeiitic to alkaline, intrusions emplaced 330 Ma ago. The intrusions and ore bodies form structural lineaments within marine Visean shales that are affected by very low to low-grade post-Visean metamorphism and contemporaneous shortening accompanied by the development of conjugate ductile to brittle shear zones. The ductile shear zones are localised in thermally softened aureoles around magmatic intrusions, while brittle deformation is common far from the intrusions. The intrusions have induced a contact metamorphism that reaches the hornblende hornfels facies, and their emplacement was accompanied by hydrothermal activity that leached base metals from the felsic intrusions.

Research paper thumbnail of Interpretation of magnetic data of the Laachach gossan (central Jebilets, Morocco): mining implications

In the hercynian massif of Central Jebilets (Morocco), outcrop a large number of gossans which so... more In the hercynian massif of Central Jebilets (Morocco), outcrop a large number of gossans which sometimes top economical orebodies (Kettara, Draa Sfar, etc.). The present study is devoted to the interpretation of magnetic data covering one of these iron hats, located near of the Laachach village, at about thirty kilometres north-westward of Marrakech. The magnetic map of Laachach highlights several anomalies which coincide with the outcrop of the gossan. Detailed analysis of reduced to the pole data allows us to conclude that these anomalies may be due to submeridian magnetic structures cut by a set of dextral transverse faults. These structures are generally dipping westward but they can be locally sub vertical. The Euler deconvolution of the magnetic data gives moderately deeping solutions (22 to 254 m). The quantitative interpretation of the two principal magnetic anomalies highlighted in the study area lead to better characterising of the deep structure of the Laachach magnetic b...

Research paper thumbnail of Hydrogeochemical and Isotopic Studies of the Kettara Mine Watershed, Morocco

Mine Water and the Environment, 2015

ABSTRACT Abstract Hydrogeological and geochemical studies of the Ketarra abandoned mine watershed... more ABSTRACT Abstract Hydrogeological and geochemical studies of the Ketarra abandoned mine watershed showed that the groundwater chemical facies is linked to the drained schist. d2H and d18O isotope analysis revealed the influence of evaporation. High levels of dissolved ions, including sulphate, in groundwater collected down-gradient of pyrrhotite tailings are evidence of acid mine drainage. However, the groundwater is low in metals and generally complies with Morocco’s drinking water standards; only wells down-gradient of the mine waste is not of good quality. Most of the groundwater is acceptable for irrigation and all of it can be used for livestock. Keywords: Groundwater _ Acid mine drainage _ Sulphide tailings _ Lithology

Research paper thumbnail of Rhizosphere bacterial populations of metallophyte plants in heavy metal-contaminated soils from mining areas in semiarid climate

World Journal of Microbiology & Biotechnology, 2004

Rhizosphere bacterial populations associated with four metallophyte plants in one of major polyme... more Rhizosphere bacterial populations associated with four metallophyte plants in one of major polymetallic (Pb-Zn-Cu) semiarid Moroccan Hercynian province (DraaˆSfar, Marrakech, Morocco) presenting long-term contamination mainly with Zn and Pb were analysed and compared to selected control soils. In the highly Zn-, Cu-, Pb-and Cdcontaminated soils, the total number of culturable heterotrophic bacteria were found in low proportions (<2.6 · 10 2 -1.6 · 10 4 g )1 soil). This bacterial content was slightly similar to that found in moderately polluted and controls soils (6.7 · 10 4 -5.8 · 10 6 ). However, the bacterial diversity and the rhizosphere/soil ratio, which compares the bacterial content (or bacterial charge) around the metallophyte plants with that in non-rhizosphere soil, were the bacteriological parameters mostly affected by heavy metal contamination. The chronic Zinc-stress results in an increase of tolerance to this metal of both the rhizosphere and non-rhizosphere bacterial communities. However, in general, the rhizosphere bacterial populations exhibited less tolerance to Zn toxicity than the bacterial population of non-rhizosphere soils. This result suggests that toxic effects of Zn decrease in the rhizosphere soils of the metallophyte plants.

Research paper thumbnail of The hydrothermal system of Central Jebilet (Variscan Belt, Morocco): A genetic association between bimodal plutonism and massive sulphide deposits?

Journal of African Earth Sciences, 2008

Central Jebilet (Moroccan Variscan Belt) hosts several Cu and Pb-Zn massive sulphide deposits tha... more Central Jebilet (Moroccan Variscan Belt) hosts several Cu and Pb-Zn massive sulphide deposits that are associated with a suite of gabbroic and microgranitic, tholeiitic to alkaline, intrusions emplaced 330 Ma ago. The intrusions and ore bodies form structural lineaments within marine Visean shales that are affected by very low to low-grade post-Visean metamorphism and contemporaneous shortening accompanied by the development of conjugate ductile to brittle shear zones. The ductile shear zones are localised in thermally softened aureoles around magmatic intrusions, while brittle deformation is common far from the intrusions. The intrusions have induced a contact metamorphism that reaches the hornblende hornfels facies, and their emplacement was accompanied by hydrothermal activity that leached base metals from the felsic intrusions.

Research paper thumbnail of Interpretation of magnetic data of the Laachach gossan (central Jebilets, Morocco): mining implications

In the hercynian massif of Central Jebilets (Morocco), outcrop a large number of gossans which so... more In the hercynian massif of Central Jebilets (Morocco), outcrop a large number of gossans which sometimes top economical orebodies (Kettara, Draa Sfar, etc.). The present study is devoted to the interpretation of magnetic data covering one of these iron hats, located near of the Laachach village, at about thirty kilometres north-westward of Marrakech. The magnetic map of Laachach highlights several anomalies which coincide with the outcrop of the gossan. Detailed analysis of reduced to the pole data allows us to conclude that these anomalies may be due to submeridian magnetic structures cut by a set of dextral transverse faults. These structures are generally dipping westward but they can be locally sub vertical. The Euler deconvolution of the magnetic data gives moderately deeping solutions (22 to 254 m). The quantitative interpretation of the two principal magnetic anomalies highlighted in the study area lead to better characterising of the deep structure of the Laachach magnetic b...