The Saghro massif constitutes a vast metallogenic province with numerous deposits and shows of base metals (lead, zinc, copper) and precious metals (gold and silver), besides various useful substances (talc, pyrophyll...The Saghro massif constitutes a vast metallogenic province with numerous deposits and shows of base metals (lead, zinc, copper) and precious metals (gold and silver), besides various useful substances (talc, pyrophyllite, barite, fluorite). Silver/lead occurrences are concentrated along the Cryogenian Imiter series and moderately at Boumalne and Sidi Flah. Copper occupies the plutonic intrusions and intrusive rocks of the East-Central Saghro while barite deposits are widespread throughout the Cambrian cover of the East Saghro in contact with the Ediacaran basement. To justify this distribution, the new contributions of the cartography and the organic geochemistry of the black shales of Jbel Saghro have clearly shown the particularity of the Imiter black shales in terms of the richness in organic matter (TOC = 0.18%), the blackish color and the friability. The Boumalne and Sidi Flah groups present some similarities with the Imiter group, such as the sub-equatorial structuring, the friable pelites and the richness in organic matter (Boumalne TOC = 0.11% and SidiFlah TOC = 0.16%), which is a quite good show that requires to reinforce the exploration works. For Western Saghro in the Iknioun and Qalaa’t M’Gouna groups, the variations in the thickness of the volcanic cover show an irregular paleotopography with hard, greenish, organic-poor pelitic sediments (TOC = 0.01 to 0.04%). We can conclude that the formation of Imiter-type silver concentrations requires the combination of the sedimentological, the volcanic and structural factors. For Imiter-type silver these factors are: a fine pelitic and argillic casing deposited in a confined environment, a basic volcanism source of metals and other intermediate to acid generated by the hydrothermalism and heat, a convenable paleotopography and a network of fracturations to trap the mineralizations.展开更多
Extraction of mineral resources is the backbone of the national economy in many developed and developing countries of the world. However, the exploitation can have many negative impacts on the immediate environment of...Extraction of mineral resources is the backbone of the national economy in many developed and developing countries of the world. However, the exploitation can have many negative impacts on the immediate environment of the exploitation sites. In this study performed on some mining areas of the Moroccan Anti-Atlas, four principal negative effects were detected: effect on the physiognomy, on safety, on health, and on recovery rate. The principal source of this situation is the exploitation of the ore deposits from top to bottom without using any geological preparation and the use of non-adapted exploitation technics. To minimize these impacts, we propose to establish a geological study and advanced mining exploration before starting exploitation, and follow an exploitation technic well adapted to the morphology of the ore deposit like cut-and-fill mining and sublevel stoping methods.展开更多
文摘The Saghro massif constitutes a vast metallogenic province with numerous deposits and shows of base metals (lead, zinc, copper) and precious metals (gold and silver), besides various useful substances (talc, pyrophyllite, barite, fluorite). Silver/lead occurrences are concentrated along the Cryogenian Imiter series and moderately at Boumalne and Sidi Flah. Copper occupies the plutonic intrusions and intrusive rocks of the East-Central Saghro while barite deposits are widespread throughout the Cambrian cover of the East Saghro in contact with the Ediacaran basement. To justify this distribution, the new contributions of the cartography and the organic geochemistry of the black shales of Jbel Saghro have clearly shown the particularity of the Imiter black shales in terms of the richness in organic matter (TOC = 0.18%), the blackish color and the friability. The Boumalne and Sidi Flah groups present some similarities with the Imiter group, such as the sub-equatorial structuring, the friable pelites and the richness in organic matter (Boumalne TOC = 0.11% and SidiFlah TOC = 0.16%), which is a quite good show that requires to reinforce the exploration works. For Western Saghro in the Iknioun and Qalaa’t M’Gouna groups, the variations in the thickness of the volcanic cover show an irregular paleotopography with hard, greenish, organic-poor pelitic sediments (TOC = 0.01 to 0.04%). We can conclude that the formation of Imiter-type silver concentrations requires the combination of the sedimentological, the volcanic and structural factors. For Imiter-type silver these factors are: a fine pelitic and argillic casing deposited in a confined environment, a basic volcanism source of metals and other intermediate to acid generated by the hydrothermalism and heat, a convenable paleotopography and a network of fracturations to trap the mineralizations.
文摘Extraction of mineral resources is the backbone of the national economy in many developed and developing countries of the world. However, the exploitation can have many negative impacts on the immediate environment of the exploitation sites. In this study performed on some mining areas of the Moroccan Anti-Atlas, four principal negative effects were detected: effect on the physiognomy, on safety, on health, and on recovery rate. The principal source of this situation is the exploitation of the ore deposits from top to bottom without using any geological preparation and the use of non-adapted exploitation technics. To minimize these impacts, we propose to establish a geological study and advanced mining exploration before starting exploitation, and follow an exploitation technic well adapted to the morphology of the ore deposit like cut-and-fill mining and sublevel stoping methods.
