Geochemical Mobility Associated to Gold and Base Metal Occurrences of Mangodara Sector, in Southern Burkina Faso, Banfora Greenstone Belts (West African Craton)  

作　　者：Bernadin Gnamou Hermann Ilboudo Wilfried Antoine Bassou Toé Sâga Sawadogo Bernadin Gnamou;Hermann Ilboudo;Wilfried Antoine Bassou Toé;Sâga Sawadogo(Laboratoire Géosciences et Environnement (LaGE), Département des Sciences de la Terre, Ouagadougou, Burkina Faso)

机构地区：[1]Laboratoire Géosciences et Environnement (LaGE), Département des Sciences de la Terre, Ouagadougou, Burkina Faso

出　　处：《Open Journal of Geology》2023年第10期1024-1053,共30页地质学期刊（英文）

摘　　要：In the Mangodara area within the Banfora greenstone belts (Baoulé-Mossi domain of the West African Craton), our study focused on geochemical assessment of the mobility of major and trace elements. Gold and base metal occurrences are hosted in highly metamorphic felsic (metarhyolite) and intermediate (metadacite and metaandesite) formations. Common mineral assemblages made up of staurolite - kyanite - pyrophyllite are interpreted to represent the metamorphosed equivalent of aluminous hydrothermal alteration. Associated felsic and intermediate volcanic rocks are enriched in Fe₂O₃, K₂O (metaandesite, metarhyolite) and depleted in MgO, Al₂O₃, CaO, P₂O₅, Na₂O (metarhyolite) and Fe₂O₃, MgO, CaO (metaandesite). Al₂O₃ depletion in mineralized kyanite-staurotide bearing metarhyolites suggests corroded minerals. Mineralized metarhyolites show enrichment in Au, Ag, Ba, Bi, Cr, Cu, Eu, La, Mo, Ni, Pb, S, Sc, V and depletion in As Sb Co, Sn, Zn while mineralized metaandesites show enrichment in Au, Ag, As, Mo, S, Sb and depletion in Co, Sn, Zn, Bi, Cr, Cu, Eu, Ni, Pb, Sc. Ba, La, V are immobile in metaandesites. Finally, Ag, As, Sn appear as geochemical vectors for gold exploration in the study area since gold mineralization is characterized by Au + Ba + Cu + Eu + La + Mo + Ni + S association in metarhyolites and Au + S + Sb + As + Ag + Bi in metaandesites.In the Mangodara area within the Banfora greenstone belts (Baoulé-Mossi domain of the West African Craton), our study focused on geochemical assessment of the mobility of major and trace elements. Gold and base metal occurrences are hosted in highly metamorphic felsic (metarhyolite) and intermediate (metadacite and metaandesite) formations. Common mineral assemblages made up of staurolite - kyanite - pyrophyllite are interpreted to represent the metamorphosed equivalent of aluminous hydrothermal alteration. Associated felsic and intermediate volcanic rocks are enriched in Fe₂O₃, K₂O (metaandesite, metarhyolite) and depleted in MgO, Al₂O₃, CaO, P₂O₅, Na₂O (metarhyolite) and Fe₂O₃, MgO, CaO (metaandesite). Al₂O₃ depletion in mineralized kyanite-staurotide bearing metarhyolites suggests corroded minerals. Mineralized metarhyolites show enrichment in Au, Ag, Ba, Bi, Cr, Cu, Eu, La, Mo, Ni, Pb, S, Sc, V and depletion in As Sb Co, Sn, Zn while mineralized metaandesites show enrichment in Au, Ag, As, Mo, S, Sb and depletion in Co, Sn, Zn, Bi, Cr, Cu, Eu, Ni, Pb, Sc. Ba, La, V are immobile in metaandesites. Finally, Ag, As, Sn appear as geochemical vectors for gold exploration in the study area since gold mineralization is characterized by Au + Ba + Cu + Eu + La + Mo + Ni + S association in metarhyolites and Au + S + Sb + As + Ag + Bi in metaandesites.

关 键 词：Geochemical Mobility Aluminous Alteration METAMORPHISM GOLD Base Metal Banfora Greenstone Belts Mangodara 

分 类 号：P59[天文地球—地球化学]