65 documents found, page 1 of 7
Evaluation of the level of contamination in sediments from watercourses of the ...
Silva, R.; Fonseca, R.; Araújo, J.; Silva, N.; Albuquerque, T.The following work is inserted in the GeoMatRe Project, in which the conditions of the most updated physical and chemical parameters of an Acid Mine Drainage are analysed. This study shows that the mining area of Caveira, in Grândola, Portugal, which was abandoned since the 60’s, presents a critical situation of contamination, with high levels of Potentially Toxic Elements (PTE) present in the whole mining area...
Geochemistry of Soils from the Surrounding Area of a Coal Mine Waste Pile Affec...
Santos, P.; Espinha Marques, J.; Ribeiro, J.; Mansilha, C.; Melo, A.; Fonseca, R.; Sant'Ovaia, H.; Flores, D.Coal mining can generate organic and inorganic pollutants that can be disseminated in the sur-rounding soils by leaching and/or aerial deposition. This study aims to identify and characterize the physicochemical and geochemical changes, promoted in the soils that surround a self-burning waste pile from an abandoned coal mine. A soil geochemical campaign was conducted bordering the waste pile, comprising the mai...
Geochemistry and Mineralogy of Auriferous Tailings and Their Potential for Reus...
Lemos, M.; Valente, T.; Marinho Reis, P.; Fonseca, R.; Pantaleão, J.P.; Guabiroba, F.; Gregorio Filho, J.; Magalhães, M.; Afonseca, B.; Silva, A.R.Since the mid-nineteenth century, gold ores, mainly hosted in sulfides, have been processed at metallurgical plants located in Nova Lima, Brazil. The generated wastes have been accumulated over the years in tailings dams or in piles. These materials represent wasted from old circuits, as well as from plants still in production. In this study, geochemical, mineralogical, 3D modelling, and metallurgical analyses ...
Adding Value to Mine Waste through Recovery Au, Sb, and As: The Case of Aurifer...
Lemos, M.; Valente, T.; Marinho Reis, P.; Fonseca, R.; Guabiroba, F.; Mata Filho, J.G.; Magalhães, M.F.; Delbem, I.D.; Rebelo Diório, G.From the colonial era to modern times, gold mining has played a crucial role in shaping Brazil’s economy, culture, and landscape, particularly in the Iron Quadrangle region. Therefore, resulting waste has accumulated in tailings structures, either from deactivated circuits or plants still in production. The present study reveals the potential assessed based on a set of metallurgical tests, assuming specific sce...
Hydrochemistry, Elements Distribution and Their Potential Recoveries in Gold Me...
Lemos, M.; Valente, T.; Marinho Reis, P.; Braga, A.S.; Fonseca, R.; Guabiroba, F.; Mata Filho, J.G.; Magalhães, M.F.; Silva, A.R.; Bhering, A.P.Recovering metals from mining wastewater is important in minimizing environmental pollution and maximizing resource efficiency. For this, a characterization step and understanding the oc-currence of metals and other compounds are essential. The present study focused on waters from different mining dams containing metals such as Au, Cu, Ni, Zn, and sulfates, located in the Iron Quadrangle region, (Brazil). The r...
Sensitivity analysis and pre-feasibility of reprocessing Au from a tailings dam...
Lemos, M.; Valente, T.; Marinho Reis, P.; Fonseca, R.As historical waste has accumulated in dams, the interest in studying the feasibility of reusing mining tailings has grown, offering both environmental and economic advantages. However, given the unique characteristics of each site, conducting site-specific assessments is crucial. Building on a detailed evaluation of the Cocoruto Dam in Nova Lima, Minas Gerais, this study presents a technical feasibility and fi...
Stream sediments pollution: a compositional baseline assessment
Albuquerque, T.; Fonseca, R.; Araújo, J.; Mota Silva, N.; Araújo, A.A high concentration of potentially toxic elements (PTEs) can affect ecosystem health in many ways. It is therefore essential that spatial trends in pollutants are assessed and monitored. Two questions must be addressed when quantifying pollution: how to define a non-polluted sample and how to reduce the problem’s dimensionality. A geochemical dataset is a composition of variables (chemical elements), where the...
Hydrogeochemistry of Surface Waters in the Iron Quadrangle, Brazil: High-Resolu...
Vicq, R.; Leite, M.G.P; Leão, L.; Nalini Júnior, H.A.; Cunha e Silva, D.C.; Fonseca, R.; Valente, T.The assessment of sediment contamination is a critical component in understanding the dynamics of potentially toxic elements (PTEs) in aquatic ecosystems, particularly in regions with intensive mining activities. This study focuses on the Rio das Velhas basin, located in the Iron Quadrangle (IQ), one of the most important mining provinces in the world, characterized by extensive anthropogenic pressures and rich...
Advancing the Understanding of Sediment Contamination Dynamics in the Iron Quad...
Vicq, R.; Leite, M.G.P; Leão, L.; Nalini Júnior, H.A.; Gomes, P.; Fonseca, R.; Valente, T.The assessment of sediment contamination is a critical component in understanding the dynamics of potentially toxic elements (PTEs) in aquatic ecosystems, particularly in regions with intensive mining activities. This study focuses on the Rio das Velhas basin, located in the Iron Quadrangle (IQ), one of the most important mining provinces in the world, characterized by extensive anthropogenic pressures and rich...
Ordovician – Silurian transition in the Central-Iberian Zone: Just a stratigrap...
Tereso, V.; Dias, R.; Roseiro, J.; Romão, J.; Coke, C.; Fonseca, R.; Ribeiro, A.The Ordovician-Silurian boundary in the Central-Iberian Zone is often considered a normal stratigraphic transition. Nevertheless, in studies carried out in Portugal (e.g. Espinhosela, São Mamede and Buçaco areas) and Spain (e.g. Alcañices Synform) this contact is marked by the development of shear zones subparallel to the lithostratigraphic units. Ongoing structural mapping in Celorico de Basto (Marão region) s...