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Geochemical, mineralogical and microbial modelling of an IOCG tailings deposit (El Buitre, Chile): implications for environmental safety and economic potential
(Universidad de Chile, 2022)
seleccionaron 98 para la caracterización de las comunidades microbianas. El tranque de relaves El Buitre presenta una mineralogía primaria caracterizada por un bajo contenido de pirita y calcopirita y un contenido relativamente alto de magnetita y hematita. La...
Tailings dams have become a focus of interest as possible alternative sources of raw materials to partially mitigate the shortages on many critical raw elements imposed by the always growing demand of technological applications and green energies. Additionally, they have become a serious environmental problem for the ecosystems that surround these artificial deposits. This work reports the results of a mineral, geochemical and microbial characterization study and geostatistical and conceptual modelling of an Iron Oxides Copper Gold deposit with neutral pH, in an arid climate. Twenty-eight boreholes allowed recovery of 755 samples for analysis. However, 98 were selected for the characterization of microbial communities. The El Buitre tailings dam presents a primary mineralogy characterized by low pyrite and chalcopyrite content with relatively high magnetite and hematite content. Gangue is dominated by quartz, chlorite, alkali-feldspar, plagioclase and calcite. Secondary sulfides such as chalcocite/digenite, enargite/tennantite and malachite/azurite can be considered negligeable. Climatic conditions limit the availability of water and restrict the mobility of metals under neutral pore water pHs, inhibit the development of extensive oxidation fronts and mineral enrichment zones and prevent the appearance of efflorescent salts precipitated on the tailings surface. Therefore, the distribution of the mineralogy and its associated elements are mainly controlled by the source deposit mineral composition, the mineral processing technology, gravitational deposition processes and the geometry of the tailings dam. Therefore, the low mobility of the polluting elements makes these deposits environmentally safe and with low contamination potential. Additionally, the depositional history of the tailings had a great influence on the vertical and horizontal distribution of pyrite. Nevertheless, the grades of economic interest elements such as Fe, Cu and Co are distributed in a relatively homogeneous way, which would facilitate the application of tailings reprocessing technologies and maximize the number of boreholes required for its economic evaluation. On the other hand, the structure and diversity of the microorganisms were determined by the slight variations in the chemical composition and the establishment of an oxidized and non-oxidized zone within the deposit of tailings. However, biomass and species richness remained practically constant with depth. The tailings core microbiome comprised the phylum Proteobacteria, Firmicutes, Actinobacteria, Nitrospirae and Deinoccocus-Thermus. The networking analysis suggests a mutualistic activity between bacteria and highlights the importance of the microbial dark matter in these complex ecosystems. The predicted functional presented slight variations associated with the stratification of the chemical composition. Finally, based on the functionality, distribution and mutualistic activity among the microorganisms, capabilities can provide a direction for the management of the tailings dam and maximize their potential for revalorization. Additionally, sulfate-reducing bacteria were used as bioindicators of redox conditions throughout the depth profile of the tailings deposit...
Tailings dams have become a focus of interest as possible alternative sources of raw materials to partially mitigate the shortages on many critical raw elements imposed by the always growing demand of technological applications and green energies. Additionally, they have become a serious environmental problem for the ecosystems that surround these artificial deposits. This work reports the results of a mineral, geochemical and microbial characterization study and geostatistical and conceptual modelling of an Iron Oxides Copper Gold deposit with neutral pH, in an arid climate. Twenty-eight boreholes allowed recovery of 755 samples for analysis. However, 98 were selected for the characterization of microbial communities. The El Buitre tailings dam presents a primary mineralogy characterized by low pyrite and chalcopyrite content with relatively high magnetite and hematite content. Gangue is dominated by quartz, chlorite, alkali-feldspar, plagioclase and calcite. Secondary sulfides such as chalcocite/digenite, enargite/tennantite and malachite/azurite can be considered negligeable. Climatic conditions limit the availability of water and restrict the mobility of metals under neutral pore water pHs, inhibit the development of extensive oxidation fronts and mineral enrichment zones and prevent the appearance of efflorescent salts precipitated on the tailings surface. Therefore, the distribution of the mineralogy and its associated elements are mainly controlled by the source deposit mineral composition, the mineral processing technology, gravitational deposition processes and the geometry of the tailings dam. Therefore, the low mobility of the polluting elements makes these deposits environmentally safe and with low contamination potential. Additionally, the depositional history of the tailings had a great influence on the vertical and horizontal distribution of pyrite. Nevertheless, the grades of economic interest elements such as Fe, Cu and Co are distributed in a relatively homogeneous way, which would facilitate the application of tailings reprocessing technologies and maximize the number of boreholes required for its economic evaluation. On the other hand, the structure and diversity of the microorganisms were determined by the slight variations in the chemical composition and the establishment of an oxidized and non-oxidized zone within the deposit of tailings. However, biomass and species richness remained practically constant with depth. The tailings core microbiome comprised the phylum Proteobacteria, Firmicutes, Actinobacteria, Nitrospirae and Deinoccocus-Thermus. The networking analysis suggests a mutualistic activity between bacteria and highlights the importance of the microbial dark matter in these complex ecosystems. The predicted functional presented slight variations associated with the stratification of the chemical composition. Finally, based on the functionality, distribution and mutualistic activity among the microorganisms, capabilities can provide a direction for the management of the tailings dam and maximize their potential for revalorization. Additionally, sulfate-reducing bacteria were used as bioindicators of redox conditions throughout the depth profile of the tailings deposit...
"Episodios metamórficos de muy bajo grado en rocas volcánicas básicas cenozoicas en Península Fildes, Isla King George, Islas Shetland del Sur, Antártica"
(Universidad de Chile, 2014)
tardío hasta la actualidad, sufriendo regímenes de compresión y extensión. En la península se depositaron en su mayoría lavas basálticas y andesítico-basálticas, brechas volcanoclásticas y tobas, asociados a dos episodios de actividad volcánica desde el...
Mineralización y alteración de la veta El Bronce, distrito El Bronce de Petorca, Región de Valparaíso, Chile
(Universidad de Chile, 2023)
, sericita, clorita y arcillas, y la mineralogía metálica a pirita, calcopirita, esfalerita, tennantita-tetrahedrita, galena, hematita y bornita. El oro ocurre mayoritariamente como partículas micrométricas de electrum en cristales de pirita. La composición...
Caracterización de las variables mineraralógicas del yacimiento El Soldado para identificar parámetros geometalúrgicos que afectan la recuperación de cobre
(Universidad de Chile, 2022)
la mineralización y ley de Cu mostrando una compleja respuesta metalúrgica.
La recuperación de cobre como respuesta metalúrgica es un parámetro cuantitativo que depende directa e indirectamente de la geología del yacimiento y es de gran importancia en...
Geología de los cuerpos de alta ley del sector La Unión inferior, yacimiento río Blanco, región de Valparaíso
(Universidad de Chile, 2015)
sobreimposición de la alteración sericita gris-verde (SGV) a la potásica (biotítica y feldespática) y su mineralogía de mena sulfurada hipógena evidencia una alteración transicional potásica-sericítica de alta temperatura (<550ºC). Sin embargo, en andesitas y...
Metodología de exploración minera mediante espectrometría de reflectancia en sedimentos activos fluviales: Cuenca del Río Limarí, IV Región, Chile
(Universidad de Chile, 2013)
espectrometría de reflectancia de los sedimentos y su geoquímica, para de esta forma, lograr generar una herramienta de prospección que anticipe los resultados químicos y que sea una guía para prospección geoquímica.
Se determinó el espectro de reflectancia de la...
Búsqueda de volátiles en cuerpos parentales asteroidales mediante estudio de inclusiones vítreas, espectroscopía Raman y espectroscopia de absorbancia en condritos ordinarios
(Universidad de Chile, 2023)
El curso de “Fluidos Planetarios” del Departamento de Geología de la Universidad de
Chile, realizó una expedición de búsqueda y recolección de meteoritos, en las inmediaciones
de Taltal (Desierto de Atacama, Región de Antofagasta), entre el 31 de...
Respuesta geoquímica en una cubierta aluvial sobre un pórfido cuprífero: Quebrada de los Arrieros, Región de Antofagasta, Chile
(Universidad de ChilePrograma Cybertesis, 2007)
en las gravas que cubren el pórfido cuprífero Arrieros, y 174 muestras de suelo sobre un área prospectiva en la que se desconoce la existencia de algún cuerpo tipo pórfido mineralizado bajo superficie. Se aplicó el método de extracción parcial Agua...
Scaling en la central geotérmica Cerro Pabellón, norte de Chile: Química, mineralogía y modelo geoquímico
(Universidad de Chile, 2023)
barrido para identificar la mineralogía, química y texturas de los precipitados sólidos. Adicionalmente, se realizó un modelamiento geoquímico con los softwares PhreeqC y The Geochemist's Workbench para validar los procesos termodinámicos y evaluar la...
Contribución a la Geocronología y Geoquímica de los Intrusivos Estero Yerba Loca y Batolito San Francisco, Cordillera de Chile Central. (33°S)
(Universidad de Chile, 2007)
feldespato, con mineralogía accesoria de circón, turmalina y esfeno, y
actinolita como mineral de alteración en piroxenos.
Se dataron las muestras mediante el método U-Pb en circón. Las muestras datadas entregan dos
edades características una alrededor ~15 Ma...