Caracterização e proveniência dos materiais de construção e dos fragmentos cerâmicos do povoado da idade do ferro do Outeiro do Castro da Bóca (Vila Nova de Famalicão)

O Outeiro do Castro da Bóca é um pequeno povoado fortificado, localizado na união de freguesias de Vale de São Cosme, Telhado e Portela, do concelho de Vila Nova de Famalicão, distrito de Braga, com as seguintes coordenadas: Latitude N41°27’25’’ e Longitude W 8°28’36’’. O que resta deste povoado, parcialmente destruído pela exploração de saibro para a construção da A3, permite caracterizá-lo como um pequeno povoado constituído por uma plataforma central, com duas pequenas plataformas adossadas a Oeste; o sistema defensivo, bem visível a NW, é composto por uma linha de muralha protegida por um fosso. Os trabalhos arqueológicos em curso, desde 2004, permitiram pôr a descoberto duas fases de ocupação. Estas distinguem-se pelo tipo de construções realizadas e pelo tipo de materiais que lhe estão associados possibilitando afirmar que o povoado, terá́ sido ocupado entre o séc. IV a.C. e o séc. I a.C. As amostras estudadas correspondem à primeira fase de ocupação. O objectivo do trabalho é caracterizar e identificar a potencial matéria-prima utilizada como material de construção do povoado, no Outeiro de Castro da Bóca e caracterizar os fragmentos cerâmicos de tachos de asa interior, tendo em vista a sua proveniência.This work was co-funded by the EU, based on COMPETE 2020, project ICT (UID/GEO/04683/2013), reference POCI-01-0145-FEDER-007690, national funds provided by FC

Thorium and Uranium distribution in a passive system for mine water treatment

The abandoned Jales mining area is a sulphide-rich deposit (Northeast of Portugal). Acid mine drainage resulted from oxidation of sulphides is treated in a passive system with wetlands. The present work studies the thorium and uranium behaviour in the water and in the fine fractions of wetland soils throughout the passive treatment system. The evaluation of the efficiency of the all system was done determining metals concentration variation in the creek water upstream and downstream of the treated effluent discharge. The results point to higher efficiency to retain Th after summer than after winter. The opposite was found for uranium, which increases significantly in the creek water after summer and, in a lower extent, after winter. Also, Th and U have a tendency to increase in the fine fractions of the wetlands soils after summer, which can be explained by the longer water-soil contact/lower water dynamics. Nevertheless uranium has a much higher tendency to be in solution as revealed by a high concentration in the porewater of wetland soils. A relation of these actinides behaviour with the Fe and Mn distribution is not clear.- Thanks are given to EDM, S.A. for providing access to the water treatment plant, FCT (Portuguese Science and Technology Foundation, UID/Multi/04349/2013, and COMPETE 2020 (Programa Operacional da Competitividade e Internacionalizacao), project ICT (UID/GEO/04683/2013) with reference POCI-01-0145-FEDER-007690 and project Nano-MINENV number 029259

Metals and arsenic enrichment processes in sulfide-rich waste dumps - the role of the clay size fraction

[Extract] 1. Purpose Abandoned mines pose some of the most outstanding environmental risks, namely related with potentially toxic metals and metalloids in mining soils. Mobilization or fixation of these elements in the soil particles can be regulated by the interactions between several biogeochemical and mineralogical processes. In this context, the present study is focused on the detection of metals and arsenic enrichment processes in different particle size fractions of two distinctive sulphide-rich waste dumps. Furthermore, the study evaluates the role of typical clay size minerals, such as oxyhydroxides and clay minerals in the retention of toxic elements...info:eu-repo/semantics/publishedVersio

Origem dos filmes negros sobre património construído: diversos olhares

Os filmes negros desenvolvem-se sobre substrato granítico com morfologia idêntica ao mesmo. A sua eliminação requer métodos abrasivos e/ou químicos por forma a superar a impermeabilidade e dureza característica. A génese de formação dos filmes negros é o elemento fundamental para contribuir para a preservação e sustentabilidade do património construído granítico na perspectiva de minimizar o seu desenvolvimento. A composição dos filmes foi estudada mineralógica, química e biologicamente através da aplicação de técnicas analíticas como MEV-EDE, DRX e técnicas tradicionais de microbiologia. Finalmente, os resultados da pirólise analítica (Py-GC/MS) confirmaram os dados obtidos anteriormente.FC

Biogeochemistry of household dust samples collected from private homes of a portuguese industrial city

The main objectives of the present study were to (i) investigate the effects of mineralogy and solid-phase distribution on element bioaccessibility and (ii) perform a risk assessment to calculate the risks to human health via the ingestion pathway. Multiple discriminant analysis showed that the dust chemistry discriminates between indoor and outdoor samples. The solid-phase distribution of the elements in indoor dust indicated that a large proportion of zinc, nickel, lead, copper, and cobalt is associated with an aluminum oxy-hydroxides component, formed by the weathering of aluminum silicates. This component, which seems to influence the mobility of many trace elements, was identified for a group of indoor dust samples that probably had a considerable contribution from outdoor dust. An iron oxide component consisted of the highest percentage of chromium, arsenic, antimony, and tin, indicating low mobility for these elements. The bioaccessible fraction in the stomach phase from the unified BARGE method was generally high in zinc, cadmium, and lead and low in nickel, cobalt, copper, chromium, and antimony. Unlike other potentially toxic elements, copper and nickel associated with aluminum oxy-hydroxides and calcium carbonates were not extracted by the stomach solutions. These trace elements possibly form stable complexes with gastric fluid constituents such as pepsin and amino acid. Lead had a hazard quotient >1, which indicates the risk of non-carcinogenic health effects, especially for children.This research was by funded the LabexDRIIHM,Frenchprogramme“Investissementsd’Avenir”(ANR‐11‐LABX‐0010) which is managed by the ANR, and co‐funded by the European Union through the European Regional Development Fund, based on COMPETE 2020 (Programa Operacional da Competitividade e Internacionalização), projects ICT UIDB/04683/2020 and UIDP/04683/2020, project GeoBioTec (UID/GEO/04035/2019) and national funds provided by the FCT ‐ Fundação para a Ciência e a Tecnologia,I.P

Mineralogical attenuation processes associated with the evolution of acid mine drainage in sulfide-rich mine wastes

The geochemical evolution of acid mine drainage results in secondary minerals that play a key role in the environmental behavior of the mine wastes. The present work is focused on these newly formed minerals at the Penedono waste dump, characterized by fine-grained tails with pyrite and arsenopyrite. Mineralogical study led to an inventory of secondary phases, comprising soluble sulfates, scorodite, and oxyhydroxysulfates. In addition, there is amorphous Fe, As rich-nanoprecipitates. Jarosite and scorodite are abundant minerals, acting as cement for encrusting tails in Fe and As-rich hardpans. These hard structures are relatively insoluble, retaining toxic elements, thereby contributing to natural attenuation of mining contamination associated with the sulphide wastes.European Union through the European Regional Development Fund, based on COMPETE 2020 - project ICT (UID/GEO/04683/2013) with reference POCI-01-0145- FEDER-007690 and project Nano-MINENV number 02925

Hydrochemistry, elements distribution and their potential recoveries in gold metallurgical treatment tailings dams

Wastewaters are valuable sources of metals and metalloids and can serve as essential resources for their recovery. Characterizing and understanding the occurrence of metals and other compounds, along with identifying the most effective recovery methods, are key steps in unlocking the potential for reusing these resources. The present study focused on analyzing waters from various mining dams in the Iron Quadrangle (IQ) region of Brazil, which contained metals such as Au, Cu, Ni, Zn, and sulfates resulting from the metallurgical treatment of Au. The results revealed a range of metal concentrations in the neutral zone in three tailings. Additionally, a 3D map was created, and a statistical analysis and an exploration of the processes governing mobility and partitioning were conducted to assess the potential for reuse. Notably, the study identified a high potential for Au recovery, particularly through the utilization of sustainable and cost-effective methods such as nanofibers with biosorbents. Overall, this research contributes to the understanding and exploration of potential reuse procedures for strategic metals in various industrial applications.This research was funded by Fundação para a Ciência and Tecnologia (FCT) through projects UIDB/04683/2020, UIDP/04683/2020, and Nano-MINENV 029259 (PTDC/CTA-AMB/ 29259/2017)

Caracterização e proveniência dos materiais de construção e dos fragmentos cerâmicos do povoado da Idade do Ferro do Outeiro do Castro da Bóca (Vila Nova de Famalicão)

Levantamentos geológicos, amostragem e caracterização do material de construção, dos materiais cerâmicos e da matéria-prima do povoado da Idade do Ferro de Outeiro de Castro da Bóca (concelho de Vila Nova de Famalicão)info:eu-repo/semantics/draf

Limestones under salt decay tests: assessment of pore network-dependent durability predictors

Three Portuguese limestones (two grainstones, Semi-rijo and Moca Creme commercial types, and a trav-ertine) were subjected to salt crystallisation test (EN 12370:1999). Grainstones specimens showed higher weight loss than the travertine ones. Results are discussed, using parametric and nonparametric statistics, in relation to pore space characteristics that have been considered durability predictors, evaluated at the macroscopic (water imbibition) and microscopic (mercury injection porosimetry) levels. Several of the pore-space parameters indicate differences between grainstones and travertine, but these differences are much lower than the differences in weight loss. Results of the durability dimensional estimator (DDE) seem to present a discrepancy, with higher values in the rock type having lower weight loss (travertine). Additionally, weathering patterns of travertine samples show marked irregularities (a feature that is not assessed by weight loss). These irregularities are attributed to heterogeneous spatial distribution of detritic components (a feature that is not assessed by pore-space parameters). Comparing the grain-stones, Moca Creme showed higher values of mass loss and several durability predictors suggested noteworthy differ-ences in relation to Semi-rijo. However, these differences are much lower than differences in weight loss. Calculated crystallisation pressures are even higher for Semi-rijo. It is proposed that petrographical aspects of Moca Creme, namely heterogeneity related to the presence of bioclasts and veinlets, could contribute to explain the higher weathering susceptibility of this rock type. These results highlight the need to include petrographical features in assessments of durability and the usefulness of visual description on the characterization of salt weathering.Fundação para a Ciência e a Tecnologia (FCT)Acknowledgments This research was developed in the scope of the Project PORENET (POCTI/CTA/44940/2002). This project and the research units involved receive support from Fundação para a Ciência e a Tecnologia (FCT) funded by the European Union (FEDER) and the national budget of the Portuguese Republic. Acknowledgments are also due to Eng. Teresa Luís, Eng. Sónia Pereira and the Enteprise Mármores Galrão for the initial blocks for the specimen extraction

Mineralogía de los sedimentos de embalses afectados por drenaje ácido de mina en el sector español de la Faja Pirítica Ibérica

The Iberian Pyrite Belt (IPB), in southwestern of Spain, allocates 23 reservoirs dams along its fluvial network, built for industrial, mining, agriculture and/or recreation. These dams are affected by acid main drainage (AMD), presenting different degrees of contamination. The weathering of sulphides, mainly in the mine waste dumps, promoted the release of pollutants, such a sulphate and metals, which suffer transport into the water dams. The present work documents the mineralogy of different grain size fractions (<2 mm and <2 μm fractions) of the water dam’s sediments. The mineralogical results obtained by X-ray diffraction were combined with geochemical data, namely through determination of accumulation factors for some toxic elements. The obtained results indicate that contamination of the sediments is regulated by many factors, such as mineralogical composition of fine fraction and the presence of sorption sites on specific mineral phases. Thus, iron oxyhydroxides and iron hydroxysulfates are important components of the clay mineral fraction, controlling the retention of toxic elements, especially in the mining dams.En la Faja Pirítica Ibérica, SW de España, hay 23 embalses distribuidos por la red fluvial, que han sido construidos para uso agrícola, industrial, minero y/o para abastecimiento de las poblaciones. Estos embalses presentan distintos grados de afección por drenaje ácido de mina, resultante de la meteorización de los sulfuros presentes en las estructuras mineras de la Faja. Los contaminantes movilizados por el proceso de drenaje ácido de mina son transportados por los cauces como materia disuelta y en suspensión hacia los embalses, donde se acumulan en sus sedimentos. El presente trabajo documenta la mineralogía de diferentes fracciones granulométricas (<2 mm y <2 μm) de los sedimentos de los embalses. Los resultados de la mineralogía obtenidos por difracción de rayos-X fueran combinados con datos de geoquímica, permitiendo el calcular factores de acumulación para algunos elementos tóxicos. Los resultados obtenidos indican que la contaminación de los sedimentos es controlada por factores, tales como la composición mineralógica de la fracción más fina y la presencia de sitios de adsorción en la superficie de fases minerales específicas. Así, oxihidróxidos de hierro y oxihidroxisulfatos de hierro son importantes componentes de la fracción <2 μm, controlando la retención de elementos tóxicos, principalmente en los embalses mineros.info:eu-repo/semantics/publishedVersio