DSpace Collection:
http://hdl.handle.net/10174/176
2024-03-17T12:52:49ZGeomorfologia,sedimentologia e datação absoluta de unidades sedimentares da zona costeira de Portugal central relevância para riscos naturais e desafios societais
http://hdl.handle.net/10174/24685
Title: Geomorfologia,sedimentologia e datação absoluta de unidades sedimentares da zona costeira de Portugal central relevância para riscos naturais e desafios societais
Authors: Gouveia, Margarida; Cunha, Pedro; Felguéres, Christophe; Martins, António
Abstract: Os terraços costeiros e os situados nos troços inferiores de importantes rios são arquivos terrestres de importantes regiões do Globo que permitem documentar as mudanças ambientais durante períodos de alto nível do mar e as mudanças climáticas ocorridas durante o Plistocénico.2017-07-02T23:00:00ZGEOQUÍMICA DE ELEMENTOS MAIORES EM SEDIMENTOS DE BARRAGENS DOMINICANAS: ANÁLISE DA SUA PROVENIÊNCIA
http://hdl.handle.net/10174/22565
Title: GEOQUÍMICA DE ELEMENTOS MAIORES EM SEDIMENTOS DE BARRAGENS DOMINICANAS: ANÁLISE DA SUA PROVENIÊNCIA
Authors: Araújo, Joana; Nogueira, Pedro; Fonseca, Rita; Pinho, Catarina; Araújo, António
Abstract: The climatic conditions of Dominican Republic are conducive to the existence of high erosion rates, which may represent high sedimentation rates, that can make the dams silted. It is intended to do a geochemical characterization of the dam’s sediments, in order to study the sedimentary processes of the drainage basins. Through the analysis of the sediments of the bottom of two dam reservoirs (Tavera and Sabana Yegua) and the soils from the drainage basins, we intend to make a comparative geochemical analysis to identify the main sources of the sedimentary material of each dam. This study corresponds to a preliminary approach, which consists of the analysis of major elements by ICP-OES, in an attempt of identifying the sediments provenance.2018-01-01T00:00:00ZEvaluation of the Environmental Risk of Contaminated Materials in the Alluvial Plain of a Metallurgical Unit
http://hdl.handle.net/10174/22516
Title: Evaluation of the Environmental Risk of Contaminated Materials in the Alluvial Plain of a Metallurgical Unit
Authors: Pinho, Catarina; Fonseca, Rita; Carneiro, Júlio
Abstract: Anthropogenic occurrence of metals in a natural environment is mainly related to the existence and functioning of industrial activities. The Três Marias metallurgical unit of Votorantim Metais S.A., located in the Brazilian state of Minas Gerais, has been producing zinc alloys since the late 1960's. Its operation has caused several environmental impacts in its surroundings, namely soils, sediments and water quality. The geochemical characterization of this area revealed a high contamination in heavy metals (cadmium, chromium, copper, manganese, nickel, lead and zinc) and arsenic, above the critical levels, most of which having high bioavailability.
This study aims to evaluate and discuss the extent of contamination in the alluvial plain of Consciência waterway, a tributary of the São Francisco river, through geochemical analysis of the sediments and water column, in order to evaluate the most appropriate environmental remediation technique(s) to Implement in the area2017-11-01T00:00:00ZSampling and analytical methods for the geochemical study of the sediment of reservoirs in the Dominican Republic: preliminary results
http://hdl.handle.net/10174/22507
Title: Sampling and analytical methods for the geochemical study of the sediment of reservoirs in the Dominican Republic: preliminary results
Authors: Araújo, Joana; Nogueira, Pedro; Fonseca, Rita; Pinho, Catarina; Araújo, António
Abstract: This paper characterizes the geochemical profile of the sediments of two dam reservoirs from the Dominican Republic focusing on the sedimentary processes involved and on determining the main sources of the deposited material. Surface and deep sediments were sampled as well as rocks of the drainage basins in order to compare geochemical signatures of the parent rock and of the materials deposited at the bottom of the two dams. This study comprises a geochemical analysis of major, minor, trace and rare earth elements. A petrographic analysis of the different lithotypes was carried out. The preliminary geochemical analysis of sediments showed high Ca and Mg content levels, demonstrating the important influence of the carbonate rocks, present on the basin, to the sedimentation processes.2017-11-01T00:00:00Z