The salitre cave karst in the quartzite rocks of diamantina, Minas Gerais, Brazil

National audienceThis work presents the main morphological characteristics of the Salitre Cave, located in the municipal district of Diamantina - MG and formed in quartzite rocks of the Espinhaço Supergroup, Sopa-Brumadinho Formation as an example of a well-developed karst system. This system now supported by two to three independent small seasonal rivers and displays well-developed dissolution and breakdown structures, as a result of intense intemperance activity. This karst formed, probably before the beginning of Quaternary taking advantage of a system of fractures, normal and thrust faults caused by Espinhaço and Brasiliano events in the Middle to Late-Cambrian. This work attempts at presenting an integrated view of the investigated area and at emphasizing its importance for the understanding of the processes, which occurred in the in carbonatic, quartzitic and silico-carbonatic rocks of Rio San Francisco and Rio Jequitinhonha Basins among the chain of the Espinhaço Range on east and the river valley of San Francisco on the west

A qualidade ambiental da água do rio São Francisco entre o lago de Três Marias e o distrito de Barra do Guaicui-MG/foz do rio das Velhas: parâmetros físico-químicos

Este trabalho visa investigar a qualidade ambiental da água superficial do Rio São Francisco no segmento entre o lago de Três Marias a confluência com o Rio das Velhas/ Distrito da Barra do Guaicuí. Para a realização deste, foram utilizados os procedimentos metodológicos: revisão bibliográfica e cartográfica; seleção dos pontos de amostragem em gabinete e in situ (54 pontos); trabalhos de campo e análises físicoquímicas dos parâmetros: pH, Oxigênio Dissolvido, Condutividade Elétrica, Turbidez, Temperatura, in situ. A interpretação dos dados apontou algumas alterações em determinados parâmetros da qualidade ambiental da água no Rio São Francisco. Estas alterações foram associadas às questões naturais, a ação antrópica e em determinados momentos a correlação entre ambas. Dentre as questões naturais, destacam-se as especificidades litológicas, geomorfológicas, pedológicas, climáticas e a morfologia do canal fluvial, já as ações antrópicas, destacam-se o lançamento de efluentes industriais, domésticos, urbanos e uso de agroquímicos. Apesar de vários parâmetros analisados se encontrarem dentro dos padrões, é relevante o monitoramento destes pontos, uma vez que variam de forma acelerada, no tempo e no espaço físico

Use of Si-Phytoliths in depollution of mining areas in the Cerrado-Caatinga region, MG, Brazil

International audienceTreating of metal contaminated areas became a very important problem with increasing industrial and agricultural activities. Many of the used methods are very expensive, need intensive human interaction or have a very negative influence on the cleaned regions. The use of Si-Phytolites is a simple, low cost and a very effective way to obtain good results in low contaminated or as the final process in highly contaminated places. The method is based on the fact that a lot of plants produce Si-Phytolits and trap significant quantities of heavy metals in these amorphous to microcrystalline structures. The solubility of the Si-Phytolits under Brazilian soil conditions is lower than that of the heavy elements brought directly in the soil by the wash or fall out, or by degrading of organic parts of the plants at the upper part of surface. In this way, it is possible to retain liberation to the environment from short to longer periods and attend environmental laws and norms.Initial tests with different plants like Ricinus comunis L., Andropogon arundinaceus Willd., Zea Mays L., Brachiaria sp. L. and Saccharum officinarum L. planted on substrates with metal concentrations (Al, Fe, Mn, Ti, Zn, Cu, Pb, Cd, Ba, Hg, S) have shown that the plants absorbed elements and quantities in the different parts like leaves, roots, stems, flowers and fruits. This allows a selective use due to contamination varieties and a possible economic use of parts of the plants and an effective planning of the decontamination conditions

Biodiesel industry waste recovery in agriculture

International audienceWe examine in this study the possibility of using biodiesel industry waste mixed with urban sewage sludge as a source of nutrients for the production and seedling development in agriculture. Biodiesel industry waste is diatomaceous earth (DE) compounds and paraffin. We added DE with urban sewage sludge. The advantage of this operation is to eliminate the two wastes, residues of the biodiesel industry and sludge from wastewater treatment plants. We studied the behavior of Camaldulensis Eucalyptus and white mulberry (Morus Alba Yu vc-62).The Dickson Quality Index (DQI) of White Mulberry and Camaldulensis Eucalyptus plants tested in different substrates (urban sewage sludge and DE) are all above the minimum recommended value of 0.2. The Camaldulensis Eucalyptus and white mulberry (Morus Alba) plants have good growth in substrates containing urban sewage sludge and diatomaceous earth compared to commercial substrate used as control. Biodiesel industry waste can used up to 50% by volume of the substrate without compromising the quality of the plants with a reduction in the cost of production

DEPÓSITOS DE RESÍDUOS DE ROCHAS ORNAMENTAIS: COMPOSIÇÃO, DIMENSIONAMENTO E POSSÍVEIS USOS NO SETOR DE CONSTRUÇÃO CIVIL: Deposits of dimension stone wastes: composition, sizing and use for building

The production of dimension stones in Brazil is relevant mining activity, especially in the State of Espírito Santo, which exports a major part of the Brazilian marbles and granites. Rock blocks processing generates enormous quantity of waste through the discarding of the Dimension Stone Processing Slurry (DSPS), besides block fragments. This work aims to estimate the quantity of DSPS wastes stored in the Municipality of Cachoeiro de Itapemirim (ES), to define its physical and chemical characteristics, and to suggest applications in building, through comparison with bibliographic data. Geoprocessing methods, together with field survey, were used for delimiting and quantifying the volume of the deposits identified in aerial images. The chemical composition of the samples collected in drilling holes was compared with data from previous works that tested the applicability of these wastes to produce red ceramic, concrete, cement and mortar, bricks, and glassy. The chemical composition of the deposited wastes is compatible with the tested materials, indicating the technical viability of their usage as raw material for the building sector. Nevertheless, the segregation of wastes providing from the two main lithological types (marble and granitic rocks), and of conventional and diamond wire looms, will allow better quality control and most noble applications. Keywords: Abrasive Slurry; Use of Waste; Waste Management.A produção de rochas ornamentais no Brasil é uma importante atividade minerária, especialmente no Estado do Espírito Santo, responsável por grande parte da exportação dos mármores e granitos brasileiros. O processo de beneficiamento dos blocos rochosos, gera grande quantidade de resíduos formados pela Lama de Beneficiamento de Rochas Ornamentais (LBRO), além dos fragmentos de blocos. O objetivo desse trabalho é estimar a quantidade de resíduos da LBRO armazenados em depósitos no município de Cachoeiro de Itapemirim (ES), definir suas características físicas e químicas e sugerir aplicações no setor de construção civil. Foram utilizados métodos de geoprocessamento e visitas em campo para delimitar e quantificar o volume dos depósitos identificados em imagens aéreas. A composição química das amostras coletadas em furos de sondagem foi comparada com dados de trabalhos publicados, que estudaram aplicabilidade desses resíduos na produção de cerâmica vermelha, concreto, cimento e argamassa, tijolos e vidrados. A composição físico-química dos resíduos é compatível com a dos materiais já testados, indicando a viabilidade do seu uso como matéria-prima no setor da construção civil. Porém, a separação de resíduos provenientes dos principais grupos litológicos (mármores e granitos), e de teares multifios e convencionais, permitirá maior controle de qualidade e aplicações mais nobres. Palavras-chave: Lama Abrasiva; Uso de Resíduos; Gestão de Resíduos Sólidos

Mineral Dust Environmental Impact in the Region of Pirapora and Varzea da Palma, Minas Gerais: Air, Water, Soil and Plants Pollution

International audienc

Decontamination of middle to low-grade contaminated areas, using a lowcost method

International audienceProtected areas and wetlands often suffer contamination due to outcrops or by passage of contaminated fluids as rain, subsurface water or river infiltration. Due to legislation, in these areas activities which alter the natural environment are not permitted. Here we suggest and describe a methodology that can be used in all low to middle-grade contaminated areas without the necessity of structure changes, intense human interference and/or supervision

P-Li-Be Bearing Pegmatites of the South East Brazil

International audienceThe P-Li-Nb pegmatites are located in the south of Brazil, in the states of Minas Gerais and Espirito Santos. They represent the largest pegmatite fields of Brazil and the richest in precious stones. Two types of pegmatites are characterized by their mineralogical characteristics and tectonic and magmatic relations. The first group occurred during a compressive deformation phase D1 about 582 Ma and 550℃ - 700℃ and 4 - 5 kb. The second pegmatites group was formed during the decompression phase D2 (520 - 500 Ma) of the Brasiliano metamorphic rock fusion. The geochemical parameters of the P-Li-Be bearing pegmatites of the first group show the same trend fractionation, as suggested by the mineralogical composition. The variation of tourmaline and columbite-tantalite composition of the first group game again applies a change of melt composition during the regional development of the pegmatites. A systematic compositional trend seems to suggest a petrogenetic link between the pegmatites of the region. The Fe/Mn ratio of tourmaline in samples of the first group shows the same behavior as in columbite-tantalite and garnets. The simple pegmatites are transiting north in the gem-rich pegmatites. The Fe/Mn ratio not only shows qualitatively the fractionation index, the degree of regional development, but also the internal development of the body. The ratio shows a negative correlation with lithium. The Co, Zn and Nb contents are rising at first group, but falling when starting crystallization of garnet, columbite-tantalite, and Behierit

Site partitioning of Cr 3+ in the trichroic alexandrite BeAl 2 O 4 :Cr 3+ crystal: contribution from x-ray absorption spectroscopy

International audienc