Abstract The object of this study can be found among the various ornamental rocks used in historic buildings in the city of Rio de Janeiro. It is a degraded Leptinito Gneiss that makes up one of the support columns of the kitchen of the Mosteiro de São Bento (Monastery of Saint Benedict) in Rio de Janeiro. The main aim of the present study is to identify the causes of the high degree of degradation of said column. Non-destructive tests were performed, and laboratory evaluation of the disintegrated fragments may help restore and conserve this column in the future. Results obtained from the tests performed on the altered column were compared to those obtained from another column in the monastery, also built in Leptinito, which is more intact and is a sound Leptinito Gneiss. The results showed that degradation of the column is caused by the crystallization of salts (halite) inside the rock, which is reducing its mechanical strength and causing an imminent risk of collapse.

ABSTRACT When considering the numerous events that have prohibited the development of scientific projects or caused destruction of outcrops, it is clear that there is rapidly increasing necessity to define a Brazilian Code of Conduct for geological fieldwork. In general, this destruction is attributed to lack of knowledge as to the relevance of geological sites. The aim of this Code of Conduct is to guide geologists to adopt good practices during geoscience activities. Proposed guidelines are based on Codes of Conduct from other countries, mainly Scotland and England, on situations described in papers and on the personal experience of the authors. In this paper 29 points are suggested, in order to guarantee that fieldwork is conducted in accordance with geoethics, geoconservation and sustainability values. The proposal is structured in three parts: (1) Behavior and practices in respect to local traditions and providing information to the population; (2) Measures to minimize degradation on outcrops; and (3) Safety. The proposal seeks to broaden the debate on the need for responsible behavior during fieldwork, in order to promote respect for geodiversity. Through this code, Brazilian geoscientists will be able to contribute to the conservation of geological heritage and of outcrops with special educational relevance.

O objetivo do trabalho foi avaliar a qualidade das águas da Bacia Hidrográfica do Rio São Domingos (BHRSD), correlacionando-a com as possíveis fontes poluidoras advindas das características naturais e antrópicas da área. Alguns parâmetros físico-químicos foram analisados em 65 pontos (superficiais e subterrâneos) de amostragem. Os resultados foram confrontados com os limites estabelecidos pelas Resoluções CONAMA 357/05 (classe 2), que trata das águas superficiais, e CONAMA 396/08 (consumo humano), que contempla as águas subterrâneas. Foram analisados diversos cátions e ânions, temperatura, alcalinidade, pH, condutividade elétrica (CE), sólidos totais dissolvidos (STD), oxigênio dissolvido (OD), demanda bioquímica de oxigênio (DBO), coliformes termotolerantes e alguns agrotóxicos organoclorados e organofosforados. Os parâmetros que apresentaram inconformidades, com maior frequência, foram: alumínio dissolvido, boro total, ferro dissolvido, manganês total, nitratos, pH, OD, DBO e alguns organoclorados e organofosforados. Embora a área esteja situada em terreno cristalino tropical úmido, o que pode justificar os teores elevados de alumínio, manganês e ferro, os resultados apontam que o comprometimento da qualidade das águas da BHRSD é influenciado pela prática agrícola.

The purpose of this article is the evaluation of São Domingos River Basin (SDRB) water quality and tentative correlations with natural and anthropic polluting sources. In order to achieve it, physicochemical parameters were analyzed in 65 surface and groundwater sampling points, in accordance to standards established by the Brazilian Environmental Authority, CONAMA 357/05, Class 2, for surface water and CONAMA 396/08, Class human, consumption for groundwater. The analyzed parameters include major cations and anions, temperature, pH, electric conductivity, total dissolved solids (TDS), alkalinity, dissolved oxygen (DO), biochemical oxygen demand (BOD), thermotolerant coliforms, organochlorides and organophosphorus compounds. Parameters with concentrations more frequently in unconformity with regulations are: aluminum, boron, iron, manganese, nitrates, DO, BOD and some organochlorides and organophosphorus compounds. Results show that distribution of contamination is strongly influenced by the human presence, such as rural and urban population and tomato culture. Natural aspects also play a major role, since availability of aluminum, iron, and manganese in near-surface waters in tropical environment depends on input from processes taking place in leaf litter and topsoil.