Oxigênio-18 e deutério traçadores do sistema de aqüíferos na Bacia Sedimentar do Araripe

• Ano de defesa: 2012
• Autor(a) principal: Brito, Adriano Leal de
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Palavras-chave em Português: Isótopos ambientais; Hidrologia isotópica; Environmental isotopes; Isotope hydrology
• Link de acesso: http://www.repositorio.ufc.br/handle/riufc/13703

The natural tracers deuterium and oxygen-18 were used to identify the dynamic characteristics of the groundwater reserves in the Araripe Sedimentary Basin, through the analysis of water samples collected in 40 wells in January, April, July and October 2011. The sampling points are located in 08 municipalities and electrical conductivity measurements, which expresses water salinity, were also performed. The results show spatial and temporal variation of the parameters analyzed, but the average values of δ18O in samples from 33 wells is -3.22 ± 0.05 (‰) which is the average rainfall in the region today. Samples of the remaining seven wells showed higher fluctuations and four had values below -3.2 ‰. The meteoric lines that express measures of deuterium versus oxygen-18, constructed with values of each sample show a mean slope of 7.87 ± 0.60 ‰ about the value of the World Meteoric Line. The excess of deuterium in the sample period increased from 7.26 to 9.38 ‰ reflecting internal processes in the aquifer. Samples with values of δ18O in meteoric waters below the current mix of show paleowater already identified with modern recharge water, the samples with these values are not distinguishable by their electrical conductivities that are current in the range of samples characterizing the importance of isotopic tracers