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Chemical and carbon isotopic composition of dissolved organic carbon in a regional confined methanogenic aquifer

R. Aravena·L.I. Wassenaar·E.C. Spiker
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Abstract

This study demonstrates the advantage of a combined use of chemical and isotopic tools to understand the dissolved organic carbon (DOC) cycle in a regional confined methanogenic aquifer. DOC concentration and carbon isotopic data demonstrate that the soil zone is a primary carbon source of groundwater DOC in areas close to recharge zones. An in-situ DOC source linked to organic rich sediments present in the aquifer matrix is controlling the DOC pool in the central part of the groundwater flow system. DOC fractions, 13C-NMR on fulvic acids and 14C data on DOC and CH4 support the hypothesis that the in-situ DOC source is a terrestrial organic matter and discard the Ordovician bedrock as a source of DOC. ?? 2004 Taylor and Francis Ltd.

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R. Aravena, L.I. Wassenaar, E.C. Spiker. 2004. Chemical and carbon isotopic composition of dissolved organic carbon in a regional confined methanogenic aquifer. https://doi.org/10.1080/10256010410001671050

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