Boron Isotope Characterization to Design a Frame of Hydrogeological Functioning of a Wetland System (Massif Central, France)

Philippe Négrel (1) , Catherine Guerrot (1) , Romain Millot (1) , Emmanuelle Petelet-Giraud (1)

1 BRGM - Bureau de Recherches Géologiques et Minières (BRGM)

Multi-isotopic approaches (Li, Sr, O, H), combined with hydrological tools, have been already applied for tracing the water and dissolved-element fluxes in a peatland in Central France. Here, we applied B isotopes. The 11 B ratios increase from river draining basalts (~ 0‰) up to springs bordering the peatland (> +25‰). Peatland groundwaters have intermediate 11 B: 7.8 to 19.4‰. This range is accompanied by an increase in the Ca contents between the river draining basalts and water in the peatland. In a 11 B vs. Ca/B diagram, the role of water rock interaction and present day fertilizer inputs is evidenced, as for Sr isotopes.

Keywords: peat land; groundwater; B isotopes; Massif Central

Domains: Earth Sciences

Philippe Négrel, Catherine Guerrot, Romain Millot, Emmanuelle Petelet-Giraud. Boron Isotope Characterization to Design a Frame of Hydrogeological Functioning of a Wetland System (Massif Central, France). Procedia Earth and Planetary Science, 2015, 13, pp.11 - 15. ⟨10.1016/j.proeps.2015.07.003⟩. ⟨hal-03699691⟩