A glimpse of the Anthropocene captured by environmental tracers in the groundwater of a fractured aquifer
Résumé
Goldschmidt 2021 Abstract
https://doi.org/10.7185/gold2021.6897
A glimpse of the Anthropocene
captured by environmental tracers in
the groundwater of a fractured
aquifer
DR. ELIOT CHATTON1, THIERRY LABASQUE2,
WERNER AESCHBACH3, VIRGINIE VERGNAUD2 AND
LUC AQUILINA4
1CNRS UMR61182Univ. Rennes, CNRS, UMS 33433Institute of Environmental Physics4Université de Rennes 1 Géosciences Rennes UMR 6118
Presenting Author: eliot.chatton@univ-rennes1.fr
The Anthropocene is an epoch in Earth’s history that has been
proposed to characterise the global impact of human activities on
the Earth's atmosphere, biosphere, hydrosphere, geosphere, i.e.
the Critical Zone.
Just as for past climates, the signature of these anthropogenic
impacts are recorded by environmental tracers dissolved in
groundwater that could provide a better understanding of
groundwater flows, residence time and mixing thus providing
information on this major water resource both in terms of
quantity and quality.
In this study, we use dissolved gases (CFCs, SF6, 4He, 14C,
noble gases, VOCs, stable isotopes) and groundwater chemical
composition as environmental tracers to unveil insights of the
Anthropocene in a fractured aquifer in the northwest of France.
We analyse the impact of groundwater abstraction on residence
time and excess air composition. We evidence the influence of
climate change on groundwater recharge temperature (noble gas
temperatures, NGT). We also quantify the appearance of
anthropogenic compounds over the last decades.
These observations enable us to define the Anthropocene
signature in groundwater and the distribution of its impacts on
the groundwater resource in order to gain a better picture of its
resilience in the future.