@article{fdi:010091420,
  title = {{W}ater mixing processes in a complex multi-layer hydrosystem in southwestern {M}adagascar : a combined isotopic and piezometry approach},
  author = {{C}arri{\`e}re, {S}.{D}. and {R}akotomandrindra, {P}.{F}.{M}. and {H}eath, {T}. and {C}halikakis, {K}. and {G}illon, {M}. and {L}eblanc, {M}. and {T}weed, {S}arah},
  editor = {},
  language = {{ENG}},
  abstract = {{W}ater transfers through a multilayered aquifer system are difficult to characterize. {T}his study explores whether the conceptual model of water mixing at depth can be extrapolated over a hydrosystem extended across several tens of kilometers and including multiple aquifer layers. {T}he processes are investigated using a combination of isotope tracers and piezometric monitoring over 10 years. {T}he goal of this approach is to better understand how water transfer occurs throughout a complex and poorly documented hydrosystem of the {M}ahafaly {P}lateau in southwestern {M}adagascar. {T}he results show a clear smoothing of isotopic variability with depth, associated with a smoothing of the recharge peaks. {I}sotopic values are strongly variable in the near surface (from -6.8 to -2.5% {O}-18) and stabilize at a critical depth (near 20 m) at around -4.7% {O}-18. {T}hese results indicate high vertical flows through the aquifer system, where there is neither obvious dominant recharge via preferential pathways nor lateral mixing. {S}uch a strong smoothing effect on groundwater isotopic variability with depth has been rarely observed so clearly over a large spatial scale. {T}hese results provide information on a remote groundwater flow system at a scale pertinent to groundwater resource assessment. {T}he results also indicate that the {N}eogene aquifers of the {M}ahafaly {P}lateau are poorly connected with other water resources (rivers, old sedimentary formations) except for the percolation of water towards the deep {E}ocene karst. {T}his means that groundwater resources in the {A}nkazomanga {B}asin are limited and that it is essential to understand and quantify recharge for sustainable groundwater management.},
  keywords = {{MADAGASCAR} ; {MAHAFALY} {PLATEAU}},
  booktitle = {},
  journal = {{H}ydrogeology {J}ournal},
  volume = {31},
  numero = {8},
  pages = {2337--2346},
  ISSN = {1431-2174},
  year = {2023},
  DOI = {10.1007/s10040-023-02731-5},
  URL = {https://www.documentation.ird.fr/hor/fdi:010091420},
}