@article{fdi:010070292,
  title = {{T}ime-lapse electrical surveys to locate infiltration zones in weathered hard rock tropical areas},
  author = {{W}ubda, {M}. and {D}escloitres, {M}arc and {Y}alo, {N}. and {R}ibolzi, {O}livier and {V}ouillamoz, {J}ean-{M}ichel and {B}oukari, {M}. and {H}ector, {B}. and {S}{\'e}guis, {L}uc},
  editor = {},
  language = {{ENG}},
  abstract = {{I}n {W}est {A}frica, infiltration and groundwater recharge processes in hard rock areas are depending on climatic, surface and subsurface conditions, and are poorly documented. {P}art of the reason is that identification, location and monitoring of these processes is still a challenge. {H}ere, we explore the potential for time-lapse electrical surveys to bring additional information on these processes for two different climate situations: a semi-arid {S}ahelian site (north of {B}urkina and a humid {S}udanian site (north of {B}enin), respectively focusing on indirect (localized) and direct (diffuse) recharge processes. {T}he methodology is based on surveys in dry season and rainy season on typical pond or gully using {E}lectrical {R}esistivity {T}omography ({ERT}) and frequency electromagnetic ({FEM}) apparent conductivity mapping. {T}he results show that in the {S}ahelian zone an indirect recharge occurs as expected, but infiltration doesn't takes place at the center of the pond to the aquifer, but occurs laterally in the banks. {I}n {S}udanian zone, the {ERT} survey shows a direct recharge process as expected, but also a complicated behavior of groundwater dilution, as well as the role of hardpans for fast infiltration. {T}hese processes are ascertained by groundwater monitoring in adjacent observing wells. {A}t last, {FEM} time lapse mapping is found to be difficult to quantitatively interpreted due to the non-uniqueness of the model, clearly evidenced comparing {FEM} result to auger holes monitoring. {F}inally, we found that time-lapse {ERT} can be an efficient way to track infiltration processes across ponds and gullies in both climatic conditions, the {S}ahelian setting providing results easier to interpret, due to significant resistivity contrasts between dry and rain seasons. {B}oth methods can be used for efficient implementation of punctual sensors for complementary studies. {H}owever, {FEM} time-lapse mapping remains difficult to practice without external information that renders this method less attractive for quantitative interpretation purposes.},
  keywords = {{R}esistivity ; {T}ime-lapse ; {I}nfiltration ; {H}ard rock ; {B}urkina {F}aso ; {B}enin ; {BURKINA} {FASO} ; {BENIN} ; {ZONE} {SAHELIENNE} ; {ZONE} {SOUDANIENNE}},
  booktitle = {},
  journal = {{J}ournal of {A}pplied {G}eophysics},
  volume = {142},
  numero = {},
  pages = {23--37},
  ISSN = {0926-9851},
  year = {2017},
  DOI = {10.1016/jjappgeo.2017.01.027},
  URL = {https://www.documentation.ird.fr/hor/fdi:010070292},
}