@article{fdi:010057127,
  title = {{T}owards a better estimate of storage properties of aquifer with magnetic resonance sounding},
  author = {{V}ouillamoz, {J}ean-{M}ichel and {S}okheng, {S}. and {B}ruy{\`e}re, {O}. and {C}aron, {D}elphine and {A}rnout, {L}.},
  editor = {},
  language = {{ENG}},
  abstract = {{P}roviding people with fresh water is one of the greatest challenges of the century. {S}ince most of the world's liquid fresh water is groundwater, the knowledge of aquifer storage properties is essential. {M}oreover, there is a need to focus research on poor aquifers (i.e. capable of providing about 100 m(3)/day) which will play an increasing role for supplying many human communities. {T}his paper concerns a study carried out in a clayey sandstones aquifer in {N}orthern {C}ambodia. {C}onventional hydraulic methods used to characterize aquifers are costly, time-consuming and thus they are usually not used in most of the water projects in developing countries. {T}herefore, geophysical methods can be useful if they improve aquifer characterization. {A}s compared to other non-invasive geophysical methods, magnetic resonance sounding ({MRS}) is selective to groundwater. {MRS} results are the distribution of both water content and pore-size related-parameters as a function of depth. {H}owever, relationships between the field scale {MRS} results and hydrogeological storage-related properties have not been well established yet. {W}e present in this paper a comparison of {MRS} results with both specific yield calculated from pumping tests and effective porosity calculated from tracer tests. {W}e found that the {MRS} water content is equal or higher than the specific yield and the effective porosity, thus indicating that {MRS} also measures capillary water in unsaturated zone and part of the bound groundwater attached to the aquifer solid matrix. {W}e also found that the {MRS} pore-size parameter is linearly correlated with both the effective porosity and the specific yield, thus suggesting that the hydrogeological storage properties are mainly controlled by the size of the pores of the aquifer. {C}onsequently, we adapted an approach used in the oil industry for differencing gravitational water from capillary water and from bound water, based on the {MRS} pore-size parameter. {I}n the clayey sandstones of {C}ambodia, our approach named {MRS} apparent cutoff time approach, allowed calculating specific yield with an average error of 23% (which is far less than the previous published results), and for the first time it allowed calculating effective porosity (with an average error of 11%). {W}e conclude that the {MRS} apparent cutoff time approach is useful for estimating aquifer storage properties down to 50-80 m deep, in a single day and at an affordable cost.},
  keywords = {{H}ydrogeophysics ; {M}agnetic resonance sounding ; {S}pecific yield ; {E}ffective porosity ; {U}nconfined aquifer},
  booktitle = {},
  journal = {{J}ournal of {H}ydrology},
  volume = {458},
  numero = {},
  pages = {51--58},
  ISSN = {0022-1694},
  year = {2012},
  DOI = {10.1016/j.jhydrol.2012.06.044},
  URL = {https://www.documentation.ird.fr/hor/fdi:010057127},
}