HR: 0800h
AN: H21A-0173    [Abstracts]
TI: Quantitative evaluation of perched groundwater storage using electric resistivity method in mountainous headwater catchments at Shiranui, Kumamoto, Japan
AU: * Yamamiya, K
EM: k.yama@es.sci.kumamoto-u.ac.jp
AU: Shimada, J
EM: jshimada@sci.kumamoto-u.ac.jp
AU: Ono, M
EM: masa.ono@es.sci.kumamoto-u.ac.jp
AU: Sueda, T
EM: t.sueda@es.sci.kumamoto-u.ac.jp
AB: The selected headwater catchments for this study have been done many hydrometric observations to understand the rainfall-runoff process during last five years and the distinctive seasonal perched groundwater aquifer system has existed only in the wet season to support the local natural spring discharge. According to the previous study using electric resistivity method along one survey line in the study catchments (Ono, 2006), the perched groundwater system exists in the strongly weathered auto-brecciated Andesite lava and a continuous aquifer belt is developed seasonally to support the local spring discharge. In this study, the same electric resistivity technique was applied along the selected representative three survey lines to understand the three dimensional structure of this perched aquifer system. Also the seasonal resistivity difference between the resistivity distributions along the particular survey line was calculated to evaluate the groundwater storage of the perched aquifer. The evaluated groundwater storage capacity along three survey lines were used to synthesize the catchments scale three dimensional aquifer storage volume of the studied perched aquifer. The estimated storage volume of the perched aquifer was compared with the observed cumulative spring discharge rate during the wet season to evaluate the method. Although there are many uncertainties for this estimation, the estimated three dimensional storage volume of the perched aquifer by the electric resistivity method and the observed spring discharge during the wet season show relatively close value each other. This result strongly supports that the estimated three dimensional structure of the perched aquifer system by electric resistivity method seems to be reasonable for the studied head water catchments.
DE: 1829 Groundwater hydrology
DE: 1835 Hydrogeophysics
DE: 1843 Land/atmosphere interactions (1218, 1631, 3322)
DE: 1847 Modeling
DE: 1879 Watershed
SC: Hydrology [H]
MN: 2007 Fall Meeting