Groundwater Flow Monitoring via Joint Time-lapse Electrical Resistivity
and Self Potential Data Tomography
Abstract
Revealing the dynamics of groundwater movement in the vadose zone is
crucial to groundwater management and artificial recharge. In this
study, the groundwater flow characterization of the pumping process is
monitored by the joint time-lapse electrical resistivity tomography
(ERT) and self-potential (SP) data tomography. The ERT data invert the
resistivity distribution, which relates to the variation of soil
moisture content during the pumping process. Base on the groundwater
motion feature, the SP data provide a direct way to invert the current
density and estimate the permeability. A total of 24 hours of time-lapse
surveys show a significant increase and decrease in resistivity and
permeability during water pumping and groundwater recharge, which
suggests groundwater decline and recovery process. These results have an
excellent agreement with the groundwater level monitoring result.
Combining ERT and SP data can provide a reliable way in groundwater or
other hydrogeological surveys.