As one of the geological prospecting method for civil engineering, electrical prospecting method is used to obtain an information of geological profile for geological structure, basement profile of construction, landslide profile and so on. However, recently, the authors need to develop a new technique which provides a moving profile of resistivity due to the groundwater flow for making clear the mechanism of the nature of groundwater contamination.
Utilization of electrical prospecting method for detecting the variation of resistivity for short term range needs the improvement of measuring efficiency and high accuracy. At the point the authors described in the former paper.
In this paper, visualization of the movement of an electrolyte tracer in an analogic sand layer equipment is demonstrated by permeability experiment and by means of repeated resistivity measurement of which electrical pole arrangement is dipole-dipole. Sodium chloride solution of which salinity is 1.0 percent for replacement ex-periment or 3.0 percent for injection experiment, respectively, is percolated as an electrolyte tracer into a sand layer in steady state.
The effectiveness of this method is ensured with the result of electrical conductivity measurement and measured flow velocity of this method agree well with one calculated from hydraulic gradient.
Then this method is proved by the experimental approach. This method provides wide applicability such as detecting of ground water path in landslide or dam basement and analysing of flow direction and velocity of groundwater contaminants which are electrolytic.
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