CALCULATION OF SALT TRACER CONCENTRATIONS FROM SELF -POTENTIAL DATA

Abstract

Applying the self-potential method to detect the transport of salt tracer through the dam's preferential flow paths may be a possible solution that allows determining the direction and velocity distribution of seepage flow. To demonstrate the relationship between the potential signals and the salt concentrations, the report proposes a method to invert the measured self-potential signals into salt tracer concentration curves based on the solution of the total current density equation. The method was then verified on experimental data published by Maineult and Bernabé (2005). The calculation results show that the concentration values of the salt tracer converted from the experimental self-potential signals agree with the calculated values from the advection-dispersion equation. In addition, the study shows that the time of maximum variation of the potential signal is consistent with the time of tracer appearance at the measurement point.