Evaluation of spectral induced polarization field measurements in time and frequency domain

Spectral induced polarization (SIP) measurements have been demonstrated to correlate with important parame-
ters in hydrogeological and environmental investigations. Although SIP measurements were often collected in the
frequency domain (FDIP), recent developments have demonstrated the capabilities to solve for the frequency-de-
pendence of the complex conductivity through measurements collected in the time domain (TDIP). Therefore,
the aim of our field investigations is a comparison of the measured frequency-dependence at a broad frequency
range resolved through FDIP and TDIP. In contrast to previous studies, we conducted measurements with dif-
ferent instruments and measuring technologies for both FDIP and TDIP. This allows for investigating the robust-
ness of different measurements and assessing various sources of errors, for the assessment of the advantages and
drawbacks from different measuring techniques. Our results demonstrate that data collected through different
instruments are consistent. Apparent resistivity measurements as well as the inversion results revealed quantita-
tively the same values for all instruments. The measurements of the IP effect are also comparable, particularly
FDIP readings in the low frequencies (< 10 Hz) revealed to be quantitatively the same for different instruments.
TDIP measurements are consistent for data collected with both devices. As expected, the spatial distribution of
the values is also consistent for low frequency data (in FDIP) and late times measurements in TDIP (> 0.1 s).
However, data quality for higher frequencies in FDIP (i.e., early times in TDIP) show larger variations, which
reflects the differences between the instruments to deal with the electromagnetic contamination of the IP data.
Concluded in general, the different instruments and measuring techniques can provide consistent responses for
varying signal-to-noise ratio and measuring configurations.