Spectral induced polarization (SIP), or complex resistivity (CR) and also complex conductivity (CC), is a
geophysical survey technique and an extension of the
induced polarization (IP) method, being itself an extension of measuring the Earth's resistance at a single frequency or under
direct current (DC) (a technique commonly known by the name
resistivity).
SIP measures the frequency-dependent (i.e.
spectral) complex
impedance, equivalent to the amount of
resistance
Resistance may refer to:
Arts, entertainment, and media Comics
* Either of two similarly named but otherwise unrelated comic book series, both published by Wildstorm:
** ''Resistance'' (comics), based on the video game of the same title
** ''T ...
and
phase shift between electric
current and
voltage. The usual frequency range for
alternating current (AC) applied during SIP surveys is tens of
kHz
The hertz (symbol: Hz) is the unit of frequency in the International System of Units (SI), equivalent to one event (or cycle) per second. The hertz is an SI derived unit whose expression in terms of SI base units is sā1, meaning that on ...
to
MHz. As with other geophysical methods, SIP aims to distinguish material properties of the subsurface, such as
salinity
Salinity () is the saltiness or amount of salt dissolved in a body of water, called saline water (see also soil salinity). It is usually measured in g/L or g/kg (grams of salt per liter/kilogram of water; the latter is dimensionless and equal ...
and
saturation.
See also
*
AC impedance spectroscopy
Dielectric spectroscopy (which falls in a subcategory of impedance spectroscopy) measures the dielectric properties of a medium as a function of frequency.Kremer F., Schonhals A., Luck W. Broadband Dielectric Spectroscopy. ā Springer-Verlag, 200 ...
*
Electrical resistivity measurement of concrete
References
Geophysical imaging
{{Geophysics-stub