Spectral induced polarization

Patent Pending Spectral induced polarization (SIP) or Complex resistivity 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 (a technique commonly known by the name resistivity).[1] SIP measures the frequency-dependent (i.e. spectral) complex impedance, equivalent to the amount of resistance and phase shift between electrical current and voltage.