Electrical and Electromagnetic Prospecting

1. INDUCED POLARISATION
METHOD
 TIME-DOMAIN MEASUREMENTS
 FREQUENCY-DOMAIN MEASUREMENTS
 APPLICATIONS OF IP METHOD

2. Time-Domain Measurements
 In the time-domain induced polarization method, the voltage response is observed
as a function of time after the injected current is switched off or on.
 Time-domain IP methods measure considers the resulting voltage following a
change in the injected current.
 The time domain IP potential response can be evaluated by considering the mean
value on the resulting voltage, known as integral chargeability and considering the
shape of the potential response.

3. Frequency-Domain Measurements
 In the frequency-domain induced polarization mode, an alternating current is injected
into the ground with variable frequencies.
 Voltage phase-shifts are measured to evaluate the impedance spectrum at different
injection frequencies, which is commonly referred to as spectral IP.
 Frequency-domain IP methods uses alternating currents (AC) to induce electric
charges in the subsurface, and the apparent resistivity is measured at different AC
frequencies.

4. Applications of IP Methods
 Mineral exploration
 Mining industry
 Hydro geophysical surveys
 Environmental investigations
 Geotechnical engineering projects
 Groundwater exploration
 Detection of metal pipes and cables
 Mapping soil and groundwater contamination.

5. THA
NK