INDUCED POLARIZATION

Induced polarization (IP) is a geophysical survey method that measures the ability of subsurface materials to store and release electrical charge when an externally applied current is switched off. When surveyors inject current into the ground through electrodes and then cut the current, certain minerals and porous materials continue to discharge stored electrical energy for a measurable period. This delayed voltage decay, called the IP effect, provides information about subsurface composition that standard resistivity measurements alone cannot reveal.

IP surveys use two primary measurement approaches. Time-domain IP measures the voltage decay curve after current cutoff, recording chargeability values in milliseconds at defined time intervals after switch-off. Frequency-domain IP applies alternating currents at multiple frequencies and measures the phase shift and amplitude variation in the received voltage signal. Both methods detect the same physical phenomenon but suit different field conditions and data interpretation workflows.

Chargeability contrast between rock and mineral types drives IP’s effectiveness as an exploration tool. Disseminated sulfide minerals including pyrite, chalcopyrite, and galena produce strong IP responses due to electrode polarization at mineral grain surfaces. Clay-rich sediments generate IP effects through membrane polarization in their pore structure. This distinction helps exploration teams separate economic mineralization targets from clay-hosted false anomalies during data interpretation.

In Pakistan, induced polarization surveys support mineral exploration programs targeting copper, gold, and base metal deposits in Balochistan and KPK, groundwater aquifer characterization in arid regions, environmental contamination mapping around industrial sites, and archaeological subsurface investigation where IP contrasts reveal buried structural or organic features.

Tactical Supply Pakistan supplies induced polarization survey equipment for mineral exploration, groundwater investigation, and environmental geophysical survey applications across Pakistan.