The new electromagnetic technology for exploration of complex ores and gold

Induced polarization (IP) surveys have been utilized in the practice of mineral exploration for base metals and gold since the 1960s and have led to a number of important discoveries. However, the classical technology of IP measurements has never been truly efficient because of noise from electromagnetic relaxation (transient process). We have designed a new technology, including acquisition instruments and processing software, to measure responses of a polarizing earth with a differential current line which virtually cancels the relaxation component. Once the relaxation component has been cancelled, there remain only the “pure” IP signals to measures, which become very high, and the exploration work thus becomes tens of times more productive. The basic idea of the new sounding method consists in the use of two transmitters (grounded lines) oriented in opposite directions. In terms of physics, the idea is to cancel (subtract) the relaxation component (transient process) of the electromagnetic field and to add the polarization component using pulses of different directions. The new technology is a workable exploration tool for complex ores and gold associated with sulfide mineralization in quartz.