A multiple transmitter/receiver system: the advantage of summing responses from multiple transmitters

Abstract

Summary Many ground electromagnetic (EM) systems have been deployed in the Sudbury basin and under ideal conditions these systems are capable of detecting large conductors to depths of approximately 800m; however, more common detection limits are in the order of a couple of hundred meters (<400m). Although these systems have had great success in Sudbury, they may experience two weaknesses for deeper conductors: poor coupling and small signal-tonoise ratios, decreasing the quality and interpretability of the data. A time-domain electromagnetic survey was conducted over a known conductor to test a new methodology, which could potentially see deeper targets. The coupling weakness was addressed through multiple transmitter locations and the signal-to-noise ratio was increased above the noise threshold by spatial stacking of receiver measurements (from the various transmitterreceiver combinations).