Laboratory modelling of the response of fixed loop EM systems over multiple targets in conductive environments using the parallel line mode of operation

Abstract

The large magnetic moments of fixed loop transmitters and the low geometric attenuation of their transmitted signal provide for potential depths of exploration in excess of 500 metres. This has led in the past decade to the development of several new devices of this type. However, this performance can only be achieved if the target conductor lies midway along the available traverse length which seldom exceeds 2000 metres. Any deviation from this geometry means that the anomaly due to a deep target is truncated by the ends of the available traverse. The requirement that the target be located at mid traverse can never be met in an exploration survey unless the location of the target is known ahead of the placing of the transmitter.