Ann: High-Grade Copper-Gold Discovery At Cloncurry, page-29

A DHEM on the two holes will be very interesting. As indicated, as strong conductor can mask underlying conductors and as well there is a depth limit to which airborne or even surface EM studies are capable of detecting. So its possible we could be sitting on something of considerably larger size than depicted in their initial conductor sketch.
In fact I recall from SIR EM work that they missed the adjacent ( extended) Ni conductors for the reasons above, and only when they did DHEM work did they identify the extensions of their deposit