1975 Volume 25 Issue 130 Pages 143-154
The Dowa Mining Co., Ltd. carried out an exploration program at Matachewan area, East Canada using Helicopterborne Electromagnetic system for the first stage of the program in 1971.
The aim of this program was to find out massive sulfide orebodies in Canadian Shield with thin surface cover of glacial deposits.
We used DIGHEM system for this work which has three receiving coils with perpendicular orientations to each other. We believe that this system is superior to other systems in the discrimination and the resolution between conductors.
As the results of DIGHEM survey in this program, we picked up twenty target areas from the record for the next stage program. After the cover of ground follow-up survey for each of those target areas, sixteen angle diamond drill holes (average length 100m) were completed in the eleven target areas.
All of those drill holes intersected more or less amount of uneconomic pyrite, pyrrhotite or magnetite mineralization just below the zone of conductive bedrock detected by DIGHEM and ground EM survey.
We have not discovered the economical ore deposit, but this result makes our confidence stronger about the prospecting approach mainly based on geophysical methods.
