A new dual frequency moving source-receiverem unit

Summary

The paper describes a new portable highly sensitive dual-frequency electromagnetic prospecting unit designed for detailedem surveys based on moving source compensation method. Employing horizontal-horizontal coil profiling, the unit is capable of working on a source-receiver separation of 330 feet (ninety meters) on both frequencies of 500 cycles per sec and 1500 cycles per sec to an accuracy of ±1%. The presence of secondary field characterised by two related components ‘in-phase’ and ‘out-of-phase’ are measured accurately to define the conductor characteristics. An unique provision is made for compensating the phase-shifts in the presence of medium to poor conductors, such as conductive overburden or relatively disseminated ore mineralisation.