Geophysical Response Over A Kimberlite

Following a combined airborne frequency domain EM and aeromagnetic survey, a<br>prominent circular anomaly was observed and interpreted as a possible kimberlite<br>pipe. On drill investigation this interpretation proved correct. A ground<br>geophysical program consisting of magnetics, gravity, frequency and time<br>domain EM, radiometrics and physical property measurements was embarked<br>upon. All the above techniques gave an unambiguous response from the<br>kimberlite pipe except for the radiometric technique.