Integrated Helicopter ZTEM-gravity-magnetic System Results over the Vredefort Dome Structure, South Africa

In January-February 2016 an integrated multi-parameter helicopter-borne geophysical system was flown over the Vredefort Dome Structure in South Africa. The system consisted of an on-board GT-2A gravimeter and a towed-bird ZTEM(Z-Axis Tipper Electromagnetics)with caesium magnetometer. The survey consisted of nine (9) approximately 70km long NW-SE oriented flight lines, totaling 640km, acquired at a nominal spacing of 1000m over an area of approximately 650 square kilometers. The survey data are presented and analyzed with the support of 2D and 3D inversion. The results appear to correlate well with previous geophysical survey data and the known geology. These results demonstrate that high quality gravity measurements can be made concurrently with helicopter ZTEM and magnetics, and therefore represents a potentially useful multi-parameter and deep penetrating geophysical mapping tool.