Underground on the Witwatersrand, in South Africa. On the day following the Johannesburg seminar, the group drove to the Carltonville area and were given an underground tour of the East Driefontein mine in the morning, followed in the afternoon by the inspection of core through the Witwatersrand Basin and the main reefs, hosted by expert, experienced, geologists from Gold Fields. In the late afternoon and evening they drove the ~230 km to Welkom. On the next morning, the group had another highly informative underground visit to Avmin's Lorraine mine and the connected Target Project, 6 km to the north, followed by core inspection of the main reefs. We were then taken into the field to inspect the deep 3-D seismic program being utilised to guide the drilling of the Target Project gold deposit. The Target deposit comprises some 67 individual mineralised conglomerates, sufficiently close spaced to be bulk mined, as indicated by the discovery drill intersection of 128.6 m @ 6.42 g/t Au. This contrasts to the individual narrow reef mining utilised in the bulk of the Witwatersrand Basin mines.
Top left members of the group with Gold Fields geologists on the 34 level, 2405 m below surface, in the East Driefontein mine at Carltonville; Top centre: With Avmin Chief Geologist Dries Ferreira (centre), who gave the group the benefit of his experience, underground at Lorraine discussing the geology of the deposit and the Witwatersrand Basin; Top right: a headframe at East Driefontein; Bottom left Rod Tucker, Chief Geologist Exploration (right) and Neil Gray, manager Geological Services (left) at Avmin, underground with the tour group, providing an exploration perspective; Bottom centre: rehydrating underground at East Driefontein; Bottom right coming out of the cage at Lorraine. Photographs by Mike Porter
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![[Underground on the Witwatersrand]](agphoto7.jpg)