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南非年产黄金670余吨,约占世界总产量的50％。通常,含金砾岩矿体呈板状赋存在较稳固的石英岩中,厚度1—2m,倾角15—30°,平均20°.矿石平均含金6.5g/t.最高14.4 g/t。金铀矿石平均含铀0.13％。采矿方法主要是壁式空场采矿法,采空区用立柱、木垛支护,坑木消耗多,劳动生产率低,全员效率仅206t/人年。现今,平均开采深度为2000m,最深的3582m。随着开采工作继续向深部发展,地压应力显著增加,冒顶、岩爆时有发生,矿石损失贫化相应加大,作业很不安全。为了改进这一状况,七十年代中期以来,不少矿山
South Africa produces more than 670 tons of gold a year, accounting for about 50% of the world’s total output. Generally, the ore-bearing conglomerate contains plate-shaped deposits of relatively stable quartzite with a thickness of 1-2 m and an inclination of 15-30 ° with an average of 20 °, with an average ore content of 6.5 g / t and a maximum of 14.4 g / t. Uranium ore contains uranium 0.13% on average. Mining methods are mainly wall empty field mining law, goaf column, wood stack support, pit consumption, labor productivity is low, full efficiency of only 206t / person-year. Today, the average depth of exploitation of 2000m, the deepest 3582m. As mining continues to develop in depth, the compressive stress increases significantly, and the roof falls and rockbursts occur from time to time. As a result, ore loss and depletion are correspondingly increased, and operations are unsafe. In order to improve this situation, many mines have been operating since the mid-1970s