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最近几年,随着金价上涨,世界黄金产量年年上升。但南非黄金产量从1970年达到1000吨最高记录后,年年下降,1987年降到607吨,预计1988年将降到600吨。其主要原因是: 开采深度增加。南非大约有40多个地下金矿,近20年来开采深度增加了1000m。产量之和占60％的一些金矿平均开采深度为2450m,其中5个达到3500～4100m。随着
In recent years, as the price of gold has risen, world gold production has risen year after year. However, gold output in South Africa reached a record high of 1,000 tons in 1970 and then declined year by year, dropping to 607 tons in 1987 and is expected to drop to 600 tons in 1988. The main reason is: increasing the depth of mining. South Africa has about 40 underground gold mines, mining depth increased by 1000m in the past 20 years. Some gold mines, which account for 60% of the total output, have an average depth of 2450m, of which 5 reach 3500-400m. along with