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1.绪言在资本主义国家中,由1972年到1976年五年期间探矿及开发矿山投资总额为500亿美元以上(主要是金属矿物)。每年采矿量约100亿吨,其中65%为露天开采。金属矿石量为21亿吨。年产15万吨以上的矿山1,018处。有人认为,虽然露天开采有很多优点,但是由于环境保护等原因,本来大力发展露天开采,而今后可能大力发展地下开采。地下开采的生产率低、成本高、作业条件不好,这是第二次世界大战以后原来的地下开
1. INTRODUCTION In capitalist countries, the total investment in prospecting and development of mines during the five years from 1972 to 1976 was over 50 billion U.S. dollars (mainly metallic minerals). Approximately 10 billion tons of ore are harvested each year, of which 65% is open pit mining. The amount of metal ore is 2.1 billion tons. 1,018 mines with an annual output of more than 150,000 tons. Some people think that although open pit mining has many advantages, due to environmental protection and other reasons, open-pit mining has been vigorously developed and underground mining may be vigorously developed in the future. Underground mining low productivity, high cost, poor working conditions, which is the underground after the Second World War opened