为了查明在今后25年间铜工业的发展情况,最近美国矿产局组织了一次调查研究。他们把铜工业分解为勘探、开采、选矿、冶炼、精炼和废铜回收六个方面,并委托一个矿业公司进行调查。在调查过程中,先由一个研究小组根据他们的知识和经验,编制了一个包括47项调查项目的项目表,其中有三项是属于地质勘探方面的。这三项为: In order to find out the development of the copper industry in the next 25 years, the United States Mineral Resources Bureau recently organized a survey. They broke down the copper industry into six aspects of exploration, mining, mineral processing, smelting, refining, and scrap copper recycling, and commissioned a mining company to investigate. In the investigation process, a research team first compiled a project list including 47 investigation items based on their knowledge and experience, of which three were geological surveys. The three items are: