Planning and Success of Mineral Exploration in the United States

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CP-84-014.pdf

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CP-84-014.pdf

http://eprints.org/relation/isVersionOf https://pure.iiasa.ac.at/id/document/2624 http://eprints.org/relation/isVolatileVersionOf https://pure.iiasa.ac.at/id/document/2624 http://eprints.org/relation/isCoversheetVersionOf https://pure.iiasa.ac.at/id/document/2624 archive 351 disk0/00/00/25/63 2016-01-15 01:55:30 2021-08-27 17:12:10 2016-01-15 01:55:30 monograph show 2 Rose A.W. Eggert R.G. AL0622 Planning and Success of Mineral Exploration in the United States pub iis_ecn iis_min prog_min This paper examines three areas related to metallic mineral exploration in the United States: exploration success over time, the episodic nature of exploration activity for specific minerals, and exploration planning within large corporations. The gross value of metallic mineral discoveries, excluding uranium and iron, exhibits no clear upward or downward trend from 1955 to 1960 in the United States, although large short-term fluctuations in discovery values make discernment of a trend difficult. When exploration cost,= axe compared with these discovery values, the success ratio (gross value of discoveries/exploration costs) appears to decrease over time. Nevertheless, these calculations ,are fraught with uncertainty. Gross values for recent mineral discoveries are difficult to estimate, because it is unclear how many will actually come into production and because initial reserve figures are usually much lower than what ultimately is mined. Moreover, the expenditure data are drawn from a number of sources and must be viewed as estimates, not precise figures. Exploration for copper, molybdenum, iron, gold, and uranium has been episodic over the last 80 years. Surges of activity, lasting for 5 to 15 years, are followed by periods of little exploration. The surges are often caused by increases in demand for a particular metal due to new uses, technologic changes in methods 01 mineral processing that permit different ore types to be used, and new geologic models of mineral occurrence that are used to guide exploration for specific types of deposits. Periods of inactivity result from mineral discoveries that significantly alter the supply of a metal (frequently due to successful exploitation of a new geologic or exploration model), and decreases in demand for a metal due to obsolescence. 1984-04 published CP-84-014 CP-84-014 1854 public collaborative_paper IIASA, Laxenburg, Austria 48 FALSE info:eu-repo/semantics/book