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The analysis of various factors influencing mineral availability documents future short-and long-term mineral-commodity supply trends. The lifetime of reserves, the development of the relative importance of production centres and the forecasting of the depletion of a resource base are mainly geological factors, although the category “reserves”, in contrast to “resources”, is determined by technical and economical aspects. These three factors govern the short-and long-term supply of mineral commodities. The intensity-of-use factors and the growth rate of consumption are variables related to the demand of mineral commodities. They influence the decision of companies for certain commodities as targets for exploration and investment in production centres. Both factors control the short-to medium-term mineral supply. Finally, the lead time to production is a technical variable, although influenced by ore deposit type, and controls short-term mineral availability. 相似文献
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Sustainable development and the exploitation of mineral and energy resources: a review 总被引:9,自引:0,他引:9
Natural resources, e.g., metals, industrial minerals, water, and soil, are the essential basis for our economy and well-being. We have to know where these raw materials come from and how they are mined. Sustainable development requires the maintenance, rational use and enhancement of natural resources, as well as a balanced consideration of ecology, economy and social justice. Four general rules concerning the implementation of sustainable development for renewable and non-renewable resources are discussed. Examples of the consumption of selected materials from historical times to the present day are presented, as well as of regional distribution, usage (in contrast to consumption), lifetimes of resources, the supply-and-demand cycle, recycling and substitution in modern times. To fulfill the requirement of sustainable development, the efficiency with which resources are utilized has to be improved. The learning process, often driven by financial rewards, leads from one technology to a better one, thus increasing the efficiency of the use of a resource or commodity. Examples of learning curves are discussed. Industrial countries have to transfer their advanced technologies to developing countries in order to avoid undesirable development in the mining industry and use of natural resources in those regions. The use of the best available technology by the mining industry, taking into account economic considerations, and the necessity to establish environmental guidelines are essential if environmental impact of the production of non-renewable resources is to be minimized. Far more critical than the production of non-renewable resources under the aspect of sustainable development and the capacity of the pollutant sinks of the Earth is the element of natural attenuation with regard to the resources soil and water. 相似文献
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This paper elaborates in what way a dynamic perspective on reserves, resources and geopotential is necessary to provide robust estimates on resource availability. We introduce concepts of essentiality, criticality and economic scarcity and discuss for the case of phosphorus (P) how they are defined and may be measured. The case of P is considered in detail as P an essential element for global food security with a highly dissipative use and is geographically unevenly distributed across the globe. We distinguish and relate the complementarity between physical and economic scarcity and discuss limits and potential of static indicators such as static lifetime, Hubbert curve applications, and the Herfindahl–Hirschman-Index of P for predicting future availability of these resources. We reveal that these static indicators are – in general – not valid approaches to predict physical scarcity of resources. Geological data show that though the P reserves have not been systematically and completely assessed on a global scale, the static lifetime of P is high. When acknowledging socio-economic and technological dynamics, and available geological facts, statements predicting physical scarcity or a peak in P production within a few decades are unlikely to be accurate or valid. We elaborate that some simplified indicators such as static lifetime or the Hubbert curve based prediction of peaks may serve as screening indicators preceding early warning research, which may induce increased mining activities, technology innovation or other actions. However, in general, these simplified indicators are not valid approaches to predict physical scarcity of resources. Although one day there may be a supply-driven P production peak, demand-driven production plateaus and multiple peaks are probable in the near future. Given its geopotential, essentiality, and the learning curve of efficient fertilizer use, P is subject to demand-driven market dynamics. Thus, a symmetric decline and unavoidable shortage of P in the next decades are unlikely. This insight does not refute the need to close the anthropogenic P loop. Activities associated with P production and consumption use has a significant pollution potential in part because of the dissipative nature. The paper reveals the necessity to mitigate risks (such as economic scarcity, especially for poor farmers) of both short-term price peaks and longer lasting step-changes in price, e.g. due to knowledge gaps of technological adaptation in energy and water management or other reasons of insufficient supply-demand dynamics management. The complexity of this task necessitates a transdisciplinary approach. 相似文献
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Unconventional PGE occurrences and PGE mineralization in the Great Dyke: metallogenic and economic aspects 总被引:4,自引:0,他引:4
B. Stribrny F. -W. Wellmer K. -P. Burgath T. Oberthür M. Tarkian T. Pfeiffer 《Mineralium Deposita》2000,35(2-3):260-280
Platinum group elements (PGE) are strategic materials because 96–99% of the world production is derived from just five mining
districts and because they cannot be replaced as catalysts in many chemical processes. In order to lessen the strategic character
of PGE, both conventional deposits and unconventional PGE mineralizations were investigated in an attempt to locate viable
deposits which would diversify the supplier base. In the Great Dyke, conventional PGE mineralization occurs in the form of
pristine sulfide ores mined underground and oxidic surface ores. New observations such as bimodal distributions of the PGE
in the Main Sulfide Zone (MSZ), elevated Pt/Pd ratios in the oxidized MSZ compared to the sulfidic part and distinct differences
between the platinum group mineral (PGM) assemblages of the MSZ and stream sediments of adjacent rivers emphasize the fact
that even though the Great Dyke seems to be the second or third largest PGE occurrence in the world, the complicated PGE distributions
and supergene redistributions should be kept in mind during planning and mine operation. Investigations of unconventional
PGE occurrences in ophiolites, Alaskan-type intrusions, porphyry copper deposits and in the Kupferschiefer show that economically
exploitable PGE concentrations can be expected in a broader variety of host rocks than considered favourable in the past.
In the Albanian Mirdita ophiolite average contents of 860 ppb Pt and 60 ppb Pd were detected. Flotation concentrates of porphyry
copper deposits, for example from Mamut, Malaysia, Santo Tomas, Philippines, Elacite, Bulgaria, and Ok Tedi, Papua New Guinea,
contain between 827 and 1860 ppb Pd + Pt. In selected profiles of the Polish Kupferschiefer average contents of 255 ppb Pt,
94 ppb Pd, 2.4 ppm Au and 13.0 ppm Ag were analysed. The distribution of the PGE resources in the world and the annual production
rates, however, underline the fact that the chances for a significant change in the supplier base are relatively low. The
Bushveld Complex will remain the largest producer, followed by Noril'sk-Talnakh, Sudbury and Stillwater. If the operations
in the Great Dyke reach their planned capacities, the Great Dyke will rank in third place among the PGE-producing deposits
in the world.
Received: 12 September 1998 / Accepted: 7 December 1999 相似文献