首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 795 毫秒
1.
A vital and indisputable link exists between phosphate rock and world food supply. Phosphate rock is the source of phosphorus used to make phosphatic fertilizers, essential for growing the food needed by humans in the world today and in the future. We modeled the depletion of the known reserves and reserve base (which includes reserves) of phosphate rock based on various scenarios for increasing population and future demand for phosphate. Using these scenarios, the presently known reserves will be depleted within about 50 years, and the remainder of the reserve base will be depleted within the next 100 years. For this model, we used rates of growth of demand for phosphate rock of between 1 and 1.7 percent annually. We also examined demand rates that decrease over time toward demand stasis. Growthrate scenarios that stabilize demand at the year 2100 are little different from unconstrained growth. Demand stabilization by 2025 extends the reserve base by only about 50 years. Additional considerations could affect these depletion scenarios, causing them to be substantially too high or too low. Nonetheless, the incluctable conclusion in a world of continuing phosphate demand is that society, to extend phosphate rock reserves and reserve base beyond the approximate 100 year depletion date, must find additional reserves and/ or reduce the rate of growth of phosphate demand in the future. Society must: 91) increase the efficiency of use of known resources of easily minable phosphate rock; (2) discover new, economically-minable resources; or (3) develop the technology to economically mine the vast but currently uneconomic resources of phosphate rock that exist in the world. Otherwise, the future availability of present-cost phosphate, and the cost or availability of world food will be compromised, perhaps substantially.  相似文献   

2.
The giant oil fields of the world are only a small fraction of the total number of fields, but their importance is huge. Over 50% of the world’s oil production came from giants by 2005 and more than half of the world’s ultimate reserves are found in giants. Based on this, it is reasonable to assume that the future development of the giant oil fields will have a significant impact on the world oil supply. In order to better understand the giant fields and their future behavior, one must first understand their history. This study has used a comprehensive database on giant oil fields in order to determine their typical parameters, such as the average decline rate and life-times of giants. The evolution of giant oil field behavior has been investigated to better understand future behavior. One conclusion is that new technology and production methods have generally led to high depletion rates and rapid decline. The historical trend points towards high decline rates of fields currently on plateau production. The peak production generally occurs before half the ultimate reserves have been produced in giant oil fields. A strong correlation between depletion-at-peak and average decline rate is also found, verifying that high depletion rate leads to rapid decline. Our result also implies that depletion analysis can be used to rule out unrealistic production expectations from a known reserve, or to connect an estimated production level to a needed reserve base.  相似文献   

3.
The geological coal resource of the U.S. is abundant and proved coal reserves are listed as the world’s largest. However, the reserves are unevenly distributed and located in a small number of states, giving them major influence over future production. A long history of coal mining provides detailed time series of production and reserve estimates, which can be used to identify historical trends. In reviewing the historical evolution of coal reserves, one can state that the trend here does not point toward any major increases in available recoverable reserves; rather the opposite is true due to restrictions and increased focus on environmental impacts from coal extraction. Future coal production will not be entirely determined by what is geologically available, but rather by the fraction of that amount that is practically recoverable. Consequently, the historical trend toward reduced recoverable amounts is likely to continue into the future, with even stricter regulations imposed by increased environmental concern. Long-term outlooks can be created in many ways, but ultimately the production must be limited by recoverable volumes since coal is a finite resource. The geologic amounts of coal are of much less importance to future production than the practically recoverable volumes. The geological coal supply might be vast, but the important question is how large the share that can be extracted under present restrictions are and how those restrictions will develop in the future. Production limitations might therefore appear much sooner than previously expected.  相似文献   

4.
The magnitude of the world's mineral consumption has increased sharply, and there is no sign that growth is likely to stop in the near future. Currently, new discoveries and technology add to the reserves of varous mineral commodities at a rate that has exceeded depletion. As a result, life expectancies have remained nearly constant. However, it is questionable whether this condition is sustainable in the future. Therefore, most of our attention to the future has been focused on potentially recoverable resources. The potentially recoverable resources for 35 minerals in the Earth's crust were estimated based on the relationship between crustal abundance and the reserve of currently recoverable gold. The ratio of the reserve plus cumulative consumption to the abundance of gold is appropriate for calculating reserves of other mineral resources because gold has the highest profit margin for exploration of reserves. From an economic perspective, the price of gold is 350 times the mean value of 33 other resources for calculating production versus price. New mining technologies and new processing methods have been developed during the last 20 years as a response to high prices. As a result, five times the reserves available in 1970 have now been discovered, and two times the reserves available in 1970 were consumed during the past two decades. It is questionable whether other mineral commodities can reach the ratio of reserve plus cumulative consumption to abundance that gold does. Using this concept, the limit of the Earth's resources under present technology was calculated for 35 mineral resources, based on the ratio of the reserve plus cumulative consumption to abundance for gold. Even though recoverable tonnage of lead, silver, tin, boron, copper, and mercury from ore deposits in the Earth's crust is relatively low, the abundance of these metals is apparently sufficient for future supplies. However, considering the special situation of gold created by its very high price compared to world production, there is anxiety concerning steep increases in the price or depletion of these metals, which have a shorter lifetime from a geochemical point of view.  相似文献   

5.
This paper examines three issues related to both the U.S. and world oil supply: (1) the nature of the long-term, postpeak production profile for the U.S. and, by inference, other regions (the Hubbert curve is used as a “strawman” model); (2) implications on U.S. energy security of using a modified Hubbert-type conceptual model of prepeak production, testing the adequacy of Latin America to be the primary source of U.S. oil imports; and (3) the cyclic behavior of oil prices. it shows that U.S. production will exhibit a more attenuated decline than that simulated by the Hubbert curve and not decline to zero. it asserts that U.S. production is better predicted by past reserves than past production, but that this argument does not apply to nations that keep a much larger proportion of reserves in the ground. Such nations could considerably expand production without any growth in reserves. The paper concedes that the potential total production for these nations could be examined with a Hubbert curve model linked to reserves, but with great uncertainty. Such an uncertain optimistic forecast predicts that the cumulative production of Latin America could far exceed that of the United States. Nevertheless, a statistical model of oil prices since 1870 implies that real wellhead oil prices in the United States are on a long-term upward path, underlying a much more “noisy” cyclical pattern estimated to include 22- and 27-year cycles. The statistical model predicts a severe oil shock within a few years (of 1998) but also predicts that through 2030, real oil prices will not reach 1981 levels again. The paper examines U.S. and world trends in seismic exploration, drilling locations and depths, drilling costs, oil/gas reserves, oil/gas use rates, and oil demand. After taking these factors into consideration, it concludes that the statistical model of oil prices cannot be disputed, despite its lack of basis in economic theory.  相似文献   

6.
Although reserve (or field) growth has proved to be an important contributing factor in adding new reserves in mature petroleum basins, it is a poorly understood phenomenon. Although several papers have been published on the U.S. fields, there are only a few publications on fields in other petroleum provinces. This paper explores the reserve growth in the 42 largest West Siberian oil fields that contain about 55% of the basin's total oil reserves.The West Siberian oil fields show 13-fold reserve growth 20 years after the discovery year and only about 2-fold growth after the first production year. This difference in growth is attributed to extensive exploration and field delineation activities between discovery and the first production year. Because of the uncertainty in the length of evaluation time and in reported reserves during this initial period, reserve growth based on the first production year is more reliable for model development. However, reserve growth models based both on discovery year and first production year show rapid growth in the first few years and slower growth in the following years. In contrast, the reserve growth patterns for the conterminous United States and offshore Gulf of Mexico show a steady reserve increase throughout the productive lives of the fields. The different reserve booking requirements and the lack of capital investment for improved reservoir management and production technologies in West Siberia are the probable causes for the difference in the growth patterns.The models based on the first production year predict that the reserve growth potential in the 42 largest oil fields of West Siberia for a five-year period (1998–2003) ranges from 270–330 million barrels or 0.34–0.42% per year. For a similar five-year period (1996–2001), models for the conterminous United States predict a growth of 0.54–0.75% per year.  相似文献   

7.
The last 50 years saw a dramatic increase in living standards and improvement in the quality of life for many of the world’s poorest. Mortality rates fell, life expectancy rose and per capita incomes swelled. That improvement has been underpinned by technological development and the ubiquitous use of metal and mineral resources. To maintain such progress while addressing climate change and a rising world population, sustainable sources of raw materials will be required, in both developed and developing countries. Delivering the UN Agenda 2030 with its seventeen Sustainable Development Goals and implementing the Paris Agreement of December 2015 will require technologies that consume both traditional and new minerals. Metal recycling and technological change will contribute, but mining must continue and grow for the foreseeable future. Of the 200 or so countries in the world, 60 are open to large-scale mining but 140 are not. New resource governance linkages are needed between existing institutional frameworks so that continuity of global mineral supply is assured over coming decades. Such arrangements would oversee responsible sourcing of minerals, directions of mineral exploration and sustainability of mining and ore processing, raising of consumer awareness and sharing the wealth generated by mining more fairly.  相似文献   

8.
钾盐资源全球分布和我国找钾实践及方法探究   总被引:4,自引:2,他引:4       下载免费PDF全文
世界各国大型古代海相固体钾盐矿床多数是在石油、盐岩矿、盐泉卤水等资源的勘查过程中被发现的。国内几十年的找钾实践证实,我国缺乏大型海相固体钾盐矿床,近年来在新生代陆相沉积盆地中寻找大型固体钾盐矿床的努力也没有取得明显进展。我国已探明的钾盐储量主要分布在青海柴达木盆地和新疆罗布泊的11个盐湖及其晶间卤水中,约占资源总量的90%以上;以固体钾矿赋存的资源量少且品位不高,仅占己知总量的2.6%。从1958年察尔汗盐滩生产出第一批953吨钾肥填补我国钾肥生产的空白,到年产150万吨KCl的卤水钾盐开发规模的形成;从1995年在罗布泊发现大型卤水钾矿,到2008年预期生产120万吨K2SO4,显示了我国干旱区盐湖卤水钾盐资源的重要位置。有专家建议,今后的工作应在深入研究成盐盆地基底构造和岩相古地理的基础上,进一步划分可能成钾的次级盆地并进行重点勘探和研究。借鉴世界各国找钾经验,将地质观察分析、地球物理探测、地球化学与水化学等方法综合运用,我国的探盐找钾工作有可能取得突破性进展。  相似文献   

9.
非洲在世界石油供给格局中的地位演变   总被引:1,自引:0,他引:1  
郝丽莎  赵媛 《地理研究》2012,31(3):507-520
21世纪以来,非洲已成为世界石油进口大国寻求来源地多元化、保障自身石油安全的战略高地,也成为我国的第二大石油来源地。考察非洲在世界石油供给格局中的地位及演变,有利于系统把握非洲石油供给的优劣势,为优化我国对非石油合作战略提供依据。本文以国家为研究单元,综合运用箱线图和空间聚类分析法,创新份额和位序综合分析法,对比考察了...  相似文献   

10.
世界钢铁工业发展趋势及对我国钢铁工业的影响   总被引:7,自引:1,他引:6  
20世纪是世界钢铁工业快速发展的世纪。在科技进步和市场需求的拉动下,世界钢铁生产的规模、地区格局与原材料供应等都发生了显著变化。进入21世纪,世界钢铁工业将在高科技的推动、原材料供给与产品销售的激烈竞争、以及环境容量的制约下,进入新的结构调整和发展时期。未来世界钢铁工业将以发展中国家的增长为主;生产体制从注重产量向环境友好转化;市场竞争将加速跨国公司全球资本重组。我国钢铁工业在今后20至30年内仍有较大发展空间,国内外市场需求的变化与跨国公司的并购重组,将推动我国钢铁工业布局进一步接近市场,向沿海或大都市周边地区集中。  相似文献   

11.
Industrial, technological, and economic developments depend on the availability of metallic raw materials. As a greater fraction of the Earth’s population has become part of developed economies and as developed societies have become more affluent, the demand on metallic mineral resources has increased. Yet metallic minerals are non-renewable natural resources, the supply of which, even if unknown and potentially large, is finite. An analysis of historical extraction trends for eighteen metals, going back to the year 1900, demonstrates that demand of metallic raw materials has increased as a result of both increase in world population and increase in per-capita consumption. These eighteen metals can be arranged into four distinct groups, for each of which it is possible to identify a consistent pattern of per-capita demand as a function of time. These patterns can, in turn, be explained in terms of the industrial and technological applications, and in some cases conventional uses as well, of the metals in each group. Under the assumption that these patterns will continue into the future, and that world population will grow by no more than about 50% by the year 2100, one can estimate the amount of metallic raw materials that will be required to sustain the world’s economy throughout the twenty-first century. From the present until the year 2100, the world can be expected to require about one order of magnitude more metal than the total amount of metal that fueled technological and economic growth between the age of steam and the present day. For most of the metals considered here, this corresponds to 5–10 times the amount of metal contained in proven ore reserves. The two chief driving factors of this expected demand are growth in per-capita consumption and present-day absolute population numbers. World population is already so large that additional population growth makes only a small contribution to the expected future demand of metallic raw materials. It is not known whether or not the amount of metal required to sustain the world’s economy throughout this century exists in exploitable mineral resources. In the accompanying paper, I show that it is nevertheless possible to make statistical inferences about the size distribution of the mineral deposits that will need to be discovered and developed in order to satisfy the expected demand. Those results neither prove nor disprove that the needed resources exist but can be used to improve our understanding of the challenges facing future supply of metallic raw materials.  相似文献   

12.
The rare earth elements (REE) have attracted much attention in recent years, being viewed as critical metals because of China’s domination of their supply chain. This is despite the fact that REE enrichments are known to exist in a wide range of settings, and have been the subject of much recent exploration. Although the REE are often referred to as a single group, in practice each individual element has a specific set of end-uses, and so demand varies between them. Future demand growth to 2026 is likely to be mainly linked to the use of NdFeB magnets, particularly in hybrid and electric vehicles and wind turbines, and in erbium-doped glass fiber for communications. Supply of lanthanum and cerium is forecast to exceed demand. There are several different types of natural (primary) REE resources, including those formed by high-temperature geological processes (carbonatites, alkaline rocks, vein and skarn deposits) and those formed by low-temperature processes (placers, laterites, bauxites and ion-adsorption clays). In this paper, we consider the balance of the individual REE in each deposit type and how that matches demand, and look at some of the issues associated with developing these deposits. This assessment and overview indicate that while each type of REE deposit has different advantages and disadvantages, light rare earth-enriched ion adsorption types appear to have the best match to future REE needs. Production of REE as by-products from, for example, bauxite or phosphate, is potentially the most rapid way to produce additional REE. There are still significant technical and economic challenges to be overcome to create substantial REE supply chains outside China.  相似文献   

13.
A geochemical evaluation of the Szc-Halimba-Kisld area, Hungary, covering an area of more than 200 km2 is presented using different statistical and geostatistical methods. The study area is a representative example of allochtonous karst bauxite accumulation. The three groups of deposits studied here have been explored and mined since 1950. Several thousand boreholes have been drilled, and bauxite cores were analyzed for the five main chemical components. A total of 80,000 pleces of analytical data were processed, followed by a geological examination of borehole logs and of mining excavations.The quantitative geochemical evaluation of the data set led to both geochemical and practical results: The geochemical behavior of the allochtonous, clastic karst bauxite deposits differs essentially from that of the autochtonous and parautochtonous ones, as well as that of the lateritic bauxite deposits. The deposits of the study area can be split into several subsequent geochemical-sedimentological units, each representing an event of bauxite transport and accumulation. Clear regional patterns can be revealed in the composition of these units. The geostatistically measured chemical variability of the geochemical units is rather different, the lowest units showing the smallest variability. The interrelations of the main chemical components are weaker and more irregular in the studied deposits than in the autochtonous lateritic bauxite deposits. Additional local genetic features, such as transport routes, can be delineated by the methods applied. Within each deposit, local changes of chemical composition and of its variability can be determined more precisely. These results can be used in bauxite prospecting and exploration, because areas of high or low bauxite quality can be predicted.  相似文献   

14.
Fossil fuels are finite and nonrenewable. In due course, they will become scarce and costly. Their role in powering modern economies is so vital as to warrant a review of ultimately recoverable reserves and of plausible future consumption patterns. Over the past 50 years, many oil companies, geologists, governments, and private corporations have performed scores of studies of Estimated Ultimately Recoverable (EUR) global oil. Taken together, the great majority of these studies reflect a consensus that EUR oil reserves lie within the range of 1800 to 2200 billion barrels. Given this range, a simple model is used to calculate that world oil production is likely to peak sometime between 2007 and 2019. The global transportation sector, almost totally dependent on oil, could be especially hard hit unless vehicles fueled by sources other than petroleum are developed and rapidly deployed.  相似文献   

15.
This article examines the Hotelling model of optimal nonrenewable resource extraction in light of empirical evidence that petroleum and minerals prices have been trendless despite resource scarcity. In particular, we examine how endogenous technology-induced shifts in the cost function would have evolved over time if they were to maintain a constant market price for nonrenewable resources. We calibrate our model using empirical data on world oil, and find that, depending on the estimate of the initial stock of reserve, oil reserves will likely be depleted some time between the years 2040 and 2075.  相似文献   

16.
Cobalt is obtained mainly as a byproduct of the mining and metallurgical processing of copper and nickel. The amount of minable cobalt has a characteristic supply limit, which is dependent upon demand for copper and nickel. It is considered that cobalt consumption will be affected by the amount mined in the near future, because world demand has been gradually increasing, while the production from copper sulfide ores in Zaire and Zambia, major producing countries, has decreased for political, economical and technological reasons. The world demand for cobalt has surpassed the world mine production, and cobalt sales from the National Defense Stockpile of the United States and exports from Russia and cobalt recovered from stockpiled intermediates contributed to the supply in 1994. It is concluded, from a statistical point of view, that this trend of shortage and high prices for cobalt will continue in the near future.  相似文献   

17.
Predicting the Peak in World Oil Production   总被引:1,自引:0,他引:1  
The US Department of Energy's Energy Information Administration (EIA) recently predicted that world oil production could continue to increase for more than three decades, based on the recent US Geological Survey (USGS) evaluation of world oil resources and a simple, transparent model. However, it can be shown that this model is not consistent with actual oil production records in many different regions, particularly that of the US, from which it was derived. A more careful application of the EIA model, using the same resource estimates, indicates that at best non-OPEC oil production can increase for less than two decades, and should begin to decline at the latest sometime between 2015 and 2020. OPEC at this point will completely control the world oil market and will need to meet increased demand as well as compensate for declining production of non-OPEC producers. OPEC could control the market even sooner than this, given its larger share of proven oil reserves, probable difficulties in transforming non-OPEC undiscovered reserves into proven reserves, and the converging interests of all oil producers as reserves are depleted. This has significant implications for the world economy and for US national security.  相似文献   

18.
The USGS has developed several mathematical models to forecast reserve growth of fields both in the United States (U.S.) and the world. The models are based on historical reserve growth patterns of fields in the U.S. The patterns of past reserve growth are extrapolated to forecast future reserve growth. Changes of individual field sizes through time are extremely variable, therefore, the reserve growth models take on a statistical approach whereby volumetric changes for populations of fields are used in the models. Field age serves as a measure of the field-development effort that is applied to promote reserve growth. At the time of the USGS World Petroleum Assessment 2000, a reserve growth model for discovered fields of the world was not available. Reserve growth forecasts, therefore, were made based on a model of historical reserve growth of fields of the U.S. To test the feasibility of such an application, reserve growth forecasts were made of 186 giant oil fields of the world (excluding the U.S. and Canada). In addition, forecasts were made for these giant oil fields subdivided into those located in and outside of Organization of Petroleum Exporting Countries (OPEC). The model provided a reserve-growth forecast that closely matched the actual reserve growth that occurred from 1981 through 1996 for the 186 fields as a whole, as well as for both OPEC and non-OPEC subdivisions, despite the differences in reserves definition among the fields of the U.S. and the rest of the world.  相似文献   

19.
This study employs (1) a simple econometric model to generate a time series of drilling footage to the year 2040 and (2) learning models to estimate the oil reserve additions from that drilling, given scenarios of oil price and projected U.S. population. Reserve additions are estimated separately for the lower 48 states and Alaska regions by estimating separate drilling footage and learning models for each region. Generally, the estimates of potential supply from undiscovered oil fields and from extensions of known fields are more optimistic than recent estimates by others. For a $1989 price of about $20/barrel (bbl), which is similar to recent prices, the potential supply of oil is estimated to be approximately 60.7 billion bbl, with 95-percent confidence bounds of 54.3 and 67.1 billion bbl. For a price of $25.50/bbl, potential supply is estimated to be approximately 82 billion bbl, with 95-percent confidence bounds of 74.5 and 89.5 billion bbl. Although estimates of potential oil supply for the entire United States are more optimistic than other recent estimates, the part of that supply estimated to be forthcoming from Alaska is smaller than other recent estimates: 2.3 and 3.3 billion bbl for prices of about $20 and $25.50 per barrel, respectively. Thus, reserve additions from the lower 48 states through development drilling and through improved recovery and production technologies will become increasingly important to future U.S. oil supply.  相似文献   

20.
This paper shows that there is a strict quantitative connection between three factors: reserves-to-production ratio (w), rate of production growth (a), and degree of reserve replenishment during 1 year (i). The first of these factors shows how many years the current level of production can be supported by existing proved reserves (if both are invariable). The second factor shows how quickly the production increases. The third, characterizes the correlation between oil production and reserves discovery, which is the basis for potential oil production growth. For planning purposes it is important to know how many units of new reserves have to be proved during each year per one unit of production for the different reserves-to-production ratio and production growth. The results of calculating these factors are shown in the table and pictured on the graph. They can be used for regions where the replenishment of proven reserves (factor (i)) exceeds 1 barrel of new reserves per 1 barrel of production. This paper also describes the interdependence and dynamics of these factors when the replenishment of proved reserves is incomplete.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号