Global Mine Research Articles

Locus of control over global mine production– developments between 1985 and 2018 against a historical background

AbstractIt is a well-known fact that mine production has shifted from the industrialised countries of Europe, North America and Japan to emerging economies in Latin America, Africa and Asia and to Australia since the mid-20th century. The lack of self-sufficiency or high import dependence, in particular of the so-called critical metals, has become an issue of great political concern in these industrialised countries over the past 15 years. This study of six metals, cobalt, copper, iron ore, lithium, manganese and rare earths, contrasts this picture of geographical location of production with an analysis of where the control over mine production around the world is based, which we call the locus of control. Production might have moved out of the industrialised countries but control over production by companies based in the industrialised countries remains and has even increased between 1985 and 2018. We measure control as share of the total value of the production of the six metals. European transnational mining companies have increased their control from 14 to 18% while mining companies based in North America have lost control, a decline from 13 to 8%. When Australian companies, that have more than tripled their control in the same period, are added, control by the industrialised countries has increased to 44% of these six metals. Companies based in Latin America, Africa and Asia excluding China, taken together have maintained their control level, roughly a third of the total value of the six metals. Inside this group of countries African share has dwindled from 12 to 3% while Asian companies have more than doubled their share from 5 to 12%. Control by mining companies based in the republics of the former Soviet Union have been reduced from 25 to 7% while in the same period Chinese companies’ control has doubled from 6 to 12% of the total value of these six metals. Countries in Asia (excluding China) together with Latin American and African countries produce 51% of these six metals measured by the value at the mine stage. However, companies based in these countries control not more than 33% of the production.

Global mining footprint mapped from high-resolution satellite imagery

Mining is of major economic, environmental and societal consequence, yet knowledge and understanding of its global footprint is still limited. Here, we produce a global mining land use dataset via remote sensing analysis of high-resolution, publicly available satellite imagery. The dataset comprises 74,548 polygons, covering ~66,000 km2 of features like waste rock dumps, pits, water ponds, tailings dams, heap leach pads and processing/milling infrastructure. Our polygons finely contour the edges of mine features and do not include the space between them. This distinguishes our dataset from others that employ broader definitions of mining lands. Hence, despite our database being the largest to date by number of polygons, comparisons show relatively lower global land use. Our database is made freely available to support future studies of global mining impacts. A series of spatial analyses are also presented that highlight global mine distribution patterns and broader environmental risks.

Decarbonisation to drive dramatic increase in mining waste–Options for reduction

Global demand for energy transition metals is expected to lead to an intensification of mining activities and an increase in associated land disturbance and mine waste volumes. This paper forecasts global mine waste generation for four metals needed in batteries: copper, lithium, manganese, and nickel, and finds that waste volumes are likely to rise exponentially. Alternative extractive processes are required to achieve consequent waste reduction. Beneficial reduction outcomes include (1) smaller volumes and footprint area, (2) lower toxicity and chronic contamination, and (3) lower risk of catastrophic tailings dam failures. This paper reviews six mining and processing innovations that, if taken in combination, may achieve the needed reduction: mine waste (re)processing, environmental desulphurisation, dry-stacking and co-mingling, preconcentration and coarse particle flotation, ore-sand co-production, and in-situ recovery. None of these approaches can tackle the mine waste challenge individually, and the choice of method is site-dependent but, together, they provide promising alternatives to the current, increasingly wasteful mining practices.

Non-renewable resource extraction over the long term: empirical evidence from global copper production

Global mine production of copper has risen more than 80 times over the last 135 years. What were the main drivers? I examine this question based on copper market data from 1880 to 2020. I employ a structural time series model with sign restrictions to identify demand and supply shocks. I find that a deterministic trend drives most of the output growth. At the same time, unpredictable demand and supply shocks caused substantial fluctuations around the trend. A global commodity demand shock that is, for example, linked to a 3% unexpected expansion of the global economy due to rapid industrialization causes a 10% rise in the real copper price, incentivizing a 5% increase in global copper production. This provides empirical evidence for the feedback control cycle of mineral supply.

Regional Distribution and Causes of Global Mine Tailings Dam Failures

Tailings ponds are one of the three major production facilities in metal mines. The volume of tailings increases year by year, but the storage capacity of existing tailings ponds is limited. Therefore, tailings dams must become more fine-grained and larger. The potential hazard they represent should not be underestimated. This paper reveals the causes and regional distribution patterns of 342 tailings dam failures globally from 1915 to 2021 through statistical analysis. It was found that tailings pond failures occur almost every year, with an average of 4.4 accidents/year (1947–2021). The frequency has been gradually increasing in recent years, and most tailings pond failures are directly related to heavy rainfall or earthquakes. The frequency of tailings pond failures was significantly higher in Asia (21.3%) and the Americas (57.9%), especially in China (n = 43) and the United States (n = 107). Causes of tailings pond failures differed among regions. Most tailings pond failures in Asia and Europe were related to hydroclimate, while those in South America were mainly triggered by earthquakes. This study will provide theoretical data for the pre-design as well as the safe and stable operation of global tailings ponds, which will help to prevent global tailings pond failures.

Characterizing end-of-life household vehicles’ generations in China: Spatial-temporal patterns and resource potentials

China is now boasting a huge number of end-of-life vehicles (ELVs) with a low recovery rate, resulting in a waste of resources and severe environmental pollution. Predicting the generation of ELVs in future helps to enhance recycling efficiency by providing a basis for the planning of recycling industry. However, previous research did not provide a detailed, mid-term forecast. Based on a stocks-driven model and the bottom-up extrapolation of in-use stocks, this study characterizes the generation of end-of-life household vehicles (HVs) in China by addressing the detailed spatial-temporal patterns and resource potentials during 2019–2050. The results show that the annual end-of-life HVs in China will continuously increase during 2019–2050, resulting an accumulated 1.48 billion units, among which urban areas will account for 86%, and internal combustion engine vehicles (ICEVs) will take up 80%. Regarding the spatial patterns, eastern region will possess the largest proportion, and wide variations are found among all provinces due to the difference in population size and economic development level, which have important implications for further planning of end-of-life HVs recycling industry. Before 2050, accumulated quantity of all types of metals in end-of-life HVs will approach domestic mine production (in 2019), or even approach the current global mine production, indicating they have a great potential as an indispensable source for domestic resource supply.

A global-scale spatial assessment and geodatabase of mine areas

Despite massive growth in mining activity worldwide, efforts to assess the land use of mining at a global scale have been limited. Increasing satellite image quality and accessibility now permit detailed assessments of mine areas and their emerging geographical patterns. In this study, we produce a global-scale geospatial dataset of mine areas, comprised of 24,605 mine area polygons, mapped with high spatial precision in satellite imagery across 117 countries. Our dataset adds comprehensive detail on the global distribution, areal extent, and spatial form of mine areas, as well as new understandings of potential risks to surrounding areas. Our results reveal a total occupied land area of ~31,396.3 km 2 , averaging 1.3 km 2 per site. To illustrate potential insights enabled by our datasets, we performed detailed assessments of the geographical distribution of global mine areas in terms of their spatial density, elevations, and areas relative to rivers basins, climate zones, and human development factors. Our study promotes increasing access to high-quality spatial data to facilitate more systematic global management of mine wastes, pollution and mine land management. • 24,605 mine area polygons are delineated across 117 countries, covering 31,396.3 km 2 , at an average of 1.3 km 2 per site. • The spatial distribution of minareas differs between regions, with the highest spatial densities of mining (>100/1000 km 2 ) situated in the North China Plain and Western Australia. • Mine wastes are mostly (46.9%) situated from sea level to 400 m elevation, with an exponential decrease between 400 m and 650 m, linear decrease from 650 m to 2250 m, and the lowest occupancy above 2250 m. • Mine areas relative to rivers basins, climate zones, and human development factors are also explored.

Stability modeling of complex underground mine openings integrating point clouds and FEM 3D

The stability analysis of underground mine systems with complex 3D geometry is still a challenging task, especially when abandoned mines are planned for new uses with public access, that imply more restrictive safety requirements. This inherently multi-scale problem requires both the evaluation of the global mine stability and the assessment of local deformation and failure mechanisms of individual pillars or roof sectors in a robust 3D modeling framework. We integrated 3D remote survey techniques and FEM 3D modeling to perform a comprehensive stability analysis of an abandoned fluorite mine system in the central Southern Alps (Italy), including ten levels excavated in bedded limestones. We reconstructed the 3D geometry of three levels undergoing a reuse plan, combining a dynamic LiDAR system and close-range photogrammetry. We used point clouds in a workflow to generate solids, excavate the 3D analysis domain and generate a FEM 3D mesh for numerical modeling. We performed a series of continuum-based FEM 3D simulations of mine excavation and rock mass strength degradation. Our results allowed assessing the global stability of the abandoned mine and identifying critically stressed roof sectors and pillars to prioritize the local-scale analysis, remediation and monitoring of critical spots.

Geochemical Classification of Global Mine Water Drainage

This paper evaluates the geochemical distribution and classification of global Acid Mine Drainage (AMD) sources. The geochemical compositions of AMD from 72 mine water sites in 18 countries across 6 continents were referenced from literature. The secondary data were analysed for statistical distribution and mine water classification against the Hill (1968) framework. The research found that the global mine water displayed geochemical concentrations within 2%, 11%, 5%, 9% and 8% of the aluminium, sulphate, acidity, total iron and zinc distribution ranges, respectively, at the 75th percentile. The study also found that 46%, 11.1% and 2.7% of mine water sites met the criteria for Class I, Class II and Class III of the Hill (1968) framework, respectively, while the remaining 40% of sites were omitted by the framework’s geochemical specifications. The results were used to optimise the Hill (1968) framework. The revised framework was proposed for effective AMD geochemical classification, regulation and remediation.

Chinese control over African and global mining\u2014past, present and future

Chinese companies are far from taking control over African or global mining. In 2018, they control less than 7% of the value of total African mine production. Chinese investments in African mining of non-fuel minerals between 1995 and 2018 have contributed to production growth but it has also increased Chinese control over African mineral and metal production. There is evidence pointing to a continued Chinese expansion in African minerals and metals but at a slower pace than in the past decade. Through a detailed analysis of every mine, fully or partially controlled by Chinese interest in Africa and all other parts of the world the paper also measures total Chinese control over global mine production to be around 3% of the total value.

Self-adaptive global mine blast algorithm for numerical optimization

In this article, a self-adaptive global mine blast algorithm (GMBA) is proposed for numerical optimization. This algorithm is designed in a novel way, and a new shrapnel equation is proposed for the exploitation phase of mine blast algorithm. A theoretical study is performed, which proves the convergence of any typical shrapnel piece; a new definition for parameters values is defined based on the performed theoretical studies. The promising nature of newly designed exploitation idea is verified with the help of multiple numerical experiments. A state-of-the-art set of benchmark problems are solved with the proposed GMBA, and the optimization results are compared with seven state-of-the-art optimization algorithms. The experimental results are statistically validated by using Wilcoxon signed-rank test, and time complexity of GMBA is also calculated. It has been justified that the proposed GMBA works as a global optimizer for constrained optimization problems. As an application to the newly developed GMBA, an important data clustering problem is solved on six data clusters and the clustering results are compared with the state-of-the-art optimization algorithms. The promising results claim the proposed GMBA as a strong optimizer for data clustering application.

Production weighted water use impact characterisation factors for the global mining industry

Abstract Methods for quantifying the impacts of water use within life cycle assessment have developed significantly over the past decade. These methods account for local differences in hydrology and water use contexts through the use of regionally specific impact characterisation factors. However, few studies have applied these methods to the mining industry and so there is limited understanding regarding how spatial boundaries may affect assessments of the mining industry's consumptive water use impacts. To address this, we developed production weighted characterisation factors for 25 mineral and metal commodities based upon the spatial distribution of global mine production across watersheds and nations. Our results indicate that impact characterisation using the national average ‘Water Stress Index’ (WSI) would overestimate the water use impacts for 67% of mining operations when compared to assessments using watershed WSI values. Comparatively, national average ‘Available Water Remaining’ (AWaRe) factors would overestimate impacts for 60% of mining operations compared to assessments using watershed factors. In the absence of watershed scale inventory data, assessments may benefit from developing alternative characterisation factors reflecting the spatial distribution of commodity production across watersheds. The results also provide an indication of the commodities being mined in highly water stressed or scarce regions.

Personnel location oriented global mine tunnel network modeling

Personnel location oriented global mine tunnel network modeling

Gold and Uranium Occurrences in Quartz-Pebble Conglomerate of Iron Ore Group, Bagiyabahal-Baratangra Area, Sundargarh District, Odisha, India

India is deficient in both gold and uranium resources. Almost one-third of the annual global mine production of ~2500 tonnes of gold is imported into India to fulfil the high gold consumption. Uranium is important for production of nuclear energy, more specifically to execute the country's ambitious programme to generate 20 GW of electricity by 2020.

Criticality Assessment of Metals for Japan’s Resource Strategy

Criticality assessment of metals has been developed to analyze a country’s supply risk and vulnerability to supply restriction. This study presents Japan’s criticality of 22 metals during 2012. Whereas a past assessment focused only on minor metals, evaluation targets here included both common and minor metals. In addition, a new analytic method included mineral interest sufficiency as a criticality component. The evaluation framework developed in this study included 13 criticality components within five risk categories: supply risk, price risk, demand risk, recycling restriction, and potential risk. Weighting factors were used to aggregate components into a single score. This framework reflects a recent government announcement about Japan’s resource strategy. High criticality was found for neodymium, dysprosium, and indium due to a recent increase in demand. Niobium also had high criticality due to production concentration in Brazil. There were few differences in the aggregated criticality scores between the other minor metals and common metals. For minor metals, aggregated criticality was mainly increased by production concentration and recycling difficulty. For common metals, aggregated criticality was increased by short depletion time and growth in global mine production. Compared with a previous study, in 2012 the criticality of tungsten and tantalum were lower due to reduced domestic demand. The analytic methods and results presented in this study will be useful in developing Japan’s resource strategy. [doi:10.2320/matertrans.M2014380]

Modeling Fossil Energy Demands of Primary Nonferrous Metal Production: The Case of Copper

The methodologies for life cycle impact assessment (LCIA) of metal resources are rather diverse. Some LCIA methods are based on ore grade changes, but they typically do not consider the impact of changes in primary metal extraction technology. To characterize the impact of technology changes for copper, we modeled and analyzed energy demand, expressed in fossil energy equivalents (FEE) per kilogram of primary copper, taking into account the applied mining method and processing technology. The model was able to capture variations in reported energy demands of selected mining sites (FEE: 0.07 to 0.84 MJ-eq/kg ore) with deviations of 1 to 30%. Applying the model to a database containing global mine production data resulted in energy demand median values of around 50 MJ/kg Cu irrespective of the processing route, even though median values of ore demands varied between processing routes from ca. 35 (underground, conventional processing) to 200 kg ore/kg Cu (open pit, solvent-extraction, and electrowinning), as high specific ore demands are typically associated with less energy intensive extraction technologies and vice versa. Thus, only considering ore grade in LCIA methods without making any differentiation with regard to employed technology can produce misleading results.

Light detection and ranging (LiDAR) and multispectral studies of disturbed Lake Superior coastal environments

Due to its high spatial resolution and excellent water penetration, coastal light detection and ranging (LiDAR) coupled with multispectral imaging (MSS) has great promise for resolving shoreline features in the Great Lakes. Previous investigations in Lake Superior documented a metal‐rich “halo” around the Keweenaw Peninsula, related to past copper mining practices. Grand Traverse Bay on the Keweenaw Peninsula provides an excellent Great Lakes example of global mine discharges into coastal environments. For more than a century, waste rock migrating from shoreline tailings piles has moved along extensive stretches of coast, damming stream outlets, intercepting wetlands and recreational beaches, suppressing benthic invertebrate communities, and threatening critical fish breeding grounds. In the bay, the magnitude of the discarded wastes literally “reset the shoreline” and provided an intriguing field experiment in coastal erosion and spreading environmental effects. Employing a combination of historic aerial photography and LiDAR, we estimate the time course and mass of tailings eroded into the bay and the amount of copper that contributed to the metal‐rich halo. We also quantify underwater tailings spread across benthic substrates by using MSS imagery on spectral reflectance differences between tailings and natural sediment types, plus a depth‐correction algorithm (Lyzenga Method). We show that the coastal detail from LiDAR and MSS opens up numerous applications for ecological, ecosystem, and geological investigations.

Comparison of typical regulatory mechanisms for improving global mine safety and health

A comparative study on the typical regulatory mechanisms of the USA, South Africa and China. This paper makes a comparative analysis of the institutional and regulatory framework in mine safety and health among the three nations. The study highlights the positive role of the current US safety framework, which results in a mutually supportive triangle consisting in law enforcement, technology, and education/training. South Africa mine safety regulatory framework is based on a tripartite framework, state, employer, and employee. A new safety policy approach through multi-stakeholders has been proposed in China to continually improve their mine safety and health performance.

Canaries in a Global Coal Mine?

Moller, Anders P., Wolfgang Fiedler, and Peter Berthold. 2006. Birds and climate change. Elsevier, Burlington, Massachusetts. xvi + 251 p. $49.95, ISBN: 978-0-12-373614-7 (alk. paper).