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By R Dimitrakopoulos, I Minniakhmetov

Geostatistical simulation techniques are used to quantify uncertainty of spatial attributes of interest describing mineral deposits, petroleum reservoirs, hydrogeological horizons, environmental contaminants and so on. The majority of existing methods consider second-order spatial statistics and Gaussian processes, while the more advanced multiple point-based simulation approaches are algorithmic and do not consistently account for the high-order spatial relations in data. Recently, simulation techniques for complex and non-Gaussian spatially distributed variables have been developed, based on high-order spatial cumulants, and make no assumptions on data distribution or require data transformations. In this paper, the previous developments are extended and a new approach for the joint simulation of multiple correlated variables using high-order spatial statistics is proposed. The technique is based on a new algorithm for the decorrelation of correlated variables into factors, using the so-termed diagonal domination condition of high-order cumulants. The decorrelated factors are then simulated using high-order simulation and back-transformed into the initial correlated variables. The decorrelation using diagonal domination of high-order statistics is tested with a data set from a multielement iron ore deposit, and then a fully known two-dimensional data set with two correlated variables is used to demonstrate the practical intricacies of the proposed method.CITATION:Minniakhmetov, I and Dimitrakopoulos, R, 2014. Joint simulation of correlated variables using high-order spatial statistics for orebody modelling, in Proceedings Orebody Modelling and Strategic Mine Planning Symposium 2014 , pp 53–60 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 24, 2014

By S. B. Bhagwat

The United States has abundant coal resources that could last at least another century. and probably longer at present consumption rates. Geographically, the coal resources are distributed over the entire nation including Alaska, although there are no coal deposits in the highly populated areas on the two coasts. This allows free access to the coal, but makes transportation more expensive. Not all coals can be utilized equally because they differ vastly in quality. The sulfur content of coals, considered as the most detrimental acid rain-causing element, varies from as low as 0.3 percent in some areas of the western U.S. to 5 percent or more in parts of the Midwest. The chlorine content, which causes corrosion of plant hardware, also varies regionally. The 1990 amendments of the Clean Air Act of 1963 (CAA) require that emissions of sulfur be restricted and rolled back in two stages by the year 2000. There have been a number of reports expressing concern about the future of the industry in the states where high sulfur coal is produced. The remedies devised by the federal government and many coal-producing states in the past to "se-cure" the future of the regional coal industries have focused on the physical task of removing sulfur rather than the economic challenge of doing so at a cost that will enable high-sulfur coals to survive and compete. The past remedies, generally, were not specific enough to account for the characteristics of regional coal deposits and did not look at the coal market as an integrated national and international entity. The State of Illinois has, in recent years, taken a more comprehensive approach to the solution of the problem.

Jan 1, 1992

By Harold J. Barnett

In January 1948 , the Secretary of the Interior directed that a study be made of energy resources and requirements that would provide a basis for continuing appraisal of the adequacy of the Department's programs in the energy field . That this instruction was timely has been demonstrated by the increasing interest being evidenced by Congress , industry , labor , and the public in the future of the energy segment of our national economy . Several studies of individual energy sectors have appeared . Various legislative proposals have been made in Congress for obtaining more information on this subject . Substantial interest in energy projections is not , of course , a recent innovation . Energy availability and consumption are strategic factors in peacetime prosperity and growth and in our national defense as well . The past generation's literature of earnest public discussion and of legislative consideration of matters involving energy projections is very extensive . This is an exploratory study produced in the Program Staff of the Office of the Secretary of the Interior in the first half of 1949 and revised recently to take account of certain of the preliminary energy data from the 1947 Census of Manufactures and critical comments . It is offered at this time solely as a technical contribution in economic research technique . As the Bureau of Mines has recently undertaken to revise this preliminary study , critical and other comments are invited .

Oct 1, 1950

By AIME AIME

LOCAL COMMITTEES. EXECUTIVE.-W. A. Lathrop, Chairman; R. V. Norris, Secretary; S. D. Warriner, Treasurer; Irving A.. Stearns, W. J. Richards, H. S. Drinker, C. D. Simpson. GENERAL RECEPTION.-Irving A. Stearns, Chairman. Archibald, James, Jr., Pottsville. Lawall, E. H., Wilkes-Barre. Ashley, H. H., Wilkes-Barre. Lentz, W. 0., Mauch Chunk. Ayres, WV. S., Hazleton. Lewis, Albert, Bear Creek. Beard, J. T., Scranton. Loomis, W. H., Jeddo. Bridgman, J. C., Wilkes-Barre. Markle, Alvan, Hazleton. Bunting, Douglas, Wilkes-Barre. Markle, John, Jeddo. Chase, F. M., Wilkes-Barre. Neale, J. B., Minersville. Coroner, Eli T., Scranton. Norris, R. V., Wilkes-Barre. Cote, E. B., Jr., Drifton. Oliver, Paul A., Oliver's Mills. Davies, W. H., Hazleton. Owens, W. D., Pittston. Davis, H. G., Dorranceton. Pardee, 1. P., Hazleton. Dodge, W. F., Wilkes-Barre. Quin, R. A., Wilkes-Barre.

Jul 1, 1911

By J. S. Young

During 1975, the Reclasource Corporation constructed and commissioned a plant for the recovery of mill scale, coke breeze, blast furnace dust, blast furnace sludge and basic oxygen furnace dust at the site of Crucible Alloy Division, Midland, Pennsylvania. The Reclaform Process was employed as the criteria for plant design. This Process takes the solid in-plant fines as listed above, commonly found in integrated steel mills, sizes and forms them through the use of a carbonaceous binder briquetting system and cures the binder through a final heat-treating step. 15,000 tons of Reclaform briquets have been tested in the Crucible blast furnace in several campaigns structured to assess material handling properties, burden feasibility and finally culminating in an iron and carbon assessment campaign. Data are presented from the records of the blast furnace operation and conclusions are drawn that both iron and carbon utilization have been demonstrated.

Jan 1, 1977

By William D. Mayercheck

The U.S. Bureau of Mines is conducting research aimed at providing technology for a low-cost, high-recovery, environmentally acceptable mining system to recover the vast thin-seam coal reserves existing in the mountainous areas of the Appalachian region in the Eastern United States. As part of this research, the Bureau is evaluating new techniques to address these coal resources. This report summarizes the results of a worldwide technical search on thin-seam coal mining, the formulation of various methodologies for mining mountaintop thin seams, and the implementation and status of a physical model test program to validate and further develop the most promising concept-the "roof-fall-tolerant" mining system.

Jan 1, 1990

By S Coward, J Vann, R Wolff, S Jackson, S Moayer, A Bye

Uncertainty about the future and orebody should significantly impact evaluation of mining projects. Scenario planning, widely used in other industries, for example in the petroleum industry, can provide organisations with an opportunity to explore the consequences of uncertainty on their future plans. By developing plausible scenarios, scenario planning assists decision makers by allowing them to make systematic and possibly effective decisions for the future. This paper reviews existing mine project evaluation in the context of a new framework called scenario-based project evaluation (SBPE) (Vann et al , 2012) that addresses many shortcomings of existing approaches. SBPE uses conditional simulations (CS) models as inputs which are evaluated against future alternative project pathways (æalternativesÆ). These alternatives are evaluated using multiple plausible images of the deposit (CS realisations) which capture realistic variability and as an ensemble, map uncertainty of various orebody attributes at fine scale. The alternatives can involve different mining, stockpiling, blending and processing strategies. The ultimate output is a (stochastic) set of cash flows for each alternative from which financial measures, such as NPV, can be derived. Alternatives can then be explored in the presence of against external scenarios such as changes in prices, costs, and taxation. The obvious problem with such data rich results is knowing which scenarios or group of scenarios are optimal.An innovative approach to robust stochastic optimisation (RSO) suited to the SBPE framework is presented here for the first time. This approach to RSO aims to deal with the large number of alternatives generated from SPBE. The goal of applying the RSO approach to SBPE is to identify robust strategic alternatives (project configurations) which have the flexibility to deal with variability and uncertainty of geological and processing inputs such as density, grade and process performance. By applying the proposed RSO method, it is possible to deal with uncertainty and identify the best project configuration in the face of a large number of envisaged scenarios. A case study is provided, in which we have tested the application of the proposed method and compared the result with conventional methods. An important conclusion from this research is that selecting the value of the penalty coefficients in the RSO approach proposed is (as is all optimisation) an exercise of trade-offs; a higher net present value (NPV) is generally associated with a higher risk and a lower risk is associated with a lower NPV. Indeed, this is a strong argument for considering the RSO approach outlined here over more conventional approaches.CITATION:Moayer, S, Vann, J, Coward, S, Jackson, S, Bye, A and Wolff, R, 2012. An innovative approach to robust optimisation for scenario-based mineral project evaluation, in Proceedings Project Evaluation 2012 , pp 141-148 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 24, 2012

By Douglas H. Brown

Cadmium and other 'minor' metals in Canada tend to remain inconspicuous given the prominence of the country's massive production of other minerals. This same reality is reflected in the accuracy and deficiency of quantitative data concerning the sources of supply and demand for these metals. It is the intent of this paper to identify the nature of some of these difficulties and to reconstruct a more accurate description of Canada's production and consumption of cadmium, based on the results of recent surveys undertaken by the Mineral Policy Sector of Energy, Mines and Resources Canada and Noranda Sales Corporation Ltd.

Jan 1, 1978

By Joram M. Amir

During recent years, the integrity testing of piles has made considerable progress. With the availability of portable and powerful computers, practically all integrity testing equipment is now digital. Using sophisticated software for data acquisition and analysis, today's testing systems can provide owners with important information regarding both the length and integrity of piles and drilled shafts. This sophistication carries a price: Very few clients, including experienced engineers, do understand the strange-looking graphs adorning the reports they get. In fact, most of them will never ask, some because they are too busy to care and others because they are ashamed to show their ignorance. This situation is well exploited by a few shrewd operators of test equipment. Facing strong competition and falling revenues, they simplify their task and cut their expenses by the following means: 1. Using old equipment until it falls apart, and then some, 2. Hiring under-qualified personnel, 3. Staying on site as little as possible, 4. Eliminating the analysis and evaluation stage altogether, 5. Confirming as-made lengths and reporting no defects.

Jan 1, 1999

By Qinghua Gu, BUQING XUE, XUEXIAN LI, JIANGSHAN SONG, Qian Wang

Updating the openpit vehicle transportation network has the problem of being time consuming and low precision. To address this problem, a high-precision road network model construction method for unmanned vehicles in openpit mines is proposed. This method can be divided into two steps. In the first step, an improved deep learning image processing model named DeepLabv3+C (DeepLabv3+Concat) is presented, and the road information extracted by the DeepLabv3+C network is used to construct a three-dimensional model of the openpit mine road network. In the second step, aiming at the time-consuming problem of unmanned vehicles meeting in openpit mines, a vehicle meeting strategy is proposed. This strategy is used to guide the navigation of unmanned vehicles in openpit mines. At the end of the study, vehicle running simulation was carried out on the road network model using Unity, a 3D visualization simulation software. The high-precision unmanned road network model of openpit mines studied in this work can further promote the construction and development of smart mines by acting as a high-precision map for unmanned vehicles.

By S. Benedict Levin

The Big mine has been a source of mica and high-grade felspar from separate zones in the same pegmatite dike since 1914. In 1943 it became the outstanding producer of strategic mica in New England. The urgent need for sheet mica led to core-drilling by the Bureau of Mines from February to May 1914. Nine diamond-drill hob's aggregating 1,474 feet in length were drilled by the Bureau of Mines with the objective of developing extensions of the known mica shoots. The use of large-diameter bits made it feasible to obtain reasonably reliable results in diamond-drilling this type of deposit.

Jan 1, 1949

By Jacob Bouke, Jason Janisch, Erik Vlot

The use of conventional tailings deposition methods has been the standard for decades. With the need to reduce the impact of mining, alternative methods are considered when expanding or upgrading tailings handling systems. Converting an existing tailings management system to a more sustainable deposition method during the operation of a mine may incur considerable operational and financial risk, and when assessed more traditionally, does not provide significant advantages. As a result, most mines choose to continue their current technology and add an additional pumping stage or pumpstation to their tailings line in case of a pipeline extension or Tailings Storage Facility (TSF) expansion. This also often involves raising embankments. Changing pumping technology is traditionally assessed by comparing the energy efficiency of current and prospective pumping technology. Despite a reduction in absorbed power, this traditional assessment does not include possible savings in water and the carbon footprint. With the consideration of all these three aspects, alternative pump technologies, such as Positive Displacement (PD) technology, become more economically feasible, providing increased sustainability and enable a site to future-proof their operations. Project feasibility may be affected by the high capital investment required for PD pumps. The benefit of applying PD pumping technology could be enhanced by reducing the volumetric throughput of the pipeline by dewatering the tailings to 65% solids concentration by weight. It was found that despite increasing capital expenditure, the improved reclamation of water will have a positive effect on the direct and indirect cost of fresh water intake to mine operations. This paper seeks to illustrate that in many applications the long-term benefits of investing in sustainable tailings management are optimized when more efficient PD pumping technology is combined with tailings dewatering when upgrading or expanding the tailings handling system.

Feb 1, 2024

The latest resource estimate for the Caspiche gold/silver/copper project in the Maricunga region of Chile was released by gold explorer Exeter Resource Corp. The resource is low grade, but bulk minable and drilling to date has shown a NI 43-101 compliant inferred resource of 1,117 Mt (1.23 billion st) grading 0.55 g/t (0.016 oz/st) gold, 3.81 g/t (0.111 oz/st) silver and 0.22 percent copper. Exeter said these findings make the in situ metals amounts of 609 t (19.6 million oz) of gold, 4.4 kt (137 million oz) of silver and 4.84 billion lbs of copper, which the company relates as 33.7 million gold equivalent ounces using assumed metal prices of $23.33/g ($800/oz) for gold, 35 cents/g ($12/oz) for silver and $2/lb for copper. The deposit is almost midway between Barrick?s Cerro Casale gold deposit and Kinross? Refugio Mine. In a statement Exeter chairman Yale Simpson said ?This updated resource estimate places Caspiche firmly among the world?s largest gold-copper discoveries in recent years and clearly supports our decision to aggressively drill the property, despite the global economic decline. ?We expect that the very substantial copper and silver credits will be extremely important, and will markedly impact the potential viability of Caspiche. Specifically, using metal prices of US$2/lb copper, $23.33/g ($800/oz) gold and 35 cents/g ($12/oz) silver, the 4.84 billion lbs of copper and 4.2 kt (137 million oz) of silver are equivalent to 376 kt and 62 t (12.1 and 2 million oz) of gold, respectively. ?Our recent drilling has defined what appears to be a coherent higher grade central zone associated with a definable early stage diorite intrusion. We expect this zone will be important in developing various mining and economic models for the project,? Simpson said. Exeter is still drilling the deposit to expand the re-source estimate further to the southeast and at depth and to upgrade the higher grade central zone to the indicated category. Simpson said, ?Exeter intends to enhance the value of Caspiche by continuing to de-risk the project through ongoing exploration, metallurgy, engineering, water and environmental studies. These studies will continue through the next 12 months and will lead to a conceptual development study. A timeline for the release of that study is being formulated. The project budget for the next 12 months is C$14 million.? Mineweb reported that Caspiche is likely too big of a deposit and at too high of altitude for Exeter to handle alone. Exeter will be looking to other majors, or perhaps the Chinese, to help develop this huge orebody. But, in the meantime, it also has its high grade Cerro Moro deposit in Argentina, which could be brought to production relatively quickly and at relatively low cost.

Jan 1, 2009

By Jr. Winters

The United States continues to be the largest producer and consumer of copper in the world. Table 1 on the following page shows several production statistics for 1974, the most recent year which the non-communist world copper industry might consider a good year, and for 1976 and 1977. In 1974 an estimated 24 percent of the non-communist world's newly mined copper was mined in the United States, and. 87 to 89 percent of that was from the western porphyry coppers. In 1976 U. S. new mine production was down to 22 percent of the non-communist world's newly mined copper, and the percentage of U. S. new mine production supplied by the porphyry coppers had risen to 89 to 91 percent. In 1977 the statistics remained the same as in 1976. U. S. porphyry copper production represented about 65 percent of U. S. refined copper consumption in 1974, rose to 75 percent in 1976, and dropped back to 61 percent in 1977 as imports of foreign copper into the United States began to swell.

Jan 1, 1978

By William Gleason

The Society for Mining Metallurgy and Exploration (SME) has a long and proud history of being the world?s leading resource for the dissemination for technical information regarding the fields of mining and mineral extraction and processing. That reputation was met, and maybe even exceeded, with the programming for the Society?s 2014 Annual Meeting in Salt Lake City, UT Feb. 23-26. The meeting drew more than 6,700 attendees to the three-day conference that featured more than 90 technical sessions with 670 presentations. These sessions covered the breadth of the mining and minerals industry, but it was the so-called ?softer issues? that were discussed in the keynote session that kicked off the meeting. The keynote session, ?Community Engagement: Building Partnerships for Mining,? brought together some of the leading voices from the mining industry, as well as some of the top voices from nongovernmental organizations (NGOs) that work in the mining sector. The common ground between the panelists was their dedication to working to ensure a social, economic and environmental balance in the development of mines. ?We wanted to bring these NGOs in to begin a dialogue to see how we can work together,? said SME President Jessica Kogel. ?This is a space that SME has not typically operated in, but one in which SME can bring a technical, scientific voice to the discussion. SME wants to play a leadership role in creating partnerships between the technical, social and economic areas that are crucial to the success of any mining project.? In today?s environment, finding mineral deposits and extracting the minerals in an economically viable manner is just one piece of an increasingly complex puzzle. Earning and maintaining a social license to operate requires careful consideration of local and global impacts. The industry often comes under intense scrutiny when a new project is proposed and, therefore, it must strive to meet the highest ethical and environmental standards. Success requires cooperation and collaboration between the industry, community and NGOs.

By C. D. Rowe, H. S. Mitri, J. Malki, I. Vennes

Ore extraction at great depths creates high stresses around mine openings, which can result in violent rock failure in one of various forms of strainburst. This is especially true with strong and brittle rocks, which can store a large amount of strain energy that is suddenly released at failure. The strength and brittleness of rocks have been extensively investigated in the past. The most widely accepted method for the determination of rock burstability is the strain energy storage index obtained from a non-destructive uniaxial load–unload test. However, the results of this method are not always conclusive, showing less repeatability when the target test load is changed. This study concerns itself with the introduction of microscopic analysis as a tool to help validate the strain energy index results when burstability cannot be warranted based on mechanical property tests alone. In this study, two types of rocks, namely, basaltic komatiite (BK) and felsic norite (FNOR) obtained from Canadian underground mines are examined. The selection is based on the premise that felsic norite is known to be burstable from the mine experience, whereas basaltic komatiite is not necessarily burstable. A total of 60 mechanical properties tests were conducted including uniaxial compressive strength, Brazilian tensile strength, and load-unload tests. Laboratory tests on FNOR consistently exhibit high burstability; however, the results for the BK tests are not conclusive. To seek explanations for the mechanical rock behavior, 18 thin sections were examined with optical microscopy and image analysis. The findings show the tested BK specimens are dominated by alteration products, and all primary igneous minerals are lost. There is minor quartz, garnet, carbonate minerals, talc, and serpentine, which give the rock its ductile properties. The FNOR specimens are found to be relatively fresh and supported by a strong network of plagioclase with minor pyroxene, biotite, and secondary micas, explaining the higher stiffness. This study demonstrates how optical microscopy can complement mechanical property tests to evaluate burstability of rocks.

May 4, 2025

By Mario A. Terceros Herrera, Mario Terceros Arce, Antonio Marinucci

A Smart Cell is a closed-type tip post-grouting device that is attached to the bottom of the steel reinforcement cage of a drilled shaft and is used to enhance performance and to reduce uncertainty thereof. Control of the grout is maintained within the device during injection and a uniform stress is imparted across entire base area simultaneously, inducing a pre-mobilization load into the shaft as well as the soil. This paper describes the construction and tip post-grouting of drilled shafts from two bridge projects in the Santa Cruz, Bolivia region along the Paraí River. During the grouting process at each project site, there were noticeable differences in the grouting pressures achieved and responses observed, even within short distances between shafts. For this project, the greater benefit of using the Smart Cells was the reduction of risk and uncertainty of performance due to the highly variable soil conditions. Ultimately, since the response of each shaft was observed during grouting and because a “minimum” value of shaft resistance (i.e., pre-mobilization of load) was measured, there is a greater reliability with the anticipated performance of the shafts when axial loading is eventually applied.

By D. Harrington

The record of fatalities from mine explosions during the past 2 fiscal years has been anything but encouraging; more men were killed by explosions (379) than were killed from the ante cause during to' preceding 6 years combined (368). The reason for the large increase in the number of explosion fatalities during the past 2 years as compared with the previous 6 years is not entirely clear. In some instances, there has been laxity in the enforcement of State mining laws; in others, both workers and operating officials is have failed to observe recognized precautionary measures to prevent explosions. In many of the explosions that lave occurred within the asst few years in mechanized mines it has been evident that speed of operation and a demand for maximum tonnage at minimum cost resulted in neglect of ordinary safety measures.

Jan 1, 1942

By Sidney Katell

This study estimates capital investment, operating costs, and selling prices for four underground bituminous mines producing coal with annual production ranging from 1.06 to 4.99 million tons. It is assumed that the mines have a 20-year life. Wages and union welfare payments are considered as of December 6, 1974, under the Bituminous Wage Agreement of 1974, and costs for material and equipment are based on 1975 indexes. Initial capital investment ranges from $23,629,500 for the 1; 06- million-ton-per-year (MM tpy) mine to $79,907,500 for the 4.99-MM-tpy mine. Total capital investment ranges from $35,336,500 to $1 18,863,500 for the same mines. Corresponding selling prices for the coal range from $13.57 to $11.36 per ton, assuming a 15-percent discounted cash flow rate of return after Federal income taxes.

Jan 1, 1975

By I. Barin

The thermodynamics of cyclone smelting of sulphidic copper ores is described using as example the production of copper matte with 75 wt % Cu. Equilibrium calcualtions and material and energy balances show that an increase in process temperature from 1600 K to 1900 K results in the extensive transfer of minor elements such as As, Sb, Bi, Pb, Zn,.... to the gas phase. A pilot plant for carrying out the cyclone smelting process is described. Calculations of material and heat transfer for the reaction of ZnS show that the smelting reactions of sulphides in the cyclone take place very rapidly at high temperatures. The dissociation of the sulphides with subsequent oxidation reactions in the gas phase plays an important part in. the process and is mainly controlled by heat transfer.

Jan 1, 1983