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By S. Henley

Paper presented at a meeting on: Artificial intelligence in the minerals sector, held in Nottingham, UK, 20 April 1993 (original title: The database: a pre-requisite for large-scale use of AI in mining). Artificial intelligence is a term which has been widely applied to different techniques including rule-based systems using inductive and deductive logic algorithms, neural networks, learning systems and genetic algorithms. In principle it should be applied to adaptive statistical techniques. Some of these applications have been coded in languages which are specifically suited to the novel requirements of AI but are not easy to integrate with more traditional computing methods. Efforts have been made to bridge the gaps, particularly with database management systems and such efforts at integration should provide the key to future success in the application of AI. A field which has been termed "knowledge engineering" cannot be credible as such if it fails to provide easy access to raw materials of "knowledge" i.e. the data residing in databases. In the mining industry there are a number of significant areas in which AI could usefully be applied throughout the industry, but its advance is slow because of the lack or inefficiency of such database links. Current development of object-oriented database systems for geology and mining holds out hope for such integration in the foreseeable future

Apr 1, 1994

By Donald E. Redmon

This Bureau of Mines report examines the injury experience in the quarrying industry For the years 1966-67. Twenty-eight tables for each year are presented in which disabling work injuries are summarized by department, source of injury, extent or disability, part of body injured, and nature of injury. Correlative information on employment, worktime, and operating activity is also presented.

Jan 1, 1973

By T. Tholana

South Africa hosts some of the world?s largest known resources and reserves of minerals that are strategically important to the global economy. The country?s mining industry contributes significantly to the national economy in terms of gross domestic product, export earnings, corporate tax receipts, remuneration earnings, and employment. Platinum, gold, and coal are significant minerals because they make the largest individual contributions to these economic indicators. Several factors impact the cash cost performance of operations that mine these minerals, thus affecting the future sustainability of these operations, which are generally ?price-takers?. It is therefore important that the cash cost performance of operations for these key minerals is analysed. Commercially available industry cost curves can be used for such analysis. However, some companies may not be able to afford to purchase these curves. This paper presents a simple Microsoft Excel® algorithm for constructing the curves. It also demonstrates how the constructed industry curves were used to analyse the cash cost performance of South African mining operations for the three selected minerals for the period 2007 to 2011, which included the 2008 global financial crisis. The analysis revealed that the operations were affected by several global and local factors during the review period. The work reported in this paper is part of an MSc research study at the University of the Witwatersrand. Keywords cost curve algorithm, economies of scale, cash cost performance

Jun 1, 2013

By Lucas Lopes da Costa

In this work, a natural foam extracted from the Amazon buriti palm tree is investigated as possible substitute for synthetic foams. The basic physical and mechanical properties of this biofoam were evaluated. Its sponge-like structure was characterized by the amount of pores and morphological aspects. It was found that the buriti biofoam displays a very low density of the order of 0.1 g/cm3 with a relatively good compressive strength. This would be suitable for several engineering applications and as a new material with the potential for replacing currently applied synthetic polymeric foams.

Jan 1, 2010

By Carlos A. Prato, Federico Pinto

"ABSTRACTThe design of drilled shafts often incorporates large factors of safety, for which settlements under service loads are highly influenced by the initial elastic stiffness. In the case of groups of drilled shafts with typical spacing, the elastic shaft-soil-shaft interaction dominates the behavior even for loads close to the bearing capacity, for which the initial stiffness is a key parameter in the design. This paper describes typical trends in results obtained by means of different approaches currently available in the literature for the evaluation of the initial stiffness of a single shaft. An experimental technique that provides a rapid and inexpensive means for the evaluation of the initial stiffness is described, and the results obtained for typical cases are compared with analytical predictions.IntroductionThe behavior of drilled shafts under axial loads is generally governed by the initial stiffness, as the factors of safety considered in design are often large, due to a superposition of conservative assumptions on soil properties and expected loads. In the case of shaft groups, the initial elastic stiffness plays a major role together with the elastic group effects, as nonlinearities tend to localize around the shafts and have a lesser effect than elastic deformations on adjacent elements (e.g., Leung et al., 2010). An accurate characterization of the initial stiffness is thus warranted for the analysis of drilled shafts and shaft groups under service loads.Initial stiffness of shafts may be estimated on the basis of soil stiffness and structural properties of the element by means of numerical methods (e.g., Pinto and Prato, 2006), as well as analytical methods (e.g., Randolph and Wroth, 1978). The soil stiffness may be determined by means of geophysical tests (e.g., Spectral Analysis of Surface Waves, SASW, Stokoe et al., 1994), or correlations with Standar Penetration Test (SPT) blowcounts or Cone Penetration Test (CPT) resistances (e.g., Sabatini et al., 2002).The initial stiffness may also be measured on drilled shafts by means of load tests. Static load tests (SLT), however, have some limitations on measuring small deflections, for which the initial stiffness is often extrapolated by means of large strain measurements (e.g., Chin, 1970), where the SLT measurements are more accurate."

Jan 1, 2014

By K. Delbeke

Within the framework of the EU Existing Substance (93/793/EEC) and REACH regulations EC/1907/2006), the copper industry initiated in 2000 a comprehensive Voluntary Risk Assessment of copper and several copper compounds. The Italian Government's Istituto Superiore di Sanità, reviewed the process and reports on behalf of the European Commission. Copper exposure levels to man and the environment from production of copper anodes and cathodes, copper powders and copper chemicals as well as fabrication and use of semi-fabrication products and down stream user products were collected across Europe. Environmental and human health effects data were obtained from literature as well as novel research programs and used to deduct safe threshold

Jan 1, 2007

By James Westfield

Following is a brief resume of the Division's activities that have had a favorable effect on health, safety, and the reduction of injuries at coal mines: 1. The Federal Mine Safety Code for Bituminous Coal and Lignite Mines of the United States was issued originally by the Director of the Bureau of Mines on July 24, 1946, after consulting with management and labor representatives of the coal-mining industry. The code has been used by Federal coal-mine inspectors while inspecting bituminous-coal and lignite mines as a basis for determining the existence of unhealthful and unsafe conditions and practices in these mines. A revised code was issued by the Secretary of the Interior on October 8, 1953, after further consultations with representatives of management and mine workers and was incorporated by reference in the 1952 and subsequent bituminous-coal wage agreements. The agreement of May 29, 1946, between the Secretary of the Interior, acting as Coal Mines Administrator under authority of Executive Order 9728, and the United Mine Workers of America, covering bituminous-coal and lignite mines in Government possession, charged Federal coal-mine inspectors with the responsibility of making periodic investigations of the mines and reporting to the Coal Mines Administrator any violations of the Federal Mine Safety Code. Federal coal-mine inspectors also had temporary authority to close mines found to be imminently dangerous, but such authority under Executive Order 9728 was removed on June 30, 1947, when Government control of the mines was terminated.

Jan 1, 1961

By Charles L. Kusik

A study was conducted for the Bureau of Mines, U.S. Department of the Interior, to provide information which will lead to an increase in the recycling of mineral materials, in order to help conserve the Nation's mineral resources. Data were collected on energy requirements to recycle prompt industrial and obsolete scrap for nine metal commodities: Iron and steel, aluminum, copper, zinc, lead, stainless steel, titanium, tin, and nickel and nickel alloys. Major process routes for recycling were considered, starting from the first collection point through scrap preparation, transportation, smelting and/or refining to the molten metal, ingot, or other semi- finished form approximately equivalent to a primary metal of a similar composition. Available data for 1976 were collected on the amounts of each metal commodity recycled by major scrap categories. In addition, energy requirements were estimated for separating municipal solid wastes into four major categories: Refuse-derived fuel, and magnetic, aluminum, and glass cullet fractions. Finally, areas of research were identified to enhance recycling and/or increase the efficiency of energy use.

Jan 1, 1978

Core samples, which were collected by the author from the Busang prospect, East Kalimantan, reflect a progressive evolution of a large magmatic-related hydrothermal system that is comparable to that encountered in many similar systems elsewhere in the Pacific region. The initial, localized deposition of sheeted porphyry quartz-molybdenite veins took place at high temperatures and fluid salinities, and at relatively deep levels. This was followed by an extensive phase of phyllic (sericite-quartz-pyrite ¦ tourmaline-apatite) wallrock replacement and vein formation. Propylitic (epidote-chlorite-carbonate-quartz) alteration was formed marginal to the phyllic assemblages. These porphyry-related events were centred in the Southeast Zone, and are probably associated with the emplacement of a felsic intrusion at depth. This event contributed only trace gold to the system. The early stages of hydrothermal activity were followed by an episode of quartz (¦ adularia) û carbonate û base metal sulfide veining, which was accompanied by argillic (illitic-kaolin clay) wallrock alteration. This event was sulfide-rich in the Central Zone and carbonate-dominated in the Southeast Zone. Gold mineralisation was observed in Central Zone drillcore to be associated with both sulfide, as well as carbonate, deposition. A final stage of epithermal-style quartz ¦ stibnite û realgar veins are, in the Central Zone, locally gold-bearing. The latter two events are interpreted to be associated with the late-stage exsolution of metal-bearing brines from the felsic intrusion that formed the earlier porphyry quartz-molybdenite veins and widespread phyllic-propylitic alteration.

Jan 1, 2002

By Sibabrata Patnayak

A major problem during shovel excavation in oil sand mining is the variability of material diggability resulting in varying mechanical energy input, cycle time, energy consumption, wear, and stress loading of shovel dipper-andtooth assembly. This variability greatly influences the mining equipment performance. Different approaches such as empirical ground classification systems, analytical methods, and performance monitoring that are used to determine diggability of groundmass are reviewed. It is concluded that the existing empirical diggability classification systems are site specific and mostly based on rock and therefore, cannot be used for shovel excavation in oil sands. The O&K wedge test is a simple and useful index test for establishing correlations between cutting resistance and geotechnical properties of coal and other soft rock overburden material. But this test, when performed on small size unconfined oil sand samples, may not give reliable indication of diggability because of the boundary conditions on the specimens. Digging predictions made using analytical and laboratory digging models need to be verified with performance monitoring data to better understand the digging effort in oil sands.

Apr 1, 2005

Good morning and thanks for the chance to talk to you. It's really pleasing to see so many industry representatives here I want to spend a few minutes talking about issues relating to your industry. At the end of today I would like to leave you with three strong messages from government. The first is that this government supports environmentally responsible mining and the endeavours of the mining industry. The second is that explorers and developers are wanted and welcomed in New Zealand. And the last is that it is up to the industry to keep the public properly informed about how your industry and to constantly work on improving your public image. The mining industry is a high-tech industry which fits snugly with our concept of a growing knowledge-based economy. It has particular value for regional development, the gold mining industry alone provides more than 4,000 jobs û mostly outside of the main cities. The industrial minerals industry is twice as large as that. As well as those people directly employed by the industry there are greater downstream effects for the community. One example from the broader extraction industry of this is of the local pie shop down the road from one of Taranaki's petroleum industry locations. The shop sells over $4,000 worth of pies a week to workers in the industry. That's just one example of the positive benefits the industry brings to its local community and is the sort of real positive benefit you need to be telling people about  

Jan 1, 2000

By H. Kose

In this research, a model quarry with an annual production capacity of 1 000 000 tonnes has been studied for both pit and hillside quarry cases with constant overall slope angle and variable bench slope angle, considering road grades of 8 per cent and 10 per cent. First, technical requirements have been determined and then the effect of production parameters, such as hole diameter, type of quarrying (pit or hillside) and road grade, on the cost has been investigated to determine bench height. Based on the results, it has been concluded that hole diameter has to be kept large in both pit and hillside quarrying to reduce drilling unit costs. In addition, in order to take advantage of gravity and reduce transportation cost, it has been suggested that bench height and road grade have to be kept high and low respectively in the case of hillside quarrying (downhill transportation) while, in the case of pit quarrying (uphill transportation), bench height and road grade have to be kept low and high respectively, in order to transport the blasted material to a lower height and distance, to save energy, thus decreasing the transport cost. Keywords: Quarry, pit, hillside, road grade, bench height

Jan 1, 2005

By F. S. Kendorski

This report presents the results of a search for viable-self-drilling roof bolt concepts, detailed development, design, and manufacture of such bolts that drill their own holes, and testing in the laboratory and in the field in two different coal mines of three self-drilling roof bolts. Three new types of bolts were designed and tested, which drill their own holes and then anchor in continuous operation. These were a spring-actuated mechanical expansion shell, a slot and wedge, and a self-contained resin anchor bolt. Such bolts when fully developed for mine use would allow safer and remote installation of ground support and increase productivity. Recommendations are given for further work to improve drilling and anchorage performance.

Jan 1, 1979

By Charles E. Whieldon

Data on the oil fields in Mahoning Columbiana, Carroll, Jefferson, and Harrison Counties, Ohio, were collected from scattered sources and com- piled to make the information readily available to operators who may be interested in conducting secondary-recovery operations in the area. General geology, oil production, oil-productive acreage, core data, reservoir calculations by townships, and miscellaneous data and reference material are presented.

Jan 1, 1965

By Cassandra A. Wetzel

Rock socketed mini-piles are a desirable foundation alternative when design capacity is more than 40 tons and there is limited access. In this case history mini-piles were designed to support between 75 and 200 kips at 12 locations adjacent to a perimeter wall, a party wall and at cast iron column piers. Limited geotechnical information, low overhead clearance, and active building population tested the creativity of the team to get the piles installed. The key geotechnical concern during installation of the mini-piles was the presence of a glacial till layer above the bedrock surface that restricted the seating of the casing into bedrock with a track mounted drill rig. Soil loss during the advancement of the rock socket using an air hammer was excessive and increased the risk of subsidence. Over a three week period the engineer worked with the contractor to modify the design, means, methods, and materials to install piles with adequate load capacity. This paper will present the changes in design and construction methods that were required.

By P. H. Morris

The exponential delta profile equation matches the profiles of a wide range of coal and metalliferous subaerial tailings deltas well, but the original model implies unrepresentatively low solids concentrations. A revision, based on analysis of the governing equations of mobile bed flows with high concentration values, has shown that for exponential delta profiles to form there must be quasi-steady, slowly varying flow and slow deposition as well as tailings with a log-uniform sorting-parameter distribution. Deposition on tailings deltas is slow and the flow in many natural streams and, by analogy, tailings deltas is quasi-steady and slowly varying; the assumption of such flow is justified by the strong congruence of the revised model and the available data. The predictions of the theoretical model are essentially unchanged but concentration and flow Froude number are now not explicitly limited

Jun 19, 1905

By W. S. Fyfe, G. Southam, T. J. Beveridge

Bacterial populations play an active role in mineral weathering in subsurface and near-surface environments e.g., supergene enrichment of Cu at Morenci, AZ. An invitro bacterial biofilm model was used to examine the interaction between Sporosarcina ureae and ionic gold(which is toxic) or amino acid-gold complexes in gold mobility. The immobilization of ionic gold was between80-90% for 1 week but as the available, cellular reactive sites became saturated immobilization decreased to 14%within 2 weeks. In the asparagine-gold system, gold immobilization occurred at a high rate (80-90%)throughout the experiment with limited toxicity towards Sporosarcina ureae.

Jan 1, 1999

By S. Kelebek

DETA exhibits a highly selective depressant action on pyrrhotite without adversely affecting the collectorless flotability of pentlandite and chalcopyrite in nickel-copper ores of the Sudbury region. A simplified Eh-pH diagram has been constructed to illustrate the extended stability of elemental sulphur and to explain the collectorless flotation of pentlandite and chalcopyrite. Cu and Ni ions, which are known to exist on the surface of pyrrhotite, promote the flotation of this mineral whether a collector is present or not. Thermodynamic calculations indicate that the action of DETA involves the sequestration of Cu and Ni ions from surfaces under a wide range of redox conditions; analysis of flotation test filtrate indicates as much as a 20-fold increase in the concentration of Ni and Cu ions. It appears that DETA may enhance the self-hydrophobicity of chalcopyrite and pentlandite by exposing more of the sulphur-rich surface sites for bubble contact in flotation. There are various possible explanations for its depression of pyrrhotite

Jun 18, 1905

By S McKinley, S Juras, E Uludag

More and more, today’s mining geologists are asked to identify and create 3D value domains for multidisciplinary usage: grade definition, geometallurgical performance and geotechnical characteristics, to name a few. Often, that domain shape is the result of an assumed or conjectured value as a surrogate to a set of conditions (eg kaolinite-rich, sericite alteration). Would it not be instead better to create the respective domain through identification of a consistent quantifiable geologically-based pattern as its basis?Critical to the identification of patterns is the transformation of 3D point data into a model by a method that uses few, if any, preselected thresholds. Too often we complicate the reviews of the modelled data by prejudging the value range of interest. And when we do revert to 2D views (ie sections and plans), we tend to only examine numbers or line traces. These hinder and obscure identification of geological patterns particularly in deposits of complex geology. Instead, these data should be looked at with minimal prejudgment and interrogated in 2D space by one of the best and most eye-catching display types: filled contour plots.Here we present two different processes that transform data with minimal preselection into formats that allow for pattern recognition by filled contour plots. These are: probability assisted constrained kriging (PACK) and multiple interval interpolant formation (Aranz Geo’s Leapfrog® software). The former creates a 3D model of probabilities on a threshold value; the latter creates numerous (=10), regularly-binned 3D interval interpolants. The results of each method are examined as filled contours over numerous sections or plans. Any distinct patterns are quickly discerned thereby readily identifying the best value to base the creation of a domain. These processes therefore provide a way to marry recent advances in software tools with what is supposed a geologist’s core skill: pattern recognition.CITATION:Juras, S, McKinley, S and Uludag, E, 2017. Pattern recognition in transformed data – the search for domain shapes in mine geology data, in Proceedings Tenth International Mining Geology Conference 2017, pp 37–42 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 20, 2017

By H Bibby

Initial analysis of Long Offset Time Domain Electromagnetic (LOTEM) data has traditionally been made in terms of early and late time apparent resistivities. By using more than one grounded bipole as a source, a tensor analysis technique analogous to the method used to analyse DC resistivity multiple-source bipole-dipole surveying may be formulated. We define the æinstantaneous apparent resistivity tensorÆ as the tensor that relates the total electric field vectors at each instant to the steady state (DC) uniform half space current density vectors due to each source. Instantaneous apparent resistivity tensors calculated for a 3D resistivity model suggest that profiles of LOTEM measurements across simple 3D structures can be used to create an image that reproduces the main features of the subsurface resistivity. Where measurements are distributed over an area, maps of the tensor invariants or the tensor ellipses at different times can be made into a sequence of images which provide a way of ætime slicingÆ down through the target structure.

Jan 1, 1996