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By Pooley F. D

The coal measures of the South Wales coalfield contain at least 50 horizons at which coal seams are known, to occur. More than 300 samples of coal were collected from these coal measures and this paper outlines thefindings of an investigation of the pattern and distribution of 12 trace elements in South Wales coals. A comparison of trace element contents of the South Wales coals is made with trace element values found elsewhereand an attempt was made to establish the organic affinity of the elements in different seams and in the coalfield 'as a whole. An important function of such an analysis is to determine the order of abundance of trace elements and this was performed for individual seams and for the whole coalfield.The interrelationship of certain elements in some seams is also examined with a view to understanding the effectiveness of such an approach to seam correlation.Ranges of values are quoted together with the mean values of the various elements. Variations of elemental values within a seam section and over the coalfield as a whole are discussed.

Jan 1, 1977

By D R. Cohen

As one of the four basic sciences, the study of geology is intrinsically worthy as a means of increasing fundamental knowledge of the behaviour and evolution of the universe. Geological knowledge can also be translated into practical outcomes for society such as resource discovery and protection of the environment. Australia has a long tradition of providing very high quality geoscience programs to prepare graduates for a range of occupations. We are, however, reaching a nexus in the way universities should or can deliver engaging programs. This has been triggered by the rapid evolution of the digital world (the Internet of Things), new technologies, unprecedented access to information, better understanding of the processes by which we learn and adapt our thinking, growing complexity in the problems we must face or opportunities to grasp, and university funding models. Designing education programs for the next generation of geologists extends far beyond tinkering with syllabuses. We must develop skills sets that will allow graduates to work in rapidly changing landscapes, but in doing so may have to sacrifice content to build capability in our graduates. Whereas universities must respond to changing demands on graduates by ensuring degree programs contain an appropriate balance of material and high quality of delivery, industry and government must also fulfil their responsibilities to provide additional training programs for graduates to assist their rapid transition into independent professionals. This paper examines various educational issues being considered in developing the new Decadal Plan for the Earth Sciences, and reflects on directions that education is heading in many of our universities.CITATION:Cohen, D R, 2017. Educating the next generation of geologists, in Proceedings Tenth International Mining Geology Conference 2017, pp 3–10 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 20, 2017

By E Westthorp

Final mine sealing of BMA’s Crinum North mine, near Emerald, Queensland was undertaken in December 2015. Due to the benign atmospheric environment at Crinum North, the Queensland Mines Rescue Service (QMRS) Górniczy Agregat Gasniczy (GAG) unit was utilised to reduce oxygen levels throughout the underground atmosphere as part of the final sealing process.The GAG was utilised by way of a vertical borehole from the surface to seam to successfully reduce oxygen levels throughout the underground mine workings. Application of the GAG unit enabled the underground mine to be classified as stable and inert within days of the GAG operation, and subsequently cease gas monitoring at Crinum North. The data and information obtained from this activity provides valuable information to the underground coal mining industry on successful application of the GAG in realistic situations.This paper discusses the strategy used for sealing, the assisted inertisation and the results obtained from the application of the GAG unit. It discusses both the overall results and gives a detailed review of the gas monitoring data obtained via the tube bundle and real-time system, both during and following the use of the GAG unit.Gas monitoring results obtained and the strategy used are critical to share with the industry to obtain a better understanding of how the GAG unit works, and how it can be applied for emergency preparedness, emergency response or planned inertisation.CITATION:Westthorp, E, 2017. A review of the strategy and gas monitoring results obtained during the use of Queensland Mines Rescue Service GAG unit at Crinum North mine, in Proceedings Australian Mine Vent Conference 2017, pp 309–318 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 28, 2017

The Calypso geothermal field, mapped by the R V Sonne (cruise SO-135) in 1998, includes four main sites, the Northern Vent Area (centred on 37¦ 36.7'S, 177¦ 06.2'E, area 1.5 km2), Central Vent Area (37¦ 39.4'S, 177¦ 05.2'E, 1 km2), Southern Vent Area (37¦ 41.7'S, 177¦ 06.0'E, 1 km2) and Mercury Vent Area (37¦ 41.3'S, 177¦ 07.3 'E, 0.5 km2). Hydrothermal activity at the vent sites is controlled by minor, sub-parallel NE-trending normal faults. Gas bubble trails (C02) and shimmering hot water vent from fractures and joints between large blocks of silicified volcaniclastics and in depressions in the sediments at the base of these outcrops. Measured maximum vent temperatures are between 180¦C and 201¦C. Venting fluids are at, or just below, boiling for water depths of 200 m. Rock samples recovered by dredge from the sites include massive anhydrite, clay-altered pumiceous ash, silicified volcaniclastic sediments and volcaniclastic breccias cemented by sulphur. Clay-altered samples, dominated by randomly interstratified illite-smectite and accessory chlorite, indicate formation environments of 70¦C to 90 ¦C. Native sulphur is abundant throughout the samples. Fine-grained (<1 mm) disseminated pyrite and vein pyrite occurs in the clay-altered pumiceous volcaniclastics and argillites. In the Southern and Mercury Vent Areas, fine-grained orpiment, realgar and cinnabar have deposited in the sandy matrix of volcaniclastic breccias. Amongst the cinnabar, small (<2 mm) beads of native Hg formed on the surface of several rocks following their recovery. These samples also contained abundant light hydrocarbons, which coat the rocks with an oily sheen.

Jan 1, 1999

By A Webster, T Murphy

Block cave mining, in its broadest sense, has transitioned from an orebody/rock mass determined method of extraction, to a low-cost and high production mining method that may be applied to any large ore deposit. This inherently means that caving is now required in more complex rock mass conditions where assistive damage, through preconditioning, may be necessary. This requires comprehensive understanding of the geology, and its interwoven relationship with geotechnical parameters, and is made more challenging due to limited exposure in block cave mines. Limited mine development throughout the cave volume equates to a heavy reliance on drilling data in terms of observations, modelling of the mine geology, and collection of geotechnical data. This translates as increased uncertainty of geological and geotechnical models and has potential to impact significantly on the ability to make informed decisions in the design and operation of the cave mine.Modelling of cave propagation behaviour requires a complex, coupled system of draw of material, flow of material through the cave stocks, and propagation of the cave-back assisted by autogenic stress-related breakage of the rock mass, manifested as seismicity. The role of geological features in the process of cave propagation is not well understood and requires evaluation on a mine-specific basis, given the diversity of geological controls/settings of ore deposits and local variability of stress fields.Seismic monitoring systems can elucidate key geological features and domains, as heterogeneous seismogenic activity is observed ahead of the advancing cave-back. The observations made from analysis of seismic monitoring data may have potential to be used as a validation tool for numerical modelling of predicted cave behaviour in similar geological settings (eg next lift/panel).Understanding of the geological structure, at all scales, is critical to optimise the design and operating decisions made in a block cave operation. At present, intermediate-scale structure, anisotropy, mineralogy and model uncertainty may be neglected or under-represented despite their likely significant role in the mechanisms of cave propagation.Insights from an analysis of the Ridgeway Deeps block cave mine are discussed in this paper.CITATION:Murphy, T, Webster, A and Chitombo, G, 2016. Beyond rock mass characterisation – the impact of geology on block cave mining, in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016), pp 861–872 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016

Three main divisions of the Proterozoic are recognized in the North-West Division of Western Australia. These are referred to, in order of decreasing age, as the Mt. Bruce Supergroup, the Bresnahan Group, and theBangemall Group. The stratigraphy and distribution of each is described, their relative ages discussed, and a brief geological history of the whole area is presented.

Jan 1, 1966

By L O. Filippov, C H. Veloso de Melo, A Correa De Araujo

Froth flotation of iron ores is one of the most widely used methods to upgrade iron ore into high-grade concentrates. In recent years, reverse cationic flotation of iron ores has been specifically the subject of several studies. Since quartz is the most common gangue mineral in iron ores, understanding the behaviour of this mineral was the main target of the majority of such studies. However, with the depletion of mineral deposits considered rich and easy to process, it has become more common to find iron ores with complex gangue minerals, which are composed not only of quartz but by a variety of silicates. The mineralogical composition of the ore is an important factor for determining reagents and mineral processing parameters. The mineralogical suite of an ore also presents a paramount role for operational optimisation of any given flotation process. Some studies were performed with different types of amphiboles and other Fe-bearing silicates, for example, but the influence of the mineralogical nature of these silicates in reverse cationic flotation has not been fully explored and will be discussed here. Changes in the traditionally used reagent scheme for reverse cationic flotation, generally including alkaline pH values, polysaccharides as depressant (mainly starches) and primary ether amines and diamines, are expected when dealing with iron ores with complex silicate gangue composition.CITATION:Veloso de Melo, C H, Correa de Araujo, A and Filippov, L O, 2017. Reverse cationic flotation of iron ores with complex silicate gangue minerals, in Proceedings Iron Ore 2017, pp 241–244 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

By T Hirsi, M Weatherseed, T Ritasalo

Cooling tower design has not advanced significantly in the last decade. Recognising this, Outotec has developed an innovative horizontal outflow cooling tower with increased performance compared to conventional design cooling towers.Outotec® Cooling Towers operate today in applications such as spent electrolyte cooling in zinc plants and for gypsum removal before copper solvent extraction. In such applications the use of this latest design has enabled increased production and lower maintenance costs in the downstream operations.In actual operations, the cooling performance has been confirmed at start-up, and has demonstrated that the towers operate in accordance with the CFD modelling. In the last three years these towers have proven themselves in commercial operation to operate with high efficiency and availability.This case study will outline comparative data, collected over two years at a site where both Outotec and conventional cooling towers are operating. The data shows that Outotec cooling towers require less than half the maintenance time of conventional cooling towers, when adjusted to a total solution flow basis. A close partnership approach with the site has allowed continual development, ensuring high availability and high performance.Experience with previous cooling tower installations guided the development of maintenance philosophies and procedures; this resulted in a design where maintenance intensive components were accessible from the top of the cooling tower. This allows safe access to components and maintenance with little or no downtime.CITATION:Hirsi, T, Ritasalo, T and Weatherseed, M, 2015. Improving cooling tower performance with innovative horizontal outflow design, in Proceedings MetPlant 2015, pp 396–402 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 7, 2015

By A Asadov, D Nair

This paper discusses the determination of the percentage of crystalline material in a natural silica deposit which would be considered harmful to health (<10 ¦m). A sample of the natural silica material was recovered and split into a number of subsamples. Samples were sieved using a conventional dry sieve to remove material >300 ¦m before testing. Particle size analyses of the fine fraction showed 75 per cent of the material was below 10 ¦m. Initially XRD and XPS were run on the samples to determine the minerals and composition of the sample. The XRD revealed strong quartz peaks and smaller tridymite peaks with a high amorphous background. The XPS indicated traces of iron, titanium and carbon with dominant silicon and oxygen peaks. The structure of the sample was investigated using the SEM. It was apparent that there were a number of larger quartz crystals (>30 ¦m) with a mix of amorphous and crystalline in the finer fraction. It was also observed that amorphous material was attached to the surface of the crystals. In order to determine the percentage of crystalline quartz a known amount of quartz was added to the sample incrementally. On each addition an XRD scan was performed and the area under the peaks recorded. Back analysis of these peaks with an assumed percentage of crystalline material in the original sample gave a crystalline content of 30 per cent. The quantity at the respirable fraction was estimated to be 18.7 per cent.

Jan 1, 2003

The Golden Ridges Mine, one of the properties of New Guinea Goldfields Limited, is situated on the right bank of Nami Creek, not far from the township of Wau, in the Territory of New Guinea.The property is somewhat unique, in that the goldbearing ore-body occurs in the form of a flat seam-like deposit lying on a volcanic breccia, and covered with a mantle of overburden of decomposed porphyry. The overburden varies in thickness up to a maximum of about 65 ft.The ratio of overburden to ore is about 3 to 1. The practice developed is to strip the overburden by hydraulicking, and to mine the exposed ore under open-cut conditions, blasting to a vertical face, and using electrically operated scraper hoists for conveying the broken ore to the mill bins.The stripping of the overburden involves the boring of well-drill holes, blasting the holes and then hydraulicking the shattered material.

Jan 1, 1934

Water quality standards for some of the substances likely to be discharged to natural waters by the mining industry are discussed. After briefly examining how uses of water can be affected by discharges, standards for suspended solids and turbidity, pH, and toxic materials are considered. Heavy metals are examined in some detail because of recent public concern regarding their discharge. Caution is given in connection with their analysis at the very low concentrations required for management of natural waters. Finally, the issues of what constitutes a water right concentration compliance breach, and the appropriateness of biological monitoring as a condition on a water right are raised.

Jan 1, 1986

By M Bourke

Modern computers and software provide powerful tools for the geologist to construct reliable models of geological resources, and the mining engineer to produce accurate and workable mine plans. Over the years many people have developed a phobia of computers, especially for geological analysis, modelling and mine planning. This phobia is often caused by a lack of knowledge, poor training or a bad experience. The adoption however of computers for geological modelling and mine planning is now becoming mainstream. With the correct training, a good understanding of input data, and detailed knowledge of the required results, the phobia can safely be overcome to provide mining operations with increased productivity.

Jan 1, 1999

Three methods of gold analysis are briefly described highlighting some of the problems and advantages of each. The variation of results between samples and splits and due to method of preparation is illustrated. The mean per cent difference of the fire assay values from the means of sample split values for three cases is 15 per cent.Finally, a comparison of the aqua regia leach atomic absorption spectroscopy (AAS) and fire assay fusion AAS techniques is made.This shows that the mean precision, the ability to obtain the same value, of the methods at 98 per cent confidence is ± 30 per cent and ± 15 per cent respectively. The fire assay fusion AAS method is relatively more accurate than the aqua regia one.

Jan 1, 1984

By C G. Ryan, T P. Mernagh, S R. Hunns, R A. Both, R R. Large, J B. Gemmell

 The Hellyer and Mt. Chalmers deposits are mound-style volcanic-hosted massive sulphide (VHMS) deposits in Australia. Textural, petrographic and microthennometric investigations of fluid inclusions in the Hellyer stringer system indicate that Type I, primary, liquid-vapour inclusions are 10 - 15 J.UIl in size, and yield homogenisation temperatures of 170 - 220¦C in early 2A veins, 165 - 322¦C in main-stage 2B veins and 190 - 256¦C in late-stage 2C veins. These data suggest a waxing and waning thermal history. However, the average salinity remained between 8 - 11 NaCl equiv. wt % in all Stage 2 veins. At Mt Chalmers, Type I inclusions up to 20 urn are found in quartz from the mineralised zone, and these inclusions yielded homogenisation temperatures of 160 - 268¦C and salinities of 5 - 8 NaCl equiv. wt %. Laser Raman spectroscopic (LRS) analysis indicates the presence of CO2 (<1 mole %) in the Hellyer and Mt. Chalmers VHMS systems. Semi-quantitative SEM/WDS microprobe analyses of fluid inclusion decrepitates indicate that the Hellyer and Mt Chalmers ore fluids were enriched in potassium and calcium but depleted in magnesium relative to seawater. PIXE microanalysis of fluid inclusions in quartz also indicates a significant base metal concentration in these fluids. Cation composition and higher salinities relative to seawater suggest that recycled seawater alone cannot be the sole source of the ore fluids. High base metal content and the presence of CO2 in the fluid inclusions imply that magmatic input of ore metals during seawater leaching of the footwall volcanic pile is a distinct possibility.

Jan 1, 1995

By J Wesseloo and Y Kim, Y Potvin, G Mungur, D Grant

At the previous MassMin conference held in Sudbury in 2012, the authors proposed a new framework going beyond dilution and equivalent linear overbreak sloughing (ELOS) for stope reconciliation in relation to the planned stope design. More specifically, the new process investigates performance outcomes including rock overbreak (OB) and fill overbreak (FOB), rock underbreak (UB) as well as geomechanical and operational aspects such as blasting, fragmentation and other production data.Based on the findings of the original 2012 study, a comprehensive data gathering program has been undertaken involving design and reconciliation data from 43 stopes mined between September 2012 and October 2014 at BHP Billiton’s Olympic Dam (OD) operation. The new database structure was based on four types of data:stope definition and performance datastope geometrygeotechnical parametersoperational parameters.The new database allows a more in-depth investigation of stope performance. It is now possible to quantify and analyse UB and OB performance from each wall individually as well as the crown. In this paper, the influence of several parameters on recent stope performance at OD is analysed. The underlying reasons for stope wall performance outcomes are discussed in this paper.CITATION:Potvin, Y, Grant, D, Mungur, G, Wesseloo, J and Kim, Y, 2016. Practical stope reconciliation in large-scale operations part 2, Olympic Dam, South Australia, in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016), pp 501–510 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016

By J Cornejo, A Pinochet, C Caviedes

The ore extraction rate and the incorporation of new areas are key operational parameters. In massive deposits mined by caving techniques they both control the cave back geometry, which is mostly responsible for the induced stress state around productive levels. Early detection of deviations from admissible geometries will prevent stability problems related to geomechanical hazards, helping to improve safety and working conditions and reduce the potential for lost reserves.This paper describes a mine planning tool currently in use at the El Teniente mine. This tool involves the control of the cave geometry based on rules that have been defined as a result of different studies and experience collected during the operational history of the mine.This mine planning strategy achieves an extractive mining process with lower risk than conventional planning methods, ensuring ore reserves extraction if followed as planned while reducing unexpected changes in mining sequences.CITATION:Cornejo, J, Pinochet, A and Caviedes, C, 2016. Geometric control for strategic mine planning at El Teniente Mine, in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016), pp 191–196 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016

THE art of mine surveying has made very great progress in recent years, and is still advancing, perhaps faster than any other branch of surveying. The scope of the mine surveyor's duties has greatly increased, his instruments and methods have improved, the responsibility of his position is greater, and the end is not yet in sight.It might be supposed that such a steadily growing subject would have an adequate literature, but this is by no means the case and outsiders commonly judge mine surveyors by their text-books. Hardly any condemnation can be too strong for most of these books. The English books truckle to the antiquated and crude methods apparently still in use in England, and thereby largely aid in perpetuating them; they commonly in illustrative examples give the distances in fathoms, feet, and inches; they spend page after page discoursing on instruments that should have been forgotten long ago; they try to antagonize theory and practice by detailing such calculations as that a certain vein will contain 2,003.907 pounds of galena per square fathom, and then reduce this amazing quantity to hundredweights, quarters, and pounds. Nothing can be more unscientific, or, for that matter, less businesslike, than unwarranted assumptions of accuracy; it is, perhaps, the greatest curse of applied science. Here we have a calculation to thethousandth part of a pound, when there is probably an unavoidable error of two hundred pounds. What shall we say of a man who explains how to measure the depths of shafts to the hundredth part of an inch by means of short brass rods screwed together...

Jan 1, 1909

By R Shaw, M Hidding

The design of primary sample cutters for high-capacity conveyors is critical to achieving a correct sample, both in collecting the sample and ensuring smooth sample discharge flow. Modelling usually occurs at the design stage and requires extensive experience to achieve the correct result. However, it is difficult to confirm the effectiveness of the cutter design until after installation. Even with high-speed video, confirmation of complete sample capture is difficult, especially if the material characteristics change over time. Recent investigation using discrete element method (DEM) simulation to model the flow of the ore into the cutter and observe how it interacts with the cutter has revealed some interesting design requirements not observed in the past. By including DEM modelling, the correct design and optimisation of the cutter can be more accurately determined prior to commissioning.CITATION:Hidding, M and Shaw, R, 2017. Modelling ore flow in the design of high-capacity sample cutters, in Proceedings Eighth World Conference on Sampling and Blending , pp 145–150 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2017

IN the irregularly shaped ore-bodies of the North Mount Lyell mine by overhead stoping, the method of filling the is a special feature.The situation of the mine two miles from the smelter and mill at an devation of 1000 ft. above the latter, precluded the economical use of granulated furnace or the mill tailings, even if these materials were as suitable for the purpose as the rock nowquarried at North Lyell methods at Mount Lyell have already been described in Proceedings of the Institute.*The breaking the ore in large dome-shaped stopes is still the rule, but the slope or "rill" is much flatter now than formerly. Owing the greater fluidity of the filling now in use, it is sometimes necessary to resort to square-sets, both at the ground floor and above, the roofs and walls are generally enough to permit stoping without timber, except for ground and occasional stacks on the rills.Sufficient area of ground floor has been beaten out to start overhead stoping, the dome back is partly formed, with its apex a rise which connects with the mullock-pass reticulation.(Sce 1 showing this reticulation in diagrammatic form.)

Jan 1, 1927

Applicaton of Agricultural Residues from Pyrolysis in Flotation of Black Coal

Sep 13, 2010