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By S M Richardson, A W McNeill, J B. Gemmell

"An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation. The Hellyer, Fossey, Que River and Mount Charter volcanic-hosted massive sulfide (VHMS) deposits occur within the Que-Hellyer volcanics of the Mount Read volcanics, Tasmania. These deposits occur along a 6 km strike length and are hosted by the same stratigraphic unit. We use a combination of whole-rock geochemistry, short wavelength infrared (SWIR) spectrometry, laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) analyses and compiled historic whole-rock geochemical data to develop district-scale vectors towards VHMS mineralisation.Strongly sericite and K-feldspar altered rocks concentrate along a linear trend from Hellyer, through Que River, to Mount Charter. Ishikawa alteration index values and whole-rock major and trace element concentrations provide exploration vectors towards mineralisation on a regional scale as significant enrichment and depletion trends. On a deposit scale, composition variations in white mica (sericite alteration), chlorite and K-feldspar are observed and reflected in whole-rock geochemical variations. Regional SWIR data from drill core support the prevalence of phengitic mica and high-Mg chlorite within footwall alteration halos and highlight the main upflow zones of hydrothermal fluids in the VHMS district. The combined use of regional whole-rock geochemistry, SWIR and mineral chemistry is an effective way to highlight prospective areas for VHMS mineralisation in a mature exploration province.CITATION:Wu, S, Gemmell, J B, McNeill, A W and Richardson, S M, 2015. Exploration implications from variations in whole-rock and mineral chemistry around the volcanic-hosted massive sulfide deposits of the Que-Hellyer volcanics, Tasmania, Australia , in Proceedings PACRIM 2015 Congress, pp 85–90 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 18, 2015

The radiolarian biostratigraphy of the western part of the Gympie Province, north of Brisbane, has been examined. This part of the province comprises mainly the Amamoor beds and the Gympie Group, which have been assigned Permian ages on the basis of localised marine macrofossils. This study has shown that the Amamoor beds and the Gympie Group include older strata than previously supposed.The Amamoor beds consist of at least two tectonic units, namely a melange unit (unit A) and a well stratified sequence of sedimentary rocks (unit B). The former unit, regarded as an accretionary subduction complex, contains chert blocks ranging from Late Devonian to Earliest Carboniferous, while the latter unit yields Permian radiolarians. Latest Devonian to Earliest Carboniferous bedded cherts occur in sequence previously mapped as Amamoor beds and Gympie Group.

Jan 1, 1990

By R Farana

The future challenges in mining instrumentation, mainly on future intelligent mines, are to continue providing instruments with the highest level of reliability at the lowest possible cost, and also to take advantage of technology existing in other industries and to adapt it to the mining context. New wireless instruments (smart sensors, smart actuators, smart controllers) would also be very useful, as well as instruments fully adapted to the monitoring of large movements that are observed, in both underground and open pit mines. Mining instrumentation is found to various degrees in most mines, both open pit and underground. Smart mining instruments present a certain number of aspects specific to the environment in which the instruments are installed. Namely, the instruments can be installed either for short-term or long-term purposes. The mining industry is always looking for useful instruments that can provide relevant information on ground behaviour adjacent to mining stopes or permanent infrastructure. The instruments must meet the various criteria, and must also evolve with the new mining technologies that are continuously being implemented. A strong collaboration between the mining industry, research organisations, and instrument manufacturers is the key to meeting these objectives. This contribution describes the current trends on smart sensors and smart instrumentation with Wireless LAN support.

Jan 1, 2003

Ventilation challenges are often encountered when an underground mine expands to new zones and it often is the case to make a thorough review of the existing system and assess immediate and future airflow needs at the desired quantity and quality. An unexpected mine plan change that calls for increased development and production from new areas can impose a strain on the existing ventilation system. Budgetary constraints can also demand creativity in design on the mine ventilation engineerÆs part. Since the addition of several mining horizons it had become obvious at the Meikle mine that something had to be done to increase airflow quantity and quality in the old main zones because most of the ventilation resources had been channelled for development in the new mining horizons. An airflow assessment of the existing system had to be performed and it was determined that the airflow quantity had to be increased by at least 30 per cent and the quality of the air had to be improved by reducing nuisance and respirable dust and at the same time reducing the airflow temperature before it was used in a few mining zones. At the conclusion of the airflow assessment it was determined that a third centrifugal fan would be installed on a new 3.05 m diameter borehole from surface to underground. By a careful study of temperature conditions over time it was determined that an evaporative cooling spray chamber would be sufficient to cool the airflow down from the high dry bulb temperatures observed down to saturation at the wet bulb temperature. At the same time excessive nuisance dust generated as a result of the airflow travelling a long way in a haulage drift will be knocked down in the spray chamber resulting in cool, clean air in the mining districts. Expansion of the existing surface ammonia refrigeration plant was out of the question for several reasons. The fact that the airflow was hot and dry meant that evaporative cooling spray chambers could achieve lower working temperatures at a very low cost compared to the expansion of the chilled water plant. The expansion of the ventilation system at Meikle mine and the use of evaporative cooling spray chambers were demonstrated to be very successful and the information presented in this paper can be of benefit to other mines experiencing the same ventilation problems as was the case at the Meikle mine.

Jan 1, 2005

Direct seeding or regeneration of vegetation in Australia has been occurring in nature for about 400 million years! From the 1870's till the 1930's, direct seeding by man was used in the south-west of Victoria as a method of re-establishing native vegetation on broadacre farmland. The introduction of improved exotic pasture grasses and the wide-spread use of superphosphate from the 1930's lead to its demise as a farmland revegetation technique.

Jan 1, 1992

By R McIlwraith, B Breul

Two case studies are presented in this paper. The first one discusses a roller compacted concrete water supply dam that was constructed in El Mauro in Chile to provide water for agriculture activities downstream of a copper mine during the dry season. The 23 m high dam used a bituminous geomembrane (BGM) as the low permeability upstream facing element on the dam to control seepage through the dam. This is the first time that a BGM has been used in this application. A deep cut-off trench was used to control seepage beneath the dam and through the abutments. This paper briefly presents the design of the dam, including selection of the concrete mix and maximum aggregate size that the use of the Coletanche BGM allowed, and provides details of the construction, quality control and assurance of the installation of the BGM. An ultrasonic apparatus was used as part of the quality control on the BGM seams.The second case study discusses a tailings dam in Cerro Lindo, Peru (near Chincha), where a watertight BGM was installed on the upstream face. Results are presented of the survey done by a consultant on the behaviour of the dam and in particular of the BGM following an earthquake of magnitude 8.1 in Chincha close to the site. These findings on-site were checked by trials in a laboratory in California. Test results are given and explained.CITATION:Breul, B and McIlwraith, R, 2015. Case histories – roller compacted concrete dam waterproofing with a bituminous geomembrane in Chile and a tailings dam in Peru subject to an earthquake of 8.1 magnitude, in Proceedings Tailings and Mine Waste Management for the 21st Century , pp 367–372 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 27, 2015

By C Sylvestre

For the last 50 years, traditional safety management has improved safety performance by: • Fixing the environment (eliminating the hazard). • Improving the system (more/less rules, procedures etc). • Making safety more conscious (more/better interactions about the importance of safety). Although these approaches certainly have merit, and may be part of an overall solution, they are not enough to prevent many modern-day incidents. Today, these three approaches are used more than before, and are used better than ever before. Yet, workplace fatalities in Australia have stagnated from 2013 to 2019, as have the number of incidents, even serious ones. In the USA, workplace fatalities have increased by 15 per cent in the same period.

May 5, 2022

By Stanojevic R, McGlinn PJ, Day RA, Levins DM

This paper reports the results of a number of studies that Ansto has carried out for mineral sands companies concerned about low-levels of naturally-occurring radioactivity in their products. Where measured levels of radioactivity have exceeded allowable levels, Ansto has used specialised techniques to identify the source and distribution of the radioactivity and investigated processing strategies to remove the Contamination.

Jan 1, 1993

The outlook for suppliers of energy to the expanding economies of the Pacific Basin region is essentially positive, but particularly for exporters of high quality steam coal. This paper argues that economic growth in the Pacific Basin region has exceeded world economic growth for some years and that this will continue to be the case for the next decade at least. It looks briefly at the link between economic growth and energy demand and at the relationship between energy demand and the demand for electricity. Changing preferences in fuel mix for electrical generation in the region are noted and tentative forecasts made about variations in this mix. The pros and cons of various forms of fuel used to generate electricity are considered from the point of view of the consumer. Having concluded that steaming coal in particular is likely to become even more important as a generator of base load electricity, the paper looks at the opportunities this presents for exporters such as Australia, and touches on some factors that could prevent development of those opportunities. This paper will concentrate on electrical energy. For the purposes of this paper, the Pacific Basin refers essentially to Australia, New Zealand and the Asian countries bordering the Western Pacific. As a supplier, Siberia is not included because, although it has great potential, it is thought that problems of climate, infrastructure and political restructuring will delay the realisation of that potential until the next century. Although it deals with the Pacific Basin region, where many countries are industrialising rapidly from a predominantly agricultural base, it looks at the experience of mature industrial DECD economies where their experiences seem relevant.

Jan 1, 1990

Mining regulatory authorities worldwide mandate frequent inspection of winder ropes used in shaft-equipped underground mines and ski lifts. Visual inspections are effective in identifying and assessing the type and severity of damage found in the exterior of the rope. In addition, electromagnetic or permanent magnet-based methods are used to identify broken wires, corrosion damage and other anomalies that occur anywhere within the core of wire ropes made of steel, which is a ferromagnetic material. The magnetic methods yield the loss of metallic area due to wire breaks and other damage in the ropeÆs section as well as local flaws that give rise to discontinuities in the magnetic field. The quantitative measurement of the loss of metallic area is indirectly related to the loss of breaking strength that is commonly used as a rope discard criterion. The ropes used in a mine winder in the Goldfields of Western Australia are inspected using Meraster 120B permanent magnet-based rope tester and their condition is assessed against published discard criteria.

Jan 1, 2003

Feasibility studies in the development of mining projects are fundamental to most investment decisions. It is important that the issues addressed and the degree of detail involved in feasibility studies are consistent with the investment decisions to be taken. Emphasis should be placed on a thorough analysis of critical project parameters prior to detailed investigations being undertaken into other activities which are not relevant to the decisions at hand. Therefore, the issues to be decided upon should be influenced significantly by the stage of development of the project and by the reliability of technical and financial information used in the study. Some of the more critical parameters of feasibility studies are commodity prices, inflation rates and discount rates. Advice is given on the selection of these inputs and also on their application in the feasibility study as the project progresses through its various development stages. The feasibility study should involve not only a formal evaluation of project economics but also an analysis of all project related risks and a comparative analysis of projects competing in

Jan 1, 1983

By OÆGrady P

Finite element analysis is becoming a routine component of design of longwall extractions, now superseding more traditional somewhat intuitive approaches. Finite element modelling is relatively inexpensive and provides an adequate degree of similitude to give satisfactory analysis. The physical modelling of two decades ago is now largely replaced by numerical methods of which finite element is the best known. Important data for finite element work are physical properties, including creep aspects, introducing the non-linearity of stress response.Various computer packages are available and some were used to model two specific UK examples, using both linear and non-linear approaches. It appears that non-linear approaches will yield most benefit. The use of materially non-linear analysis is merited by the greater similitude it provides between model output and real mine situations.

Jan 1, 1991

By M Xu and, P F. Wells, A N. Kerr, Y Shields

Triethylene tetramine (TETA) has been used in combination with sodium sulfite (sulfite) for pyrrhotite depression at Clarabelle Mill since 1998. This combination has been highly successful at reducing pyrrhotite levels in the bulk (Ni/Cu) concentrate. Although highly effective, the roles of TETA and sulfite are not well understood. Treating bulk samples of the circuit feeds through the miniplant enabled the effects of circuit configuration on the performance of the pyrrhotite rejection circuits at Clarabelle to be determined. Reasons for the different performance of the non-magnetic pyrrhotite rejection circuit in the miniplant were investigated and tested in the laboratory. The effect of different grinding environments in the laboratory was examined to better understand the depressing mechanisms of TETA/sulfite. Modification of the grinding chemistry improved the selectivity of pentlandite over pyrrhotite in the presence of TETA/sulfite at current plant dosages.

Jan 1, 2005

By Moore J

Gunpowder Copper Ltd is using in-situ leaching to extract copper from the Mammoth sulphide ore deposit in north-west Queensland. To increase metal recovery, ore is fragmented using conventional underground longhole drilling and blasting techniques. Although the upper levels of the orebody had previously been mined by open cut and underground methods, significant reserves of copper existed around old workings. To safely and economically recover this resource, a decision was made to fire the remaining pillars in the upper part of the mine by a single 1.37 million tonne mass blast in February 1992.This paper records the planning, design, and implementation of the Mammoth mass blast. Geological and geotechnical aspects are summarised, to explain the reasons for such a large blast. Drilling, charging and blast initiation are discussed in detail, to show how standard equipment and products were applied to a unique task.

Jan 1, 1992

A study of the electrolysis of PbS in molten PbCl2 showed cathode efficiencies which increased with current density at fixed sulphide concentrations, and decreased with increasing sulphide concentration at fixed current densities. The anodically produced sulphur dissolved rapidly in the melt, the rate increasing with temperature and sulphide concentration. Experiments with diaphragm cells, made to determine the relative effects that dissolution of lead and sulphur have on the cathodic current efficiency, demonstrated that dissolution of sulphur was the major contributor to the lowering in efficiency.

Jan 1, 1973

HAPPENING to be in Cue recently the writer was unexpectedly called upon to make surveys of some diamond drill bores on the Big Bell mine on the Murchison goldfield. The owner of the mine Mr Herman Mandelstam. had brought such apparatus with himas he could lay his hands on. and no other was available without prohibitive delay.The usual method of making these surveys as is well known is by putting a glass tube half filled with gelatine or glue in a melted state down the hole with a small magnet freely suspended in the glue and having it there till the glue sets solid. When this tubeis withdrawn (its depth down the bore being noted) the bearing and inclination of the borehole at this particular point can be read - the bearing by the compass and the inclination by the angle between the tube and the surface of the glue which of course ishorizontal. By taking a number of these observations according to the degree of accuracy required the course of the bore can be fairly accurately plotted.In dealing with dry holes there is little trouble but when the holes are full of water great difficulty is experienced. In the case in point the first observation was made in water 300 ft. deep, corresponding to a pressure of 130 lb. per sq. in. The tube containing the gelatine and glue (a mixture was used) was found, when hauled to the surface, to be completely filled with a weak mixture of water, gelatine, and glue and there was no horizontal surface from which to measure the angle of inclination of the bore. The water had been forced through the corks and sealing wax with which the tube had been closed. After several attempts it became obvious that no method available would keep the water from getting into the air-space in the tube, and to a pressure-proof metal container was impossible, nothing remained but to do away with the air-space and this was accomplished by using two liquids of different specific gravity - mercury and melted glue. The tube...

Jan 1, 1930

Pressure drops were measured in a column packed with glass spheres and wax particles, both in random and preferential distributions. Variables investigated included wax content, gas flow rates, and temperatures.It is shown that for random distribution of wax, pressure drop is exponentially related to wax content above the melting point of wax and that below this it increases with increasing gas rate and temperature.For preferred distribution of wax the highest increase in pressure drop is obtained with horizontal distribution of wax and the least with vertical distribution.Comparison with operating blast furnace data and application of results to practice are also included.

Jan 1, 1970

Caving is the lowest cost underground mining method, provided that drawpoint spacing, drawpoint size and ore handling facilities are designed to suit the caved material and that the drawpoint horizon can be maintained for the draw life. In the near future several open pit mines that produce in excess of 50 000 tons per day will have to examine the feasibility of converting to low cost, large scale underground operations. Several other large scale, low grade underground operations will experience major changes in their mining environments as large dropdowns are implemented. These changes demand a more realistic approach to mine planning than has occurred in the past, where existing operations have been projected to increased depths with little consideration of the change in mining environment that will occur. As economics force the consideration of underground mining of large, competent orebodies by low cost methods, the role of cave mining will have to be defined. In the past caving has generally been considered for rock masses that cave and fragment readily. The ability to define cavability and fragmentation, the availability of large, robust LHDs, a better understanding of draw control requirements, improved drilling equipment for secondary blasting and reliable cost data have shown that competent orebodies with coarse fragmentation can be exploited by cave mining at a much lower cost than with drill and blast Methods.

Jan 1, 1995

The effects of changes in sintering bed height, coke fuel, suction and basicity on sinter productivity, physical strength and mineralogy were determined. It was found that, for a given iron ore, there is a narrow -coke range which maximises sinter strength, irrespective of bed height (in the range 300 to 500 mm) or basicity (in the range 1.2 to 2.2). Increases in bed height, at a constant coke level, improved the physical strength of the sinter. Productivity increases were obtained by increasing the sintering suction but, at coke levels other than the optimum, these *ere somewhat offset by the decrease in sinter physical strength. At basicities higher than 1.2 (i.e. 1.6, 1.8 and 2.2) there was a narrowing of'the size range of product sinter, with a decrease in the percentage of top size material, and a decrease in the amount of fines produced. Changes in coke, bed height and basicity exert major effects on sinter mineralogy, while the Nagoya index was mainly influenced by cote and bed height Changes.

Jan 1, 1975

After a short presentation of the Division of Mining at the Royal Insti- tute of Technology, Stockholm, Sweden, the author presents some of-the fill research carried out at the Division. Literature surveys and testing methods and equipment are described. The use of flocculants' in hydraulic filling has been tested both in laboratory and in mines and the results are very promi- sing. Finally compressibility investi- gations and some finite element calcu- lations are presented.

Jan 1, 1973