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By B Upton, J Mitchell

The use of hydro scaling and in-cycle shotcrete to replace conventional jumbo scaling, mesh and bolting as the primary method of ground control for run of mine development has been investigated through extensive trials at the Waroonga mine, Agnew Gold Mining Company.These trials have progressed from investigating the productivity aspects of the method through to a three month mine-wide trial, which may yet lead to the adoption of this potentially best practice ground control technique at Agnew.Ov erseas trials and research have shown that hydro scaling results in a significant improvement in the shotcrete-rock bond strength. Good adhesive bond strength ensures that the shear strength of the shotcrete layer rather than itÆs flexural or tensile strength is fully mobilised as rock mass reinforcement.This maximises shotcretes ground reinforcement capability and it is suggested that a bolt-less fibrecrete support design is feasible using the hydro scaling technique.

Jan 1, 2005

By Drury SA, Williams RD, Nind DC

The Airborne Thematic Mapper is an eleven channel digital scanner which acquires image data in the visible, near infra-red, short wave infra-red and thermal infra-red wave- lengths. A description of the system is presented which includes details of the operating wavelengths and performance parameters of the scanner. Consideration is also given to the aircraft installation requirements. During January 1984 the scanner surveyed the mineral rich areas of Leonora, Laverton and Kalgoorlie in Western Australia. This is a region of intense exploration activity for gold and base metals. Some 30,000 square kilometres were systematically surveyed in a period of ten days. This scanner was flown at 7,000 metres altitude giving a ground pixel size of 17.5 by 17.5 metres. The flight line spacing was 8 kilometres. The overall project took some thirty days from conception to completion. The planning and execution of this operation are described in detail. The resulting magnetic tapes provided 11 channels of digital image data over a 30,000 square kilometre area and a variety of image processing techniques were employed in order to capitalise fully on the results. The imagery provides a powerful tool for the geological mapping of the terrain. The data can also be used to monitor the environmental effects of mining operations.

Jan 1, 1986

By G J. Showers, P Botman, A G. Hunt

Iron Road Limited (Iron Road) is currently evaluating the feasibility of producing 21.5 Mt/a of high-grade (>66 per cent Fe) magnetite concentrate from a 3.7 Bt resource (JORC) located at Warramboo on the central Eyre Peninsula in South Australia. Bulk concentrate can be produced via a conventional grind and low-intensity magnetic separation flow sheet. Due to the comparatively coarse magnetite liberation size (106 µm), consideration was given to enhancing both the grind economics and coarser product sizing via gravity separation.This paper outlines the test work, flow sheet design and engineering design of a gravity beneficiation circuit (GBC) conducted by Mineral Technologies for Iron Road. The resulting circuit optimisation necessitated mass balance simulation by Iron Road’s SysCAD model to quantify the resulting changes in mill recirculation load. This included the determination of project-critical grinding power and energy requirements with and without the GBC installed into the primary ball mill classification circuit. The outcome of this work was the design of a GBC, including spirals and up-current classification, which led to a substantial reduction (33 per cent) in ball mill recirculating load and power requirements, together with a favourable coarsening of final product size due to the relatively coarser gravity concentrate. This has led to a significant reduction in project design capital and operating costs. A further benefit of this approach is increased recovery of (paramagnetic) hematite and lesser titano-hematite via gravity separation compared to an all-magnetic separation approach.CITATION:Hunt, A G, Showers, G J and Botman, P, 2015. Test work and design of a gravity circuit for Iron Road’s Central Eyre Iron Project, in Proceedings Iron Ore 2015, pp 139–142 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 13, 2015

Natural gas from the south west Queensland gas fields is now available in north west Queensland to fuel the development of many Carpentaria Mineral Province projects. Like these projects, the south west Queensland gas project, developed under the operatorship of Santos Ltd, has its own æMining CycleÆ. While the project is entering its third expansion phase, it is at the same time actively extending its discovery phase, with large programs of gas exploration and reserves definition. This paper outlines the history of the south west Queensland gas project, with particular emphasis on the relationship of the project to north west Queensland.

Jan 1, 1998

By N L. Turner, D J. Robinson, A J. McFarlane, N M. Chapman, L L. Kuhar, R L. Meakin, R Martin

A number of geometallurgical tests have been developed within the AMIRA P843A Geometallurgical Mapping and Mine Modelling (GeMIII) project, an interdisciplinary collaborative research project involving four research groups and over 20 global mineral companies. Researchers at the Commonwealth Scientific and Industrial Research Organisation (CSIRO) have been focusing on the development of predictive hydrometallurgical indices for the GeMIII project via rapid, small-scale, cost-effective tests and protocols for comparative ranking of attributes relevant to leach performance. One of the focus areas has been the development of a leaching scheme for determination of the mineralogical deportment of copper in a large number of samples for geometallurgical applications.Various leaching schemes have been used over the last 20 years to identify the mineralogical deportment of copper. Typically, weak sulfuric acid and cyanide are used to target copper oxides and æsecondaryÆ copper sulfide minerals, covellite, chalcocite and bornite, respectively. Residual copper is assigned to chalcopyrite and/or bornite. Adaptations of this scheme have included the use of a weak organic acid to target oxides or ferric sulfate to target secondary copper sulfides. Testing of the weak acid/cyanide scheme in the GeMIII project using head and residue QEMSCAN mineralogical data analysed with a statistically reliable comparison method indicated that the inferred mineralogical deportment from various leaches could differ markedly from the theoretical or assumed value. Based on this initial work, test development and leach tests on samples from multiple sites has resulted in the development of a scheme to target copper oxides, chalcocite, covellite, bornite and chalcopyrite. This paper presents results from leach tests conducted on a large sample suite from two pits in a Cu-Au ore deposit with results calibrated using mineral liberation analyser (MLA) mineralogical analysis. This study has assisted in the development of a protocol for determining the mineralogical deportment of copper in a large number of samples for geometallurgical applications.CITATION:Kuhar, L L, McFarlane, A J, Chapman, N M, Meakin, R L, Martin, R, Turner, N L and Robinson, D J, 2013. Calibration and testing of a geometallurgical leaching protocol for determining copper mineralogical deportment, in Proceedings The Second AusIMM International Geometallurgy Conference (GeoMet) 2013 , pp 177-186 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 29, 2013

By J J. Hanhiniemi, M S. Powell

A ‘Variable Blend and Rates’ model is developed for SAG mills which extends upon the JKSimMet® Variable Rates Model. Similarly, a ‘Variable Blend Residence Constrained Perfect Mixing’ Ball Mill model is also introduced, also extending upon the existing JKSimMet® model. These models are used in conjunction with JKSimMet® while employing external technical programs. The technical model is then used to inform an economic model described elsewhere in Hanhiniemi and Powell (2022), which calculate operating and unit costs based on operating conditions, design, and ore characterisation. The SAG and ball mill models include constraints beyond those in the JKSimMet® models. The SAG model constraints include Size Specific Energy (SSE) verification, charge weight limit, and assessment of the impact of media to ore composition in the charge using the SAG Charge SSE Model developed in this paper. The ball mill model includes residence time, volumetric capacity, and SSE verification constraints. These models are applied to Cortez Gold Mine in the processing of two very different ore types and their blends; ‘Horse Canyon’ which is softer in coarser sizes and competent is fine sizes, and ‘Wenban’ which is competent at coarser sizes but softer in fine sizes than Horse Canyon. Horse Canyon also has a finer run-of-mine size distribution then Wenban. The application of the model at this site included undertaking five surveys at varying blends. The behaviours of the blends and individual components is then studied in the SABC circuit. A nonlinearity is observed with throughputs increasing with blending. The newly developed modelling approach captures these responses. Controlled blending based on ore competence-by-size and size distribution was implemented by the site, which then realised significant improvements in throughput without any capital cost (Ntiamoah et al, 2020). The modelling developed in this paper is then compared to existing practice, and the new method was found to provide improved fidelity and utility. A three-dimensional surface is then developed using the model describing the SAG mill throughput capacity at varying conditions (speed-filling) versus varying blend. The change in throughput as a function of only the changing charge composition is presented. The result is nonlinear, and explanations are provided to describe this behaviour.

Aug 24, 2022

The Sishen iron-ore-mine produces 3 pro= ducts with size gradings of 25 to 8 mm, 11 to 5 mm and 5 to 0,2 mm and has a product capacity of 20 Mtpa. Ore is produced at an average Fe content of 66,2 % Fe for the two coarser pro= ducts and an average of 65,3 % Fe for the fine ore product. Three stage crushing is practised to re= duce the run-of-mine ore to -90 mm after which it is screened into five different size frac= tions of which four are heavy media beneficiated in static baths and cyclones and the fifth frac= tion discarded to slimes dams. A final three stage crushing and screening process is employed to produce the final three Products which are homogenized by means of blen=ding systems nrinr to despatch.

Jan 1, 1987

The perception of New Zealand as an exploration destination has improved compared with other countries. There has been a realisation that New Zealand's potential is greater than previously thought. Other countries are not as attractive as before, and explorers are looking at alternatives that are geologically prospective and politically stable.   New Zealand is regarded as geologically prospective, especially for gold, with potential for world class deposits. It is also prospective for other metals, coal and industrial minerals. New Zealand is politically stable, and has an economy that is attractive to overseas investors. It is one of the least corrupt countries in the world, which overseas companies see as providing a high degree of certainty for investment.   New Zealand has good opportunities for investment in gold exploration at present. Otago has been the focus for new companies and is the favoured exploration location. Otago is regarded as very prospective, and hosts New Zealand's largest gold deposit at Macraes. There is potential for other similar deposits elsewhere in Otago.   The mineral industry previously had an excessively pessimistic view of New Zealand, which has resulted in little new investment in New Zealand for some years. Previous pessimism is turning to optimism, and there is increasing interest in New Zealand as an exploration destination by overseas explorers.

Jan 1, 1997

The history and milestones in the evolution of support systems utilised in the mass-mined chrysotile mines of Shabanie and King are discussed in detail. The use of block caving, false footwall or sublevel caving mining methods brings with it some major support problems, which are exacerbated, in our low rock strength mining environments. The paper discusses the various support elements and systems that have been used successfully or otherwise in these operations. Some predictions for the future of rock reinforcing in our ground conditions are highlighted, in relation to geomechanics, levels of mechanisation and production risk analysis.

Jan 1, 2000

By R Badreddine, J Rose, L De Windt, P Chaurand, L Raimbault

Municipal solid waste of incineration (MSWI) bottom ashes are recycled as aggregates in civil engineering. These heterogeneous materials are composed of crystalline and glassy solid phases which contain trace metals, presenting a potential risk to the environment. Secondary ion mass spectrometry (SIMS) can provide quantitative chemical information, in particular the localisation of metals at trace level. Unstable glassy phases formed during incineration are present in relatively high proportions. Their analyses suggest a continuum between melilite-bearing glasses and dark glasses enriched in iron with abundant spinel aggregates. These primary glasses are enriched in zinc (~4500 ppm) but depleted in lead (~800 ppm) by comparison with the bulk chemical composition and reference materials. Heterogeneous cementing and encrusting admixtures on coarse grains are studied in a second step. SIMS imaging suggests a superposition of band zones including an intermediate layer enriched in iron oxyhydroxides and a superficial layer with calcium accumulation. A strong spatial association between lead and iron is systematically observed. Extended X-ray absorption fine structure (EXAFS) supports these observations by demonstrating that lead co-precipitation within iron oxyhydroxides, or sorption on their surfaces, may be a main containment process in the cementing and encrusting admixtures, whereas lead speciation is globally more complex in MSWI bottom ash.

Jan 1, 2008

The Cannington silver lead zinc deposit is located near Mt Isa in North West Queensland. This world class orebody is owned by BHP World Minerals (BHP) and is estimated to contain 45 million tonnes of ore at an average grade of 11 per cent lead, four per cent zinc and 500 grams/tonne silver. At BHPÆs planned 1.5 Mtpa extraction rate, the mine life will exceed 20 years. Construction of the underground mine, which commenced in August 1993, was carried out by Peabody Resources Ltd (Mining Services Division) (PRL) for BHP Minerals Pty Limited (BHP) under contract packages totalling approximately $100 M using several innovative techniques to deliver safety, quality and time related project goals. Client/Contractor Partnering, resulting in harmonious working relationships, a combined commitment to the achievement of an excellent safety record, and a seamless transition from the construction phase to operation of the mine, has been a feature of the project.

Jan 1, 1998

By Robinson T

The paper describes a spreadsheet system that enables selection of projects and companies that meet the user's corporate exploration and/or acquisition philosophy. A regularly maintained commercially available database has been used as the basis for this system. It provides an easily accessible efficient com- prehensive search method. The technique enables ranking by various criteria, both technical and financial, to provide groups of projects/companies that are of interest. Initially, target size parameters such as reserves, production and mine life are applied together with geological criteria such as age and deposit type; the significance of the targets in the context of the Australian gold industry is addressed.

Jan 1, 1988

Cretaceous volcanic activity (Hauterivian Albian) in the Peruvian Andes can be found along the coast of Peru and the western edge of the Andes mountains between 15o30'S and 5o30'S, extending discontinuously in south to Chile and north to Ecuador and Colombia. This volcanic activity formed in three aborted marginal basins; the NNW-trending volcanic Ca±ete and Huarmey, and NNE-trending Lancones basins. These volcanic rocks are predominantly andesitic and basaltic in composition, of calc-alkaline and tholeiite affinity with subordinate dacitic and rhyolitic rocks. One notable feature is the appearance of æocoitasÆ from Ica (14oS) south to Santiago de Chile. These rocks have a calc-alkaline to alkaline affinity. From south to north, the continental crust gradually becomes thinner, allowing mantle material to rise towards the surface. Ophiolitic sequences of this type form a marginal basin in Colombia. Very low-grade regional metamorphism which affects the volcanic rocks also varies gradually from south to north. Between Santiago de Chile and Ica this takes the form of burial metamorphism, with moderate geothermal gradients (20o-30oC/km). Metamorphism in the Huarmey basin is transitional between burial and ocean-floor metamorphism, with very high geothermal gradients (>3000C/km). High geothermal gradients are also apparent in metamorphism of the Lancones basin, though less than the other basins. Ocean-floor metamorphism is present in the ophiolitic sequence in Colombia. Associated mineral deposits in the Huarmey and Lancones basins, and in the north, are of the volcanic massive sulphide-type (VMS). The principal deposits in Peru are Leonila Graciela (20 Mt Zn and Pb) and Tambogrande (40 Mt Cu and Zn). There are also smaller mines and prospects. To the south of Lima, manto-type Cu deposits (CuMT) are found with a mineralogy of chalcopyrites, pyrites, magnetite, actinolite and apatite. The main example is Raul Condestable (10 Mt Cu). Other prospects are present to the south and Chile has some very large mines of this type (El Soldado, Lo Aguirre). The notable differences between the CuMT and the VSM deposits are thought to be the result of the prevailing conditions in the earthÆs crust during the Hauterivian Albian. To the south, calc-alkaline and alkaline volcanic activity in aborted marginal basins, with thicker crust, was thick, produced moderate geothermal gradients associated with burial-type regional metamorphism and deposits of CuMT. In the north aborted marginal basins associated with calc-alkaline to tholeiitic volcanic activity and a gradually thinning crust, produced transitional regional metamorphism between burial-type and ocean-floor type, associated with high to very high geothermal gradients and VMS deposits. In Colombia these conditions led to ophiolite extrusive rocks, ocean-floor metamorphism and also VMS deposits.

Jan 1, 1999

The Que River and Hellyer polymetallic massive sulphide ore bodies are located 3 kilometres apart in the Cambrian Mount Read volcanics of Western Tasmania. Both deposits are classic examples of the Kuroko volcanogenic style. Base and precious metal rich hydrothermal solutions rose through a deep fracture system and vented on the sea floor, causing sulphides to accumu- late in adjacent topographic lows. Together the preproduction geological resource is approximately 23 million tonnes at greater than 18% zinc plus lead, with economically significant silver and gold. Exploration by Aberfoyle in the Mount Read volcanics com- menced in 1970. Que River was discovered in 1973 following a comprehensive data review, a regional stream geochemical survey and a helicopter-borne electromagnetic survey. Production began in 1981, and the mine is currently producing 300,000 tonnes per year. The ore is sold to the Electrolytic Zinc Company of Aus- tralasia Ltd mill at Rosebery. Ten years of extensive geological mapping, soil geochemistry, and induced polarisation, combined with continual study of the Que River orebody and its host rocks, formed a strong frame- work for the discovery of the Hellyer deposit, which was found as a result of drilling .a subtle time domain electromagnetic anomaly in 1983. Hellyer is currently being mined at a rate of 250,000 tonnes per year, with the ore being concentrated at Aber- foyle's converted Cleveland tin mill. Treatment of 1 million tonnes per year will begin in early 1989 at a new mill located near the Hellyer site.

Jan 1, 1988

In October 2005 Phelps Dodge mining, a US based company, visited several Australian mining companies and mine sites to ascertain the current applications of risk management methods in the organisation. The results of this review, documented by the author, indicated a ælayeredÆ approach from high level site or major hazard analysis through to face level, æstop and lookÆ, methods. The approaches of several companies were summarised in one simple layered model. This model is helpful to other sites and companies to identify potential improvements but also offers an image of best practice that may assist with the governance of OH&S by both company boards and community regulators. The issue is particularly relevant as we discuss national consistency in mining regulation. This paper examines the layered model, the company and site approaches that helped define the model, as well as the suggested implications of the layered model to governance.

Jan 1, 2006

By A D. T Goode

Data Metallogenica (DM) is unique as a global mineral sample collection and deposit database with over 70 000 rock samples and a wide range of descriptive, photographic and measurement data. Subscribers have access to approximately four gigabytes of on-line data with many examples included on the public pages. DM commenced its life on the Pacific rim in 1971 and much recent growth has focused on countries of the Pacific margin, particularly Australia, Fiji, Chile, Indonesia and Peru. Approximately 600 separate deposits and mineral occurrences in this region are represented in DM. The sets of rock samples have been photographed at high resolution and included on the web site, together with unpublished descriptions, deposit cross-sections, bibliographies, field and mine photographs, petrology and reflectance mineralogy. Figures and abstracts from PhD theses are a new addition and the donation of proprietary databases by companies and individuals is an encouraging trend. DM increasingly is being viewed as an acceptable and important repository for æfragileÆ and irreplaceable personal and company data, it is also being recognised in its true light as a high level information system, not solely a collection of rock samples. Data Metallogenica is a not-for-profit venture of AMIRA International that requires self-funding from December 2004. Growth and development must be funded entirely out of subscription and sponsorship revenues because no government subsidy is provided. The Pacific rim is in the mainstream of mining and exploration activities worldwide and those involved have much to gain from a dynamically sustaining DM. The home page at www.datametallogenica.com contains much example data and details of subscription and membership rates.

Jan 1, 2004

By T Napier-Munn, E Louwrens, L Keeney

Geometallurgical characterisation of ore deposits is accepted practice in some parts of the mining industry today. Its primary aim is to provide constrained inputs that reflect inherent geological variability and its impact on metallurgical performance for the deposit. Geometallurgy improves project value because it suggests more valuable alternatives for scheduling and processing through an increased knowledge and understanding of the interactions of rock properties and extractive technologies. Lower project cost (both capital and processing) and improved recoveries are the result from closer tailoring of the mining and mineral processing strategies to the characteristics of the resource (Dunham, Vann and Coward, 2011). Tailings storage facilities (TSFs) can be seen as potential resources and it is argued that fundamental geometallurgical characterisation as applied in ore deposit characterisation should also be applied to planning the retreatment of TSFs. This paper will describe a research project at Julius Kruttschnitt Mineral Resource Centre assessing if geometallurgical principles and methodologies can successfully be applied to TSFs as they have been to primary deposits. The project is establishing a new standard method of tailings evaluation which will include a 3D spatial model of the tailings resource. Initial domaining of the TSFs was done using principal component analysis followed by k-means cluster analysis based on chemical assays from drill core samples. The subsequent characterisation of the drill core samples has involved chemical, mineralogical and metallurgical profiling, with a range of metallurgical tests being conducted on the samples. This characterisation step is followed by class-based analysis, predictive modelling and process performance domaining with the ultimate objective of establishing a 3D spatial model incorporating geochemical, mineralogical and metallurgical performance data. This approach, which takes into account processing performance permits a more realistic (as compared to doing limited chemical assays and metallurgical testing) economic evaluation of the potential of reprocessing the tailings material. It is believed that the approach is generic and can be applied to other TSFs being considered for reprocessing. The present case study has also established the gold, copper, magnetite and cobalt deportment for an iron oxide copper-gold deposit tailings resource.CITATION:Louwrens, E, Napier-Munn, T and Keeney, L, 2015. Geometallurgical characterisation of a tailings storage facility – a novel approach, in Proceedings Tailings and Mine Waste Management for the 21st Century , pp 125–132 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 27, 2015

By Hawkins L. V, Seedsman K

A combined reflection seismic and magnetic survey off the south coast of New South Wales has revealed six distinct reflection horizons within the Lower Triassic- Upper Permian sequence, and has enabled the upper part of the Illawarra Coal Measures to be mapped in considerable detail. Large magnetic anomalies in the eastern half of the survey area appear to originate in the Gerringong Volcanic Sequence which forms the magnetic basement in this survey. Small residual anomalies in the western half of the area can be correlated with small scale faulting and folding in the uppert part of the Illawarra Coal Measures, as revealed by the seismic reflection survey. A synclinal axis striking at approximately 55¦ has been mapped near the western margin of the survey area, and areas of faulting and folding have been outlined by com- bined analysis of seismic and magnetic results.

Jan 1, 1969

Although AustraliaÆs coal mining industry is currently experiencing a pleasing period of price relief, long-term trends toward lower real prices will surely continue. Higher price levels attract expansion by existing operators and market entrance by new operators. History clearly demonstrates the relentless long-term march toward ever lower real prices. Therefore, the need for economic returns applies constant pressure to improve productivity. To be sustained, high productivity requires a systematic response based on a solid understanding of critical productivity determinants. The most powerful determinant of productivity is now widely understood to be workplace culture. Culture largely comprises a combination of behaviours, symbols and attitudes. This paper will examine and review scienceÆs latest discoveries in human behaviour. It will provide a proven, practical framework for understanding behaviour and applying this knowledge. Significantly, it will highlight why conventional approaches toward improving productivity often provide disappointing economic returns. The modern understanding of behaviour factors will cover coal face operations. More importantly, because executive and managerial levels in coal mining have significantly greater impact on industry and mine productivity the paper will concentrate on leadership. Particular emphasis will be placed on use of modern systems and in particular use of what are by far the most powerful drivers of behaviours û measurement, analysis and reporting systems. The paper and presentation will show how conventional systems rooted in antiquated American legislation from the early 1900s stifle productivity improvement and drive suboptimal and even counterproductive behaviours. These commonly used systems will be compared with accurate and effective modern methods for assessing performance to improve productivity. These principles are proven in all industries and effective application in mining will be highlighted. Actual results will be used to demonstrate practical approaches successfully applied in both metal and coal mining in Australia and overseas.

Jan 1, 2005

During the period 1981 - 1991, Esso Australia and their Joint Venture partners have discovered about 180 MB of liquids (crude and condensate), 60 MB natural gas liquids and 800 - 1000 GCF of gas. A total of 48 wildcat wells were drilled including 12 new pool discoveries drilled from platform facilities. Significant discoveries include the West Tuna, Kipper, Blackback and Terakihi fields. These four discoveries, contribute to 75 per cent of the total reserves discovered in the last decade and were all high-risk plays. The Kipper discovery, in the pre-Latrobe Golden Beach Group top sealed by volcanics, and the Blackback-Terakihi discoveries, located on the present day continental slope in water depths ranging from 300-700 metres are both the result of successful drilling outside the traditional exploration bounds for the basin. During the last decade, Esso and its partners have spent about A$400M on wildcat exploration activity. The exploration success rate, excluding platform based drilling, has been 50 per cent for wildcat wells. On a technical front, the last decade has heralded substantial improvements in seismic data quality. Peak frequency content in seismic data at the Latrobe Group target levels is now double that of the early 1980s. Significant advances have also been made in our understanding of sequence stratigraphy, geochemistry and geohistory of the basin.

Jan 1, 1992