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Thirty six different commodities were recorded from 3708 mineral occurrences in the Atherton 1:250 000 Sheet area, mapped by personnel of the Queensland Department of Resource Industries. Tin, occurring in 56% of all mineral occurrences, is the most common, followed by copper, tungsten, silver, lead, gold, fluorite molybdenum, zinc and antimony. The densest area of mineral occurrences is the Herberton Mineral Field, one of the most intensively mined areas in the state.The majority of occurrences in the sheet area are fracture, fault or shear related vein or lenticular deposits, with subordinate types being pipe, skarn, endogreisen, disseminated and porphyry copper deposits. However the larger mines in the area are commonly of the subordinate types including the Red Dome gold-copper skarn, the Wolfram Camp and Bamford Hill tungsten- m olydbenum endogreisens, and the Vulcan pipe tin deposit. Significant gold prospects occur in quartz-antimony veins, breccia pipes and skarn deposits associated with rhyolitic porphyry dykes. A fluorite-gold association has been noted in several areas on the western side of the sheet.Mineralised fractures are predominantly oriented in a NNW direction which is the major trend in the Hodgkinson Province. Secondary N and NE directions are also present.

Jan 1, 1990

By S B. Sheldon

Wall control programs tend to be expensive and consequently require financial justification in order to get approval for the expenditure required. The difficulty faced in getting this approval is that the outcomes of a wall control program are all subjective – a prediction of wall stability and what the wall would do with and without the program. Determining a net benefit is difficult and often justification of a wall control program is based on gut feel, history and a good selling campaign to build a perceived need.This paper outlines a simple solution to this problem by applying risk management principles to wall control. The process is to identify the risks to the operation associated with current wall conditions and then build a risk database for different potential scenarios for each risk. A financial impact is assigned to each risk scenario to complete the database. A consequence and likelihood analysis of each of the risks is undertaken and a formula applied to estimate the projected cost to the operation for the current risk profile. The process is repeated for the predicted wall control conditions after the application of the wall control program. A successful wall control program will reduce an operation’s risk profile so this projected cost should be less than that calculated for the current scenario. The difference in the two projected costs is the value that the wall control program has produced and this value can be used to determine the net financial benefit potential for the wall control program.This methodology can also be applied to other improvement programs that focus on risk reduction such as vibration control.

Nov 8, 2011

By R M. Lonsdale, M D. Goodz

"With an ever-increasing dynamic business environment, successful stakeholder engagement is becoming more fundamental to achieving desired outcomes in today’s mineral resource industries. It is imperative to be proactive in correctly identifying all stakeholders and initiating early contact. This builds trust relationships, which are essential to ensure future decision-making processes are streamlined.Often neglected is a company’s obligation to select the correct team to represent its values and mission. The company requires representation that demonstrates an understanding and commitment to its operations and people, the safety and health of the community and environment, and most importantly, represents the decision makers. Stakeholders need to believe that the engagement process is genuine and that the company representatives are aligned towards targeted outcomes that will benefit all stakeholders in some way.Among others, stakeholders include shareholders, staff, families, community, service and supply providers, regulators, land managers and the political/financial framework. Depending upon the mineral product, stakeholders may include ports, international offtake clients and those along the route. New stakeholders continually evolve during mine life, and the engagement process requires an investor–community–public relations (IR/CR/PR) team to anticipate change and actively scan perception and chatter.Successful communication is more than delivering a message; it is about engaging stakeholders and confirming the feedback loop to ensure the correct message is communicated and the relationship is strengthened.The nature of the mining company’s branding and the public’s perception of company intentions will dictate whether there is willingness to allow the company to follow its desired path. This in turn controls the company’s most scarce resource – time. Timing is fundamental to achieving targeted outcomes with minimal cost and delays, marketing in a peak cycle and acquiring critical capital for development and growth.Branding and stakeholder engagement effectively controls and extends to the company its social licence to operate.CITATION:Goodz, M D and Lonsdale, R M, 2016. Stakeholder engagement – who are you, what do you stand for and why? In Proceedings International Mine Management Conference, pp 239-248 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Jun 22, 2016

By P Cesare, S Munro, D Wandel, R A. Bearman

Consideration of the processing plant operational envelope is a key factor in production scheduling,and therefore mine planning, for any mining operation. In many cases hard-wired or regressionbased tonnage-grade-recovery relationships are used as mine planning constraints and as a means of valuing the system output. In extensions of this type of approach, various regressions can be used to describe throughput limits, based on a number of global metallurgical parameters.The ultimate position for the optimisation of a mine plan and production schedule is to have a full process plant model running as an integrated part of the mine planning exercise. A plant model suitable for this needs to have all the required sensitivities to input parameters such asfragmentation, grade, mineralogy, strength and hardness. The model then needs to convert these to performance measures for the plant, which include recovery, throughput, product size distributions, energy consumption, water use and operating cost.In this paper an approach is outlined that takes this view and then goes beyond it to provide a full, time-based bottleneck identifi cation and valuation tool.Using such an approach it becomes possible to run mine plans and production schedules in windows of days, weeks, months and over the life-of-mine with a time-enabled process model acting as the active constraint. In this way virtual bottlenecks can be identifi ed for various mine plans and schedules well ahead of time. The value of de-bottlenecking can be defi ned, not just at a plant scale, but in terms of the overall mining operation, and the data can be used as the basis for capital investment decisions.CITATION:Bearman, R A, Cesare, P, Munro, S and Wandel, D, 2014. Incorporation of a full process plant model as an active constraint for mine planning and production scheduling, in Proceedings Orebody Modelling and Strategic Mine Planning Symposium 2014 , pp 121–128 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 24, 2014

By R Ayothiraman

Tunnel excavation may induce adverse effects on nearby existing structures/foundations in urban areas. Accurate prediction of tunnelling effects on pile foundations of nearby structures in the urban environment poses a major challenge during design. Several studies have been undertaken to understand the mechanisms of the soil-tunnel-pile interaction, which focused only on influence of tunnelling on nearby existing building and foundations. However, effect of pile loading on existing tunnels did not receive enough research attention so far. So it is essential to measure the response of existing tunnel-lining due to loading on newly constructed pile to assess to the safety against the additional forces/moment caused by pile loading and to evaluate the critical distance for the proposed construction of any structures from the tunnel location. This paper presents result of three-dimensional (3D) finite element analysis carried out in ABAQUS to investigate the effects of pile loading on existing tunnels embedded in cohesive soil. It is found that the effects on tunnel lining depend on horizontal separation distance between pile and tunnel as well as location/elevation of pile tip with respect to tunnel location.

Mar 8, 2011

By Else D

While the underground mining work environment may have processes and equipment considered unique, most of the broad issues likely to affect the occupational health and safety of employees are not. One such occupational health and safety issue that is common to the mining sector and most other industries is noise. Noise as an occupational health and safety issue is of national significance. Presently noise induced hearing loss costs Australia around $35 million per year on compensation claims experience alone. Noisy equipment and work environments are still being tolerated in parts of the mining industry as `part of the job'. Where work has been undertaken in noise management, considerable emphasis has been placed on either industrial hygiene monitoring programs or the provision of hearing protectors to miners working on or around noisy equipment.Opportunities for more cost-effective and long term methods for controlling noise exist. Ready to apply solutions to noise problems in the mining industry are available, but for many mining operators this information is often difficult to obtain. To overcome this problem, the SHARE program collects and distributes solutions to occupational health and safety problems. The program aims to help organisations to close the gap between what is known about solving health and safety problems and what is actually being applied at the shop floor level: Recent developments have incorporated the SHARE program concept into worksite hazard management projects that involve the participation of employee representatives, front line supervisors and engineering personnel. Besides providing workforce members with an increased understanding of hazard management skills, the SHARE in-house program results in the implementation and sharing of solutions to health and safety problems by the program participants.

Jan 1, 1992

By M Davis

Increasing growth in the minerals industry over the past decade has raised the question of whether the standard of training for new geologists has been negatively impacted. This hypothesis was tested by means of a survey. Factors considered included the quality of training and whether it has changed over the past 50 years, preferred styles of training compared to styles of training received and whether the quality of training provided by a company changed with the type or size of company. Data from 435 survey respondents showed a consistent standard of training, but a significant increase in the level of responsibility allocated to new geologists. Those with increased responsibility also had reduced access to additional support and were often asked to perform tasks for which they had little or no training. New geologists were more likely to receive better quality training in a large company (over 100 employees) that owned the mine or exploration lease. A more structured training program was more likely to provide a higher quality result than those with minimal or no structure.

Aug 22, 2011

By J Zhou

This paper discusses the implementation of a mixed integer linear programming model for a coal preparation plant. The plant considered consists of primary and secondary heavy media cyclones, hydrocyclones for intermediate fines and froth flotation for the very fine material. The model is designed to optimise the plant settings and product flows to maximise revenues for a given specification for two product outputs. The model can deal with bonus/penalty aspects of the product pricing for products that exceed or fail to meet specification. We report on a model with two separate coal feeds with parallel circuits for the oversize, intermediate and fines streams. The genesis of this model is more than 30 years old but recent improvements in mixed integer programming solvers make a full mixed integer formulation practical. The original model began as an enumeration of cut points with arbitrary rules for product allocation. The product allocation was improved in a linear programming formulation by Gunn (1982) and Sarker (1991 and 1995). Current mixed integer programming capabilities make it possible to replace the enumeration aspects and solve directly as a mixed integer programming problem. The current implementation uses a general purpose modelling language to formulate the model. Open source and commercial mixed integer programming solvers are compared

Sep 26, 2011

By P Yß±ez, G Ferguson

The El Teniente mine produces more than 340 000 tonnes of fine copper per year from an industrial complex of underground mine, concentrator and smelter. Mass caving methods are employed to deliver approximately 95 000 tpd of ore to the mill, from a number of sectors underground, each sector being in effect a large-scale mine in its own right. This mining activity has faced challenges over the course of the last century such as:the capacity of the underground mine has been expanded to maintain and increase output of fine copper; the increasing size of the ore fragmentation forced to change the mining method to achieve the high productivity and profitability required in the business; and to modify the mining methods to continue mining at depth with safety. Fundamental activities in these mining methods, for the successful initiation of caving and subsequent draw, are:undercutting the base of the block or panel by blasting; and excavating of drawbells. The undercutting design evolves mainly on the height of the blasting to manage the change on ore fragmentation. The methodology move away from incorporating massive areas, typical of the block caving method, to a continuos blasting, typical of the panel caving method. Drawbell design changes on geometry, dimensions and sequence of excavation to deal with a corse ore fragmentation and the resolution of mining difficulties in the form of major rock bursts and collapses of production facilities. This paper focuses upon the evolution of the undercutting and drawbell design used at El Teniente mine and techniques under consideration to deal with future caving operations to provide the bulk of the daily production for the foreseeable future.

Jan 1, 2000

By J W. Glatthaar, M Mavotoi

The occurrence of fluorine in the copper/gold concentrates produced by Ok Tedi Mining Limited has provided a series of challenges to metallurgists since 1988. Although fluorine is distributed throughout the gangue minerals contained within Ok Tedi ores, itsÆ presence in talc and phlogopite (naturally floating fluorosilicates) has proven to be the predominate sources of fluorine in the final concentrate. Initial treatment for the fluorosilicates consisted of the use of a carboxy-methyl cellulose depressant added to the flotation cleaners. This was superceded in 1998 with the installation of a fluorine reverse flotation process for the removal of naturally floating fluorosilicates from the final concentrate when the fluorine content of the final concentrate exceeds smelter-defined trigger points. The fluorine reverse process is similar to by-product molybdenite concentrate production in that sodium hydrosulfide is used to depress copper/gold flotation whilst allowing the fluorosilicates to float. The process was installed in two parallel modules (to match the existing grinding/flotation modules at Ok Tedi), each consisting of a closed rougher/cleaner circuit configuration. Both rougher and cleaner cells are Jameson Cells from MIM Process Technologies, with the selection based on both processing characteristics and available construction space. This paper discusses both the nature of fluorine in-, and its removal from-, Ok Tedi copper/gold concentrates.

Jan 1, 2003

By G Clarke

Commissioning of the Cannington processing plant began in October 1997. The nameplate capacity (of 1.55 million tonnes of ore per annum) was achieved relatively quickly. Since then (like many mines) the operation has strived to increase throughput and improve valuable metal recoveries, to offset declining head grades and lift the value of the operation. The processing plant now has the capability of treating over 3.2 million tonnes of ore per annum and in financial year 2005/06 the combined concentrate production exceeded 600 000 wet tonnes, approximately 80 per cent above concentrate output in the first full year of operation (at the design feed rate). This improved performance was achieved by making changes and additions to each of the major unit processes û primary grinding, flotation, leaching, filtering and paste fill preparation. The changes have included: adding a fines flotation circuit, expanding the grinding circuit, adding a pebble crusher, switching from continuous to batch leaching, building paste conveyors and decommissioning the column flotation cleaning circuits. This paper reviews these changes, outlines the current operating practices and discusses the challenges or opportunities that remain.

Jan 1, 2007

By B Stewart

The SRS-1200 concept came about following the recommendations from the Board of Inquiry into the 1994 Moura No 2 mine disaster with the aim of having a system to remove personnel from an unsafe environment underground via a shaft where no other means of escape is possible. It is a mobile rescue unit that utilises a winding system to operate a man cage. It can descend the cage up to 1200 m into a vertical shaft. This operation is managed from the winder control compartment located on the non-driver side at the rear of the vehicle.

May 5, 2022

By Omnes G

Sixty Schlumberger electrical soundings were carried out in the Depot Springs area, near Agnew, Western Australia as part of an investigation into the availability of groundwater for the Agnew nickel project. The object of the survey was to locate calcrete aquifers related to Tertiary drainage channels on the Pre- Cambrian surface. The electrical soundings were initially interpreted using sets of master curves and auxiliary point methods. Electrical sections were produced and contour maps prepared of apparent resistivity for AB=80m, total conductance of the overburden and transverse resistance.

Jan 1, 1975

By J Cook, S Pike, D Pridmore

"An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation. The application of high-resolution seismic reflection to map structure and/or mineralisation in hard rock environments has progressed significantly in the last decade. Improvements in equipment, field practice, processing and understanding has seen the seismic reflection technique emerge as a cost-effective tool for high-resolution three-dimensional structural and lithology mapping to depths far greater and with superior accuracy than other more conventional geophysical techniques.This paper outlines results and preliminary interpretation of 2D and 3D seismic reflection surveys aimed at defining fault zones and locations for quartz load development in favourable host lithologies at the Cracow low-sulfidation epithermal gold system in Queensland, Australia.As this is possibly the first time that high-resolution seismic reflection data has been used to define the structurally-controlled location of low-sulfidation epithermal gold mineralisation, an important aspect of this work was the derisking or due diligence steps taken prior to commissioning the full 3D surveys at each site. This included full wave sonic logging, vertical seismic profiling and trial 2D lines. Interpretation of the 2D profiles and the drilling of interpreted structure provided the confidence to proceed with the full 3D survey.The advantage of collecting 3D data extends beyond ensuring that the received reflections are located correctly in 3D space. The final 3D data cube can potentially map the entire fault network, thus highlighting flexures and changes in orientation of the structures both vertically and along strike, which is an important aspect in the deposition of gold and for direct targeting.CITATION:Smith, R, Cook, J, Pike, S and Pridmore, D, 2015. Application of high-resolution seismic reflection surveys to exploration for blind vein systems at the Cracow low-sulfidation epithermal field, in Proceedings PACRIM 2015 Congress, pp 77–84 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 18, 2015

By Szymanski J

Although efforts towards producing a `total quality rockfill product' have allowed cemented rockfill costs to be reduced considerably, there is still tremendous potential for further cost reductions. Cemented rockfill costs range from approximately $7 to $12 (US) per tonne of fill placed. Approximately 50 per cent of the rockfill costs are associated with cement costs. A large portion of the remaining 50 per cent is associated with labour and materials handling costs. Several Canadian underground mines utilise haulage trucks and/or conventional belt conveyors to distribute the rockfill. However, due to the restrictive nature of the underground environment, these current materials handling systems have limitations (ie spillage from trucks, dust from conveyors). The Sicon conveyor system (developed in Sweden) has considerable potential for replacing these current methods. The Sicon conveyor utilises a revolutionary approach - the conveyor belt is folded over upon itself (forming a tear drop shape) so that the transported material is completely encased within the belt. The Sicon conveyor's ability to negotiate very tight comers (without transfer points) makes the conveyor very appealing for underground mining applications. An analysis comparing the pros and cons associated with the Sicon conveyor system versus conventional materials handling systems will be presented in this paper.

Jan 1, 1995

By Cripps-Clark CJ

Sulphur partition between metal and slag has been examined on a cast-by-cast basis for BTIP furnaces. Partition values. were calculated from thermodynamic equilibrium data together with oxygen activities computed from the manganese partition. The S-C interaction coefficient, esc , was treated as an adjust- able parameter and the agreement between calculated and measured S partition values optimized. In the case of furnaces operating with low viscosity slags this procedure led to estimates of esc in close agreement with previously measured values. The same analysis applied to daily average data for several Kawasaki Steel furnaces led to the same esti- mates of e c s , indicating a similar approach to equilibrium. Silicon partition between metal and slag has been examined on a time average basis and found to be far removed from thermodynamic equilibrium for most Australian furnaces. A study of Japanese furnaces of comparable size reveals a temperature dependence of Si parti- tion which appears to be close to equilibrium. Australian furnaces approach this behaviour only when operating with low viscosity slags. A preliminary examination of the effects of burdening with TiO 2 on the silicon partition is also reported.

Jan 1, 1980

By J Simpson, M Johnston

Recently Mount Isa Mines undertook a study to review the lead-zinc orebodies to extent of resource and reserves and determine the new life-of-mine schedule, as the Mount Isa and Hilton orebodies had not be reviewed for many years. Also, the recovered value of the Mount Isa, Hilton and George Fisher orebodies had been increased by major performance improvements in the lead-zinc concentrator. The Mount Isa Lead-Zinc concentrator processes fine-grained lead-zinc ore from the Mount Isa, Hilton and George Fisher orebodies. These orebodies have varying levels of pyrite and large variation in the grain size and texture of the galena, sphalerite and pyrite. This variation has a large effect on the recovery of the lead and zinc in the concentrator. Some ores achieve 90 per cent recovery at target grades, yet other ores are unable to achieve æsaleableÆ concentrate grade, with no metal being recovered to concentrate and therefore effectively losing the contained metal to the final tailings. Models were created to predict the metallurgical performance of these orebodies, to better reflect the variation that occurs. These improved metallurgical models and economic data allowed the determination of the Net Smelter Return (NSR) for each block in the geological block model. This NSR is the return to MIM of the metals contained in concentrate. The NSR was used as the cut-off grade criteria when determining the value of the ore. This formed the basis of the lead-zinc life-of-mine schedule and the optimisation of the lead-zinc business.

Jan 1, 2003

Societal expectations about how the industry operates and treats its people will be a key driver in the development of the Australian mining industry over the next 20 - 30 years (Moffat, Mason and Littleboy, 2009). Understanding these expectations will be critical in maintaining what much of the minerals industry calls its 'social licence to operate', or its public acceptance or approval. Yet what constitutes this social licence is poorly articulated, with little published research exploring the concept at a local operational level or at the national level in Australia or internationally. This research aimed to explore the societal expectations of the mining industry in Australia and test a participatory methodology to articulate them. Three workshops were conducted with a sample of 24 members of the 'Australian voting public' to explore community objectives for the onshore exploration and mining industry, and the underlying expectations for how the industry should operate in the future. Qualitative analysis of this data revealed three overarching objectives for the onshore mining industry held by participants. They thought that the industry should: advance Australia's national interests (including social well-being); minimise environmental impact, and; act in a socially responsible manner. Within each of these three key themes, or objectives, a number of tensions were evident in the views of participants regarding the trade-offs they are willing to make to secure economic benefit from mining, as well as the basic conditions for socially acceptable mining. These data provide an insight into the conditions for a national social licence in Australia for the mining industry, and the means for its realisation.

Jun 1, 2010

By A T. Spathis, K E. Leslie, K R. Blay

Many open pit mining operations seek to control blasting-related movement of ore and waste to minimise loss and dilution. Tracking the movement of ore boundaries can result in the maximisation of ore recovery and minimisation of waste sent to the mill, thereby optimising the economic performance of the operation.A novel solution for tracking the ore–waste boundary location before and after a blast uses subsurface markers placed along the boundary with all measurements and scans conducted remotely from the blast block. Upon system activation, user-operated equipment on the surface determines the three-dimensional (3D) location of the subsurface markers.The patented system concept combines two electromagnetic mechanisms, magnetic positioning and radio frequency through-rock communications to enable remote battery-powered markers, buried within the rock to be accurately located in 3D space.Field trials at a quarry have demonstrated the system can comfortably handle over 100 subsurface markers with a complete scan, including set-up, taking less than an hour. Location accuracy for each marker in 3D space is better than 0.5 m at a range up to 50 m from the magnetic source, and the system has an overall operational range in excess of 75 m.CITATION:Blay, K R, Spathis, A T and Leslie, K E, 2015. A remote, rapid and accurate three-dimensional ore waste boundary tracking system, in Proceedings 11th International Symposium on Rock Fragmentation by Blasting, pp 297–306 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 24, 2015

The application of reinforcement techniques to enhance the stability of underground coal mine roadways subject to high stresses is discussed. Research conducted in the Illawarra Coal Measures has been aimed to delineate the factors which influence the behaviour of rock above roadways and the performance of the reinforcement placed. Design considerations for the reinforcement of mine roadways in the Bulli coal are based on a quantification of the rock response together with a reinforcement strategy to enhance the structural integrity of the roof strata.

Jan 1, 1986