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By Z U Bajwah

During the Palaeoproterozoic, a large number of granitic intrusions were emplaced in the various parts of the Pine Creek Geosyncline (PCG). In the central region, the granitic magmatism is represented either by the coalesced mass, eg the Cullen Batholith, or individual plutons such as the Mount Bundey Granite which together with the Mount Goyder Syenite intrude the metasedimentary strata, causing wide spread contact aureoles. Some of these granitic intrusions are temporally and genetically related to gold (and less commonly base-metals) mineralisation present in the adjacent metasediments. These plutons are characterised by the presence of biotite and homblende which appear late in the paragenetic sequence. Electron microprobe analyses of biotite and homblende show that these minerals are poorly to moderately zoned. Biotites are characterised by a decrease in Fe/(Fe + Mg) ratios when plotted against AIVI. Similarly a modest decrease in Ti from centre to the margins of the biotite crystals has also been observed. Furthermore, an increase in Mg/(Mg + EFe) ratios from centre to the margins as well as in mafic to felsic rocks is also apparent. On the other hand, homblendes from the granitic bodies display less well marked trends and are poorly zoned. However, they show systematic increases in Mg/(Mg + EFe) ratios, and decreases in Fe, Al"' and Fe/(Fe + Mg) ratios, when plotted against Si. Magnetic susceptibility measurements on powdered samples of the plutons give results characterised by high values ranging from 0.8 x 10-4 to 2.0 x 10-3 emu/g which place the granites in magnetite- series field. This indicates that the oxidation state of the magma was high during crystallisation. The range of chemical compositions of the mafic phases indicates a rise in the oxidation state of the magma as it progressively became saturated in H20-volatiles and other metals, not partitioned into the earlier crystallised phases in the final stages of magma consolidation. These variations in chemical compositions also indicate that initially fOz was high and became progressively higher during fractional crystallisation of magmas; this subsequently led to the emanation of hydrothermal fluids responsible for the mineralisation in the adjacent metasediments.

Jan 1, 1994

By M Yvon, S Parkes, K P. Galvin, P Wang

Mineral liberation is critical to maximise the grade and recovery of nickel, however this objective is challenged considerably by the poor flotation kinetics, especially that of ultrafine particles (Kelebek and Tukel, 2018; Multani and Waters, 2019). High recoveries demand long cell residence times and hence a large flotation capital expenditure (Wills and Finch, 2016). However, this leads to excessive entrainment of gangue minerals, thus negating efforts to depress its recovery. This study aimed to investigate new hydrodynamic approaches to improve nickel flotation, focusing primarily on unrecovered nickel from a Western Australian tailings stream. Mechanical cell flotation experiments were conducted to understand the flotation kinetics, covering different size ranges. A novel Reflux Flotation Cell (RFC) was also used to improve the nickel recovery and reject the silicates. Future work aimed at applying the RFC to different size portions is also outlined.

Aug 24, 2022

By M Robertson

3D photogrammetry is a powerful tool for data capture and interpretation, utilised at all Australian underground MMG sites. In personnel constrained mines, 3D photogrammetry can free up personnel time, improve data quality for resource modelling, as well as benefit other mining departments.At Rosebery one of the challenges faced by geologists was no longer data capture but, rather, avoiding paralysis by analysis from the sheer abundance of information currently available to the department. Although the data had been interpreted, the structural model was cluttered; the geological block model was not incorporating any geological domains captured by 3D photogrammetry, nor was it being utilised by other departments such as geotechnical engineering.The geology department is now focusing on utilising all the interpreted data gained from each photograph heading into an uncluttered, easily understandable model for geologists and other mining departments.Our solutions involve integrating the Leapfrog modelling suite into the process, streamlining the structural model, tailoring the data interpretations for future updates of the block model and training other departments to improve utilisation of the interpreted data. This process also uncovered other benefits for near-mine exploration, and improving our understanding of the deposit’s origin.CITATION:Robertson, M, 2017. The practical use of underground 3D photogrammetry data at MMG Rosebery polymetallic mine, Tasmania, Australia, in Proceedings Tenth International Mining Geology Conference 2017, pp 409–412 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 20, 2017

Drilling underground can be a hazardous undertaking in many circumstances. Raiseboring and boxhole boring underground could form an integral part of the block caving production methodology and getting the right mix of technical capability, ergonomics and economical viability has been the goal of many machine manufacturers. With the introduction of the Terratec Universal Boring Machine concept, flexibility of raiseboring, downreaming and boxholing has been enhanced by the introduction of a single machine that will perform all three processes. In addition to its technical flexibility, additional safety features have been introduced that will eliminate many sources of injury by mechanising most of the operational procedures. Together with the one-man remote operation, this machine design addresses and solves many of the safety issues. This paper outlines the machine concept, details its safety features and shows the techno-economic advantages for use in the block caving environment. Block caving is a distinct caving method applied mostly to large massive orebodies because of the inherent low costs and high production capabilities. Areas of sufficient size are mined by undercutting so that the mass above will cave naturally. Extraction of the caved ore at the bottom of the ore column causes the caving action to continue upward until all of the ore above the undercut level is broken into sizes suitable for handling (Figure 1).

Jan 1, 2000

By J Whittle

This paper describes what is involved in carrying out a comprehensive optimisation of a long-term operating schedule for a mining complex. It details the data that must be assembled and discusses the different approaches to optimisation and what limitations they put on the variables and constraints that can be handled.CITATION:Whittle, J, 2014. Not for the faint-hearted, in Proceedings Orebody Modelling and Strategic Mine Planning Symposium 2014 , pp 3–6 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 24, 2014

Mobile mining equipment presents only a small portion (ten per cent mining project costs but the selected technology will determine to a large extent the mining performance and mine profitability. The actual performance of the selected mobile equipment technology will rely on the support functions, infrastructure, user interface and user acceptance. Optimising the technology to match the circumstances is an increasingly important phase in a mine feasibility study. Smartly done feasibility studies include the possible future needs of changing or building-up of the selected technology. In massive mining applications the machinery faces quite different challenges than in selective or small-scale mining applications. In massive mining applications the efficient and continuous move of large amounts of material has led to the use of increasing degree of automation. This higher degree of automation in a mining application, on the other hand, will be best applied to a smooth and streamlined mining process and operation. Mining methods like block caving support automated operation. Automated mobile equipment needs supportive infrastructure, monitoring and information transfer systems as well as well established working procedures. Too often the user interface and human factor is disregarded during the consideration of automation. Through the available supplier programming tools it is possible to see how much the selected technology provides flexibility in changing production or economical situations, when major rebuilds or replacements are necessary, and view the effects of all these on the mine economy. When adequate technology is available from various sources, the difference becomes from preparing for the future, managing costs and combining the best layout with the most suitable technological solutions.

Jan 1, 2000

By P Valenzuela

Joint mapping is a fundamental input for rock mass characterisation and slope stability analysis. The usual way to do it is using a compass in the field or digitising structures on a screen, with a software package.In this paper a method to identify and map joints automatically along a rock face is presented; it is called the Concentric Shells (CS) algorithm. The method scans a point cloud sequentially, tests if selected points are ‘true pivots’ within an inner shell, and then it searches for points inside a wider sphere (outer shell).The algorithm, developed by the author, was applied in real data. It reproduces the main features obtained from conventional (compass) and digital mapping (software package). Execution times are approximately 45 seconds for two point sets holding of 3.1 million points. Obtaining the same results via digital mapping takes approximately 3–4 working days.Key advantages of this method are: significant time reductions; elimination of mapping bias; and the ability to manage very large data sets (>2 million points) without the need of scanning the cloud on the screen. These advantages make this method an attractive tool for engineers and geologists wanting to increase productivity.CITATION:Valenzuela, P, 2017. Automated joint mapping using the concentric shells algorithm, in Proceedings Tenth International Mining Geology Conference 2017, pp 257–262 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 20, 2017

By X T. Nguyen

Western AustraliaÆs Mining Act 1978 was amended in 2010 to provide for the requirement of a mine closure plan to be submitted to the Department of Mines and Petroleum (DMP) for approval, as part of a mining proposal application. The mine closure plan must be prepared in accordance with approved guidelines. Guidelines for mine closure plans were developed to assist the mining industry in Western Australia to plan and implement effective closure of mines. The guidelines focus on the application of integrated mine closure principles and industry best practice information on mine closure. This, includes stakeholder consultation, risk based approach, data collection and monitoring, development of completion criteria and financial provision.Due to the potential high level of public interest in the guidelines, extensive consultation with stakeholders was conducted. The purpose of this paper is to share experiences from the consultation process.CITATION:Nguyen, X T, 2012. Mine closure guidelines for Western Australia and consultation process, in Proceedings Life-of-Mine 2012 , pp 43-46 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 10, 2012

By P York

The study commenced in October 2012, to understand the basic ecology of the spotted-tailed quoll (Dasyurus maculatus) and to confirm whether the species utilise previously mined land on the Mt Owen mine site that was rehabilitated in 1996 to 2011, as part of their home range. The spotted-tailed quoll is a widely distributed marsupial carnivore that is listed as rare or threatened in every state in which it occurs. The species is a forest-dependent marsupial carnivore that occupies a wide range of habitat types (Long and Nelson, 2004).The first part of the study involved trapping a spotted-tailed quoll and fitting the individual with a combined global positioning system / ultra high frequency (GPS/UHF) radio-transmitter collar (Telemetry Solution – Quantum 4000E). The benefit of the GPS/UHF collar is that it records locations (or fixes) at intervals programmed by the user. The UHF component allows the researcher to locate the individual at a frequent interval, and the Quantum 4000E also has a remote download function, enabling the GPS data stored in the collar to be wirelessly transmitted between the collar and researcher. The benefit of this new technology is that the animal does not need to be repeatedly captured to retrieve the GPS data.Daytime searches are also undertaken using the UHF receiver to locate the individual and locations of daytime denning and latrine sites. The location of each den site is recorded using a hand-held GPS. Data downloaded from the GPS collar is then imported and mapped using computer software program ARCGIS (geographic information system), to overlay the data points onto aerial photography.Results demonstrate that threatened species will utilise rehabilitation areas post mining. The data presented will be used to develop a greater understanding of threatened species ecology in and around rehabilitated areas, which will assist in the planning and design of native forest rehabilitation areas.CITATION:York, P, 2014. Mt Owen Mine spotted-tailed quoll study, in Proceedings Life-of-Mine 2014 , pp 591–596 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 16, 2014

By F F. Pitard

Observation from attending many conferences around the world reveals that many people are constantly shifting from the word ‘error’ to the word ‘uncertainty’ without a clear vision of what the subtle difference is. The same applies to a large swath of the scientific literature, in which these two concepts are unfortunately often used synonymously, which is a scientific flaw of the first order. In practice, as demonstrated in the Theory of Sampling (TOS), there are both sampling errors and sampling uncertainties. Sampling errors can easily be preventively minimised, while sampling uncertainty for a preselected sampling protocol is inevitable. P M Gy’s work, supported by G Matheron’s critical reviews, demonstrates beyond any possible doubt that sampling uncertainty cannot be achieved if sampling errors are not preventively minimised by applying very stringent rules that are too often ignored by sampling practitioners. A clarification, in line with the TOS, is presented to mitigate the confusion created by circles favouring the use of uncertainty versus the use of the word error. Both words are very different in nature and scope and they are both necessary in their due place and time.CITATION:Pitard, F F, 2017. From errors to uncertainty – a clarification for proper use by the Theory of Sampling, in Proceedings Eighth World Conference on Sampling and Blending , pp 355–358 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2017

By M J. Pejovic, I Miljanovic, A Milutinovic4, T Benovic, A Petrovski

The paper presents a model of a multigrade monitoring-management structure for support to decision making and management in real and extended time in mineral processing (MP). The model was created as a result of a long-lasting research, design and development of mining, computer integrated monitoring-management systems. Apart from the general explanations, the authorsÆ state in the introduction that efficiency of a system for support to decision-making and management in mineral processing is more difficult to achieve by conventional approaches, than by the fuzzy logic approach. Starting from the multiphase structure of process flows in MP, the following are process and monitoring-management oriented graphs. The graphs served as a foundation of the multigrade hierarchical fuzzy model for support to decision making and management in MP. Following the example of the monitoring-management system of the æRudnikÆ mine flotation plant, fuzzy logic implementation was shown. The key conclusions of the paper are that fuzzyfication of layers of the decision making and management model has full justification due to the complexity and dynamics of mineral processing processes, complications and often insurmountable difficulties concerning the precise description of real systems by conventional mathematical tools, variability of external influences, and the (general) non-linearity of the MP processes management criteria functions.

Sep 26, 2011

By I T. Ross

Sampling drawpoints in block cave mines has been a contentious issue for many years. Doubts have been expressed as to the validity of the process used at most mines. This paper outlines the sampling practice commonly in use, discusses the resulting issues associated with reconciliation and drawpoint closure decisions. The paper also looks to the future and highlights issues for some block cave mining operations currently planned to have in the order of one thousand active drawpoints. It is likely that these operations will require a new approach to drawpoint sampling. There are several potential technologies currently available although some appear to be better suited than others to replace the current approaches. CITATION:Ross, I T, 2012. Sampling in block cave mines, in Proceedings Sampling 2012 , pp 81-86 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 21, 2012

By B Wentzinger

This paper presents the results of state parameter estimates in an active coal boiler ash storage facility using the most recent methods currently in use for cone penetrometer interpretation. State parameters estimates are also compared with the critical yield stress ratio approach, which is proposed as an additional liquefaction potential screening method. Recommendations are provided regarding additional in situ tests and laboratory tests that may be undertaken to improve the state parameter assessment and data produced for use in subsequent stability or liquefaction studies.

Jul 1, 2021

By P Micale

Geological data provides the foundations for the mining value chain. It is used to underpin the modelling and planning and consequently optimise downstream business decisions. However, it is often forgotten or taken for granted. End users often assume the data to be sound without verification. Geological data can be considered a company’s number one asset. Subsequently, the storage, use and management of this data need careful curation and time invested in preserving and protecting it. An established polymetallic mine with 20 000 drill holes could have a data replacement value in excess of $500M at 2020 prices, excluding labour and salary costs. The Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore Reserves (the ‘JORC Code’) provides guidelines for Public Reporting. Within the code, Table 1 requires discussion around the different types of geological data, its collection and use. What is needed is additional details regarding the validation and integrity of the geological database. A comprehensive guideline specifying minimum geological standards for geological databases has been developed. This expands on the critical points outlined in Table 1 of the JORC Code. This guideline can be used by companies where geological databases are managed in-house or used to assess these services’ outsourcing. This guideline will ensure that geological data is reliable and unadulterated and can be used with confidence. Using this guideline will assist in preserving the investment of geological data in the mining value chain

Mar 22, 2022

By A Whaanga

The use of photogrammetry has greatly increased the accuracy of 3D mapping underground. However, this has not reduced the need or desire for geologists to produce plans and sections showing an interpretation of the mapped geology. At the Waihi Underground Gold Mine, a hybrid solution has been developed that utilises the accuracy of photogrammetry and mapping onto face photos with the CAD-based Deswik.MappingTM functions to create plan and section maps. These have the benefit of looking like traditional paper maps but are more spatially accurate and richly attributed with metadata that can be filtered and exported to downstream processes. Deswik.MappingTM is a tablet-based solution that allows the geologist to map digitally with a stylus. Automation is utilised for the updating of survey as-builts, approved designs, drill holes, geological mapping, vein interpretations and mine work areas, reducing the requirement to print out maps at various locations and scales. Having 3D mine software on a tablet device provides a wealth of features not available when using paper: scaling is a problem of the past; information can be turned on and off; features can be viewed in 3D; and measurements between points of interest can be calculated in 3D space, for example, between vein wireframes and drill hole sample information. A suite of custom scripts has been developed that take the spatially accurate, registered and attributed polyline data from photogrammetry scans and converts them to a geological mapping legend with vein textures, structural information, and lithological boundaries. These 3D maps can be plotted in plan or section view and satisfy the requirements of the most ardent paper map supporter.

Mar 22, 2022

By T Takayama, M Matsumura, Y Konno

The steel industry accounts for 14 per cent of domestic CO2 emission in Japan, and iron ore sintering process occupies approximately three per cent. While Fe content in iron ore is gradually decreasing. So, the amount of concentrated iron ore will increase in the future. We have focused on magnetite concentrate as sinter materials, because magnetite can be easily magnetically beneficiated. However, it is experienced that blending magnetite ore resulted in increasing Fe2+ component in the iron ore sinter, which results in lower reducibility. Therefore, promoting the oxidation reaction from magnetite to hematite in the sintering process is countermeasure for reducibility. In addition, this promotion causes increase of oxidation heat, which results in high sinter strength and reduction of coke. It is assumed that the oxidation of magnetite tends to proceed in the cooling stage, where the oxygen partial pressure increases after the combustion of fine coke, but there are few studies on the effect of heat profile, especially cooling path. The purpose of this study is to design the effective sintering heat profile to promote oxidation of magnetite ore, especially, to investigate the effect of cooling path on sintered ore microstructure. In this study, magnetite ore and magnetite reagent were respectively mixed with calcium carbonate reagent. Then the mixed samples were pressed and formed into cylindrical tablets for simulating the adhesive layer of a pseudo particle. Through examining influence of maximum temperature and cooking rate on oxidation reaction of magnetite, we confirmed that the oxidation reaction of magnetite is suppressed at above 1350°C for maximum temperature, compared to 1300°C. Sintering at lower temperature is desirable because hematite is stable below 1350°C in the Fe2O3-CaO phase diagram.

Nov 8, 2021

By I R. Souza

At the mining industry, there are several uncertainties that may affect the mobile mining equipment fleet sizing and usage, such as commodity supply and demand, which impacts the mineral price, environmental licenses to allow operations and strategic decisions made by the own mining company. Due to that, it may happen to acquire a mobile mining equipment for a specific site and before it finishes the entire forecasted life cycle, the machine gets idle on that operation and a decision must be made regarding this matter. On large mining companies with several sites, equipment transfer provides a good solution to solve this issue and at the same time it provides operational flexibility and allows to use the equipment until the initially planned working hours. This article presents a method to compare technically and financially whether it’s more feasible to transfer a used equipment or to buy a new one. In other words, we will compare a brand-new machine versus a used one in terms of safety, net present value (NPV) considering both capital expenditures (CAPEX) and operational expenditures (OPEX), technological obsolescence, risks, equipment maintenance reliability and lead times. Although it’s not the main purpose of the paper, it will also be briefly discussed the importance of having a considerable amount of backup equipment to handle low likelihood and high consequence risks that may materialise. This backup equipment portfolio is particularly important to avoid loss of sales and profits in case the production plan changes and it demands further equipment than initially planned to cope with the forecasted production.

Nov 8, 2021

By M Pomery

BHP’s Western Australian Iron Ore Operations (WAIO) move approximately 250 million tons of ore per annum. The magnitude of the constant changes to the terrain models along with the diverse output and presentation requirements of numerous stakeholders presents significant challenges for the geospatial team. This paper describes how the WAIO Survey team use a combination of technology and optimised workflows to capture, ingest, publish and access large data sets for diverse stakeholder requirements. Machine learning for processing of data and the use of web based systems to track and prioritise task allocation of resources will be discussed in detail, in addition to the changes to the traditional roles of surveyors from the use of automation and mobile technology.

Sep 18, 2023

By G Reynolds, L Lu

Queensland Pacific Metals (QPM) is developing its flagship Townsville Energy Chemicals Hub (TECH) facility to produce nickel and cobalt sulfates from imported high-grade nickel laterite ore for nickel-cobalt-aluminium and nickel-cobalt-manganese Li-ion batteries. The TECH facility is expected to use a patented leaching, recovery and recycling process called the DNi Process™. It uses the nitric acid leaching process for extracting nickel, cobalt and other valuable metals from laterite ore. Apart from the nickel and cobalt sulfates, the TECH Project will also produce high purity alumina, hematite (~640 ktpa) and other by-products. The hematite by-product precipitated from the DNi Process™ (hematite precipitate hereafter), is high in Fe and particularly low in impurities. QPM is working to identify potential applications for these high-purity by-products to generate additional revenue and to achieve its zero-waste ambition. As such, QPM has engaged CSIRO to evaluate various agglomeration options to produce low-cost, hematitic products suitable as ironmaking feed materials. This paper will first reveal the unique characteristics of the hematite precipitate arising from the TECH Project and then examine the sintering and pelletising processes for preparing the hematite precipitate as an ironmaking feed.

Sep 18, 2023

By G Reynolds, N A. Ware, L Lu

Queensland Pacific Metals (QPM) is progressing its Townsville Energy Chemicals Hub (TECH) project to produce nickel and cobalt sulfates for advanced battery materials. Apart from the nickel and cobalt sulfates, the process also generates a hematite by-product (~640 ktpa). The hematite byproduct precipitated from the process, hereafter ‘hematite precipitate’, is high in Fe and particularly low in impurities. However, it is a fine <20 μm crystalline, hydrometallurgical precipitate and is produced as a filter cake containing a high moisture content of about 15 per cent. This is considerably different from natural hematite ore and is expected to change its performance during sintering. In the present study, laboratory scale sintering tests were undertaken to evaluate the potential impacts of substitution of the hematite precipitate for traditional magnetite concentrates and further for Australian hematite-goethite ores in a simulated industry base blend. Substitution of hematite precipitate for magnetite concentrates was found to slightly increase the sintering temperature required to achieve the strength of laboratory sinters. However, further substitution of hematite precipitate for Australian hematite-goethite ores slightly reduced the sintering temperature required to achieve the laboratory sinter strength. These results reflect the reduction in Al2O3 contents of the blends and are consistent with the trend observed in industry and pilot scale facilities. The reduction in sintering temperature generally correlates to a reduction in fuel rate in the larger scale sintering process. The pore structure of selected laboratory sinters was further examined and discussed in conjunction with sinter strength. The pore structure images highlighted the relative difference between the blends with the most obvious difference being seen at 1290°C which correlates well with the laboratory tumble index (TI). The laboratory sinter samples showed an increase in porosity and irregularity of pore shape, as hematite substitution increased demonstrating the correlation between a more porous structure and a lower TI.

Sep 18, 2023