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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

By R G Warren

Most orebodies have cross-sections of less than 1 km2 and hence do not offer a particularly large target for exploration. Fortunately, although in the geological record ore deposits are small and rare and result from the exceptional coincidence of certain geological processes, these processes are mappable on a much larger, district to regional scale and constitute a mineral system in which the ore deposit is the central feature. A mineral system can therefore be defined as `all geological factors that control the generation and preservation of mineral deposits, and stress the processes that are involved in mobilising ore components from a source, transporting and accumulating them in more concentrated fonn and then preserving them throughout the subsequent geological history'. The mineral system concept emphasises that for many ore deposit types, although economically viable mineralisation may only occur on a scale of say, hundreds of metres, the total system of fluid-rock interactions that led to ore formation can extend over a distance of tens to hundreds of kilometres around the deposit. When mapped out, the total mineral system provides a far larger exploration target than the actual ore deposit itself. Important geological factors defining the characteristics of any mineralising system include: 1. sources of the mineralising fluids and transporting ligands; 2. sources of the metals and other ore components; 3. migration pathway; 4. thermal gradient; 5. energy source; 6. a mechanical and structural focusing mechanism at the trap site; 7. chemical and/or physical traps for ore precipitation. Many of these factors individually are common throughout time and space and are mappable on a regional scale. The delineation and empirical prediction of mineral systems can thus be approached by combining two components of metallogenic research. Firstly, the development of maps of regional geoscientific data and data sets of the distribution of factors significant for mineral systems in general. Secondly, the determination of the essential ingredients of particular styles or types of deposits in terms of mappable elements that any exploration program could focus on.

Jan 1, 1994

By V A. Diemar

The Chatree Gold Project represents a greenfields discovery of metallurgically clean shallow gold mineralisation in a logistically simple terrain. Total Measured, Indicated and Inferred Resources are currently 31 tonnes of gold and 160 tonnes of silver. Gold occurs in an adularia-sericite epithermal system within quartz-calcite-adularia veins, breccias and stockworks. Host rocks are volcanic arc porphyritic latite-trachyte flows, their pyroclastic equivalents and volcaniclastics of upper Permian to upper Triassic age. The mineralisation was deposited in dilated zones during repeated reactivation of pre-existing structures. To-date five mineralised prospects have been defined by drilling with three reaching JORC Code Mineral Resources status. The project is in its definitive feasibility stage and is anticipated to be in construction during 2000.

Jan 1, 1999

By B Banerjee, H Masoumi, X Shen, S Raval, D Tannant

Structural mapping of pit walls can be performed using digital images and photogrammetry software, but the performance is limited by weather and environmental conditions including dust, rain and light. On the other hand, active sensors such as terrestrial laser scanners (TLS) and total stations (TS) suffer from vertical orientation bias and occlusions when persistent discontinuities dip at the same angle as the scanner line-ofsight. The recent development of the compact light detection and ranging (LiDAR) systems has made it possible to mount these sensors on unmanned aerial vehicles (UAVs) or drones which offer the potential to overcome limitations that are inherent in existing mapping systems. This study details the research involving integration and application of an advanced UAV-LiDAR system for structural mapping of a highwall. A state-of-the art laser scanner with an inertial measurement unit (IMU) and real-time kinematic global positioning system (GPS) was integrated on to a UAV. The system was first tested in a laboratory condition. Then the UAV-LiDAR system was employed to map a highwall of a coal mine. The planned flight trajectories tested the system at variable distances from the highwall face and at various speeds. The raw data collected from individual sensors were fused, filtered to remove noise, and segmented to produce a surface scan model. Finally, the point density and surface coverage were measured using the surface scan model of the highwall. The parameters were compared with equivalent measurements computed from a reference TLS data. The study demonstrates the capabilities of a UAV-LiDAR system to generate accurate and occlusion free data for mapping highwall geological structure with very quick and efficient flights in the field. CITATION:Raval, S, Banerjee, B, Shen, X, Masoumi, H and Tannant, D, 2018. Evaluation of a UAV-LiDAR system for mapping geological structures in an open pit highwall, in Proceedings The Fourth Australasian Ground Control in Mining Conference (AusRock), pp 496–503 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 30, 2018

By P Hanna

Following the Busang fiasco, more detailed guidelines were appended to the latest revision of the JORC Code released in September 1999 (JORC, 1999). Although the definitions and terminology essentially remained unchanged, the additional information in the guidelines has highlighted a number of issues for consideration by geologists undertaking computer-based resource estimations. The three main issues are:Data Integrity û details such as drilling and logging techniques, sampling procedures, assay tests, site visits, data recording and aggregation methods need to be considered. Geological Interpretation û is the Competent Person applying the appropriate software interpretation to the deposit in accordance with the regional setting. Are the correct computer-based tools being applied and are they producing the desired result (without compromise) to the satisfaction of the Competent Person? Modelling Technique û the importance of the relevant experience of the Competent Person not only in regard to the geology, but also with respect to the modelling algorithms and resource calculation methods of the computer software system involved. At the end of the day, it is essential that the Competent Person undertake a reality check on the resource estimation itself. They should also check that the borehole spacing is in accordance with the level of continuity for each critical parameter (such as structure, grade, impurities, etc) for which the resources are categorised.

Jan 1, 2000

Transport Canada (Federal Government) constructed the Halifax International Airport (HIA) near Halifax, Nova Scotia, Canada in the late-1950s. Site location criteria were primarily; direct access to the city and a raised flat topography. Unfortunately, the site chosen was located on shallow Meguma group pyritic slate bedrock. In 1982, during the construction of an airport taxiway, it became very apparent that acidic run-off from excavated bedrock at the site was having a negative impact on adjacent aquatic habitat. The ensuing 20 years involved many efforts to rectify the acidic drainage problem with mixed results. Some of the techniques which have been implemented at HIA to address the acid rock drainage (ARD) issue include: dry covers, wet covers, wetlands, electrochemical treatment, open limestone channels, limestone gravel polishing beds, agricultural limestone application, and two hydrated lime [Ca(OH)2] addition treatment plants, the first producing low density sludge and the new one that creates high-density sludge. Based on over 20 years of water quality monitoring data it is apparent that only certain acid drainage mitigation methods have been effective at HIA. In 2000 when the Halifax International Airport Authority (the Authority) took control of the operation and management of the airport, including the ARD issue, it was decided to construct a modern, highdensity sludge, hydrated lime treatment system. This new $CAN 7 million system is now in operation and is achieving compliance with water quality guidelines. Due to high operating cost, a review of methods to optimise the system is being carried out. The HIA ARD problem, though minor by comparison to most mine sites, has provided unique challenges and may provide valuable insights into this urgent environmental and financial issue.

Jan 1, 2003

By I Mason, G Turner, J Hargreaves

One of the key objectives in production from any mine is the minimisation of ore loss and dilution. This can only be achieved when the distribution of ore within the mine is known. The distribution of ore is usually evaluated from a combination of drill hole information and underground mapping data. Three-dimensional models of the ore distribution are then constructed by interpolating grades, contact locations and confirming these estimates through mapping. While the interpolation procedure can incorporate an understanding of the local geological conditions, it is an approximation and thus susceptible to some degree of ore loss or dilution. Naturally, such problems increase in areas of sparse geologic information or greater geologic complexity. Borehole radar offers an approach to decrease the interpolative aspects of modelling by providing a continuous image of some ore contacts. Borehole radar works by building a two-dimensional image of an ore contact from radio waves bounced off the contact from closely spaced positions along a borehole. This image can be imported into Datamine (or a similar design package) and incorporated into geological models of a given ore block. The results of a trial survey from the Mariners nickel mine at Kambalda are presented to illustrate the improved level of detail and accuracy that can be achieved through the incorporation of borehole radar into orebody delineation practice. Once implemented on a large-scale this technique has the potential to greatly increase the cost-effectiveness of long hole stoping at Kambalda, through increased ore recovery and reduced dilution.

Jan 1, 2000

By M Scoble, W S. Dunbar

This paper reviews methods for grade estimation in short-term mine planning for block caving. Two particular tools are used: Ordinary Kriging and Simple Kriging with moving averages. It is also considered the influence of draw characteristics on the grade estimation process. Reference is made to mine case study data and analysis. These demonstrate that operational grade estimation is not a trivial process. It must take into consideration: the grade variability (in terms of ore and dilution), sampling interval, geological and geotechnical characteristics, geometrical layout and draw characteristics. Significant improvements appear possible in short-term planning if variogram analysis, as well as kriging methodologies, are introduced into the operational grade estimation process.

Jan 1, 2000

By C Staak, H Mischo, A Fichtner, F Reuter

In mining and remote areas of resource industry, there has been a development towards lacking emergency medical first aid response, that creates a potential disadvantage for patients after work accidents and other medical emergencies compared to standard population. This raises the question how a professional emergency medical coverage can be provided underground, taking into account lacking medical professionals in small resource companies combined with long rescue times. Aiming on the closure of this gap, a team of the mine rescue brigade from the Research and Training Mine Reiche Zeche (Forschungs-und Lehrbergwerk (FLB) Reiche Zeche) of the TUBAF Technische Universität Bergakademie Freiberg in Freiberg/Germany and its cooperating emergency departments of the Freiberg District Hospital and the Zeisigwaldkliniken Bethanien Chemnitz developed a totally new rescue concept using elements from tactical medicine and advanced emergency medicine combined with a specifically designed compact equipment and a highly standardised teaching curriculum. A fully new standardised and condensed tactical medical approach was developed including specifically adjusted equipment, and was taught in a didactically optimised way within 16 lessons in two days. Objective Structured Practical Examinations (OSPE) using manikins and simulated patients were conducted and compared to the identical exam of the reference group, which consisted of advanced paramedics. The standardised tactical medical scheme includes vital functions and body checks, advanced life support, nasal and intraosseous drug application, supraglottic airway management, artificial ventilation, thoracocentesis, bleeding control including tourniquet, fracture repositioning and splinting, transport bedding and thermal preservation. The developed Tactical Medical Mining Rescue (TMR) concept was subsequently included in the German guidelines for mine rescue services in 2022 and is already implemented in many companies in Germany and several international projects.

Sep 1, 2024

By A P MACONOCHIE

The methods used and some of the results obtained from a major geotechnical study of the Ok Tedi mine area, Papua New Guinea, are described. The study was carried out at both regional and local scales and extended over a two-year period. A team of individual engineers and scientists from a variety of disciplines carried out the work. This study may provide a model for other investigations in similar environments.

Jan 1, 1992

The importance of proper planning, preparation, and execution of a steady state sampling campaign for metallurgical plant assessment must not be underestimated. Careful planning can increase the amount and reliability of information from an optimum number of samples and fully utilize available plant data. It requires specification of the data required, determination of run duration sampling frequency, the selection, modification and testing of sample points and cutters, as well as organisation and briefing of plant and sampling personnel. Preparation immediately prior to sampling, the conduct of the sampling campaign itself and procedures to handle the collected samples and information are discussed. Cutter design, fabrication and use are described in detail, and typical sampling situations, for ball mills, classifiers, pipes, launders, flotation cells and thickeners are considered individually. Measurement of pulp flow rate can often resolve difficult mass balance problems, and discussion of convenient techniques is included.

Jan 1, 1976

By T. Baker

The Eloise Cu-Au deposit is 60 km SE of Cloncurry in NW Queensland and has a current indicated reserve of 3.2 Mt @ 5.8 per cent Cu, 1.5gA Au and I9g/t Ag. It is hosted by metasediments and metabasic rocks that underwent amphibolite facies metamorphism at 550-600¦C and less than 3.5 kb. Peak metamorphism coincided with the regional D2 event which produced an S2 foliation with north-south strike and variable sub-vertical to steep east or west dip. The deposit is associated with several major shear zones parallel to the S2 foliation. The lodes form part of a large alteration system that is localised by the retrograde shear zones. Homblende-biotite-quartz with minor sulphides occur early in the alteration paragenesis which is overprinted by chlorite-muscovite-pyrrhotite-chalcopyrite ¦calcite+¦nagnetite. The later assemblage replaces the earlier Fe-K alteration as well as Fe-rich metamorphic assemblages such as homblende, biotite and staurolite indicating a post peak metamorphism timing for ore formation. Although replacive textures are the most common, the alteration can display open space infill and brecciation as well as durchbewegung and mylonite textures indicating that mineralisation occurred during ongoing ductile deformation. All these features are crosscut by a later brittle phase of calcite-chlorite-quartz¦pyrite alteration.

Jan 1, 1994

The project is undertaken by Elgas Pty Ltd, a 50 per cent joint venture between AGL and BOC, to store 65 000 t of LPG in underground storage at Port Botany, NSW. The contractor, Concrete Constructions Pty Ltd, elected to use drilling and blasting techniques. The project specification called for the following works to be excavated: Access Shaft:122 m (out of 140 m total depth), 6.0 m diameter (selected by the contractor),Operation Shaft:125 m (out of 150 m total depth), 4.0 m diameter,Water Curtain Gallery:500 m (Later extended by additional 270 m), 4.0 m wide and 3.5 m high,Storage Caverns:910 m, 14.0 m wide, 11.0 m high,Top Heading:14.0 m wide, 5.5 m high,Bench:14.0 m wide, 5.5 m high,Connection Galleries:250 m, 5.5 m wide, 5.5 m high.A total of 156 000 cubm of rock to be excavated.

Jan 1, 1999

By N Khalili, J Zhao, G F. Zhao

Toppling failure of a jointed rock slope was studied by using the distinct lattice spring model (DLSM). Compared with the classical discrete element model, the DLSM has the advantages of free calibration of micro-mechanical parameters and easy to represent discontinuities, and is more computationally efficient. In this work, the DLSM was used to investigate the toppling failure of jointed rock slopes. The numerical simulation was verified against experimental data from a centrifuge model test on a jointed rock slope. Both the horizontal deformations and failure pattern observed in the centrifuge test were reasonably reproduced using the DLSM. Then, the mechanism of the flexural toppling failure was studied numerically by using a parameter analysis. Finally, some insights were derived that may be useful for practical engineering.CITATION:Zhao, G F, Khalili, N and Zhao, J, 2014. Application of the distinct lattice spring model on toppling failure of a jointed rock slope, in Proceedings AusRock 2014: Third Australasian Ground Control in Mining Conference , pp 207–214 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 5, 2014

By J Manuel, N Ware

Ideal iron ore sinter is produced by optimising the balance between coarse (+2 mm), stable ore nuclei and a reactive matrix consisting largely of fluxed -1 mm fines. The authors have previously published work evaluating the matrix melting behaviour of a number of fine ores, using techniques developed by CSIRO. The focus of that work was to demonstrate the contribution of the matrix to overall sinter quality, with the results showing a direct correlation between melting point, matrix porosity and strength. CSIRO has also developed a complementary test to study the behaviour of coarse ore nucleus particles in contact with the sinter matrix and provide an evaluation of their reaction and assimilation properties. This test provides valuable fundamental information that can be used to better understand the role of specific ore types and optimise blend composition.The CSIRO laboratory-scale assimilation test is carried out by embedding particles of ores of specific sizes into a fluxed matrix of known sinter blend composition, using real ores and fluxes, in a laboratory test that directly relates to pot-grate and plant sintering conditions. Samples are fired under controlled conditions in a tube furnace using a standard heating profile and a constant, low-oxygen potential atmosphere. These conditions simulate the actual sintering process while removing the effects of the many locally-variable parameters (eg temperature, oxidation potential and localised chemistry) that exist in the actual process, meaning that trends in behaviour can be more clearly seen. Designed as a compromise between the industry-standard pot-grate sintering test and a more fundamental test using chemical reagents, the aim is to isolate and evaluate the nucleus behaviour of an individual blend component to allow an improved understanding of the role that an individual ore plays in a specific blend. Measured cross-sections of the resulting fired samples provide a semi-quantitative measure of reactivity, while accompanying photomicrographs allow a qualitative assessment of assimilation properties (eg volume and distribution of secondary porosity generated during reaction).In this paper, to complement the previous work published on melting behaviour, nucleus particles were selected from hematite, hematite-goethite and goethite ores and embedded in a simulated plant sinter matrix. Drilled core particles of two sizes were tested at fixed temperatures simulating low- (<1300°C) and high-temperature (>1300°C) sintering conditions. The resulting assimilation properties are compared and discussed as a function of particle size, temperature and ore/sinter mineralogy. The implications for the contribution of each component to the prediction of blend sinter quality are also discussed.CITATION:Ware, N and Manuel, J, 2015. Fundamental nucleus assimilation behaviour of hematite- and goethite-containing ores in iron ore sintering, in Proceedings Iron Ore 2015, pp 77–82 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 13, 2015

By S Hapugoda, M Peterson, A Haileslassie, A Poliakov, E Donskoi, L Lu

Most metallic iron in the world is produced in blast furnaces from different feed stocks – sinter, lump ore and pellets. Sinter is the main iron-containing feed to the blast furnace and can constitute up to 70–85 per cent of the total ferrous burden. As sinter quality is a key element for stable blast furnace operation, the textural, chemical and physical characteristics of the sinter are very important. Two major factors that affect sinter strength are mineralogy and porosity. This study utilised optical image analysis (OIA) to characterise sinter mineralogy, and the results were compared to those obtained by manual point counting under the optical microscope.Two major mineral characteristics of iron ore sinter are the presence of primary (unreacted) and secondary (derived from melt) hematite. Standard OIA, which is based on RGB thresholding, is not able to distinguish them as they have the same reflectivity; however, primary and secondary hematite in iron ore sinter have a different morphology. The CSIRO-developed OIA software Mineral4/Recognition4 has a unique feature to identify various textures/morphologies of the same mineral. Together with other capabilities of the Mineral4/Recognition4 software, this feature was used to identify different types of hematite and silico-ferrite of calcium and aluminium and other common sinter phases, such as magnetite, larnite, glass and remnant aluminosilicates.A visual comparison of the sinter mineralogy present in optical photomicrographs and that present in the mineral maps created automatically by the Mineral4 module of the CSIRO software confirmed the accuracy of the automated mineral identification.CITATION:Donskoi, E, Hapugoda, S, Lu, L, Poliakov, A, Peterson, M and Haileslassie, A, 2015. Advances in optical image analysis of iron ore sinter, in Proceedings Iron Ore 2015, pp 543–548 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 13, 2015

By R D ROSENTHAL

BHP Iron Ore Ltd's Mt Whaleback is the largest single open-pit iron ore mine in the Pilbara region of Northwestern Western Australia. A division of BHP Minerals, one of three core businesses of Broken Hill Proprietary Company Ltd (BHP), BHP Iron Ore - Newman is a joint venture with minor participants C Itoh Minerals and Mitsui. Mine planning for Mt Whaleback generates detailed sequence plans for a long term forecast incorporating equipment requirements, marketing forecasts, and pit development strategy. Utilisation of several computer packages, both commercially available and site modified, are necessary to achieve such a demanding task.

Jan 1, 1992

By L Yang, L Chen, E Hu, D Tang

Online monitoring of particles cumulative percent passing (PCPP) for a target size at hydrocyclone overflow, compared with traditional offline methods, provides PCPP feedback in real time, and is advantageous in enabling energy-efficient comminution, increasing downstream flotation efficiency, and improving upstream resource knowledge. However, existing online approaches are generally costly and bespoke, and some are sensitive to operational changes. Therefore, this study proposes a new low-cost alternative based on accelerometer measurement for online PCPP monitoring in the overflow of hydrocyclones and provides a preliminary experimental investigation under dry condition. The proposed method uses a sensing probe inserted into the overflow pipe of a hydrocyclone to receive particle impact from the incoming slurry, with accelerometers attached to the probe and mounting frame outside the pipe for particle-probe impact detection. As a preliminary investigation before studying particle-probe impact events in slurry, tests under dry condition without fluids were conducted using dry sand particles in free fall from a fixed height. Accelerometer measurements are analysed in both time and frequency domains through root-mean-square (RMS) and fast Fourier transform (FFT). Results show that accelerometer measurements are useful in estimating mass flow rates, which are correlated to the accelerometer output amplitude RMS values in time domain, in a non-linear mapping. Different particle size classes can be identified by examining the accelerometer output amplitude at a known mass flow rate. Different particle size classes feature their distinct signature frequencies (SFs) that can be examined via FFT and the SF is found to be independent of the mass flow rate. The results imply that any PCPP changes can be detected by the change in the accelerometer output amplitude as well as a shift in SF, which demonstrates the effectiveness of using accelerometers to gauge changes in PCPP. Based on the current findings in dry condition, future work will investigate particle-probe impact events in slurry.

Aug 24, 2022

By W A. Take, M McKellar, A Walsh, S McDougall, S G. Evans

Recent tailings dam failures have heightened public awareness of the hazard posed by storage facilities for mining waste, illustrating the need for a more critical examination of tailings dam breach mechanisms and the potential mobility of liquefied tailings. Knowledge from tailings dam breach studies will help improve safety and risk management through more accurate inundation maps, dam consequence classifications and emergency preparedness plans. Tailings dams differ from conventional water retaining dams, although dam breach relationships used in practice rely heavily on relationships derived for breach processes from the latter. Physical modelling offers a controlled environment to advance the understanding of tailings dam breach processes, thereby allowing for modelling of simple geometry and boundary conditions to test hypotheses. The performed experiments investigate prototypical tailings dam configurations and material behaviour, with the objective of validating numerical models that will enable practitioners to better assess and mitigate tailings flows resulting from tailings dam failures. Research conducted in the Queen’s University Landslide Flume at the Coastal Engineering Laboratory has investigated the breaching of 1 m high dams with tailings geometry by overtopping initiated by a v-notch incised in the dam crest. This paper presents the initial results of the next stage of this research comparing the outflow hydrograph following loss of containment caused by shear failure to overtopping initiated by notch flow. The two dam experiments presented are constructed with similar dam and reservoir geometries allowing for a direct comparison of the effect on the outflow hydrograph of each failure event. Preliminary outcomes suggest that although both dam failure events are triggered from separate mechanisms their geometries allow for similar values of Q_peak to be reached. Future work is currently planned to expand the shear test series to explore the influence of failure mechanism on the outflow hydrograph.

Jul 1, 2021

By Neville Rockhouse

This paper examines the interrelationship of conducting full risk assessments in the context of the coal mining industry and under the framework of the Health's Safety in Employment Act 1992. In the context of Occupational Health's Safety, Risk Management is a holistic management process that can be used by individuals working in all organisations and from all industries. The Australian New Zealand Standard 4360: 2004 defines a Risk as being; The chance of something happening that will have an impact on objectives. This definition is followed by several notes that include: a risk is often specified in terms of an event or circumstance and the consequences that may flow from it, risk is measured in terms of a combination of the consequences of an event and their likelihood, and risk may have a positive or negative impact. For the purposes of this paper, the above definition will be adopted. This paper examines the newly expanded approach of the fully documented risk management process in the New Zealand coal mining industry. This is done in the context of the coal mining regulations but more importantly by using the framework of the Health & Safety in Employment Act 1992. This legislation under Section 6 requires all employers to, Take all Practicable Steps to prevent harm coming to employees while at work and to others who might be at or in the vicinity of a workplace. When the term 'all practicable steps' is studied, one can clearly see that such steps should be the same steps taken that a prudent and reasonable person would have taken given the same type of circumstance. Due to the fact that in New Zealand parliament made statutes is administered by a Government Department, means that their breaches will be heard before a judge in the District Court. Under the Westminster System of Justice, a basic dictum of that court in matters relating the occupational health and safety is that a breach needs to be satisfied to a specific standard. That standard is, 'Beyond a reasonable Doubt'. One of the primary benefits of adopting a proactive approach to risk management is that if the industry were to adopt similar approaches, then this mythology could be seen as an industry standard. As such, the approach carries the same status in a court of law, as that of an Approved Code of Practice.

Jan 1, 2007