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Models of the genesis of existing ore oodles and targetting of exploration for new mines are greatly enhanced by an-understanding of the plate tectonic environment existing at the time of mineral emplacement. In areas of recent or active tectonism, a study of the present-day crustal and upper mantle structure is an obvious starting point in unravelling the evolution of the accessible upper crust. Bougainville is the northern-most island in the Solomon Islands arc. A 7km deep trench almost 100km off its western coast marks the commencement of subduction of the Solomon Sea plate beneath the Pacific plate. As outlined by the seismicity, the subducted crustal slab under the southern half of Bougainville reaches the axis of the island at about 100km depth, from which point it dips near vertically another 300km into the upper mantle. Large surface blasts at the Bougainville Copper Mine at Panguna, Bougainville, Papua New Guinea were used to derive an unreversed upper crustal profile of the island. The crust appears to be relatively simple, being comprised of a 5km deep layer with a P-wave velocity of 4.5km/sec, overlying a l0km thick layer with a P-wave velocity of 7.2km/sec. Constraints on the 15km mantle depth were provided by the identification of both P to and S to P phase conversions of seismic waves from local shallow earthquakes at the Moho boundary. An upper mantle velocity of 7.95(¦ 0.15) km/sec was measured from travel times of selected shallow earthquakes along the strike of the island arc.

Jan 1, 1987

By A Gustafson, G Shekhar, P Boeg-Jensen

The amount of material extracted from each blasted ring in sublevel caving mines is vital when deciding the overall mine production target. The orientation of the production drifts is normally perpendicular to the strike of the orebody, and rings are blasted from the hanging wall side to the footwall side in a retreating manner. For an inclined orebody, a given ring will contain different amounts of material based on its relative position along the production drift. This layout creates a distinctive problem with respect to the extraction ratio optimisation along the axis of the production drift. This paper describes the current drawpoint control strategy practiced at LKAB and presents the variation of drawpoint performance parameters along the production drifts. It uses automatically generated data from a bucket weighing system that measures tonnage drawn per bucket, and it classifies the blasted rings into four zones based on their relative position along the production drift. It considers the loading procedure for blasted rings at Kiirunavaara mine and analyses the variations in drawpoint performance along the production drift. The paper finds that although the current draw control strategy is sensitive to ring position along the drift, it could be modified to optimise the final extraction ratio.CITATION:Shekhar, G, Gustafson, A, Boeg-Jensen, P and Schunnesson, H, 2016. Draw control optimisation along the production drift in sublevel caving mines, in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016), pp 241–250 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016

By T Leidich, M Van Zyl, H Lacy

Mining ‘as usual’, until the most recent decades has resulted in limited landform planning and a general lack of mine waste landform design. Material characterisation, mine planning and dedicated professionals undertaking these tasks were rarely available or in place at the majority of mines. This has led to landform instability, erosion, sediment and poor quality water emanating from mine landforms. In many cases rehabilitation and reclamation failed and these sites have ‘landform features’ that are difficult to relinquish or leave and have little or no apparent land use. In many cases mined landscapes around the world have resulted in a less functional and degraded environment, with deleterious impacts on surrounding ecosystems.This situation is now slowly being addressed, as global companies, academics and practitioners and their organisations have started to exploit the ideas from an integration of earth sciences and mining through the application of planning software dedicated to the design of landforms.This development has had its genesis primarily in the United States. We suggest that process has been driven, in recent decades, by the application of resources in response to the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA), (USA Congress 11 December 1980) and other mine reclamation legislation enacted by federal and states regulators in the USA. The combining impact has seen a huge transfer of capital back from the public purse and ‘potentially responsible parties’, into abandoned mines to affect control, remediation, and reclamation/rehabilitation of those mines.Given this investment in rehabilitation and reclamation, people engaging in the business of landform planning have had the opportunity to address landform reclamation of historic and active sites. The skills of engineers and scientists with improved technology, waste rock characterisation and modelling tools have been combined resulting in the evolution of landform design and in mine planning of active mines. This has delivered cost-effective, sustainable mine closure designs for over 30 years. Integration of mine design with an understanding of geomorphic principals and the natural landscape, coupled with waste and soil characterisation, yield a positive result. Recently work has been applied across large and small-scale projects by companies. As these processes develop, ideas and concepts are evolving that active mines, or mines in the early planning stages, could use to help reduce double handling, and in the long run reduce overall project and closure costs, more effectively attain the desired final land use, and enhance the industry’s reputation and licence to operate.CITATION:Leidich, T,?Lacy, H?and Van?Zyl,?M,?2014. Application of design concepts and engineering controls necessary to deliver well-designed and rehabilitated landforms, in Proceedings Life-of-Mine 2014 , pp 55–66 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 16, 2014

By M Tsai

Tube bundle gas monitoring systems have been used in the mining industry for over 50 years. The initial design was based on four individual gas analysers along with a series of solenoid valves, gas sample conditioning and flow control mechanisms to ensure the correct gas flow stream volume to the analyser. Simtars staff have identified flow control issues when providing operational support to coalmines on numerous occasions. The accuracy of the oxygen analysis is dependent on control of the gas flow to the analyser. Oxygen is one of the parameters used in calculating Graham’s ratio which is used for the detection of spontaneous combustion activity in coalmines. This paper will provide data which identifies the flow control issues by comparing mine site records for the two surface sample lines in the analyser room and the gas cage. Mine sites will be deidentified within the paper. The paper will discuss some of the changes that have been made in modern tube bundle systems and compare the change to the initial design specification developed by the UK National Coal Board, investigate possible operational impacts and provide a technical fix to solve the current flow issues being experienced at some mines.

Oct 12, 2022

Mr Chairperson, respected leaders of the mining industry, ladies and gentlemen;   Good morning, Kiora, Nihao.   I am very honoured to give a speech to the 2005 New Zealand minerals conference. I would like to take this opportunity to express my sincere thanks to the Ministry of Economic Development to invite me to be part of this important event.   Today, I am going to talk about two themes: a brief introduction of ChinaÆs economic development, including ChinaÆs energy strategy; the good bilateral relations between China and New Zealand, its potential for further development and its relevance to our cooperation in the field of minerals and energy.   It is a well-known story that over the past 27 years, great changes have taken place in China. In 1978 when ChinaÆs reform and opening up just started, its gdp was near to only 150 billion usd dollars. By the year of 2004 it reached to 1.6 trillion usd, an average of yearly growth rate 9.4 per cent.   ChinaÆs great achievements are widely appreciated both in China and abroad. ChinaÆs development has not only improved the living standard of its own people, but also produced a huge market and brought about great opportunities for the world. Since ChinaÆs entry into WTO in 2001, China has imported near to 1.8 trillion usd dollars of goods, averaging a yearly imports of 500 billion usd dollars, creating for other countries and regions more than ten million jobs.   Our prediction is that in the next five years, ChinaÆs imports will be well over three trillion usd dollars. China will continue to serve as one of the leading growth engines for the future world economic development. Now China is on its great strive to achieve the goals of improving living standard for all the Chinese people. We are trying to reach a quadruple gdp of 2000 by the year of 2020, namely to reach gdp four trillion usd, a gdp per capita 3000 usd dollars.

Jan 1, 2005

Australia as a leading producer of mineral sands has also occupied a leading position in many areas of research'in the processing and applications of these minerals. Research in upgrading ilmenite to produce synthetic rutile has resulted in the develop- ment of many processes, e.g,., Becher, Murso, Chlorine Technology, and ICI processes. Studies on the reducibility of ilmenites, aqueous leaching of reduced ilmenites, Fe-Ti-O system, leachability of natural and treated ilmenites in hydrochloric acid and selective chlorination of iron from ilmenites have been carried out in order to develop and improve the efficiency of the above processes. While research on the processing of zircon sand to produce high purity (99.99% ZrO2 zirconia powder and zirconium chemicals started only recently, research by CSIRO in the early 1970s led to the discovery of the phenomenon of transformation toughening in partially stabilized zirconia (PSZ) ceramics. Australia, with very significant resources of lanthanide-containing ores, pro- duces substantial quantities of monazite each year but research in processing and appli- cations of rare earths was neglected in recent years in this country. However, research to improve processes for the recovery of rare earths is now under way and studies on the production and testing of Nd-B-Fe magnets which are 1.5-2 times stronger than the strongest magnets (Sm-Co) currently available, have also commenced.' An overview of the research in the pro- cessing and applications of mineral sands during the last two decades in Australia and its implications for the industry are pre- sented in the paper.

Jan 1, 1986

By E R. Ramanaidou, C Tessarolo, M Verrall

Garnierite mineralogy in saprolitic ore of the Goro lateritic nickel deposit, New Caledonia , was investigated using X-ray diffraction (XRD), optical and scanning electron microscopy (SEM) and electron microprobe (EMP) analyses. These conspicuously, green-coloured phases occur either as submillimetre to centimetresized veins or as æbookletsÆ arranged in, macroscopic (subcentimetre sized), accordionlike structures supported in an undifferentiated matrix of mixed ÿ7+ and ÿ10+ phases. Within the veins, nickel for Mg solid solution increased from ten wt per cent NiO at the edge to 34 wt per cent NiO at the core, with vein edges comprising Ni-kerolite with <1.5 Ni per formula unit (pfu) grading to pimelite containing >1.5 Ni pfu at vein cores. The æbookletsÆ comprised nTpouite of formula, (Mg0.67Ni1.59Fe3+0.05)(Si2.17Al0.22)O5(OH)4 and averaged 30 per cent NiO. SEM element mapping highlighted the distribution and mineralogical association of Ni and Mg and emphasised the inverse relationship between Ni and Mg at the macroscopic (thin-section) scale. An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation.

Jan 1, 2008

By J Yamatomi, Y Tamanishi, S Miwa

The four-dimensional (4D) network relaxation method, originally developed by Akaike in 1999, uses Lagrange relaxation and is known for its ability to include the price change and possible better outputs, but the computation time is huge. However, the continuous advancement in computer technologies allows the use of higher-speed computers with more memory capacity. Therefore, in this paper the authors have tried to implement the method with adjustments and improvements in its algorithm to suit the current computing system. As a result, the computation time has been drastically reduced and more constraints can be included, which makes the scheduling a more realistic one. The case study of an open pit gold mine with 129 500 blocks can be solved considering the capacity constraints in 71 seconds. In previous case studies, the mined ore had to be processed or disposed of immediately. Now, stockpiling can be included as another option. Since the details of the algorithm are still being improved, the computation time is a little longer than the previous cases without the stockpiling option. However, it is found that scheduling with the stockpiling option is possible in a reasonable time. In conclusion, the 4D network relaxation method has become more useful with advances in computer technologies and provides better results.

Sep 26, 2011

By J A. M Luz, A T. Bernardes

HukkiÆs law is an empirical law, which does not take into account several events of energy loss during the fragmentation processes. Since experimental results are very difficult to obtain, for a large range of fragment sizes, the verification of the law is very difficult. The relation between fractures and fragmentation processes with fractal geometry was proposed some decades ago. Empirical laws known in this context show basic features of fractal geometry, mainly self-affinity and power law behaviour. Thus, in this work a model was developed to simulate the fragmentation process and to check the relation between energy consumption and fragment sizes. The model is represented on a regular lattice. Links can represent pathways for fracture processes. The events of fragmentation have energy given by a probability distribution function. In the model there is no mass loss. Propagation of fractures occurs as self-avoiding random walks on the regular lattice.

Sep 26, 2011

By R J. Romañach

The theory of sampling (TOS) is now followed in the development of near infrared (NIR) spectroscopic methods for the pharmaceutical industry. TOS has been the guiding light for a two-step approach for spectroscopic composite sampling available for the development of real-time analytical methods for particulate-based industrial processes. The two-step spectroscopic sample composite has been used in the development of process analytical technology (PAT), an important regulatory initiative to improve the quality of pharmaceutical products. The two-step sample composite approach overcomes the low sample volume analysed by PAT methods; one of the key limitations to PAT implementation in the industrial production of particulate-based materials.PAT methods need to be validated demonstrating their accuracy, precision, specificity and robustness. TOS provides a deeper understanding of these validation studies which involve discrete particulate material. The validation of PAT methods is now being performed considering both sampling and analytical errors, while practically all previous method validations only addressed the total analytical error (TAE) of these methods. This has been a crucial impediment for the field of chemometrics as well.PAT is a key element of continuous manufacturing (CM) processes, which are considered an emerging technology capable of increasing the flexibility, agility and robustness of pharmaceutical processes while reducing their costs. The outflow of the continuous process is a 1D lot, and variographic analysis has been shown to discern process variation from sampling and analytical errors in pharmaceutical CM processes. Thus, variographic analysis is a process improvement tool with significant potential for improving CM processes. The possibilities for improving pharmaceutical manufacturing are enormous.CITATION:Romañach, R J, 2017. Theory of Sampling – from missing link to key enabler for process analytical technology, in Proceedings Eighth World Conference on Sampling and Blending , pp 63–68 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2017

By P D. Munro

"This is a reprise of the paper ‘Back to the Future – Why Change Doesn’t Necessarily Mean Progress’ presented to the Tenth Mill Operators’ Conference in 2009. It was observed that the ‘boom and bust’ cycles of the industry, together with trends in tertiary education and the effects of fly-in fly-out (FIFO) operations raised serious questions about the sustainability of human capital in the mineral processing sector.In 2016 we find ourselves in a ‘bust’ after enjoying a decade of the longest commodity price ‘boom’ in a century. In the ‘boom’ did we:make any technological breakthroughs?put measures in place to improve our human capital, especially in the area of ‘professional formation’?The paper makes observations on the current performance of mineral processing engineers and the organisational milieu in which they operate. It questions whether mineral processing engineers are actually ‘adding value’ at some sites given their organisational and operational practices.Some technical trends are examined and what it might mean for mineral processing engineers.Given the above and demographic trends for mineral industry professionals, changes to the seemingly current laissez-faire model of professional development are proposed.Citation:Munro, P D, 2016. Back to the Future - Still on the Dark Side, in Proceedings 13th AusIMM Mill Operators’ Conference 2016, pp 341–348 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Oct 10, 2016

Anglo American Metallurgical Coal (AAMC) manages five open cut coal mines in Queensland and New South Wales, producing approximately 30 million tonnes per annum. The size and complexity of these mines require efforts by a large and diverse number of personnel to minimise adverse geotechnical events from occurring. To achieve this, the AAMC coal mines in Australia are developing a concept of managing the geotechnical risks associated with open cut coal mines. The overall system utilises a combination of internal training, a management system (operational management systems) and standards, numerical modelling, monitoring, inspections and audits. The development of the standards as well as training and mentoring of exploration personnel, geotechnical engineers, engineering geologists and mining engineers with an interest in the geotechnical aspects of mining, training of the production workforce, mentoring and training of the technical staff create the basis for achieving a pro-active rather than a reactive system. Audits are used to assure that personnel are maintaining the standards and to facilitate cross-mine leanings so that best practices are developed across all sites.

Nov 25, 2010

By T Baumgartl, M Edraki, L Huang, D R. Mulligan

"Phytostabilisation with tolerant plant species has been advocated as a cost-effective solution for sustainable cover of tailings from metal mines and bauxite refinery. The development of sustainable plant ecosystems on such wastes requires not only tolerant plant species compatible with local climatic conditions, but also the formation of stable and functional root zones through systematic processes to develop functional soil matrix and horizons (eg A-B-C). However, the process requirements for reconstructing functional root zones in tailings are poorly understood. Based on a review of current literature and industry experience in tailings revegetation, the present paper conceptualises three key phases in the process of root zone development in amended tailings: hydro-geochemical stabilisation resulting from the interactions among tailings characteristics, amendment measures and local climatic conditions the rehabilitation of soil biological capacity the establishment of ecological (carbon and nutrient) linkages between the rehabilitated root zones and the above ground plant communities.Key research is required on: the relationship between hydro-geochemical stability and mineralogy and geochemistry of tailings, in response to rehabilitation treatments under local climatic conditions the relationship between soil biological capacity and hydro-geochemical stability in the root zone the transition of soil microbial communities specific to exogenous organic matters into those required for mineralising litters of in situ plant communities.CITATION:Huang, L, Baumgartl, T, Edraki, M and Mulligan, D R, 2012. Sustainable phytostabilisation of mine tailings - A critical analysis of system requirements and approaches, in Proceedings Life-of-Mine 2012, pp 105-116 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Jul 10, 2012

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 O Jones

Longstanding occupational health challenges of the underground hard-rock mining sector require both an analysis of historical data to assess evidence of linkages between the source of the problem and subsequent illnesses, as well as investigating the means by which health risks to workers can be eliminated or minimised. This paper refers briefly to a recently established National Health and Medical Research Council (NHMRC) sponsored Epidemiological Study into the incidence of Lung Cancer, contracted by mineworkers in Western Australia (WA) due to the inhalation of diesel exhaust fumes from 1996 to 2012. Thereafter it reviews current knowledge of the nature of the challenges facing those responsible for the health and wellbeing of underground hard-rock miners in WA, commencing with the recent categorisation of diesel exhaust as ‘Carcinogenic to Humans, Group 1’, by the World Health Organisation’s (WHO) International Agency for Research on Cancer (IARC). An attempt is also made to explore how the challenge has changed with the adoption of more advanced engine technologies, including the increased generation of ultra-fine volatile organic and other nucleates, submicron carbonaceous agglomerates and toxic gases.The compounding effect of using the mine decline access entry as both the primary ventilation intake and haulage-way is also discussed, as is the need to develop a more appropriate metric for regulating diesel engine emissions. Finally the paper refers to ongoing in-mine research pursued by the National Institute for Occupational Safety and Health (NIOSH) at its Diesel Laboratory in an underground limestone mine near Morgantown in the USA.CITATION:Jones, O, 2015. Diesel exhaust and the underground miner in Western Australia, in Proceedings The Australian Mine Ventilation Conference, pp 167–172 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 31, 2015

By C Slaughter, J C. Tien

Commonly held ideas about effective training have long emphasised the importance of realism. Realistic training builds better experience among the trainees and a better perspective on the training material, making training more effective. While great strides have been made in this realm for mine safety and mine rescue training there are still areas that can be improved. One possible area is the expanded use of a mine fire simulation program where the migration of gases and smoke can be realistically displayed in an emergency, and outcomes varied as different conditions are being simulated. The use of mine fire simulation software potentially allows for the creation of more realistic scenarios in that smoke advance rates can be measured and recreated in evacuation scenarios, or that gas readings in mine rescue training can be dynamically and realistically changed to show the effect that time has on the fire scenario.CITATION:Slaughter, C and Tien, J C, 2015. The potential use of mine fire simulation software as an enhancement for mine safety and mine rescue training, in Proceedings The Australian Mine Ventilation Conference, pp 285–290 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 31, 2015

The history of the discovery and development of the Kambalda nickel orebody. is reviewed and the decision to process the Kambalda concentrates by the Sherritt-Gordon process at Kwinana is discussed. The Kwinana Nickel Refinery is described and the problems encountered in the first year of operation are Outlined.

Jan 1, 1971

By M Rafty, C Lane

Managing water is a key aspect of mining, whether a site is in water surplus or water deficit. Water in tailings storage facilities (TSFs) needs to be managed carefully to maximise the density of the solids, maximise the re-use of available water and to minimise the risk of water overtopping the spillway in the event of heavy rainfall. Developing a water balance models is a standard method for monitoring the major flows of water around a site. However, models created by specialist consultants are often overly complex and are not suited to being used by process plant personnel after they have been handed over to the mine operator. Models typically offer information on water management at the time that they are created, but then ‘sit on the shelf’ and offer no further insight or value for operating mines. Advisian has developed a customised water balance model for a mine in Sub-Saharan Africa, which can be adapted to other locations, to assist in managing water at the site and in particular to predict the current and future water level and volume in the TSF under various rainfall scenarios. The model was developed using Microsoft Excel and requires no specialist skills to operate. Site personnel enter in daily production, water transfer and rainfall data and then view the output dashboards to observe the current water level and volume, decant rates, licensed water abstraction and water supply versus demand. The output dashboards were developed in close consultation with the client to ensure that all of the relevant key performance indicators were included, from the perspectives of all the key stakeholders. This modelling approach focusses on the needs of the people who will actually use the model to actively manage TSFs with the need to involve the model developer as part of ongoing operations eliminated. The simplicity of this approach is now being embraced by other mine sites in Africa and Australia. CITATION:Rafty, M and Lane, C, 2018. Water balance management 101, in Proceedings Mine Waste and Tailings Stewardship Conference 2018, pp 485–490 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 23, 2018

This paper discusses the implementation and potential limitations of the method for estimating sampling and analytical errors of multiple source mine output blended into a shipping product, described by Everett and Ziegelaar (2010). The practice of quality measurement varies between iron ore miners. The common objective is to monitor effective resource utilisation and control of product quality to customers. A flow diagram is given presenting the various options used by iron ore mine operators and the merits of the different options are discussed.

Mar 1, 2010

Applications of chlorine metallurgy to the extraction of metals often result in the production of volatile metallic chlorides, most of which condense directly to a solid phase at 1 atm pressure. A stirred-bed condenser suitable for the recovery of these materials is described.The unit, developed from the concept of a fluid bed condenser, has the advantages of versatility of operation and ability to control fog and dust formation. Test work using aluminium chloride vapour (as an example of a volatile chloride) gave recoveries approaching 100 per cent. The yield was dependent upon halide content of the vapour, flowrate, and, to a lesser extent, upon coolant temperature. Analysis of the heat transfer dataindicated condensation side coefficients in the range 10 to 30 B.T.U./hr sq. ft. 0p.

Jan 1, 1971