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P.IISTRACTThe Pacific Rim is advantaged by the uniqueness and diversity of its geological features. Why then is geology given so little regard in the education systems of the countries of this region? Not that these countries differ greatly from those in other parts of the world. Papers presented during the Precollege Geoscience Education session at the 28th International Geological Congress (28th IGC) held in Washington, July, 1989, indicated strongly that the problem is universal. There is a marked decline in interest in the Earth sciences and many nations are looking towards methods that might change this trend. Problems affecting geological education include the lack of purpose and direction, its obsolete curricula and the difficulty in attracting gifted students.The world-wide plight of geology comes at the very time when it should be fundamental to a public understanding of the global effect of human population pressure. There is a universal awareness of "the environment" but very little awareness of the science that has supplied most of the data. Geology, as the science of the Earth, is of paramount importance to an understanding of our life on this planet, particularly in its role as the source of our every need.

Jan 1, 1990

By Smith J. W, Hart G. N

Compositional and isotopic analyses of coal seam gases in the Southern Coalfields have shown that these gases frequently contain abnormally high concentrations of magmatically derived carbon dioxide. The size of this carbon dioxide reservoir and the extent of permeation of the sediments by carbon dioxide are not known.Therefore caution in evaluating the natural gas potential of the region is advised.

Jan 1, 1981

Gold deposits in Eastern China have characteristic of belted distribution. The concentrating belts of gold mineralization are about parallel to the island are belt in Western Pacific Ocean. Gold deposits are mainly concentrated in the aged metamorphic rock series on the upwarping zones and upwarping fault zones, and obviously controlled by the deep fractures and their deriva-tive secondary faults. Gold mineralization had genetic relation to the Mesozoic (especially Yanshan period) magmatic activity. The distribution and genesis of gold deposits can be explained by the assumption of wavy structure. The formation of wavy structure is related to the process of Pacific plate and India plate.

Jan 1, 1990

By J Isles, S King, A Valenza, R Lawolo, J Evert

PT Nusa Halmahera Minerals (PT NHM) is an Indonesian joint venture company owned by a subsidiary of Newcrest Mining Limited (75 per cent) and PT Aneka Tambang (Persero) (25 per cent). PT NHM operates two underground gold mines, Kencana and Toguraci at the Gosowong mine site in North Halmahera District, North Maluku Province, Indonesia.The Toguraci underground mine development commenced in 2011 with ore production commencing in 2012. Water temperatures ranging from 50°C to 80°C were encountered in the Toguraci open pit associated with the structures containing the gold bearing veins and are believed to be fed from a relic volcanic system one to two kilometres below the mine. Underground development and production has continued to intersect these structures with the result that an integrated programme of geological, hydrogeological modelling and operational project work has been required to dewater the mine ahead of the descending stoping fronts.This paper will detail these programmes.CITATION:Lawolo, R, Isles, J, Evert, J, Valenza, A and King, S, 2017. Hot water management at PT Nusa Halmahera Minerals’ Toguraci Mine, in Proceedings 13th AusIMM Underground Operators’ Conference 2017, pp 191–198 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Oct 16, 2017

The Prominent Hill copper-gold deposit is located approximately 150 km north west of Olympic Dam, on the southern margin of the Mount Woods Inlier in South Australia. Its discovery in November 2001 resulted from the application of a geological model developed from geological, geophysical and petrophysical data pertaining to the Olympic Dam deposit. The discovery has dispelled the notion the Olympic Dam may be unique, and that another deposit like it is unlikely to be found. The Prominent Hill mineralisation is hosted by haematite-matrix hydrothermal breccias, which have suffered extensive iron-sericite-silica alteration and overprinting. Copper, gold, barium, fluorine, uranium, cerium and lanthanum are all intrinsically associated with the hydrothermal iron. Breccias intrude an east-west striking, fault-controlled sedimentary succession, which is flanked to both the south and north by volcanic complexes. Many similarities between Prominent Hill and Olympic Dam are documented including geological setting, mineralogy, breccia styles, and alteration. Differences relate largely to the nature of the immediate host rocks. The similarities and difference provide key data for improving exploration models for this style of iron oxide copper-gold deposit, both within the Gawler Craton as well as globally.

Jan 1, 2004

By Blake W

Based on preliminary computer model simulations and stability analyses, both longi- tudinal and transverse, large dimension, cut- and-fill rooms were designed for the parallel dipping ore layers at Kamoto mine. Full scale testing of the designed rooms showed that the rooms are stable and that the rock behavior is predictable. Ordinary waste rock was selected as the filling material because the fill was found to carry little load.

Jan 1, 1973

Carbothermal Reduction and Nitridation of Ilmenite Concentrates and Chlorination of the Reduced Samples

Sep 13, 2010

By L M. van Niekerk

The mining of iron ore is a high volume low margin business because the value of this commodity is significantly lower than that of base metals. The main metallurgical challenges in most of the iron ore projects proposed for treatment nowadays have been in finding the optimum flowsheet for the treatment of magnetite ores, mixed magnetite-hematite ores and even ores that have banded ironstone formations (BIF). The associated plant designs incorporate very high capacity milling systems to grind the ore down prior to magnetic separation and in being highly capital intensive requires substantial investment in mega processing plants with associated infrastructure to mill down the run-of-mine ore to the desired treatment size for upgrading.To minimise the cost of infrastructure, better beneficiation techniques and technologies are being sought to assist in reducing upfront ROM feed to allow for reduction in overall treatment plant footprint necessary in extracting the desired downstream product. This paper discusses such beneficiation techniques and advancement in technologies for the upgrading of coarse and fine iron ore utilising dense media separation (DMS), jigging, wet magnetic separation, dry magnetic separation, flotation and x-ray processing.Another group of iron ore projects involve the mining of hematite ore below the water table. Often the mined ore is wet and sticky. This combination requires high capacity processing of feed material utilising large scrubbers or attritioning units to effectively remove the slimes component present in the feedstock. The fines removed, usually below 1 mm, are then discarded in large tailings storage facilities. Approaches to recovering the saleable material contained within these fines will also be investigated in this paper. This not only implies possible reduction in slimes discard footprint, but also holds potential benefit in augmenting overall yield and recovery of hematite product.CITATION:van Niekerk, L M, 2013. Fine and coarse iron ore beneficiation - An evaluation into global technologies and techniques, in Proceedings MetPlant 2013 , pp 584-598 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 15, 2013

By J-M Rendu

Substantial progress has been made over the last ten years in the development of uniform national and international standards covering the definition, estimation and public reporting of mineral resources and mineral reserves. Agreement between the major participating countries has been reached, which includes the requirement that a Competent Person prepare and approve publication of mineral resources and reserves. Most national regulatory organisations have accepted the new standards and have included them in the rules that must be followed by mining companies operating under their jurisdiction. These developments are the result of a concerted effort on the part of professional societies, national regulatory agencies, international organisations, and many dedicated individuals. The historical development of these standards is summarised in this paper. Accepted definitions of mineral resources and mineral reserves are discussed, as well as the definition and role of the Competent Person. Additional effort is needed before the international standards are fully understood, accepted and followed by mining companies, regulatory agencies, the investment community and the general public. Steps being taken toward development of an International Code are outlined.

Jan 1, 2002

By Ehlers HK

Mount Isa Mines Limited has 25 rod and ball mills of various sizes installed in two Concentrators at Mount Isa. A continuing investigation into installation, design and materials of liners for these mills has been in progress since the early sixties. Both manual and mechanical methods of liner installation are used and described. Materials for the various applications have been evaluated, mainly by field trials. Design of liners has also been evaluated by field trials and the history of trials in No.4 Concentrator is given. The purpose of the investigation has been to reduce the cost of mill lining and the life of many linings has been greatly increased as a result of this work.

Jan 1, 1978

By D J Rawlings

The Palaeo- to Mesoproterozoic McArthur Basin contains a thick (-10 km) intracratonic platform cover sequence of unmetamorphosed and relatively undeformed sedimentary and volcanic rocks (Pietsch et al, 1991). It covers an area exceeding 180 000 km2 of the North Australian Craton (Figure 1), overlying segments of the older deformed basement and transitional igneous units. Volcanism in the basin (including transitional domain) followed a four-phase pattern. These phases are geologically distinct and widely distributed, and are also recognised beyond the McArthur Basin in many similar-aged tectonic provinces in northern Australia. The four phases are described briefly below. Regional and structural nomenclature used refers to Figure 1. A stratigraphic correlation diagram is presented in Figure 2.

Jan 1, 1994

By E Jak, G Khartcyzov, M Shevchenko

The increasing complexity of ore resources and recycled materials in the feed of pyrometallurgical processes present a technical challenge to the metallurgical engineers working on maximising the recovery of the valuable elements and minimising the environmental impact of the processes. To address this challenge, the availability of computational tools that can predict the mass and energy balance in complex systems is required. Then the accurate description of phase equilibria in the complex multicomponent systems describing the chemistry of the pyrometallurgical processes becomes critical for the correct implementation of the indicated tools and facing the outlined industrial challenges. In the present study the distribution of selected elements (Pb, Zn, Fe, As, Sn, Sb, Bi and Ni) between oxide liquid and metal in the ‘CuO0.5’-CaO-AlO1.5 system in equilibrium with Cu metal at 1400°C (liquidus of CaAl2O4) was experimentally studied using the equilibration and quenching technique followed by the electron probe X-ray microanalysis of the resulted samples. The study covered a wide range of effective p(O2) over the system from 10-11 to 10-3.5 (corresponding to formation of immiscible CuO0.5-rich slag). To avoid loss of volatile elements (Pb, Zn, As, Sn, Sb and Bi), a correlation between ‘CuO0.5’ in oxide liquid and p(O2) in open system was obtained first, followed by studying the volatile elements distribution in closed conditions (Al2O3 crucible sealed in SiO2 ampoule), where ‘CuO0.5’ concentration was used as a marker to evaluate the effective p(O2) over the system. The experimental results were then used for the optimisation of the thermodynamic model parameters of the system as part of the integrated experimental and self-consisting thermodynamic modelling research program of phase equilibria in the Cu-Pb-Zn-Fe-Ca-Si-Al-Mg-O-S-(As, Sn, Sb, Bi, Ag, Au, Ni, Cr, Co and Na) gas/oxide liquid/matte/speiss/metal/solids system.

Jun 19, 2024

The invitation to speak today was in the form of a single sentence instruction: How does your company run and how do you communicate from top to bottom? It looks like I'll have to let you into our little secret. The team at Croesus know what works for us but we've never talked about it with others - least of all presented it at a conference such as this. In fact we tend to avoid the jargon normally associated with Best Practice or TQM, however in our own way, each of our staff are 100 per cent loyal to our company's aim to maintain and strengthen our commercial success. Just how we achieve this at Croesus is the subject of this presentation today, but first a little history. My dear old grandfather arrived in Kalgoorlie, as a mining engineer 100 years ago. Do you think he would have chuckled if someone suggested to him that a hundred years later we would just be starting to understand Kalgoorlie's geological mysteries? Well, here we are 100 years later and Croesus Mining is fortunate to be part of a generation now realising the true potential of Kalgoorlie's Goldfields. This provides us with a very fertile field in which to sow the seeds we can obtain from the World's Best Practice in Mining and Processing. With each new mineral deposit being discovered, old theories are being exploded. Each new deposit has a personality of its own, leading to some belated pioneering theories of where to drill next, and how to reduce internal costs so that we can win the war against constantly increasing external costs. What we have now and what the old timers didn't have is a huge database of geological input spanning several gold booms and a couple of nickel booms. My only interest in history is to pick up the points that may help us for our future. This is what we are doing in our company which is something of a David, in the David to Goliath range of mining companies in Australia. As a humbling thought; of the 115 164 tonnes of gold that the world's mines have produced throughout history, four tonnes have been produced by Croesus Mining. That's equivalent to 0.003 per cent of the total world's gold production. In the past financial year we achieved a dividend yield of five per cent. To put this into perspective, that's over twice the dividend yield of BHP, Australia's largest company. As we are somewhat less known than BHP, let me spend a few moments giving some particulars of our company's background.

Jan 1, 1995

By Collins M. J, Ozberk E

A major advantage of the Sherritt Zinc Pressure Leach Process is the conversion of sulphide sulphur in zinc concentrate to elemental sulphur during pressure leaching. Elemental sulphur can be recovered as a marketable byproduct by flotation of the leach residue, and melting and filtration of the sulphur flotation concentrate. The behaviour and deportment of sulphur during pressure leaching, flotation, and melting and filtration are discussed in this paper using data obtained from the treatment of a wide variety of zinc concentrates in the laboratory miniplant at the Sherritt Research Centre. The quality of the elemental sulphur byproduct and a process for purifying the sulphur are also Presented.

Jan 1, 1993

By G J. Harbort, V Lawson, L Reemeyer

The Jameson Cell is a high intensity flotation device, which utilises induced air from the atmosphere. It was developed jointly by Mount Isa Mines and Professor Graeme Jameson of the University of Newcastle in the 1980s. It is proven to generate fine bubbles, in the order of 300 to 500 ¦m, in a high intensity, high shear and compact zone contained in the downcomer. This aerated mixture exits the downcomer into the pulp zone, which is the quiescent mineral and gangue separation zone. A number of Australian base metal flotation circuits feature a reverse flotation stage at the head of the circuit. Testwork and plant operating data has shown that the use of a Jameson Cell in the prefloat cleaner application has further improved prefloat gangue recovery and selectivity. Operation of a Jameson Cell in a carbonaceous/pyrite prefloat cleaner duty at the Mt Isa copper concentrator increased copper recovery and reduced pyrite in the copper concentrate. Testwork at Zinifex Century Zinc Mine showed a decrease in zinc losses by the utilisation of Jameson Cell prefloat cleaner. Appraisal of a Jameson Cell in a scalping role within the Mt Isa Copper Concentrator indicated significant benefits could be achieved.

Jan 1, 2005

By N LaBranche

The resurgence of Silicosis and Coal Worker’s Pneumoconiosis (CWP) in coalmines has placed the spotlight back on the management of worker exposure to particulate matter across all mining sectors (Coal Workers Pneumoconiosis Select Committee, 2017). There already exists a substantial body of knowledge on particulate matter and its impacts upon human health (National Academies of Sciences, Engineering and Medicine, 2018). The contribution of silica to respiratory disease is well known. However, it is also clear that there are major gaps in our understanding. In part, those gaps relate to the contribution to adverse health effects of mineralogical constituents in the dust (LaBranche et al, 2021a). It is also becoming evident that the size and shape of the particulate matter can affect its potential impact on human health. The University of Queensland has developed a methodology for characterising respirable and inhalable dust samples using scanning electron microscopy. Multiple samples from numerous mining operations have already been analysed using the UQ methodology. The process has been successful in showing the variety of mineralogical components and particle size distributions present in various areas of the mines.

May 5, 2022

By W A. van der Westhuizen, Beukes G. J, Vermaak J. J

Large parts of the arid northern Cape Province South Africa are blanketed by Quaternary cal- crete under which potential base-metal ore- deposits may occur. In an attempt to examine the nature of the distribution of such ore-re- lated elements in a calcrete environment, calcrete and soil samples from the copper-nic- kel prospect at Jacomynspan and the copper- zinc deposit at Copperton were examined. Both deposits form part of the Namaqua mobile belt. CALCRETE GENESIS In Southern Africa calcrete is restricted mainly to the western two-thirds of the sub-continent, south of the latitude 17¦ S. Various models have been put forward to explain calcrete genesis and Goudie (1973) and Netterberg (1969a) give detailed discussions on this topic. The most popular model for calcrete genesis is one of pedogenic origin. McPherson (1979), Watts (1980), Wright (1982), Arakel (1982), Netterberg (1969a), Goudie (1973) and Multer and Hoffmeister (1968), amongst others, support the hypothesis of calcrete formation by carbonate precipitation from downward percolating calcium carbonate rich soil waters. Calcium carbonate is usually initially precipitated as nodules or grains which can develop to form more compact layers.

Jan 1, 1988

By D J Williams

Coal washery wastes comprise tailings, finer than 0.5 to 0.1 inn depending on the sophistication of the washery, and coarse reject, typically finer than 50 mm. Subaerial disposal of coal tailings slurry at about 30 per cent solids by mass results in the formation of a delta with an average slope of about 1 in 100, representing one extreme. The ravelling of coarse reject on loose-dumping, results in an angle of repose slope with an angle of about 37" (1 in 1.3), representing the other extreme. The pumped co-disposal of coal tailings and coarse reject results in the formation of an upper delta with an average slope of about to one in ten, between the two extremes. The depositional behaviour of these three waste streams is discussed and compared in this paper. The important depositional and material parameters, and a theoretical description of the processes involved, are also presented. Comparisons are made between the depositional behaviour of the various coal washery waste streams, and natural depositional systems, such as rivers, alluvial fans, and scree slopes.

Jan 1, 1998

Palaeostress analyses of the northeast-dipping Koki Fault Zone demonstrates in the hanging wall an east-west compressive stress and sinistral reverse-slip. Data from the footwall region are more uncertain and may relate to rotation of the stress field during fault motion. The fault-plane solution of the 1979 Port Moresby earthquake (Modified Mercalli Intensity 5-7 at epicentre 70 km east of Port Moresby) shows east-west compression and a stress field identi

Jan 1, 1997

By Beeby C. j, Fernando W. J, Ming M. Q I, Guang Li Xi

Removal of moisture in steam-fluidized, mainly steam-heated, fluidized beds makes possible significant energy savings over conventional forms of large-scale drying. The systens are described and their applications to brown coal and alumina hydrate are reviewed. In application to brown coal the use of the system to permit meeting diurnal variation in power station output, and the use of triple-effect drying to minimise coal usage and to avoid the necessity of recovering in the turbines the energy in the steam from the last dryer are discussed. To facilitate the rapid adoption of the systems proposed, studies are being made of heat-transfer to dried coal, of moisture equilibrium in pressurized and vacuum systems, of tapered beds as a means of reducing carrier steam and permitting wider size variation, and of the use of carrier solids for drying lump materials.

Jan 1, 1989