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By Haslam C. O, Los V. L, Abramson G. J

The technology applied by lonex Pty Ltd provides an important breakthrough in geochemical exploration, enabling the discovery of concealed mineral deposits to great depths below surface. Most mineral discoveries have been made in areas of outcrop or relatively shallow cover; deposits at greater depth have been beyond the range of conventional geophysical and geochemical methods. Quite apart from the need to explore to greater depths in regions of major current or past production, most continents have vast areas where prospective host rocks are concealed by more recent material. There are numerous case studies where Ionex methods have located deeply-buried metal deposits, up to 500 m below surface, beneath thick younger sedimentary, volcanic, or transported cover. Research leading to the development of this technology was initiated by Dr I S Goldberg at the Rudgeofizika Institute in St Petersburg (CIS), and the methods have been employed there - and in other countries - for many years. Ionex technology became available in Australia in 1993. It comprises: ò geochemical and geoelectrochemical sampling and ultra-high-sensitivity analysis for mobile and weakly-bonded elements (I S Goldberg); ò the delineation and interpretation of regional zones of enrichment and depletion of the prime elements within geoelectrochemical systems (GES) (I S Goldberg); ò the investigation and interpretation of the three-dimensional geochemical zoning within geochemical anomalies (G J Abramson); and ò multi-variate computer modelling of the geochemical fields and systems (V L Los). lonex technology has been adapted to the environmental conditions in Australia with the participation of C 0 Haslam.

Jan 1, 1997

By Nixon TR

The Australian Coal Industry Research Laboratories Ltd. (A.C.I.R.L.) MINVENT computer program can be used to simulate existing and projected colliery ventilation requirements. New collieries can be planned using a database of ventilation parameters which were ascertain- ed by A.C.I.R.L. surveys at selected collieries in N.S.W. and Queensland. Several techniques are used in both the formulation of the database and in the evaluat- ion of a ventilation system, prior to analysis by the MINVENT program. The analysis of a ventilation system requires the measurement of air quantities, pressures and hence airway resistances. All resistances are calculated at standard air density of 1.205 kg/m3. Air densities are derived from barometric pressure and wet and dry bulb temperature readings. Airway frictional and shock losses, leakage through stoppings and overcasts, flow of air through regulators, face resistance and resistance of anomalous ventilation features are related to the typical Australian measured data presented.

Jan 1, 1983

By D Craw

The Macraes gold deposit is located in a low angle NE dipping (~15¦) shear zone, the Hyde Macraes Shear Zone (HMSZ) cutting greenschist facies metasediments of the Otago Schist. The shear zone is host to large volumes of mineralised schist and relatively sparse quartz veins. Early in the development of this through going shear the schist experienced an episode of hydro fracturing and fluid redistribution. As a result, presently exposed schists within the Intrashear sequence are pervaded by localised swarms of quartz filled pure extension and extensional shear fractures hosting goldscheelite mineralization. The swarms comprise networks or æstockworksÆ of veins that strike NE, are subvertical and form subperpendicular to the shear zone fabric. Vein frequency across strike is typically ~1 m-1, with most veins five to ten centimetres thick and vertically continuous for up to ~20 m. Many of the veins show delicately banded internal textures that are parallel to the vein margins. These bands/lamina indicate incremental growth and are defined by a variation in grain size or alternatively by thin slivers of wallrock schist, though typically uncommon. The majority of veins are overprinted by a weak plastic deformation, although primary structures are largely preserved. This deformation has produced subgrain structures, migration of grain boundaries with sutured margins and undulose extinction of grains. These microstructural observations possibly indicate that temperatures were around 300¦C during stockwork vein formation. In general, the mode of brittle failure that developed the stockwork veins can be directly related to lithological variation. The geometry of stockwork veins indicate that local vertical shortening and extension occurred in the Intrashear sequence of the HMSZ synkinematically with thrusting. Localised extension was mainly parallel to the structural trend; that is, it took place perpendicular to the direction of inferred thrusting. The development of lateral ramps most likely gave rise to extension in parts of the shear zone during continuous shortening to form swarms of stockwork veins.

Jan 1, 2004

By Stokes WPC

The capital requirements to develop a new mining venture are becoming very large; amounts of the order of US$1,000 million are not now unusual among estimates to bring new mining complexes into production. At the same time prevailing political and economic conditions are making it increasingly difficult to determine whether or not a project is likely to be viable. These factors emphasise the need to carry out thorough evaluation studies of all mineral prospects before making major investment. Additionally with the rapidly changing economic climate existing at the present time, it is becoming more and more necessary to carry out reappraisals of existing mines. An important function of both initial evaluations and reappraisals is to provide the operators of the mine with effective mining plans to ensure that the operation will meet its required economic targets. P, p M. tl p b, c v, s c 1 n 1 f r d c e c e u w Modern computers are well equipped to store and manipulate large amounts of data with speed and reliability. Their use in the mining field r is increasing and this trend serves to free f technical staff from much of the time consuming m and error prone hand calculations which were o formerly required in determining reserves and w carrying out all forms of mine planning. r Nevertheless, computers are not a universal

Jan 1, 1980

By C Zhang, R Liang, I Canbulat, S Saydam, B Li

The integration of digital twins in mining represents a significant advancement towards enhancing operational efficiency and decision-making. Central to this development is the role of visualisation, a crucial element in mining digitalisation. This paper aims to develop a data-driven visualisation solution for the construction of mining digital twins, highlighting how this innovation revolutionises the representation of physical mining environments. It spotlights the shortcomings of conventional visualisation methods, particularly their inability to accurately depict complex underground environments and their predominantly historical orientation. To address these challenges, this paper proposes a novel, data-driven approach. This approach extensively utilises CAD files, encompassing data from geological surveys to intricate mine plans, thereby significantly elevating the precision of digital twins. It supports real-time updates and enables flexible interaction with a variety of data types. Moreover, it introduces a comprehensive data diagram alongside the adaptation of a 3D tile index. This strategy ensures the efficient rendering of extensive mining environments, allowing for a more dynamic and interactive digital twin model. In conclusion, the implementation of data-driven visualisation in the construction of mining digital twins marks a pivotal advancement in the industry’s digital transformation. It promises a more detailed, accurate, and dynamic depiction of mining operations.

Sep 1, 2024

By Walshe JL, Solomon M

The Emperor vein system lies on the eastern margin of the Tavua volcanic structure. This is of Miocene age and occurs in basalts(the Mba Volcanics) probably underlain at about 2 km by calcite-rich sediments (the Vatukoro Formation). The lodes are generally flatmakes, or steep fault fillings, or complex shatter zones, and consist of quartz and altered wall rock. In areas of open cavities it is possible to establish a paragenesis which involves five quartz stages and two ore mineral stages. The first ore stage contains calaverite, krennerite, sylvanite and native tellurium, the second petzite, hessite and native gold. The quartz stages are thought to have formed slowly (102 years) from boiling solutions of low salinity at temperatures varying with time from about 250¦C to 190¦C. The system was sealed, the temperature gradient near vertical and the mass flux small. The ore mineral stages probably formed relatively rapidly (101years) from boiling solutions at 250¦ to 200¦C when the system was mainly open. Gold deposition was probably largely a result of fall in aH2S due to boiling, the calculated solution concentration falling from a maximum of about 8 ppb at 250¦C to about 8.10-3ppb at 200¦C. Boiling is also probably responsible for an increase in a02 (by loss of H2) and fall in aTe2 (by loss of H2Te). The fluids are thought to have had a large component of meteoric water and to have been heated by plutons in the core of the volcanic structure. Stable isotope data indicate that they derived their carbon from the underlying Vatukoro Formation and their sulphur from sediments. Circulation may have been confined to the outside of the volcanic structure because of the relatively low permeability of the flows, pyroclastics and dykes within it.

Jan 1, 1987

Structural Controls Interpretation of regional aeromagnetics, radiometrics and satellite image data has identified three structural domains (fig 2): The Fairyland Domain: a general N - S structural trend. The Cracow Domain: a general NW - SE structural trend. The Bald Mountain Domain: a general N- S structural trend. Known mineralisation is confined to the Cracow Domain in which there occurs two major NW - SE trending fault zones. The Cracow Fault Zone (CFZ) and the Immy Creek Fault Zone (ICFZ). Enhanced detail of the CFZ (fig 3) shows three main structural trends within it: NW-SE structures which include the mineralised White Hope South fault zone and the Golden Mile fault zone. NE-SW structures which have an influence on mineralisation in the Orange Creek, Fernyside and Golden Plateau areas. N-S structures comprising several major structural zones.

Jan 1, 1990

At the Highway gold deposit, 37 kilometres south of Charters Towers, gold mineralisation occurs in several stratiform layers and is enriched near the surface by lateritic weathering. The host rocks of the mineralisation are ferruginous and baritic, intensely sericitised, kaolinised and silicified rhyolitic tuffs and pyroclastics of the Cambrian-Ordovician Mount Windsor Volcanics. The geology of the deposit is illustrated in Figures 1 and 2.Forty-six reverse circulation percussion drill holes were completed by North-Queensland Resources N.L. for a total of 2,093 metres of drilling to further outline and test the open pit resource. The drilling indicated a resource of 171,000 tonnes averaging 4.4 grams per tonne gold and 5.0 grams per tonne silver.A shallow initial pit, approximately 30 metres deep, has been designed to mine the high grade upper portion of the western stratiform layer and part of the eastern layer. This initial pit is designed to mine 45,400 tonnes of western mineralisation at an average grade of 7.84 grams per tonne gold and 22,200 tonnes of eastern mineralisation at an average grade of 1.42 grams per tonne gold. Waste is estimated at 110,900 tonnes.

Jan 1, 1986

By X Xia2, X Wang, G Liang, T Song, F Ma

Inertia cone crushers have found applications mostly in steel slag crushing operations in China. Compared with conventional eccentric cone crushers, the crusher has an obvious advantage in reducing product size. In addition, they are mostly used in two-stage open circuit crushing flow sheet, which simplifies the crushing process. However, inertia cone crushers are not widely used in the mineral processing industry due to their low crushing capacity. In this paper, the throughput performance of the inertia cone crusher was investigated in a laboratory-scale inertia cone crusher and relationships between operational parameters were identified. Iron ore was crushed using orthogonal experimental method under different machine parameters and operational conditions. The crusher throughput and product size distributions were determined. The effects of parameters such as eccentric speed, discharge gap, eccentric mass and eccentric distance on product mass flow and product size were investigated. The results of this study can help reduce the feed size of the mill in order to reduce total energy consumption of comminution.

Aug 24, 2022

By Kubo H, Ninomiya R, Ojiro T, Sato T

New high-strength Zn alloys for moulds are demanded from the automobile and electric industries in Japan, because the s rength of Zn moulds is still not high enough for the mass production. There are two approaches to improve the strength of Zn alloys. One is to increase the Al content. ZA alloys (ZA-8, ZA-12, ZA-27) were developed through this approach. The other is to increase the Cu content. But it is known that an increase in Cu generally depresses the castability of Zn alloys, so that the alloys with increased Cu have been rarely studied until now. In this study a reconciliation between the strengthening and the castability of Zn alloys by enriching both with Al and Cu has been attempted. Accordingly we have studied on the Zn alloys containing 4 to 25 mass per cent Al and to 24 mass per cent Cu have been studied. Their fluidity, which primarily corresponds to the castability of the alloy, were measured first and 19 alloys were selected based upon their fluidities and casting temperatures. Mainly the mechanical properties of all 19 alloys were tested and some were found to be excellent in both strength and castability. Z1009 (Zn-IOAI-9Cu-0.02Mg alloy) cast in a sand mould has the tensile strength of 360 MPa while ZAS (Zn-4AI-3Cu-0.04Mg alloy), which is the most popular alloy for moulds, is 215 MPa. Z2520 (Zn-25AI-20Cu-0.02Mg alloy) cast in a sand mould has a Vickers hardness of 178, compared to 107 for ZAS and 104 for ZA-27 (Zn-27AI-2Cu-0.02Mg). Furthermore the castability of Z1009 is as good as that of ZAS. The underside shrinkage occuring in casting ZA-27 is restrained in Z2520.

Jan 1, 1993

By Grady B. V O, Cavell K. J, Ault A. R, Newman O. M G, Malcolm J. McPhersqn

Cyclic voltammetry (CV) has been evaluated as a technique for monitoring the quality of an industrial zinc sulphate electrolyte. The basis of the method involves measuring a change in the polarisation of the zinc nucleation reaction at an aluminium surface and relating this to the impurity content and/or the overall quality of the electrolyte. Specifically, the technique aims to be able to indicate and quantify detrimental synergism between impurity elements, something which traditional analytical techniques are incapable of providing. The technique has found some success with regard to monitoring glue additions in a range of metal electrolytes. It has been found that investigations by a number of workers over the past 15 years have produced variable and often misleading results due to the inadvertent use of commercial purity aluminium working electrodes. It has been shown that impurity elements in the working electrode can give rise to a range of responses that are not obtained when pure aluminium is used and that the response is variable due to the lack of surface homogeneity of commercial purity aluminium electrodes. Furthermore, it was demonstrated that previous detection limits reported in the literature were based on the presence of additional peaks in the cathodic scan and not polarisation effects. The results of this study have shown that when a pure aluminium working electrode was used, the method was incapable of detecting any change in polarisation for an electrolyte containing three common impurities (Co, Ni and Ge), at concentrations that would significantly reduce optimum electrolytic performance. A range of methods was tried to sensitise the technique, including raising the temperature and acidity, and adding antimony in order to induce some synergism. In all cases the polarisation response was unchanged. Consequently, apart from the commercialised application for monitoring additions of antimony and levelling agents such as glue, CV has very limited application as an electrolyte screening technique.

Jan 1, 1993

Exploration for uranium in Australia commenced only during the 1940s, but in this short period has been very successful as one third of the world's low cost uranium reserves have been discovered in Australia. Total uranium exploration expenditure in Australia up to the end of 1983 was $A(1983) 554 million; this discovered 20 potentially economic deposits and official reserves of 560 000 tonnes of uranium oxide at an average cost of $1 per kg of U 0 . An exponential 8 eserves indicates distribution of uranium r that there could be 54 undiscovered uranium deposits in Australia, each with reserves of 20 000 tonnes U308 or more, in addition to smaller deposits. Using a constant uranium price of $A(1983) 79 per kg, no deposit is economic at a grade below 0.12 per cent U 08 or with reserves of less than 3 000 tonnes. Selecting deposits with reserves of 5 000 tonnes U 0g or more as prime exploration targets, only 39 per cent of discoveries will yield a real internal rate of return (IRR) of 10 per cent or more. After committing a minimum exploration budget of $10 million to this search, an explorer has one chance between 7 and 12 of discovering a deposit that will repay the exploration investment.

Jan 1, 1984

By J Skousen, C E. Zipper

"Prior to the 1950s in the USA, surface coalmines were generally left without any reclamation. As government regulations advanced, mine operators were required to backfill the area and plant grasses or trees. After the federal Surface Mining Control and Reclamation Act (SMCRA) was passed in 1977 in the USA, mine operators were required to conduct pre-mining analyses of the site and to designate a land use that could be achieved after the mining. Common post-mining land uses in the USA are: agricultural uses such as prime farmland reclamation with crops, hayland and pasture, and biofuel crops forestry wildlife habitat building site development.Provisions and regulations for each post-mining land use were developed and practices to achieve successful and sustainable land uses were established. Post-mining conditions should provide ecosystem services and produce lands capable of supporting societal needs in the future.CITATION:Skousen, J and Zipper, C?E,?2014. Post-mining land use options in the Appalachian coal mining region of the USA, in Proceedings Life-of-Mine 2014, pp 153–164 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Jul 16, 2014

To follow the development of the central crushing plant it is necessary briefly to outline the history of the Lake View and Star Limited. This Company, when first constituted, took over the properties of the Lake View Consols, Hannan's Star, and Chaffers Gold Mines.The Company then treated the ore won from these leases at two dry crushing, all-roasting plants, situated adjacent to each other on the site of the present Chaffers Treatment Plant that handles all the ore won by the Lake View and Star Ltd.SUbsequent to the initial union of the three companies mentioned, the Ivanhoe Gold Corporation and the Golden Horse Shoe Ltd. were absorbed. Still later, and after the original crushing plant was erected, the Associated Gold Mines of Australia were purchased.A very extensive development policy was adopted by the Company's management in the late 1920's, and as the underground programme progressed, it became eVident that a large treatment plant would be required. Wet milling of the ore, followed by flotation, was considered desirable, and the necessity of a central crushing plant capable of producing a feed that could be handled by the wet ball mills attached to it was obvious.At this time, each of the properties absorbed had its own crushing station, situated adjacent to the respective...

Jan 1, 1948

A four monthly period was analysed for each retreating longwall face which indicated that output increased from 1140 tonnes/day for Longwall 1, to 1620 tonnes/day for Longwall 2 and to 2090 tonnes/day for Longwall 3. An output of 2500 tonnes/day should be achieved from the new Longwall 4, largely due to the improved tailgate corner design and despite a continuing lump coal problem. The evolutionary trend is a feature of longwall mining; the evolution occurring both with mining and mechanical design at the colliery itself and with the longwall equipment offered by manufacturers. The trend is towards simplicity, increased strength and capacity, simplified maintenance and increase relia- bility.

Jan 1, 1976

The Kidston breccia pipe is situated approximately 280 km west northwest of Townsville, north Queensland. It is currently Australia's largest gold producer with production varying between 8,000 and 16,000 tonnes of ore per day. Current reserves are estimated at 36.2 million tonnes averaging 1.74 C/t Au and 2.21 g/t Ag. Alluvial gold in the gullies surrounding the deposit was first discovered in the 1880's and between 1907 and 1948 small scale open cut and underground mining was undertaken. Advances in extractive metallurgy and an increase in the gold price were major factors influencing the recent exploration and development of large scale mining of the deposit by Placer Pacific and Kidston Gold Mines. The breccia pipe is trapezoid in shape with surface dimensions of 1100 m by 900 m. Clasts show only limited evidence of mixing during brecciation, with the pre-breccia stratigraphy still discernible on the basis of clast types. This lack of mixing together with the intimate association with intrusive activity, suggests that the brecia formed by collapse, probably associated with the escape of a large volume of irothermal fluid from a crystallising hatholith. Mineralisation and alteration are also sratially and temporally associated with rhyolite emplacement and brecciation. Pre-breccia mineralisation consists of laminated stockwork quartz veins associated with muscovite, quartz and orthoclase-epidote alteration. Stockwork veins contain either anomalous molybdenite or gold. Uneconomic early stage post-breccia mineralisation and alteration consists of cavity infill quartz-epidote and calcite associated with potassic and propylitic alteration respectively. Economic late stage post-breccia cavity infill and sheeted veining consists of quartz-carbonate-sulphide infill associated with phyllic alteration. The grade of gold mineralisation generally decreases downwards in the system with an increase in the amount of pyrrhotite relative to pyrite. Pre-breccia stockwork quartz veins mineralisation is genetically related to the

Jan 1, 1987

By Finlayson E, Hilyard D

1:100 000 geological mapping of Bougainville Island has resulted in refinement of stratigraphic subdivisions and relationships. We subdivide the sequence into basement Atamo Volcanics (Late Eocene-Early Oligocene), consisting of spilitised pillow basalts, which are overlain unconformably by Late Oligocene-Early Miocene Keriaka Limestone. The latter is unconformably overlain by fine-medium grained volcaniclastics and minor lavas of the Middle-Late Miocene Toniva Formation which coarsens upward and passes gradationally and conformably into the coarsely volcanolithic latest Miocene-Pliocene Arawa Conglomerate. The Kupei Complex, host to the Panguna.porphyry Cu-Au deposit, consists of medium - K20 microdiorites, granodiorites, and andesites intruding Arawa Conglomerate and Toniva Formation. K/Ar isotopic dates on the Kupei Complex range from 4.8-1.3 Ma, and hence overlap the age of the Arawa Conglomerate. We believe that the Arawa Conglomerate consists of mass flow deposits on a volcani- clastic apron surrounding a volcanic edifice above the intruding Kupei Complex.

Jan 1, 1990

The Manto Verde copper mine (Atacama Region, Chile) is due to go into production in 1996. It will produce 40 000 tonne/year of copper cathode by heap leaching/SX-EW. Mineralogical studies were undertaken in conjunction with the metallurgical testwork program to characterise the ore and its response to leaching by dilute sulphuric acid. The leachable copper mineralogy is dominated by the oxide copper minerals: brochantite and malachite with minor chrysocolla and atacamite. The gangue minerals include abundant orthoclase, specularite, quartz and chlorite with minor muscovite and trace smectite clay, calcite and limonite. The study showed that complete or partial decomposition of calcite, chlorite, smectite and wad consumed acid and generated solution impurities (Ca2+, Fe2+, Mg2+, A13+, K+, Si4+ and Mn4+2+ ). Although these were manageable at Manto Verde, their uncontrolled build-up could have affected the operation in several ways: the degradation of heap penneability and fonnation of crud in the SX plant from the precipitation of gypsum, goethite, colloidal silica and jarosite; and the entrainment of contaminated pregnant leach solution in the SX organic resulting in the transfer of impurities to the electrolyte and subsequent effects on cathode quality and electrowinning efficiency. In conclusion, process mineralogy played an important role in understanding and managing potential mineral-related problems in the heap leaching and SX-EW recovery of Manto Verde ore.

Jan 1, 1994

The Ore Reserve System implemented at Mount Isa for Mount Isa Mines Limited is a comprehensive' computer system designed to process assay, geological, structural and survey data for Isa and Hilton Mines. This paper outlines the achievements of this system to date and by example, discusses the various reports and plotted output available. __ The impact of the ore reserve system particularly within the-Geology and Mine Plan ning Departments is reviewed in terms of new approaches to ore reserve calculations, evaluating the economics of various mining methods and reviewing preliminary stope designs. The compilation of metal distributions for both copper and lead orebodies at varying cut offs and reducing the involvement of skilled personnel in preparing non-standard plots of borehole paths are discussed. Options available through the system and their applications are outlined together with the planned future development of the system.

Jan 1, 1974

By Coppock BW

Sintering of lead and zinc concentrates is practised by Sulphide Corporation Pty. Limited to provide both desuiphurised lump sinter feed, for simultaneous reduction to zinc and lead in the Imperial Smelting Process blast furnace, and sulphur dioxide gas for sulphuric acid manufacture. From November, 1969 a 20 percent increase in production rate has been obtained through improvements in operating technique. A gradual increase in bed permeability was achieved by modifications to the feed mix conditioning equipment and by improving moisture control. However advantage could not be taken of the higher permeability to increase sulphur elimination because the hardness of the lump sinter decreased. Higher throughput, better quality sinter and more stable sintering conditions were however made possible by simultaneously: 1. reducing segregation and compaction in the sinter bed, by narrowing the discharge opening of the main layer feed hopper, 2. reducing the sizing of sinter returns to give a closer size spectrum of particles in the feed mix, and 3. increasing the sulphide sulphur content of the feed mix to give higher bed Temperatures.

Jan 1, 1972