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The Stawell Goldfield, the westernmost of the main Victorian fields, has produced over a million and a quarter ounces of gold from one and three-quarter million tons of ore. The lodes are quartz reefs and sulphide bodies occurring in sediments of lower Ordovician or upper Cambrian age. The lodes are confined to a relatively narrow suite of weak rocks lying between stronger ones above and below and there is a definite relationship between fold structure, pitch and strength of folding and ore.LOCATION HISTORY AND PAST PRODUCTIONThe town of Stawell, situated 150 miles north-westerly from Melbourne on the main railway and road to Adelaide, is the most westerly of the main gold areas of Victoria. Alluvial gold was found at Pleasant Creek (now Stawell West) in 1853 and the usual "rush" followed. Numerous alluvial leads, some surface, others buried under up to 100 ft. of Tertiary sediments were worked. The alluvial gold was soon exhausted, but in 1857 gold-bearing reefs were found on the slopes of a prominent ridge on the northern edgeof the present town. Early reef mining was by small working parties mining to shallow depths only and treating their ore at public crushing plants. Some of the early returns were very high grade. The next stage was the amalgamation of claims and the formation of companies, with their own treatment plants. This stage continued till the last mine closed in 1921. These companies had, by present standards, small holdings and far too many shafts were sunk, resulting in less efficient prospecting and operation.Since 1921 there have been one or two small scale attempts to revive mining but without success. Of recent years Gold...

Jan 1, 1960

By Nixon C. A

The exploration of Mount Isa Mines' new copper source will require the development of a five kilometre 4.7 x 5.5 metre blind decline commencing 1000m below the surface and extending to 1600m below the surface. With virgin rock temperatures approaching 60¦C, the ventilation strategy represents a complete departure from any previously used at this mine, in that refrigeration becomes essential. The use of direct water to air cooling techniques has become commonplace in mines throughout the world and their application is being adopted at Mount Isa Mines. A heat load simulation routine has been implemented to allow for the design of refrigeration requirements, as well as to aid in the selection of diesel or electric equipment. This enabled planners to determine the size of a surface based refrigeration plant. Future refrigeration demand for expansion into the ore production stage has also been investigated.

Jan 1, 1988

By Kato Y

As a direct result of the Mining Industries need to improve efficiency and production in Open Pit type operations, the size of haulage units have increased dramatically. This trend has continued such, that the majority of dump trucks operating in Open Pit operations are in the 170 ton class. Continued mining in existing locations has meant that the increase in vertical lift and resultant grades, and increases in hauling distances are making electric drive systems unsuitable. This is largely due to the electric drive systems heat limitations on major propulsion components. With these mining requirements in view and the present limitations on electric drive systems in mind, Komatsu have been developing the Komatsu HD1600M. A diesel powered mechanical drive dump truck capable of operating in deep pit operations. This presentation introduces: Komatsu HD1600M Dump Truck

Jan 1, 1982

By Heape JM

Production from the Cattle Grid orebody commenced in August, 1974. This followed a recent discovery arising from an extensive exploration programme involving stratigraphic drilling, geochemistry and geophysics. Located some 4 km west of the original copper occurrences at Pernatty Lagoon the discovery was found to contain 4.6 million tonnes of ore averaging 2.4% copper. The ore is a "sandstone copper" type localised near the disconformity between two Precambrian (Adelaidean) stratigraphic units, the Pandurra Formation and the Whyalla Sandstone. The mineralisation roughly follows the interface between these units and occurs in fractures, vugs and along bedding planes. The mineralogical character of the ore is somewhat complex consisting of chalcocite and bornite, with associated chalcopyrite, sphalerite, pyrite and other less common sulphides. 1. Senior Geologist, Pacminex Pty. Limited, Sydney, N.S.W. 2. Mine Geologist, for Mt. Gunson Mines, Pacminex Pty. Limited, Mt. Gunson, S.A.

Jan 1, 1975

Carbonate-hosted massive sulfide ores of the American cordillera compose a distinctive genetic class. Discordant fea-tures of occurrence together with measured high-temperatures of formation indicate their essential epigenetic character and close spatial association with centers of thermal activity during evolution of the cordillera. Their metallogenic character is complex from region to region: Cu-Zn-Pb-Ag, Pb-Zn-Ag, and Cu-Zn-Ag-Au represent extremes of composition and each may be identified with specific terranes of occurrence, notwithstand-ing an inferred common process of formation. Beyond the presence of a thermal center, other controls that may be identi-fied include apparent but obscure properties of primary perme-ability or chemistry of hosting strata, and secondary controls are imposed by stratigraphic differences in which permeability is strongly contrasted. Structures that act as channelways may be identified in some instances. Notwithstanding their intrinsic value, search for these ores is difficult and requires the solution of complex geochemical and three-dimensional geometric problems.

Jan 1, 1990

By A Vickerfält, J Huss, J Martinsson

The European Union has listed vanadium (V) as one of the critical raw materials for the transition to a future green society, as stated in the Critical Raw Material Act, written by Grohol and Veeh (2023). In the steelmaking industry based on V-containing iron ore, V is a possible by-product from the slag. A requirement for slags to be suitable for V extraction is a V content preferably above 8 wt per cent as V2O3 and a phosphorus (P) content below 0.1 wt per cent as P2O5. Hence, it is important to keep V in the slag phase while the P is moved to the metal phase during the steelmaking process.

Aug 21, 2024

By BTrubT M

In the roast-leach-electrolysis process for the production of zinc, iron contained in zinc concentrates is converted to zinc ferrite during roasting. At Canadian Electrolytic Zinc (CEZinc), the Outokumpu Conversion process is used to simultaneously leach zinc ferrite and precipitate the iron as jarosite. These simultaneous reactions, while providing good process stability, require a compromise between optimum conditions for maximum zinc extraction and efficient iron precipitation. An improved conversion process has been identified which can achieve >99 per cent zinc extraction and more efficient jarosite precipitation to residual iron concentrations of

Jan 1, 1993

By D Kubik, K The

The New Zealand (NZ) Transport Agency’s Waterview Connection will complete Auckland’s Western Ring Route, a 47 km north–south motorway alternative to Stage Highway 1. The project is being delivered by the Well-Connected Alliance comprising the New Zealand Transport Agency (NZTA), Fletcher Construction, McConnell Dowell Constructors, Obayashi Corporation, Parsons Brinckerhoff NZ, Beca Infrastructure and Tonkin & Taylor.The project involves construction of 5 km of new motorway, nearly half of it underground connecting State Highway 20 (SH20) to State Highway 16 (SH16). The underground portion of the project incorporates twin 13.2 m inside diameter (ID) tunnels 2.4 km long, each carrying three traffic lanes, one for north-bound traffic and one for south-bound traffic. The tunnels are being driven by a 14.46 m outside diameter (OD) 2400 t, tunnel boring machine (TBM) shield that was assembled and launched at the southern portal. It will be turned and re-launched at the northern portal for the return drive to the southern portal where it will be disassembled. This paper presents two major temporary works elements contributing to the successful launch of the TBM: the TBM assembly crane platform and the TBM shove frame and associated components.Tunnel boring machine shield assembly – crane platformThe TBM shield was delivered to site in subassemblies ranging in weight from 100 to 380 t. It was initially proposed to use a 750 t crawler crane sitting above the tunnel portal headwall to assemble and disassemble the TBM. However, this did not have sufficient capacity to allow the TBM shield to advance clear of the tunnel before disassembly commences. To reduce the crane’s working radius a temporary steel crane platform was developed that is supported on the side walls of the tunnel approach trench. This has enabled a smaller, less expensive, 600 t crawler crane to be used and will allow the TBM shield to clear the tunnel before disassembly.Tunnel boring machine launch – temporary worksTo launch the TBM a purpose built steel frame was required for the TBM thrust rams to react against. The shove frame had to be able to transfer the thrust loads from the TBM shield to the ground below and thrust wall behind. A range of potential thrust loads and jacking patterns were examined to develop the design load cases for the shove frame. The shove frame was used to launch the TBM at the southern portal and to re-launch it at the northern portal. Elements of the shove frame will also be used to support the portal faces during the TBM arrivals.CITATION:Kubik, D and The, K, 2014. Waterview Connection – temporary works for tunnel boring machine?launching, in Proceedings 15th Australasian Tunnelling Conference 2014, pp 281–288 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 17, 2014

By P Craig, A Crosky, P C. Hagan, E Elias, B Hebblewhite, S Saydam, D Vandermaat

"Premature failure of rock bolts has been recorded at twelve underground coalmines over the past 15 years in Australia. Over the last four years, UNSW Australia has been conducting an Australian Research Council (ARC) and Industry funded linkage research project into premature failure of rock bolts. The extent of the problem was investigated by underground surveys of mines with known prematurely failed bolts using visual mapping, non-destructive load and ultrasound testing. A major component of this project was to define the environmental factors responsible for corrosion of rock bolts. The environment to which a rock bolt is exposed will include groundwater chemistry, the mineralogy of the strata, atmosphere within the drill hole and even microbial activity. This paper focuses on the groundwater survey and analysis findings to date along with in-hole bolt corrosion coupons installed into field sites. Corrosivity classification systems exist for general corrosion but do not apply to the rock bolt stress corrosion cracking (SCC) problem found in Australian underground coal. The method of in situ investigations is leading towards the building of a corrosivity classification model to assist mines in prediction of premature rock bolt failure. An ‘in-hole bolt corrosion coupon’ development by the project may have multiple benefits of: helping quantify any corrosivity classification system providing an in situ ground support corrosion monitoring tool for testing possible corrosion protection solutions.CITATION:Craig, P, Saydam, S, Hagan, P C, Hebblewhite, B, Vandermaat, D, Crosky, A and Elias, E, 2014. An investigation of the corrosive impact of groundwater on rock bolts in underground coalmines, in Proceedings AusRock 2014: Third Australasian Ground Control in Mining Conference, pp 277–286 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Nov 5, 2014

By J Boshoff, D Reid

It has been recognised worldwide that the liquefaction risk of unconstrained tailings stacks or cyclone underflow embankments requires careful consideration. The stability of a tailings deposit where the perimeter embankments are made up of hydraulic fill is often governed by post-liquefaction stability.Cyclones are frequently used around the world to classify tailings into a coarse underflow for building a tailings impoundment wall and a finer fraction that is disposed of into the basin. The shear strength of the tailings that form the outer embankment of a tailings storage facility (TSF) and the location of the phreatic surface are the two most significant factors influencing the structural integrity of the facility. The coarse underflow is placed in such a way as to contain the overflow, which is finer, has low strength and is often poorly consolidated.A cyclone field trial was undertaken at a gold mine in Western Australia to assess the feasibility of using the cyclone deposition method to optimise and increase the capacity of an existing tailings cell. The aim of the cyclone trial was to collect information to demonstrate to the client and the regulators that cyclone deposition was a feasible option for raising TSF embankments. The cyclone trial provided an opportunity to assess the cyclone under field conditions and the quantity and quality of the underflow fraction produced on-site. A variety of methods were used to assess the flow liquefaction susceptibility of the tailings underflow sample produced during the cyclone field trial.The field trial, laboratory testing and analysis will be discussed in this paper.CITATION:Boshoff, J and Reid, D, 2015. The resistance of cyclone underflow material to flow liquefaction, in Proceedings Tailings and Mine Waste Management for the 21st Century , pp 151–156 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 27, 2015

By B P. Wrench, M J. Gowan, P J. Chapman

Embankment dams constructed mainly of sand or non-plastic fine soils are susceptible to liquefaction, particularly in high-rainfall, high-seismicity environments where there is sufficient water to saturate the materials and sufficient energy from an earthquake to cause liquefaction. This paper shows the process adopted to review the stability of an existing cross-valley, centreline-raised cyclone tailings sand embankment dam.The study showed that two-dimensional stability analyses did not sufficiently capture the potential for instability, overestimating the depth of the critical failure surface. Instead, three-dimensional modelling was required to provide a reasonable representation. Post-liquefaction stability analyses carried out using the three-dimensional model indicated an adequate factor of safety (FoS). The FoS under seismic conditions was still considered to be a concern based on pseudostatic analyses (but noting the limitations of the analysis method).Earthquake-induced settlements were estimated using an empirical approach based on case history records (Swaisgood, 2003). The post-earthquake event settlement was estimated to be in the order of 600 mm, which is considered to be acceptable for the embankment, taking account of the proposed long-term freeboard of more than 8 m under operating conditions and 2 m under the probable maximum flood condition.CITATION:Chapman, P J, Wrench, B P and Gowan, M J, 2015. Review of static and seismic stability of a cross-valley sand tailings embankment in a high-rainfall, high-seismicity setting, in Proceedings Tailings and Mine Waste Management for the 21st Century , pp 163–172 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 27, 2015

By A Sainoki, D Fukuda, K Shioya, C Zhang, M Sharifzadeh, T Yamaguchi, S Saydam, J Kodama, C A. Amagu, Y Fuji

In an open pit mining, ensuring stability of rock slope has been one of the major challenges. As the instability of rock slopes can results in slope failures; consequently, endanger the lives of workers, affect mining operations, and often lead to economic losses. Therefore, it is practical important to study the stability of rock slopes to ensure safe, smooth, and effective mining. The stability of rock slope of about 130 m height at Higashi-shikagoe limestone quarry, which has experienced slope failures four times since 1996, was assessed. The rock mass at the quarry is consists of mainly limestone, schalstein and slate rocks intersected by clay seams of about 70 m thick at footwall of the rock slope. Previously, the effects of limestone excavation at the foot of the rock slope and shear failure due to rainfall infiltration have been investigated. Although clay is widely known to plays a vital role in the stability of slopes in engineering projects including mines, but its impacts on slope deformation at the study quarry are not adequately examined. Therefore, the present study addressed the impact of presence of clay on slope deformation at Higashi-shikagoe limestone quarry by employing both field displacement measurements and numerical simulation. Firstly, surface displacements measured by automated polar system (APS) for over eight years were analysed to understand the overall characteristics of the slope deformation. The measured results show that the displacement gradually decreases with time. The maximum displacement of about 100 mm was observed at middle of the rock slope. Secondly, the effect of deterioration and plastic behaviour of the thick clay layer were simulated using two-dimensional finite element method (2D FEM). The simulated results reveal that the clay exhibited deterioration by water contact and plastic behaviour arising from mining activities at the footwall of the clay zone. Based on the characteristics of the measured and simulated results, it was found that the displacement induced by the effect of deterioration of clay is more noticeable at the north side of the quarry whereas displacement induced by excavation is quite significant at the south side of the quarry if clay behaves as an elasto-plastic material.

Nov 29, 2022

By P A. Grossman, J H. Rubinstein, M Brazil

The installation of truck turntables at above-ground crushers has the potential to yield gains in efficiency and productivity by eliminating the need for the trucks to turn around and reverse up to the crusher to dump their loads. The benefits include savings in time, fuel consumption and tyre wear. In addition, having a smaller area near the crushers dedicated to manoeuvring the trucks can be a significant benefit at some sites. Safety is also enhanced using turntables.This paper describes a project with the Australian Turntable Company to develop software that generates near-optimal layouts for the paths taken by the trucks in the vicinity of the crushers when turntables are present or absent. The geometry of the paths is constrained by the turning radius of the trucks and by the boundary of the manoeuvring area. The software quantifies the benefit of installing turntables by generating a design for paths with turntables and comparing it with the layout in current or planned use by the mining company. Through the use of this software tool, a mining company can readily assess the benefits of using turntables at their site.CITATION:Brazil, M, Grossman, P A, Rubinstein, J H and Thomas, D A, 2014. Demonstrating efficiency gains from installing truck turntables at crushers, in Proceedings Orebody Modelling and Strategic Mine Planning Symposium 2014, pp 259–266 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 24, 2014

By Bain J. H

Since zinc was first deposited at Risdon in February, 1917, provision of the most economical cathode assembly has been a subject of extensive research, the major problems being corrosion and efficient use of power.From the corrosion viewpoint, a perfect cathode is one in which the life of the headbar and the deposition sheet are the same. However, corrosion usually concentrates in a narrow zone across the face- of the sheet, resulting in breakages which, before the advent of argon arc welding, meant a loss of a 'complete assembly.Attempts to extend sheet life included use of thicker sheets, multitudinous protective coatings applied with varying degrees of success, re-rolling, and for a time, aluminium consumption was reduced when broken sheets found re-use as protecting strips. This latter economy became impracticable when electrode spacing was reduced for greater efficiency in power utilization.As an integral part of the electrode, the headbar was modified accordingly. Copper headbars, although more corrosion resistant, were replaced by aluminium due to a possibility of dissolved, copper promoting deterioration.Thicker electrodes and regulated spacing reduced internal shorting, whilst provision of knife-edge type supports on both contact and insulator ends of headbars aided in electrode centralising and continuous electrical conduction.After much experimeIitation, an assembly has been evolved which, with the aid of argon arc welding and tbe use of minimum additional aluminium, permits comparable headbar and sheet lives, combined with good electrical conduction throughout the life of the cathode.INTRODUCTION Over 300 tons of zinc are produced daily at Risdon from a purified zinc sulphate solution by electrolysis, the zinc being deposited upon all-aluminium (except for copper contact) cathodes. It is stripped in 72-hour cycles from the cathodes, melted and cast into the customary rectangular slabs.

Jan 1, 1958

Many aspects of best practice resource evaluation do not create value, but poor practice can certainly destroy value. Generally companies prefer to present how their good practice adds value and for this reason few publications exist on examples of how poor practice can destroy value. However in big and small companies there are many previous and current examples of poor practice destroying value. The incremental expenditure required to move from poor practice towards best practice can be looked upon as insurance against destroying shareholder value. Examples of how poor practice in geology has destroyed value are presented as well as the improvement model used by BHP Billiton to add value and insure against destroying value.

Jan 1, 2002

The acid plant consists of the following units: 1. Glover tower. 6. Mills-Packard type chambers. 3. Reaction towers. 6. Gay-Lussac towers.The sulphur dioxide bearing gases, used in the manufacture of the acid, are obtained from the roasting of zinc concentrate. Six Herreshoff type furnaces are available, each with an effective hearth area of 520 sq. ft.The concentrate contains approximately 30% sulphur, of which about 72 is ultimately recovered as acid. The oxides of nitrogen are added to the gases in the requisite proportions partly from nitrous vitriol and from nitric acid in the Glover tower, and partly from nitrous vitriol in some of the chambers and connecting flues.The acid leaving the Glover tower is cooled by the ordinary water-cooling coils, while the cooling of the chamber gases is effected by circulating water over the outer surface of the chambers, and by spraying nitrous vitriol and weak acid into them.Flow of gases throughout the plant is regulated and controlled by means of regulus metal fans, fitted with variable speed gears.

Jan 1, 1934

In the past decade several significant intrusion-related gold deposits have been discovered in terranes historically exploited for tin-tungsten mineralization (eg Tintina Gold Province, Yukon and Alaska, Tasman Fold Belt, Australia and the Altaid orogenic collage in central Eurasia). This paper presents new data on the geological and geochemical characteristics of these deposits that links them to magmatic-hydrothermal processes and highlights their implications for exploration. New data from several intrusion-related gold provinces suggest that these deposits are found in areas that contain granodiorite to granite, but with a locally significant mafic component, have Rb/Sr ratios ranging between 0.1 and 1.0, and are moderately reduced (Fe2O3/FeO ~ 0.1 to 0.6) ilmenite series, metaluminous, I-types. The intrusions are distinct from porphyry copper intrusions and tin granites, but are more akin to tungsten granites. Hydrothermal fluid types vary with depth of emplacement in intrusion-related gold deposits and new proton induced X-ray emission (PIXE) data from syn-ore fluid inclusions in shallow and deep deposits provide fascinating insight into the variation in metal content between the different settings consistent with observed deposit metal associations. Exploration for intrusion-related gold deposits in tintungsten terranes should focus on regions that contain both mafic and felsic intrusion that are moderately reduced, metaluminous, I-type granites rather than terranes with dominantly highly fractionated, strongly reduced, peraluminous S-types. Intrusion-related gold systems occur in variety of deposit styles (in part controlled by host rock, proximity to granite, and depth of emplacement) and exploration geologists need to be aware of the variety of target types in and around the intrusive environment, and be able to recognise whether they are exploring a shallow or deep intrusion-related gold setting.

Jan 1, 2005

The structural pattern of Victoria shows the presence of EW, NW, NE as well as the more readily recognised NNW factors commonly associated with the goldfields. ENE and WNW trends are also present. This structural lattice affects all rocks of the State. Landsat imagery shows that the EW, NW and NE structural elements are closely related spatially to the distribution of Palaeozoic igneous intrusives, Cainozoic volcanic vents as well as all historically important gold mines. It is suggested that the EW, NW and NE structural grid visible on landsat imagery is a reflection of the structure of a mid-crustal layer situated between 3.5 and 17 kms below the surface. The points of intersection of the structural elements of the mid-crustal layer offer most favourable loci for the escape of energy in the form of heat. The correlation between the distribution of igneous plutons, volcanic vents and centres of mineralisation, all reliant on high levels of energy for their formation, indicates the stability of the structures of the mid-crustal layer since early Palaeozoic times. The deep level crustal structures are believed to be, related to the release of stresses placed on the crust since early Palaeozoic times by the rotation of the Earth. A geological model that accommodates the presence of a mid-crustal layer as well as the complexities of the recognised orogenic cycles of southeast Australia is suggested. All 1 000 kg Au reef and deep lead mines fall within 1.5 and 2.5 km respectively of strong linears associated intimately with plutons and volcanic vents. Future exploration of the State is more likely to meet with success if it too is confined to the evaluation of these and similar linears. The mode of mineralisation of any one centre will depend upon the temperature, pressure and geochemical gradients operating on the migrating mineralising fluids as well as the structures in the host rocks. These factors are likely to have varied considerably from one centre of mineralisation to the next and consistency of mineral isation form and depth should not be expected along the length of any single Linear.

Jan 1, 1986

By L Klemettinen, A Jokilaakso, D Attah-Kyei, P Taskinen, M Tiljander, D Sukhomlinov, D Lindberg

In this study, the use of carbon neutral biochars as reducing agents in the pyrometallurgical treatment of nickel slag was investigated at 1400°C in order to recover valuable elements such as copper and nickel from the slag. A large amount of slag is generated during the nickel matte smelting. Nickel slag contains valuable elements such as copper, nickel and cobalt, which can be recovered. Disposal of this slag results in loss of resources and may cause pollution of the environment. It is important to retrieve these metals for environmental and economic reasons. In this study, the slag was reacted with non-fossil reducing agents (biochar) which were produced from hydrolysis lignin and black pellet biomass pyrolyzed at 600 and 1200°C and with metallurgical coke for comparison. The reduction experiments were done at 1400°C for 15, 30 and 60 mins under inert gas atmosphere. The samples were quickly quenched and analysed with Electron Probe X-ray Microanalysis (EPMA). The results showed that the use of biochar resulted in faster reaction kinetics in the reduction process compared to coke. The fast reaction kinetics is attributed to the relatively high content of volatiles in this biochar, leading to gas formation and thus mixing of the sample material. Moreover, thermodynamic modelling was also performed using FactSage™ to simulate equilibria with different amounts of biochar. The metal to slag distribution coefficient calculated from the results of thermodynamic modelling were consistent with experimental results. In addition, thermodynamic calculations confirmed that nickel is reduced rapidly and it deports to the metal alloy phase. As the reduction progresses or extra reductant is available for reactions, more iron is deported to the metal phase. The calculations also revealed that Zn vaporises into the gas phase.

Jun 19, 2024

By Gupta R. C

Syria has about 500 million ton deposit of minerals having 34 per cent iron content with alumina and silica as major impurities. Efforts were made to see the feasibility of concentration by four different methods involving washing, high intensity magnetic separation, reduction roasting and magnetic separation and acid leaching technique. It was observed that the reduction roasting with magnetic separation yields a concentrate with high iron (62.3 per cent) content without requiring water which is a scarce raw material in the region. The paper concludes that the detailed study may be made following this route to optimise the process Parameters.

Jan 1, 1999