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The Australian Mining Industry Council (A.M.I.C.) was established in 1967 as a body to co-ordinate the interests of the mining industry on a nation-wide basis. Its member- ship now embraces the great majority of mining groups in Australia. One of A.M.I.C.'s major continuing functions since its formation has been to work with Governments towards the enactment of more effective and efficient mining legislation. Yet, over the period, the,overall position, if anything has deteriorated. The main reason for this was that because of the rapid succession of what appeared to be quite separate problems during the period there was never sufficient time for Govern- ments to take stock of a situation before it would be changed by a new set of circumstances. By early 1973, the Council was certain that most of the various questions raised were really part of the one overall land use problem and its work in this area thus took a new emphasis from that time. In discussing the Council's involvement with Australian mining legislation over the last six years, the paper helps to clarify the present situation. It then explains a land management system which the Council believes could pro- vide the basis for the type of enlighened

Jan 1, 1974

By Bishop I, Toon S

To determine whether 130 felt earth tremors around Edwinstowe, Nottinghamshire U.M, which also experienced severe surface fissuring, were caused by coal extraction, a surface seismometer array was established around Thoresby Colliery. Over the next year, 785 microseismic events were detected. The spatio- temporal seismicity patterns are clearly associated with the commencement, continuing extraction and closure of faces. Of particular note are events which locate at the surface and appear to be related to the active fissuring. Events occur within days of commencement of production and cease when production finishes, with good correlation between face advance and hypocentral position. Naturally occurring microseismic events have also been detected up to 1 km ahead of active longwall faces in the Midlands using triaxial geophone packages grouted into the seam together with a surface seismometer in the top of the borehole. The quality of these data were very high and guided waves can clearly be seen with the dispersive characteristics associated with seam waves. In one experiment more than 2000 events were detected in only two days of monitoring even in a relatively noisy surface environment. This paper demonstrates how very accurate locations (5 10 metres) can be generated using three-component digital data from only one borehole. The surface seismometer and the borehole P-wave onset can give extra precision for the height of the event relative to the seam. The event distributions give a dynamic, three-dimensional image of the developing patterns of fracturing above, below and ahead of the longwall face with important implications for roof control, subsidence prediction and gas Migration.

Jan 1, 1992

In high stress mining environments, production drill rigs are often employed for rapid drilling of boreholes for systematic cable bolting. One outcome of this drilling method is the need for larger boreholes than would normally be drilled using customised bolting machines, such as the Tamrock Cabolter. Past laboratory studies indicate that, under ideal grouting conditions, borehole diameter has little effect on the pull-out strength of cable bolts with high bulb densities. However, the sensitivity of pull-out strength to large boreholes and less ideal variations of grout strength have not been investigated. To explore these sensitivities, industry standard single embedment tests were conducted on large boreholes simulated using steel pipes. Four borehole diameters were tested, namely: 42 mm, 52 mm, 81 mm and 106 mm. In each case the grout water to cement ratio was varied from 0.35 to 0.45 and two cable bolt bulb spacings were considered, namely: one and three bulbs per metre. The results indicate that, across the range of parameters tested, variations in peak axial load at failure corresponding to changes in hole diameter were statistically insignificant.

Nov 25, 2010

By M E. Watson

Minimising dilution and ore loss is an important part of ensuring profitability of a gold mining operation. White Foil open pit gold deposit is a low-grade deposit and therefore managing ore quality is a high priority. Ground movement through blasting can displace ore and waste boundaries up to 10 m from their in situ location and therefore requires stringent ore movement monitoring and adjustment. There are currently only two options for monitoring blast movement – utilising visual targets (commonly lengths of polypipe) but this has widely been replaced by electronic blast movement monitors (or BMM). Regardless of the technology used, the basic principle is to compare the pre- and post-blast locations of the targets to determine the movement of the rock mass during blasting, which is then used to determine the final location of ore and waste boundaries.The Blast Movement Technologies (BMT) BMM system has been used at White Foil since June 2014. The system has been effective and reliable during that time; however, the annual cost of using the BMM system is greater than other monitoring alternatives. As such, the open pit geology team conducted a study comparing the BMM system against the conventional polypipe technique. The objective was to quantify the profit and loss that would occur based on the ore block transformations from both methods. Eight blasts were selected where polypipes were installed in additional holes adjacent to the BMM monitoring holes. The resulting movement vectors from the respective methods were used to create post-blast ore blocks by transforming the in situ ore blocks. While polypipe is a cheaper alternative, the BMM system tracks ore and waste boundaries more effectively resulting in better quality control, enhanced ability to minimise dilution and ore loss thus maximising profit. For these eight blasts, it is calculated that the BMM system resulted in A$664 978 extra profit through a reduction of ore loss. The total cost of a yearly BMM package was recovered in the first two blasts of this study. The primary reason for the difference is that polypipe had a poor recovery rate of 32 per cent compared with 92 per cent for BMM at White Foil. Therefore, the data used to transform the ore blocks was less representative, resulting in inaccurate post-blast ore block boundaries when using polypipe.CITATION:Watson, M E, 2017. Blast movement monitors or polypipe? A study into cost-effective blast movement monitoring at White Foil gold mine, Western Australia, in Proceedings Tenth International Mining Geology Conference 2017, pp 433–440 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 20, 2017

By R W. Shaw

The MTM Process targets treating lower grade and/or problem concentrates that are not attractive to smelters. The process has been developed at laboratory scale for copper and is based on a related development for zinc that has been extensively developed both in the laboratory and through pilot testing. The basis of the process is novel ammonia-ammonium chloride leach chemistry adapted to give high copper extraction whilst being selective over iron, arsenic and many other elements. The preferred flow sheet depends on location, especially infrastructure and utilities. These impact upon the leach and crystallisation stages more than copper reduction.

Aug 24, 2022

By J Butler, N Patel, S Narendranathan, S Rastogi

The Yallourn Mine (YM) commenced mining of brown coal in the 1920s under operation by the State Electricity Commission of Victoria (SECV), prior to it becoming privatised in 1996. The present owners of the YM, Energy Australia Yallourn (EAY), acquired the site in 2000 and intend to continue operations until scheduled closure in 2028. Brown coal extracted from the YM is fed into the Yallourn Power Station which supplies approximately 22 per cent of Victoria’s electricity. Water within the YM is collected and stored in the Township Field Fire Service Pond. Water levels within the Fire Service Pond (FSP) may fluctuate considerably depending on the requirement for storage at the site. With due consideration to the stability performance of mine batters adjoining the FSP, the authors performed slope stability assessments to evaluate the risk and consequence of batter instability during the potential pond filling as it approaches the ‘critical pool’. The critical pond is defined as the level at which the driving forces (destabilising forces) are at their greatest and the resisting forces (lake forces, friction) are at their lowest. This assessment was undertaken using the Mine Geotechnical Risk Index (MGRI) approach.

Aug 2, 2023

By M Svartsjaern, D Saiang and K Mäkitaavola

The Kiirunavaara mine is a large-scale (28 Mt/a) iron ore mine located in northern Sweden. The mine is owned and operated by Luossavaara-Kiirunavaara Aktiebolag (LKAB) using sublevel caving (SLC). The SLC area underlies an open pit decommissioned in the 1950s, the current main SLC haulage level is situated at an depth of 1100 m. The main orebody dips 60 degrees to the east with a distinct boundary defining the hanging wall to the east and footwall to the west. Since the 1980s damage has been observed both in the footwall rock mass as well as on the footwall crest of the open pit. Recent investigations indicate that the underground footwall damage is primarily controlled by large-scale slope failure mechanisms. Structurally controlled near-vertical planar shear failures in the upper footwall appear to be driven or facilitated by a step-path like curved shear failure situated in a zone starting ca 250 m, and intersecting the SLC about 100 m above the active mining level. To confirm this failure evolution a pilot underground measuring system has been designed and installed to monitor the expected rock mass displacements indicated by numerical models based on the above mechanisms. The systems consists of 50 m time domain reflectometry (TDR) coaxial cables installed in the footwall both across and away from an estimated damage extent boundary to monitor shear movements along natural joint surfaces. The TDR installation is combined with long extensometers to facilitate differentiation between diffuse shear and rock mass normal expansion. Additionally, a low-tech system of tape extensometer lines are installed in drifts and stopes running perpendicular to the ore strike to monitor horizontal displacements in the infrastructure as the footwall ‘slope’ loses confinement during mining advance when the mined out areas are replaced by caved rock from the hanging wall.CITATION:Svartsjaern, M, Saiang, D and Mäkitaavola, K, 2016. Underground footwall monitoring at the sublevel caving mine – Kiirunavaara, Sweden, in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016), pp 773–780 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016

THE area of the State of New South Wales is not great, nevertheless it has very large and important Mineral Resources. This is the more noticeable when the values of the annual mineral production from the individual States of the Commonwealth arecompared with the value of the New South Wales production. The principal minerals mined now are not gold, copper, and tin, as they were in the early years following the gold rush of 1851, the centre of gravity of commercial mineral activity having moved to coal and "oil-shale," water, limestone (with cement), silver-lead-zinc cadmium, sulphur, slate and other building and ornamental stone, road materials, and clays.From small areas totalling only 650 sq. miles, coal to the extent of 311,000,000 tons, valued at £151,000,000, has been won.The estimate of actual and probable reserves by the Mines Department within an area of less than 1000 sq. miles is about 14,000,000,000 tons, while the potential reserves within the remaining 15,500 sq. miles of concealed coal fields must be enormous. Even taking into account only the actual and pI:obable reserves in the 1000 sq. miles known, and assuming a depletion at the rate of 350,000,000 tons a year, or somewhat greater than that of the British Isles at present, and assuming an average value of £1 a ton, with money at 5% compound interest, then the present value of this coal (40 years of depletion) would be £5,575,000,000 approximately: truly an enormous present value for a business of 40 years, dealing only with 1000 sq. miles of country. The location of the main coal basin in New South Wales is one of great strategic importance. It lies almig and near a seaboard, with excellent facilities for anchorage; the coal is of very high quality, and is readily accessible; the climate is admirable. Were this same coal at Port Darwin, its commercial importance would not be be pronounced.

Jan 1, 1926

By E Kabwe, M Karakus

Deep hard rock underground mines tend to experience high stress as such drives exhibit dynamic responses attributed to a rock burst variant (strainburst). This dynamic behaviour is difficult to predict, and every effort is made to devise the appropriate dynamic support system for its associated failure restraint. This paper outlines the back analysis and the support scheme design for an underground decline that exhibited damage from a dynamic strainburst occurrence. It employs a decline section that experienced a dynamically loaded strainburst that initiated rock fragment ejections. The procedure involves a preliminary structural analysis, a seismic intensity measure, and a rock mass simulation to determine the static stress concentration and ground support system response. The numerical simulation is conducted in FLAC3D which employs the advanced strain-softening IMASS constitutive model governed by two Hoek–Brown (HB) bounding yield surfaces. To account for the post-peak brittleness response associated with strainburst the plastic strain multiplier () is adjusted to 0.0 < < 1.0. The back-analysis shows that the occurrence was initiated by a low-intensity seismic wave that superimposed an extra stress component to the initial static stress which triggered rock fragment ejections. Additionally, the appropriate support scheme comprised of Weldmesh, Fibrecrete, static (split set) and yieldable (Kinloc) reinforcements is recommended and implemented. Thereafter, the bolt’s efficiency is evaluated based on the axial force and elongation capacities and then compared with the published bolt performance data. The evaluation results show that the maximum bolt axial force (0.1 per cent) and elongation (0.006 per cent) are below the designed capacity and rupture strain.

Nov 29, 2022

The continuous casting of zinc alloys has been of fundamental importance for many years in the production of a number of products, including sheet for architectural applications, battery cans for dry cells and wire for metallising. The intrinsic benefits of continuous casting, including efficiency and high tonnage capability, uniformity of metallurgical structure and properties, and absence of voids and other defects, have contributed to the success of these products. Less well known, but of growing importance, is the more recent application of continuous casting technology to the production of zinc alloy bar stock products, including bearing stock, machining bar stock, forging stock and cathodic protection anodes. A wide range of zinc alloys are now continuously cast in a variety of cross sectional shapes and sizes to suit the diverse characteristics of these products. Of particular significance are the introduction of hollow zinc-aluminum bearing stock, and the availability of zinc alloy machining bar stock for hydraulic applications and for producing prototypes of zinc alloy pressure die castings. In addition to the traditional benefits, continuous casting provides special properties which are important in the application of these bar stock products. The list of successful applications of continuously cast zinc alloy bar stock is growing rapidly, and the market potential for resultant new zinc applications appears to be significant.

Jan 1, 1993

By Perring CS, Barnes SJ

The nickel exploration boom of the late-1960s and early-1970s led to the discovery of numerous komatiite-hosted nickel sulphide deposits, associated with variably serpentinised bodies of olivine-rich cumulates. Subsequent research has shown the importance of volcanological processes to understanding the genesis of these deposits. Crucial developments have come through consideration of the fluid dynamics of magmas and magma-crystal mixtures, through observation of the dynamics and geometry of modern day basaltic lava flows, through application of theory and experimentation on the kinetics of crystal growth from magmas, and most importantly from extensive detailed field mapping of komatiitic sequences in the Yilgarn Block and elsewhere. From these studies has emerged a new integrated view of the volcanological setting of komatiite-hosted deposits, and a recognition that a complete continuum of deposit types exists. Nevertheless, komatiite associated magmatic nickel deposits generally fall into two overall types based on the nature of the sulphide ore. In the first type the bulk of the ore is either massive Fe-Ni-Cu sulphide or a variable mixture of massive sulphide and an ore characterised by olivine crystals in a continuous matrix of sulphide occupying between 30 and 75 per cent by volume of the rock (called Matrix Ore). Nickel grades of massive sulphide ore range from 2 - 20 wt% and those of the matrix ore generally fall in the range 1 - 5 wt% (average 2.5 wt%) Ni/Cu ratios of the sulphide fraction are generally >10.

Jan 1, 1996

By D P. Murphy, R F. Dewhirst

Traditionally closure has been seen by the Resource sector solely as a green or an environmental issue, focused primarily on the requirement to rehabilitate the site following cessation of production activities. In addition to operational, maintenance and production aspects of processing plant design, future design teams will need to take a more holistic view and consider an increasing number of sustainability issues including safety in design and cleaner production as well as closure itself. Sustainability principles being adopted by industry such as the Minerals Council of AustraliaÆs Enduring Value Framework are now broadening our understanding of closure. While issues around the closure of tailings dams and associated infrastructure have been widely studied, few investigations have looked closely at the implications of closure on the design of minerals processing plants. It is likely that design teams may be able to make a significant contribution to meeting industry objectives by adopting innovative designs which, in addition to meeting production objectives, deliver sustainable and cost effective plant closure outcomes. This presentation explores the opportunity for innovative design of mineral processing plants through the assessment of alternative closure objectives. This assessment specifically looks at current industry standards and statutory requirements, as well as potential risks and opportunities associated with each objective. Alternative design strategies to meet these objectives are discussed.

Jan 1, 2006

Tourmaline-bearing rocks are a rare rock type of Suites 3, 4 and 5 at Broken Hill. Minor laminated plagioclase-quartz-tourmaline rocks occur in association with the quartz- magnetite rocks of Suite 3 with the greatest abundance of tourmaline-bearing rocks present in Suite 4 intimately associated with lode horizon, scheelite mineralisation and zinc mineralistion - all approximate strike equivalents of the Broken Hill Pb-Zn-Ag deposit. Bedded quartz-tourmaline rocks, tourmalinites, tourmaline-rich pelite and tourmaline-bearing lode horizon have been recorded from suite 4. The bedded tourmaline rocks rarely display cross bedding, graded bedding, slump structures and small scale intraformational breccias. Minor tourmaline-gahnite-bearing pelites are present in Suite 5. The sedimentary structures, metamorphic textures, the stratigraphic position of the tourmaline-rocks and the presence of quartz-tourmaline-gahnite-spessartine (-fluorapatite) lode rocks indicates that the mineralisation at Broken Hill and the tourmaline-rich rocks are all products of submarine exhalative hot spring systems which were most active during deposition of Suite 4 rocks. Tourmaline is chemically different from that associated with granitic activity and from other submarine exhalative tourmaline-rich rocks because the premetamorphic alteration at Broken Hill involved addition of Fe, Ti and F and subtraction of Mg - a feature reflected in the chemistry of tourmaline from Broken Hill.

Jan 1, 1983

Located 350 km west of Sydney and 20 km outside Orange, NSW, lies the Ridgeway Gold Mine û NewcrestÆs flagship Underground Gold Mine. Key to success at Ridgeway has been the fast tracked development of the 3.8 km, 1 in 5.3 conveyor decline which houses the 850 t/hr conveying system feeding the dedicated Ridgeway Concentrator, built adjacent to the existing Cadia Hill Concentrator. Eroc was contracted to develop the steep conveyor decline, drawing on its personnel and experience from past metalliferous, tunnelling and coal mining projects to complete the ambitious schedule within 12 months. This paper deals with the complexities and experiences in safely delivering what is understood to be one of AustraliaÆs steepest declines of any substantial length in a metalliferous mine.

Jan 1, 2002

As the Mount Morgan electrolytic chlorine plant is the first of its kind installed in Australia, and as the details of this method of producing chlorine have, up to the present time, been kept more or less secret all over the world, the author trusts that this paper may fill a gap in the technical literature of the subject.When an electric current is passed through a strong solution of sodium chloride the following reaction takes place -2 NaCl + 2 H 20 = 2 NaOH + C1 2 + H 2 Chlorine gas is liberated at the anode or entering pole of the current, while caustic soda and hydrogen are formed at the cathode or leaving pole of the current. If the two electrodes be simply immersed in a vessel containing salt and the current be turned on, there will be no result save slight smell of escaping chlorine gas. The passage of the current will have certainly split up the salt water according to the above equation, but as the products would be in juxtaposition they would immediately reunite, and the electrical energy would have been spent without any beneficial result having been obtained. Therefore, the all-important problem in designing an electrolytic chlorine cell is the finding of some effective means of isolating from each other the chlorine and caustic: soda as soon as liberated from the...

Jan 1, 1911

By M Barley, C A. RosiFre, L Lobato

The Carajßs iron ore deposits contain approximately 17.5 billion tons of ore with >64 per cent Fe and occur in the eastern part of the Amazonas Craton. They are hosted by jaspilitic banded iron-formation (BIF) of the Carajßs Formation which, together with metavolcanic rocks, comprise the ~2.75Ga Grpo Parß Group of the Itacai·nas Supergroup in the ~1000 km long, E-W trending Carajßs Synclinorium. The Carajas Formation comprises discontinuous layers and lenses of partly dolomitised BIF (17 - 43 per cent Fe and 35 - 61 per cent SiO2) and lenses of high-grade iron ore, cut by mafic sills and dykes. The high-grade iron ores occur as large tabular bodies of friable (soft) hematite with smaller lenses of hard (compact) hematite. The hard hematite ores typically occur at the contact with the underlying volcanic rocks and are surrounded by an aureole of hydrothermal carbonate alteration. BIF that has been overprinted by dolomite and magnetite crystallisation has recently been discovered at depth in the N4E Mine. With increasing amounts of carbonate, the original lamination (microbanding) and other fine primary structures in the BIF have been progressively obliterated resulting in alternating carbonate and iron oxide mesobands. The friable hematite ore that is characteristic of the Carajßs deposits results from ongoing weathering and leaching of the carbonates from this type of altered BIF. The hard hematite ores probably result from more extensive early oxidation. The association of both carbonate-altered and jaspilitic BIF with the N4 Mine is similar to that observed at the Mount Tom Price deposit in Western Australia, where carbonate-altered BIF occurs below massive hematite ore with a jaspilitic halo developed above the orebody. This indicates that as at Mount Tom Price, hydrothermal carbonate alteration and associated loss of silica from BIF may be an important step in the formation of these giant hematite deposits.

Jan 1, 2002

By D Goel

India, the second-largest steel manufacturer globally, achieved crude steel production of around 126 million tonnes (Mt) in the last financial year of April 2022 to March 2023 (FY23), against an installed capacity of 162 Mt. In its National Steel Policy, 2017, India has undertaken targets to take the crude steel production capacity to 300 Mt by 2030–2031 and production and demand to around 255 Mtpa, also by this deadline. The blast furnace-basic oxygen furnace (BF-BoF):electric arc furnace-induction furnace (EAF-IF) ratio in 2022 was at 44:56.

Sep 18, 2023

By G Bignall, I Chambefort, A B. Christie, A J. Rae, M P. Simpson

"An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation. Key indicator hydrothermal alteration minerals formed from fluids of known fluid composition (neutral versus acid pH) and temperature have been mapped for New Zealand (NZ) geothermal fields by visible/near-infrared (VNIR) and short wave infrared (SWIR) reflectance spectroscopy. Smectite, interstratified illite-smectite and illite formed from neutral pH fluids have zoned distributions with higher temperature illite (&gt;220ºC) in and around the upflow of chloride waters and low temperature smectite (&lt;150ºC) on the margins (eg Ohaaki, NZ). In adularia-sericite epithermal deposits, Au-Ag veins are similarly surrounded by zoned clays, with mineralised veins enclosed by illite (eg Martha, NZ) or occurring at the illite/illite-smectite boundary (eg Favona, NZ). Reflectance spectroscopy is also highly effective in identifying minerals formed from acid fluids; both steam-heated acid-sulfate waters (eg kaolinite and alunite at Rotokawa, NZ), or magmatic-hydrothermal fluids (eg pyrophyllite and topaz at Ngatamariki, NZ). These same alteration minerals commonly show zoned distributions in high sulfidation epithermal deposits (eg Rodalquilar, Spain) and in lithocaps associated with porphyry deposits (eg Lepanto, Philippines). Thus reflectance spectroscopy permits the rapid identification of key alteration minerals that can be mapped at a high sample frequency and used as vectors towards mineralisation.CITATION:Simpson, M P, Bignall, G, Rae, A J, Christie, A B and Chambefort, I, 2015. Mapping hydrothermal minerals in New Zealand geothermal fields using reflectance spectroscopy (VNIR-SWIR) and application to mineral deposit exploration , in Proceedings PACRIM 2015 Congress, pp 243–248 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 18, 2015

By C Fountain

Australian mining and engineering companies have increasingly been investing in the mining industry in Brazil. It is a country of enormous mineral and agricultural wealth, with a well-established mining sector. Some Brazilian mining companies and personnel have been journeying in the opposite direction. There are significant differences in the approaches to engineering between the Australian and Brazilian industries that can cause confusion for companies operating in the other country. These range from differing expectations during the various stages of feasibility studies to style of plant and contracting strategies during the construction phase of projects. Some of the differences are driven by tax regimes, labour costs, or different settlement patterns. Others are the result of different histories and pressures on the industries in the two nations.This paper describes some of the differences in approach found in the two countries and some of the reasons for them.

Aug 8, 2011

By D Connelly

Magnetite orebodies generally means mining lower grade iron ores, crushing and grinding with significant energy costs in processing and the capital costs being significantly higher than for direct shipping ores (DSO). Overseas, the mining and processing of magnetite ores has a long history of production due to the lack of DSO deposits. This raises the question as to why the new magnetite projects have been so problematic and also whether there is a future for the long list of potential magnetite projects in Australia.The quality of the magnetite concentrate product is superior to most DSO products and the magnetite contains energy benefits when converted to hematite in sintering or pelletising. The industry’s hopes for new projects have been dashed and questions are being raised as to the financial viability of such projects.A comparison of Grange Resources Savage River, Arrium’s Project Magnet, the Sino Iron Project and Gindalbie’s Karara Iron Project is used to understand the differences between the projects and why some are more successful than others.CITATION:Connelly, D, 2015. What is the future for magnetite projects in Australia and why have some of the new projects been so problematic?, in Proceedings Iron Ore 2015, pp 107–114 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 13, 2015