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The paper describes the geology, structure, stress, gas and strata geomechanical properties for Leichhardt Colliery and their reactions to mining.

Jan 1, 1986

Optimisation of the Advanced Automation System at Inmet Mining's PyhSsalmi Mine, Finland

Sep 13, 2010

By Gross A. E, Neville P. C

Over the last decade heap leaching with a cement binder has allowed the economical leaching of low grade gold ores of less than 2 grams/tonne. Despite the continued use of cement as an agglomeration aid, numerous leaching operations continue to experience channelling and blinding problems. This paper describes the development of polymeric agglomeration aids, Extract Ore 9760 and 9960, which when used as a partial cement or lime replacement can result in a higher rate of and/or a higher total gold recovery in plant evaluations. Extract Ore in combination with cement acts to produce a stronger agglomerate which results in reduced fines migration during leaching and helps prevent blinding of the heap. Both of these changes will give a more even flow of cyanide solution throughout the heap and improve solution contact efficiency within the ore. Polymeric agglomeration aid programs are now being used by heap leaching operations in three different countries. A summary of benefits identified at some of these operations are presented in this paper.

Jan 1, 1994

LESLIE BRADFORD GOLDEN JUBILEE ORATION "Not only a metallurgist but a scientist of the highest order" Leslie Bradford and the Australian Metallurgical Industry

Jan 1, 1987

By Mroczek C. R, Evans D. A

Renison is a world-class ore deposit that has been mined for over 100 years. It currently has reserves of 5.06 Mt @ 1.88 per cent Sn and a projected mine life of 8.5 years. Recent advances in the geological understanding of the deposit have been associated with detailed structural and geophysical investigations accompanied with the discovery and exploitation of the Rendeep orebodies. Mineralisation is linked to the forceful emplacement of the Devonian Pine Hill Granite that resulted in a complex brittle (-ductile) deformation of the Eo-Cambrian host stratigraphy. Dilation jog development on the Federal-Bassett Fault in the Federal and Rendeep areas provided access for cassiterite-rich magmatic hydrothermal fluids responsible for carbonate replacement Mineralisation.

Jan 1, 1997

Revised throughput rates, as a result of current mining methods and tight controls on mine dilution, have dictated a change in metallurgical philosophy at Renison Limited. Emphasis on throughput capacity increases has altered to a reduction in circuit complexity and operating costs. Extensive surveys of the gravity and cassiterite flotation circuits led to several plant modifications between August 1989 and March 1990. The coarse and fine gravity retreatment roughing tables were by-passed, the coarse gravity retreatment roughing tables were re-commissioned, the cassiterite flotation rougher capacity expanded and the gravity regrind cyclones re-configured.

Jan 1, 1991

By Preston JC, Richards DJ

A multicommodity exploration programme was mounted in the 1970s by CRA Exploration Pty. Limited over a major part of the southern Murray Basin in Victoria. Commodities sought were brown and black coal, gold, uranium, diamonds, titanium and zirconium rich heavy minerals, and base metals. An area of 40 000 km2 was held under exploration licences by the Company. Exploration techniques used were literature research, airborne magnetics and gamma ray spectrometry, drilling, and geophysical well logging. Targets were defined in both the Tertiary basin sediments and the underlying Palaeozoic sedimentary and igneous rocks. Although exploration is continuing, large resources of brown coal and low grade titanium rich heavy minerals have already been discovered. Exploration for uranium was abandoned in accordance with statutory requirements. The search for significant resources of the other commodities has not been successful.

Jan 1, 1986

By Askew JE

The large, massive low grade gold orebody at Mount Charlotte has demanded an innovative approach to mining engineering. In the last five years several advances occurred in the areas of rock mechanics, mass blasting, blasthole drilling and truck haulage.Successive crown pillar failures throughout the life of the mine had resulted in a continuous geotechnical program, mostly utilisingconsultants. The culmination of this workwas the development of a successful crown pillar support system. Several stopes have incorporated the technique and the most notable success has been the relatively large F3 crown pillar.In hole hammer drilling was introduced to the mine in 1979, but little work had been done to develop a blasting system to suit the 165mm diameter holes. A non-electric sequential blasting system was adapted for use at themine and up to 600,000 tonnes have been fired successfully in an individual blast. Problems with ground vibration were addressed although this work remains incomplete.

Jan 1, 1984

By Selischop F, Tredoux M

The distribution of platinum-group elements (pGEs) has been investigated in matte and slag samples from Waterval Smelter (Rustenburg Platinum Mines). The study showed that a strong preference of PGEs for alloy phases in matte represents a concentration mechanism that commenced in the furnace but can be considered a continuum from natural processes. Metal losses to fayalite (converter) slag occur by matte entrainment due to the mechanical capture of liquid sulphide droplets from the matte layer, and the exsolution of dissolved metal sulphide resulting from changes in the oxidation state of the slag. The latter is comparable to immiscible sulphide in basic magmas. However, the observed distribution of PGEs shows enrichment in metal phases of the matte. A mechanism is proposed whereby naked PGEs in silicate melts coalesce to form clusters which are stabilised by surface attachment of sulphur atoms. This envelope acts to 'draw the cluster into sulphide melts. Small particle melting effects permit PGE clusters to remain as liquids at magmatic and smelter temperatures.

Jan 1, 1994

By L Blackwell

Strategic mine scheduling is an industry best practice for increasing the long-term value of mining operations and supply chains. The application of optimisation technology such as mixed integer linear programming (MILP) is able to achieve a mathematically optimal result for a given scheduling model. Such a model will typically define the available source material, processing options and desired constraints for accessing and processing the material. Most strategic scheduling models, however, do not include a sufficiently detailed model of capital expenditure options related to capacity expansion.Typical strategic schedule models do not include important capital expenditure features such as capacity decay or expiration (limited lifespan of trucks), precedence relationships over time (rail construction before a new plant or non-linear expansions due to economies of scale) or mutually exclusive option sets (choices of plant size). By not including these features, a strategic mine scheduling model for a capital-sensitive operation is unable to be optimised to deliver maximum value or profitability.This paper presents several results of MILP optimisation using advanced capital expenditure modelling for mining operations and supply chains. Results of the study demonstrate that optimising capital expenditure at the same time as optimising the mining schedule allows for minimisation of capital purchasing, optimal timing for those purchases and optimal scheduling around them. Overall, this results in an increase in net present value.CITATION:Blackwell, L, 2014. Capital expenditure modelling for strategic mine scheduling, in Proceedings Orebody Modelling and Strategic Mine Planning Symposium 2014 , pp 315–322 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 24, 2014

Coal seam methane (CSM) is an æunconventionalÆ gas resource that is becoming an important energy resource for Australia, especially along the eastern seaboard. It has been conventionally believed that methane in high rank coals was exclusively derived from thermocatalytic processes during decomposition of coal at elevated temperatures. However, recent re-interpretations of gas composition and isotope data have indicated that microbial methane generation may be one of the main processes responsible for the accumulation of commercially producible methane in some coals. In low rank (æbrownÆ and sub-bituminous) coals, methane (CH4) is mainly generated by microbial activity at low temperatures. The amount of this biogenic gas generated and accumulated in low rank coals depends largely on the rate of burial and depth. Most low rank coals are æunder-saturatedÆ with respect to their maximum gas sorption capacity. In contrast, high rank coals may be highly saturated due to extensive gas generation from both thermogenic and secondary biogenic processes. However, in basins where secondary biogenic gases have not replenished the thermogenic gas lost during basin uplift, the coals will be æunder-saturatedÆ. In many basins around the world, high CSM producing zones appear to contain secondary biogenic CH4 generated by microbes transported in meteoric water recharge through permeable coal seams. Biogenic CH4 generation requires the activity of a consortium of anaerobic respiring microorganisms, fermentative bacteria and acetogenic bacteria to break down complex organic molecules to simpler molecules having one or two carbon atoms, which enables methanogenic archaea to generate CH4. The two main methanogenic pathways in the generation of secondary biogenic gas from coal are aceticlastic reaction and carbon dioxide (CO2) reduction. In eastern Australian coals CO2 reduction appears to be the main process. The types of microbes that are directly involved in these processes are unknown because they have not yet been isolated from the coal seams. The CSIRO is currently investigating the processes of biogenic gas generation in Australian coals. Potential may exist to introduce appropriate microbes into deep coal seams to enhance methane saturation levels, gas sorption capacities and permeabilities.

Jan 1, 2004

By Penttila V

The Paleoproterozoic Hitura Ni-Cu deposit in western Finland is in an ultramafic igneous complex composed of two subvertical plug-shaped bodies embedded in intensely migmatised felsic gneisses. The ultramafic complex is not far from a north-south trending graphitic and sulphidic gneiss zone interpreted to be a primary sulphide-graphite unit in the metasedimentary sequence. The sulphide accumulation exists as a zone parallel to the contact of the northern ultramafic body. The ultramafic rock types, now mainly serpentinites, have primarily been olivine adcumulates in the core grading to olivine orthocumulates and pyroxenites towards the margins. Coarse-grained felsic pegmatite veins injected serpentinite where they now exhibit prominent zoned alteration rims of chlorite, antophyllite and talc. The serpentinite core of the body was primarily an olivine adcumulate derived from a tholeiitic or high-Mg basalt parental magma with about 11 wt % MgO. Metamorphism and alteration have totally changed the igneous mineral compositions and the rock types are serpentinites (from olivine adcumulates), ambhibole-bearing serpentinites and amphibole-chlorite rocks (from pyroxenites). As the result of CO2 alteration talc is an accessory mineral throughout the serpentinite. Like silicates, also sulphide minerals are altered. In the core of the body the low-grade sulphide dissemination still reveals primary igneous interstitial forms. The core sulphides are now mackinawite, pentlandite and valleriite instead of primary igneous pyrrhotite and pentlandite derived from Mss. At the marginal zone the heavy dissemination and net-textured sulphides display pyrrhotite-pentlandite-magnetite intergrowths with magnetite films along cleavage of sulphides, mackinawite in pentlandite and exsolution textures of different low-temperature pyrrhotite phases as the result of alteration processes. Mechanically weak rocks, complicated structures and textures of the ore, magnetite and mackinawite intergrowths in pentlandite and readily-floating MgO silicates cause problems in exploitation of the deposit. Solution to problems come from selective stoping, three-step classification in grinding, froth-washing technique and on-line process control based on ore type determination from process data using an expert System

Jan 1, 1996

By S J. Schafrik, Z Agioutantis, E C. Jong, K Luxbacher

Real-time monitoring of mine operating parameters is available at most mines. However, access to these data for an individual operation is typically underutilised by mine managers and technical personnel. Such monitoring systems are typically designed to provide data streams and alarms to a responsible person, but they are not utilised to extract underlying trends or correlate different data groups. Furthermore, multiple monitoring systems are usually implemented at a given site without interconnection between vendors’ systems or connection to any central management, and mine personnel are only exposed to a minimal subset of such data. Thus, it is not easy to analyse and correlate individual data streams and generate information to enhance day-to-day operational decision-making and improve safety and efficiency.This paper addresses the primary challenges associated with centralising data management and effecting greater utilisation of the vast amount of collected data, while at the same time reducing the time and effort required to manage such large data sets. Furthermore, it presents the conceptual design of a database application that can organise, present and analyse data collected by multiple sensors in different environments. The database is designed to operate in a passive manner so that active mine data management systems are not impacted. An example is given where this database is used for managing atmospheric data collected at an underground coalmine operation in the US. These techniques have a universal application and can be incorporated in a wide range of mining and construction projects.CITATION:Agioutantis, Z, Schafrik, S J, Jong, E C, Luxbacher, K and Karmis, M, 2015. A platform for managing and analysing atmospheric data in underground coalmines, in Proceedings Third International Future Mining Conference, pp 3–10 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 4, 2015

By A D. Wulfse, C M. D Barton

Underground fractured aquifers in the Ernest Henry deposit are to a large extent controlled by deposit scale brittle structures. The underground mine has been subdivided into nine water zones based on hydrogeological characteristics, including conductivity and connectivity, within the mining areas bound by these structures. The nine water zones and the hydrological characteristics of the associated structures are utilised for risk assessing mine development and for targeting diamond drilling dewatering activities. Wireline and conventional underground diamond drilling techniques have been used throughout the network of underground aquifers with the aim of dewatering areas within the mining footprint. These dewatering drilling campaigns have historically been highly successful at lowering aquifer water levels throughout the underground workings. As part of recent mine expansion activities, diamond drilling has intersected high pressure (>507 psi), high temperature (>50°C) and high flow water (>3 L/sec) in as yet unconstrained underground aquifers. Groundwater is typically conducted through rubble and clay rich faults, further hampering progression of drilling. Drilling through fractured aquifers at depth presents both mine planning as well as safety challenges. Recent drill holes have been delayed or abandoned when aquifers hosting this high pressure, high flow water have been intersected, risking mine planning deadlines. Recent technological innovation developed to control groundwater outflows from the diamond drill hole whilst drilling has been trialled at the Ernest Henry Mine. This case study focuses on the utilisation of alternative drill methodologies to allow the current drilling campaign to continue without delay, whilst also improving safety conditions encountered on the drill site.

Mar 22, 2022

By Stewart WJ

Australia's first offshsore well was spudded in on 27th December 1964 and resulted in the discovery of the Barracouta gas field. Further exploratory drilling led to the discovery of the Marlin gas field in December 1965, the Kingfish oil field in April 1967 and the Hblibut oil field in June. 1967. In September 1968, a small oil reservoir was found in a sand below the main Barracouta'gas reservoir. The Snapper gas field was discovered in May, 1968 Information on exploration activities associated with the discovery of oil and gas in the Bass Strait area may be found in the paper, "Exploration in the Gippsland, Bass and Otway Basins, Australia" by B. M. Hopkins. _ Development of the commercial fields is being undertaken on an equal participation basis by Hematite Petroleum Pty. Ltd. and Esso Exploration and Production Australia Inc. Esso Standard Oil (Australia) Ltd. is responsible for the design, construction and operation of the production facilities.

Jan 1, 1970

IT is very difficult for a founder engaged in jobbing work, comprising all sizes and classes of castings, to appreciate that the analysis of the iron he is using cannot entirely fill the situation he desires for his varied classes of work. Neither is there any panacea in the shape of an iron mixture that will suit the whole of his floor for the day.From his own experience he generally alters his cupola charges during the cast, endeavouring to meet at the same time the requisite metal composition for the castings he is about to pour.The founder on repetition work is in a much better position to stabilise his methods, arrive at a certain pig-iron' analysis, regulate...

Jan 1, 1926

By A E. Annels, M D. Raine, I M. Platten

Lode-gold systems are often characterised by a high to extreme nugget effect (>50 per cent), and the presence of coarse gold particles (>100 ¦m in size). They rank amongst the most difficult of ore deposits types, in terms of producing an accurate and precise resource estimate. Their effective sampling is generally difficult because of the relatively low concentrations involved and erratic nature of the gold particles. Grade continuity is usually less consistent than gross geological continuity, and is typified by the localisation of grades within discrete oreshoots. In most cases drilling, particularly diamond drilling is an effective measure of global geological continuity, whereas grade can only be reliably resolved from underground development. Depending upon drill density and geology, it is unlikely that anything above an Inferred Mineral Resource can be estimated from surface drilling alone. Underground development, in-fill drilling and, potentially, bulk sampling or trial mining will be required to delineate Indicated and Measured Mineral Resources and subsequent Ore Reserves. Grade estimation will have to account for highly skewed and often multi-modal populations, extreme values, a high nugget effect and low geostatistical ranges. A clear geological model that honours both geological and grade continuity must drive the resource estimation process.

Jan 1, 2003

Underground space can be defined as space below natural ground level which can be used as an alternative to an above ground location. While many of our above ground structures inherently involve underground excavation for foundations and services, the term underground space specifically refers to organised development of underground openings and of the underground domain. For example, the services to a city such as power, gas, sewerage, water and communications are installed in a congested array which usually requires roads to be dug up when the services need to be accessed. An underground space installation of services would involve a well planned conduit which is easily accessed without any excavation. The concept of using this virtually untapped land resource to the advantage of our expanding cities is gaining considerable interest in Australia. Overseas, in the Scandinavian countries and some Asian countries, underground space has been used for centuries; in Great Britain, France and the United States of America over the last century and in Japan for over a decade. This paper focusses on the types of underground space usage which should be competitive with above ground use and suggests areas in which the competitive edge may be improved in favour of underground space. In particular, considerable advantage is seen by using well-planned underground space developments in major cities, where the strategic central location of the development takes advantage of proximity to potential users. However, the largest single factor affecting the acceptance of underground space is the high capital cost of construction, even though an underground space development may result in lower operating costs and reduced long-term maintenance costs. While excavation methods and associated costs are very much site-specific, the importance of applying the latest technology in rock breakage, with consideration of ground vibration, excavation rates and ground support, remains a major challenge to the development of underground space.

Jan 1, 1995

In June 1992, the High Court of Australia recognised native title of the Meriam people over parts of the Mer Island in the Torres Strait as a form of common law. The Court also indicated that native title may have survived European settlement of the mainland Australia where it had not been extinguished by Governments and Aboriginal people have maintained their traditional connection with the land. The decision meant that two systems of land law were seen as existing side by side in Australia: ò one which derived from grants from the Crown under laws passed by Parliament; ò another which derived from the diverse laws and customs of the many Aboriginal groups in Australia.

Jan 1, 1996

This paper briefly discusses the negotia- tion of the more important provisions in agree- ments for exploration and mining rights with Pacific countries. LAND RIGHTS Land rights are complicated and sometimes controversial in many of the Pacific countries. In some countries, a company will have to deal with land owners directly; in others, the government will act as intermediary. Inevit- ably, a company will have to deal with both. Mining companies need to be sensitive to the culture and particular interests of the land owners and of their history in defending their rights. The issues are too complicated to be dealt with here. Some mining companies have spent, and will continue to spend, considerable time trying to understand them. It will " require patience, perseverance, sensitivity and unflagging optimism. The better advised companies will ensure that their local repre- sentatives get to know the land owners, under- stand their concerns, and will pursue a policy of keeping them informed on a regular basis of all of the company's activities and proposed activities. Good community relations are the keystone for good mining operations in the Pacific. Most countries will require the submission of an environmental impact statement so that they will know in advance what effects a pro- posted mining operation are expected to have on the environment and how it is intended to deal with them. They will also want to approve the company's environmental reclamation and rehabilitation plan. Let's face facts right away - mining, by its very nature, is not going to improve the environment. There will be waste discharges, emissions and deposits. They will affect the land, air and water and hence human, marine and animal life and vegetation. There will be sounds and odours and the esthetics of mining operations, though perhaps pleasing to geolo- gists and mining engineers, will not please Others.

Jan 1, 1987