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By M A. Ward

On 23 May 1977 the Hon Mr George Gair announced an amalgamation of the present Ministry of Energy Resources, the New Zealand Electricity Department and the Mines Department. Hopefully it will prove to be the solution of many national problems in energy planning and policy making, in energy distribution and use, and energy discovery and production. The name of this new giant is the Ministry of Energy which gives a firm indication of its future direction. For those amongst us involved with mineral energy resources the establishment of this new department must be encouraging. For those amongst us who are involved in non-energy side of the mineral industry it is the very opposite. The loss of the Mines Department a year short of its centenary is a loss for the mineral industry without a doubt - but how much of a loss?

Jan 1, 1977

ICI Australia has been developing PC-based software to assist the blast engineer to design and monitor open pit blasts. The scope of this software differs significantly from commercially available mine design packages.The software is designed for routine use in a normal production environment. The system enables the engineer to produce practical documents which include: a drilling plan, a loading sheet, a hook-up diagram, an inventory of explosives and auxiliary items, and other data on the blast such as tonnages and powder factors.

Jan 1, 1992

The structure and tectonic setting has had a strong influence on gold mineralisation at the Porgera gold deposit. Here, the structural controls on the mineralisation at Porgera are discussed and placed in a regional tectonic context. The Porgera gold deposit is related to the emplacement of the Porgera Intrusive Complex. Prior to intrusive emplacement at Porgera, Papua New Guinea was affected by a major fold and thrust episode which occurred in response to arc-continent collision in the Late Miocene. After crustal shortening the region experienced a relaxation of compression which is expressed in the deformation accompanying mineralisation at Porgera. The first stage of mineralisation (stage I) is hosted by extension fractures, and is spatially associated with exposed intrusive stocks. A later episode of mineralisation (stage II) is hosted by the faults and fractures of the Roamane Fault Zone, which was active as a dip-slip normal fault during stage II mineralisation. Therefore a change in the tectonic environment from shortening to extensional tectonics can be seen at Porgera before and during mineralisation. Rapid fault-slip during stage II mineralisation may have aided high-grade gold mineralisation by subjecting hydrothermal fluids to changes in pressure, temperature, fluid-fluid and fluid-rock interaction. Uplift to form the highlands of Papua New Guinea occurred after mineralisation and was largely complete by 4.0 Ma.

Jan 1, 1995

Mine planning is difficult. Even for small operations, it involves reasoning with complex variables and the practical difficulties of mining. It is also about predicting and planning the future in an unpredictable physical and economic environment. Yet we rely on a handful of individuals and their spreadsheets to tell us how to do it û planning the business and activities of mining to hopefully produce results that will please stakeholders. Does it work? Not as well as it could. Planning affects everyone in the organisation. Company executives are demanding more reliability and stability in cost and revenue forecasts from their operations. Management want to explore ways of being more cost effective. Miners and contractors want more useful plans and realistic targets. And the planners have to describe the method that will translate business objectives into implementable plans. Even with the use of computer technology a lot of effort is expended to produce plans that are largely qualified by the level of knowledge and experience of individuals. Better use of information and the application of Intelligent Technologies can improve the quality and reliability of mine plans and schedules. By capturing the knowledge within the organisation and speeding up the planning process, Intelligent Technologies allow more options to be considered more rigorously. But it is not just about technology. It is about how technology is implemented and embodied in the way the business is managed for performance. When this happens, the real benefits of better planning start to flow.

Jan 1, 2003

The published safety policy of Mount Isa Mines Limited, together with details of the organisation and control techniques adopted by management to pursue an active safety programme within the company, is presented. The importance of communication by management through the organisational hierarchy and procedures instituted to ensure rapid and concise feedback on safety concerns are detailed. The paper also describes the role of the occupational health department and safety committees in assisting management to monitor the safety effort of supervisors and employees. Current safety performance levels are tabled together with details of some aspects of the programme on which safety effort will be concentrated in the future.

Jan 1, 1975

By Getliffe RK

It is becoming more and more difficult to operate mineral and metal processes profitably, as operating costs rise, quality demands in-crease, international competition becomes more fierce and Government charges remain at their current levels. Profitability today depends upon efficient operations, which can only be achieved through precise and dependable con-trol of each process unit comprising thetotal plant.Modern process control systems utilise distributed architecture with microprocessor-based controllers, data acquisition devices and VDU operator stations. Honeywell intro-duced this control technology in 1975 with the "Total Distributed Control" System. Now, building on the proven performance and re-liability inherent in TDC hiway modules, Honeywell has extended the TDC system to inte-grate both management information and control by providing distributed processing modules on the new TDC 3000 Local Control Network (LCN).

Jan 1, 1985

By Zhou A, Cadogan J. M

Direct reduction of iron ore (DR) is one of the promising technology emerging in the world's steel industry. Kinetics and Mossbauer studies of DR with hydrogen have been carried out at two temperatures of 600¦C and 800¦C in this investigation. The results show that different controlling steps govern the reduction rate at different temperatures. The mechanism was also found to vary during the reduction. The Mossbauer spectra of the samples reduced in various time intervals were studied to determine the phase changes during reduction.

Jan 1, 1997

By Coates J. R, Firth I. C

The Imperial Smelting Furnace at Cockle Creek, NSW, was constructed in 1961 and is the oldest facility using the Imperial Smelting process in operation. In recent years there have been significant improvements in many areas of the operation, including production, safety, hygiene and environmental performance. Steps taken to achieve these improvements are described. Plans to secure a profitable future while meeting environmental requirements are outlined.

Jan 1, 1993

Managing project exposure and risk has numerous viewpoints, including those of engineers, owners, bankers and insurers. Fewer stakeholders are involved in early stages, though with wider risk management techniques and tools available. The costs and sometimes benefits of the occurrence of risk and uncertainty have different contingent outcomes for different stakeholders. For some, the impact of risk outcomes can be mitigated or managed. Some sectors and stakeholders can manage resources project risks more completely, by choice or by externally imposed forces, opportunities and constraints. The core to resources project risk management lies in the identification and analysis of project risks, the examination of project management risk options and alternatives, and the determination of which risks are able to be controlled, managed or laid off to third parties. Without prior risk identification and knowledge, the wildcard of previously unidentified or unconsidered project risk impact has the potential for fatal impact to one or more stakeholders. A range of case studies is reviewed, from exploration projects to development and operating projects, with relevant learning experiences, from the risk management lessons available from the oil and gas sector as well as the mining sector. For many cases, the emphasis focuses on the risk analysis modus operandi and on risk management and risk mitigation techniques that can be and in some cases have recently been implemented for resources project and related debt, capital markets and equity project fundings.

Jan 1, 2003

Electromagnetic methods used in geo- physical prospecting for conductive ore bodies have proved successful in Canada,Sweden and other countries. In Australia however the depth of weathering generally exceeds 30 metres. This introduces a problem of highly conductive overburden and renders equipment useful elsewhere virtually ineffective. A discussion of several EM prospecting techniques is presented and a new system under development at James Cook University using V.L.F. transmissions capable of indicating changes in impedance (not only highly conducting media) is outlined.

Jan 1, 1974

By Blom MS

Two well-developed styles of mineralization occur in the Nevados del Famatina mining district, Famatina ranges, La Rioja province, Argentina. Porphyry molybdenum- copper-gold mineralization and high level acid sulphate alteration/mineralization (Nevados del Famatina) are related to intrusion of the Pliocene Mogote rhyodacite porphyry complex. High sulphidation epithermal mineralization (La Mejicana) is developed peripheral to the Nevados del Famatina deposit. Both are hosted mainly by the Ordovician Negro Peinado metapelites.At Nevados del Famatina, five mineralized fracture events have been identified and correlated with four distinct alteration assemblages. Stage I (barren quartz) and stage II (molybdenite¦sphalerite¦pyrite) mineralization are associated with a K-silicate alteration assemblage of K-feldspar+biotite+quartz+magneti te¦ilmenite¦anhydrite. Stage III (bornite+pyrite+sphalerite+molybdenite ¦chalcopyrite¦idaite) and stage IV (chalcopyrite+pyrite +sphalerite+gold¦tennantite-tetrahedrite) mineralization are related to a quartz-sericite assemblage of quartz +phengite+illite+pyrite+rutile. Stage V mineralization is divided into two substages. Stage Va (chalcopyrite +pyrite+sphalerite¦ tennantite-tetrahedrite ¦ tellurides ¦ gold ¦enargite¦famatinite¦stibnite¦molybdenite) is related to a sericite-clay assemblage of quartz+illite+kaolinite ¦montmorillonite¦alunite. Alunite-kaolinite alteration (alunite+pyrophyllite+kaolinite+ aluminum - phosphate -sulphate minerals ¦illite¦fluorite¦corundum¦anhydrite) occurs in the upper part of Nevados del Famatina associated with the later stage Vb (quartz+famatinite +chalcopyrite+covellite + chalcocite ¦ marcasite ¦ enargite ¦ luzonite¦sphalerite¦melnikovite) mineralization.

Jan 1, 1990

By C P. Kramers

The need to provide a sufficient quality and quantity of backfill continues to increase in South Africa, particularly as related to the increasing depth of mining. More and more applications require well designed fill systems either as classified or cemented backfill, and in some applications even tailings/aggregate based backfills. The paper discusses developments in backfill technology in South Africa with special emphasis on reliable system designs and operations, particularly as related to the preparation and hydraulic transportation aspects. Approaches for the alleviation of previous problems associated with premature pipe failures in vertical shaft columns for the distribution of tailings based backfills are discussed. Resulting from CSIRÆs developmental work, reliable full-flow systems, which can operate at low system pressures, have become a common practice, provided that backfill flowrates and internal pipe sizes are well matched. This aspect is reviewed. With regard to the tailings/aggregate based backfills the paper reviews some of the results of comprehensive in situ monitoring and the development of such systems. It is shown that a thorough understanding of the effects of aggregate top size, fines content and slurry relative density is required in order to ensure the restartability of temporarily shut-down pipelines. Some innovative technologies for the comminution of development waste underground to yield aggregate products potentially suitable or hydraulic transportation and backfilling, are briefly discussed.

Jan 1, 1998

Traditional methods for monitoring, and hence controlling, pyrometallurgical processes rely heavily upon the skill and experience of operators. A skilled operator will usually achieve consistent, though often conservative, results, whilst an un-skilled operator will require considerable time and training to achieve the same results. Semtech Metallurgy AB have demonstrated that continuous and precise control of pyrometallurgical processes can be achieved through on-line analysis of pyrometallurgical flame off-gas using optical spectroscopy. The feasibility of the technology has been demonstrated on a large number of full-scale tests at production plants and by several commercial installations. Evidence suggests that installation of this technology, called Semtech Optical Production Control (OPC), has resulted in considerable economic benefits to the plant efficiency and asset life. These economic benefits are believed to be a direct result of improved objective on-line control. Technically the following benefits have been demonstrated: improved metal grade control, reduced metal losses, reduced processing time, and improved personnel safety. SemtechÆs OPC is a non-intrusive technology which relies on the fact that the composition of the vapour phase above a high temperature melt is closely related to the instantaneous status of the melt. This enables on-line real-time analysis of the furnace melt to accurately determine melt status and in particular reaction endpoints. Originally developed for on-line monitoring of copper converting in a Pierce-Smith vessel the field of applications for the technology is steadily growing. This paper introduces the Semtech OPC technology; discusses various applications and outlines the demonstrated benefits.

Jan 1, 2002

During the 20th century, the iron ore mining industries of Canada and the United States passed through several periods of transformation. The beginning of the 21st century has seen yet another period of transformation, with the economic failure of a number of steel companies, the acquisition of their facilities by more viable steelmakers, and the consolidation of control within the North American iron ore industry. Changes in Canadian and United States iron ore production and the market control structure involved are analysed. The consolidation of ownership, formation of foreign joint ventures within North America, planned divestitures of upstream activities by steelmakers, and industry changes made to ensure availability of feedstocks will be reviewed. The traditional isolation of the Canadian and United States iron ore operations and their strong linkage to downstream steel production will be discussed in the context of a changing global economy. Management-labour conflicts that have taken place and agreements made during 2000 through 2004 will be discussed in the context of the economic environment leading up to these agreements. Cooperative agreements between competing Canadian and United States companies to resolve client needs in processing and blending will be examined. A joint industry-government project designed to use new technology to produce direct reduced iron nuggets of 96 - 98 per cent iron content using non-coking coals will also be assessed. Changes in iron ore transportation methods, ownership and infrastructure will be reviewed for both rail and inland waterway transport between Canadian and United States companies. A brief analysis of social and environmental issues relating to sustainable development of the Canadian-United States iron ore industry will be included.

Jan 1, 2005

By Shining Z

The strength and deformation of more than two hundred coal samples have been tested in the condition of triaxial compression. The regression equation showing the relationship between coal strength and pressure in the pores, as well as confining pressure, was obtained. The appropriate calculation for stress-strain curve was carried out. Further, an analysis shows the variation of coal strength and its modulus of elasticity in methane medium.

Jan 1, 1992

Over the last decade mineral exploration in New South Wales has increased markedly. This is due to various factors including the influx of overseas companies an. capital, increase and stabilization of metal prices and improvements in exploration techniques. The initiation of full-scale petroleum exploration and recent discoveries of large mineral deposits in the west, north-west and north of Australia has increased overseas capital, and brought scientists and technicians into the country. Naturally there has been an overflow into New South Wales, which is less attractive as an area for new and large-scale discoveries. In some fields, rise in metal prices and price stabilization has largely contributed to the intensif- ication of exploration. Increased tin production in New South Wales since 1963 is a direct result of price rise and stabilization, and rise in the price of silver has revived an interest in silver prospecting in recent Years,

Jan 1, 1969

Almost from the beginning of civilisation the inhabitants hadlearned the art of recovering and working copper to produceitems which were of use to society.From the early beginnings of the use of copper which can betraced back 6000 years and more, there has been an evolutionaryprocess accentuated in more recent times in which the art ofproducing alloys particularly with tin and latterly zinc and otherelements, has given society a wide range of useful alloys for usein industrial, domestic and architectural applications.

Jan 1, 1995

By S C. Dominy

A high nugget effect and the presence of coarse gold characterises many vein-gold deposits. The effective sampling of these deposits is often difficult because of the relatively low concentrations involved and erratic nature of the gold. Geological complexity often compounds this effect. Underground development, in-fill drilling and bulk sampling/trial mining are often required to delineate Ore Reserves. Winzing is an historical technique that was used to gather geological and sampling data during underground exploration. It permits access to the mineralised structure below the current datum to help determine viability. Winzing has always been considered an arduous and dangerous task. Modern technology has led to the development of the Mobile Supersucker, essentially a giant vacuum cleaner. This system permits safe and efficient winzing activities, and allows the collection of bulk samples for grade estimation. Bulk samples from horizontal development have long been collected to help define mineable grade. However, when defining blocks below current development, there has been over-reliance on ineffective æsmall sampleÆ drill data. The Mobile Supersucker permits safe and cost-effective development of winzes and off-winze sublevels.

Jan 1, 2003

The various functions of public relations are playing an increasingly important part in the activities of the many companies now engaged in oil exploration in Australia.Several of the larger exploration companies, notably West Australian Petroleum Pty.Limited, Ampol Exploration Limited, Caltex Oil (Australia) PtSr: Limited and Australian Oil and Gas Ltd. (and its American Associate Union-Kern), employ staff or consultant public relations specialists. In, most of the other companies now exploring in Australia, public relations are handled within the company, directed from the highest executive level.The object of public relations in.the oil industry is. to create in the public mind an impression favourable to the industry as a whole and'the company -or group of companies with which the public relations officer is associated.

Jan 1, 1962

By Hatcher MI

Exploration undertaken at Copley diapir has located several occurrences of oxidized supergene and primary sulphide copper mineralization at the margin of the diapir or in adjacent country rocks. The mineraliza- tion is related to carbonate-rich epigenetic solutions which moved along major structural features closely associated with the intru sive diapir.

Jan 1, 1975