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Near Kangiara in south eastern New South Wales, Australia, a number of polymetallic (copper, lead and zinc, with minor silver and gold) mineral deposits occur within a relatively broad volcanic rock belt, intercalated with limestones, sandstones and shales, of Silurian age. The Kangiara deposit was the most significant for the region.Adjacent to the Kangiara deposit, the unaltered country rocks are more rhyolitic than elsewhere in the volcanic rock belt, and the mineralization is accompanied by silicification, chloritization, sericitization and argillization. The host rocks typically contain a higher K20:Na2O ratio than the volcanic rocks not associated with mineralization.In the Kangiara deposit the mineralization consist of massive (in part banded), fragmental, disseminated and vein-type copper-lead-zinc ores, with the massive and fragmental types divisible into pyrite-rich, chalcopyrite-rich and sphalerite-galena-rich varieties. With respect to this mineralogy, the ore textures and sulphur isotope compositions the deposit can be compared to the stratiform mineralization associated with Silurian acid volcanic rocks at Woodlawn, Captains Flat and elsewhere in the Lachlan Fold Belt, as well as the Tertiary Kuroko deposits of Japan.

Jan 1, 1990

By Kennedy B. J

The 1100 Orebody is the main copper production area of Isa Mine with an output of 390 000 tonnes per four week period and a work force of approximately 260 men per shift. Currently a total of 56 nippers work a three shift, five day week roster to-service crews spread over a strike length of 1000 m and a vertical height of 220 in. A variety of rail and diesel equipment provides shaftto cribroom and cribroomto sublevel work place transport of men and materials. Overall eficiency and safety has been improved with a selected group performing supply, storage, clean-up and "bus runs" throughout the orebody - activities which are further co-ordinated by an FM radio system linking units with a control clerk.

Jan 1, 1977

By G Huggins

Excavation in underground jointed rock masses creates cavities into which the surrounding rock mass deforms. Deformations, besides intact rock deformation, include mechanistic deformations such as slip and rotation. In this paper deformational moduli were measured for prototype and blocky (jointed) models using elastic analogue methods for stopes from MIM LimitedÆs Lead Mine. The blocks for the models were defined in terms of the prototypeÆs joint sets, their spatial separations, orientations and average friction characteristics. From dimensional analyses, a relationship between prototype and model deformations was used to predict stope mid-span deformations. The results of this physical modelling work, conducted in the 1970s, motivated an investigation into the electro-treatment of tailings backfill to achieve improved strength and stiffness characteristics. Tailings backfill containing fines and having a high clay content can be electrically dewatered, and at times grouted, cemented, ion exchanged or agglutinated, to achieve relatively high magnitudes of strength and stiffness. These treated tailings stiffnesses can reduce the deformation magnitudes within a rock mass and, in doing so, reduce problems encountered in mine pillar extraction. The application of these tailings modification techniques is examined in relation to the elastic analogue methods.

Jan 1, 1998

Geosynclines have been well studied for many years, but very little has been written about the concepts of sedimentary basins in spite of the vast amount of data available. They have been regarded, perhaps, as well- understood intuitively, and therefore not worthy of study. Many of the fundamental concepts of geology were developed during the 19th Century with the construction of coal mines, canals and railways. It was a happy chance that led railway engineers in the early days to think that trains could not climb any but the smallest gradient, so, in Britain at -least, numerous railway cuttings and tunnels were made. These exposed to view and study, in a better form than Nature usually provides, a great deal of interesting geology. Because of the lack of literature about the concepts of sedimentary basins, it is not possible to be sure what the early geologists thought. It seems that sedimentary basins were regarded as recording a history of subsidence during the early stages, when a transgressive sequence accumulated; and a history of uplift during the later stages, when a regressive sequence accumulated. It seemed axiomatic that the age of folding and faulting was younger than the rocks folded or Faulted.

Jan 1, 1987

By Walter GW

Rock mass classification systems for stable excavation design have been studied. The parameters which are important in such a classification system and those which should be included in a classification system formulated to predict explosive fragmentation behaviour are briefly reviewed and compared. There is significant overlap in the data requirements for excavation design and explosive blast de- sign. Recently there has been a trend to ob- tain some of the data required for excavation design by the use of both field and laboratory seismic investigations. The theory of seismic techniques is summarised and the results of seismic investigations carried out for excava- tion design are reviewed. On this basis it is considered that seismic techniques have the potential to be used for data collection prior to blast design. A programme designed to de- velop such techniques and which includes both field and laboratory experimentation is Presented.

Jan 1, 1978

By Y Hansen, J Petrie

Life Cycle Assessment (LCA) is increasingly being used as a decision-support tool within mining and minerals processing and metals production. However, a number of initiatives have highlighted the current limitations of LCA to accurately reflect the environmental performance of minerals and metals. These programs include:the Mining, Minerals and Sustainable development project (Stewart, 2001); the United Nations Environment Programmme/Society for Environmental Toxicology and Chemistry (UNEP/SETAC) workshop on LCA and metals (NRCan, 2002); the UNEP SETAC Life Cycle Initiative; and the review of the existing ISO 14 040 set of environmental management standards. Together, these initiatives highlighted concerns relating to the ability of LCA to engage with and support metals recycling, to adequately reflect the impacts associated with products from a multi-product orebody, the ability to adequately reflect the toxicity potential of metals in the natural environment and the fact that resource depletion focuses on mining (and not consumption) as the depleting activity in the life cycle of a metal. Additional impact categories to be included in LCA were also suggested. In this paper we demonstrate how existing initiatives are addressing LCA limitations. Finally we present the state of the art in Life Cycle Impact Assessment (LCIA) for two impact categories:resource depletion; and impacted land footprint for solid wastes.

Jan 1, 2004

An international raw material partnership, a $164 million 900,000 long ton per year aluxAna plant; an ideal location at Gladstone, Queensland, Australia - this is Queensland Alumina Limited, on stream in 1967 expanded 50 per cent by the end of 1968. Queensland Alumina Limited is the world¦s most modern alumina refining operation which is owned by an international consortium of four companies; Kaiser Aluminum & Chemical Corporation of the United States with 52 per cent; Alcan Aluminium of Canada with 20 per cent; Pechiney of France with 20 per cent; Conzinc Rio Tinto of Australia, 8 per cent. Q.A.L. operates as a co-operative -- the partners do not draw profits from the venture. Instead, each member of the consortium draws alumina in proportion to his share of the ownership. The method of disposal of this alumina is for the partner to decide.

Jan 1, 1969

By Manzoori AR

From a detailed combustion testing program and earlier experience with Leigh Creek coal, the Electricity Trust of South Australia (ETSA) gained a wide insight into the use of low rank coal fired boiler plant. This work is fundamental for the selection of boiler design parameters and other details which in turn determine the correct coal deposit selection for future power station development. In addition it gives boiler designers a good indication of the measures required to give reliable plant operation. Extrapolation from experience with existing plant, the designers main source of information, was not considered appropriate because of the lack of experience with similar coals. Brown coal beneficiation is also being assessed by ETSA in an attempt to improve the coal quality by the pretreatment of the raw coal prior to combustion in future coal.fired boilers. ETSA is also involved in the development of circulating fluid bed and gasification processes to determine whether these alternative processes are a more viable method of utilising the South Australian coals than pulverised fuel firing.

Jan 1, 1987

What is the best circuit to comminute primary crusher product to make beneficiation feed? Finding the best circuit to crush and grind minerals to beneficiation sizes is a complex problem that can lead to interminable discussion. Conclusions reached can be questioned. This will continue as long as the technology of comminution continues to expand, and is a mixture of many technical and economic factors in what is not a precise science. Laboratory and pilot plant procedures now exist that can help process engineers make sound decisions on which circuits are the best for crushing and grinding the specific ore being studied. It is the aim of this paper to discuss such procedures so a better under- standing of key decision parameters is avail- able, and to update comminution testing which has seen a. period of change in which new procedures have been introduced.

Jan 1, 1978

Trucks are the primary means of bulk material transport in Open Pit hard rock mines worldwide. They are considered to be the most- flexible system available. The large number of trucks used in some mines provides flexibility. Spare units allow for the reduced availability of the single units. Trucks have however very poor energy efficiency. Only 40% of the consumed energy is for transport of the payload, the remaining energy is required to move the dead load of the trucks. With the increase in cost, pressure, mine operators are now looking for alternative methods to make their operation more economical. Energy conservation and increasing haulage distances and uphill haulage are major factors in many well established operations. New methods have already proven themselves as more economical alternatives. Belt conveyors are an alternative means of transport with much higher energy efficiency. They use up to 80% of the consumed energy for transportation of the payload. Energy costs for conveyors are 30% of the energy costs for trucks on level transport and as little as 15% for elevating payloads. Belt conveyors require much fear spare parts and wear components than trucks. A factor of one to two times applies for level transport and ten to twenty times for uphill transport.

Jan 1, 1986

Wire rope, when used for hoisting on a mine is the weak- est and most vulnerable unit in the most expensive'-group of installations or! the mine. With the introduction' of hoisting on the S1Koepe"' sheave, a new technique was-established. This innovation brought with it the certain- advantages which long had been recognised and which are being developed further. For many years, drum winders of many types had been the sole means by which ore had been hauled from mines. This type of winder, with its capacity for rope storage on the drum, permitted mine operating personnel to cut short lengths from

Jan 1, 1964

The Bowen Basin of Queensland and the Hunter Valley of New South Wales are the two largest black coal producing areas in Australia. Mining activities require the availability of large on-lease storages for water and tailings. The legislative framework for the regulation of large dams is slightly different between the states. The paper provides a broad outline of the regulatory framework in each state, with particular reference to Queensland and New South Wales. In New South Wales, water storages and tailings dams are treated similarly by the regulator. Under the Queensland Water Act 2000, now proclaimed, referable dams are restricted to water supply dams the failure of which involves population at risk downstream. Tailings dams are excluded, being deemed hazardous waste dams regulated under the Environment Protection Act 1994. These storage facilities are required to include a ædesign storage allowanceÆ so that the possibility of spillway discharges is minimised. New South Wales is moving toward this requirement. A curious anomaly is emerging in Queensland: the legislative definition of hazardous waste û material resulting from the processing of minerals û does not extend to coal tailings since coal is not included in the definition of a mineral. The paper explores this and other ramifications for mining operations of the new legislation as well as general trends in criteria affecting the cost of providing water and tailings storages.

Jan 1, 2003

Uranium minerals were found in Australia as early as 1869, but it was not until the 1940's that a search specifically for uranium was begun. Instrument types and techniques used in early exploration are still used today, but have been developed into more sophisticated and portable types. Recent improvements in exploration have been the introduction of the gamma ray spectrometer, radon sampling and geochemical surveys. The environments of presently defined uranium deposits are predominantly sedimentary. Known deposits in igneous environments are usually small. The size of targets which are likely to provide economic deposits is of the order of 10,000 tons U308, producible at a cost of less than $10 per pound. Such targets are most likely to be in Precambrian sediments or in granitic masses. Recent exploration in Australia has included investigation of Precambrian sediments, Precambrian and Palaeozoic granites, Mesozoic and Tertiary sediments, Precambrian volcanic rocks and brecciated masses of unknown age. The origin and method of emplacement of uranium in these environments is not well known but there are indications that syngenetic sedimentary processes are important, and volcanic rocks may make a major contribution to the supply of uranium.

Jan 1, 1970

By G A. Davis, D G. Laughton

The great variability of mineral and energy prices has motivated some governments to incorporate a windfall profits tax into their mineral taxation regimes. Windfall profits taxes are a means for governments to capture additional mineral revenue when mineral prices are considered higher than some historic level. Governments need to be aware of the effects of such contingent taxes on the exploration, development and operating decisions of mining companies. Mining companies need to be able to calculate the full impact of windfall profits taxes on the economics of their projects. This paper examines the valuation of a multi-phase copper-gold project in the presence of a windfall profits tax. Real options Monte Carlo simulation is used to characterise the different exposures of the mine owner and of the government to the risky cash flow streams that they receive from the project. The results highlight that Monte Carlo simulation paired with the real option valuation method is able to account appropriately for the differing risk exposures, while the traditional discounted cash flow valuation model is not. Our key conclusion for governments and mining companies is that the impact of contingent tax and royalty terms can and should be assessed using advanced valuation techniques, and the results used to improve contract designs under the constraint of actual and perceived fiscal system stability.

Jan 1, 2007

Despite mineral sand occurrences having been noted since the 1970s, the Wemen North Mine is the first operation to commence commercial mining within the inland Murray Basin. The deposit was discovered in the 1990s and, following lengthy resource development, mining commenced in 2001. This initial mine was established as a pilot operation to test the commercial viability of mining in the Murray Basin, with subsequent expansions planned if the mine proves successful. The deposit lies beneath arable farmland close to the Murray River and is hosted by Pliocene marine sands, with a geometry resembling a classical beach strand placer. The operation utilises traditional dry mining overburden removal techniques, with ore mining carried out using a floating dredge and concentrator. This paper looks at the geology of the Wemen North deposit, the mining techniques and challenges as well as grade control practices employed to mine this palaeo-beach placer deposit.

Jan 1, 2003

The prime requirement is market, which for NZ inevitably means overseas markets. In order to be internationally competitive, the economies of scale and mechanical handling are essential. Since significant markets have not been sought, the full extent of our industrial mineral potential is not known. In general the technology exists to impart the desired quality, but at a price. Price is the main constraint, which may confine truly competitive operations to coastal situations to avoid high internal freight charges. Some commercial deposits of construction materials are being sterilised by zoning, making the costs to the consumer and country unnecessarily high. Unless management is enlightened and marketing is forceful, it can restrict growth. There is a good case to mount a search for phosphate minerals. The main growth areas are likely to be direct shipping ores like limestone, silica sand, and olivine, but in particular pumice.

Jan 1, 1978

The Tregoora Gold Project is centred around the old Mitchell River Antimony Field located 100 kilometres west-northwest of Cairns, North Queensland. The project is currently the subject of a joint venture between Strategic Minerals Corporation N.L. and Hawk Investments Limited.Historical BackgroundThe Tregoora area was first prospected for antimony and gold around 1890. During the periods 1905 to 1914 and 1937 and 1944 approximately 100 tonnes of antimony and an unknown quantity of gold were won from a number of small mines the principal one being the "Retina". A strong increase in the demand for antimony in the early 1970's resulted in renewed exploration activity in the region and the re-development of the Retina Mine. Despite the intermittent interest in the region for antimony it was not until 1984 that the potential of the area for hosting gold resources was realised with the delineation by Strategic Minerals Corporation N.L. of a significant gold deposit now referred to as the Black Knight.

Jan 1, 1986

The writers of these notes, having conducted some tests on the steam consumption of air compressors under varying conditions, believe that the detailed results of such tests will be of interest to the members of the Institute, and may lead to the contribution of further and more valuable information, of benefit both to manufacturers and users of this class of machinery-to the manufacturer in that he frequently has the opportunity of giving a very thorough test to the machine in the shop, and-tothe user or purchaser by making clear to him what may be reasonably demanded of a high-class machine. It must be remembered that, though of the highest importance, a low steam consumption is but one of the many features of a high-classmachine; for the present, however, it has been considered advisable to confine the paper chiefly to the first-mentioned aspect, with such information concerning the air ends as is obtained along with the steam consumption tests. Unfortunately, too few of these tests are conducted, and but few results are published, therefore the writers feel that no apology is needed in bringing their results before the members.Some nine months ago the Brilliant Extended G. M. Co. was supplied with a compressor by Messrs. Thompson and Co., of Castlemaine, and with the object of testing its actual performance.

Jan 1, 1907

The products required by customers today have become far more complex and consequently more demanding to handle. And thereÆs the dilemma. Nowadays, people tend to stick to a trade for just a few years instead of for a lifetime, and this means that the customerÆs employees cannot be expected to get more than general knowledge of how to handle modern mining and construction equipment. To meet this challenge, major steps are being taken by suppliers to make their æmusclesÆ more user-friendly. Also the supplier is assuming a larger share of responsibility for the product including operators training, supply maintenance services and, in many cases, performance guarantees. In other words, the supplier is today supplying a function or an activity rather than just muscles. Some of the new generation drill rigs have been on the market for a few years and reliable experience has been collected and is addressed in this paper. Some of the information is well supported by figures while others are just statements from users of the rigs.

Jan 1, 2005

The Tavua Power Proprietary Ltd. was created in 1936 for the purpose of supplying electric power, compressed air and water to the mining field.The original share capital was subscribed on a two-third:one-third basis by the Emperor Gold Mining Company Ltd. and Loloma (Fiji) Gold Mines, N.L. In 1940, Fiji Mines Development Ltd. (later changed to Dolphin Mines Ltd.) was admitted as a shareholder, and, in 1950, a further change occurred. The present shareholding in the Company is as follows:A central power station was decided upon to reticulate power and compressed air over the whole field and building commenced in May 1936.The original plant comprised three Belliss and Morcom diesel generating sets 770 b.h.p. 525 kW 3,300 V, 3 phase, 50 cycle; one Belliss and Morcom diesel compressor set 2,09'0 cu. ft. of free air per min. at 90 lb. gauge 300 r.p.m., and two small Ruston-Holman diesel compressor sets each of 525 cu. ft. capacity taken over from Loloma (Fiji) Gold Mines, N.L., and the then existing Koroere Gold Mining Company.BuildingThe original building was 130 ft. long by 47 ft. wide with an elevated switchgear annex on the west side from which a clear view of the engine room is available.

Jan 1, 1953