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An empirical method of estimating dense rock (D.R.E.) equivalent volumes erupted as airfall tephra, described in a companion paper in this volume, is elaborated, and its accuracy discussed. Estimates obtained from a single eruption can be classified as to whether they show positive, negative, or constant relative dispersion. For positively dispersed tephras (estimated volumes increasing with distance), this procedure improves the accuracy of the method. The technique is applied to selected andesitic tephras erupted from Egmont Volcano, New Zealand, during the last 28 000 years, which are found to range in volume from about 1.5 x 107 m3 up to about 2.4 x 108 m3 D.R.E. With a factor of about 16 between the smallest and largest volumes, this contrasts sharply with the rhyolite volcanoes in New Zealand, where the difference factor is usually of the order of 100. The largest tephra eruptions at Egmont are small compared to the largest debris avalanches, which have exceeded 1010 m3 (10 km3) in volume.The magnitude versus frequency relationship, calculated using a maximum likelihood method, establishes the limits of eruption magnitude at Mt Egmont as 107 to 109 m3 D.R.E. For some volcanoes, the magnitude-frequency relationship changes with time, owing to clustering of eruptions, separated by long dormant intervals. Ngauruhoe Volcano, New Zealand, is an example. Within eruptive episodes, the mean interval between eruptions of >_ 105 m3 is about 0.9 ¦ 0.65 years. The mean interval between eruptive episodes in which >_ 106 m3 is erupted, including episodes in which this volume is erupted gradually, is about 25.8 ¦ 6.6 years, and the mean dormant interval between all episodes is about 5.2 ¦ 3.0 years. At present Ngauruhoe is in an unusually prolonged dormant period, 50% longer than any in the historical record, since 1839.

Jan 1, 1990

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

In Australia we usually define "resource" in purely material terms, and rarely relate it to intellect and human capacity. We look at the sheer abundance of our natural resources and are satisfied with the feeling that we don't really need-to rely on using our brains. Certainly our country is fortunate to have the mineral resources it does, but in many ways Australia's worst enemy is its "lucky country" syndrome because we tend to underutilise the great resource we have in the capacities of our people. Raw material exports will undoubtedly continue to contribute a major share of our export revenue, but to harness the riches our country has to offer most effectively we need the vision and planning necessary to bring together our material and human resources. There is a need not only to find, exploit and process our minerals economically, but to turn as much of our mineral wealth as possible into high value products before it leaves the country. In particular we must use our brainpower if we want to maximise economic benefit from and political influence over the strategic minerals which leave our shores. In the past we have been successful in finding and exploiting minerals because our mining industry has been in the forefront of private sector research and development. But if Australia is to have an advantage over other mineral rich countries in insulating itself from the effects of cyclical swings in commodity prices, then the future of the industry must lie even more in technological sophistication rather than depending. on such considerations as size and location of mineral deposits. To survive, our mineral industry must have the foresight and resourcefulness to make its own luck. There are two keys to increased efficiency in exploration and production and in further processing methods: enhancement of the skills of the workforce and continual improvement of R&D.

Jan 1, 1986

By Corbett GJ

The Bulolo Graben represents an intra-arc rift formed by activa- tion of transfer structures in an extensional setting formed be- tween the eastern and western sectors of the New Guinea Origin. Crustal thinning has facilitated the emplacement of dacitic Edie porphyry intrusions, locally as flow dome complexes, phreatomagmatic (diatreme) breccias and the Bulolo ignimbrite/ agglomerate as an extrusive equivalent of the Edie Porphyry. Gold mineralization is localized along intra-graben structures, com- monly at the intersection with cross structures and occurs in sub- sidiary dilational fractures and not the localizing major structures. Gradations are apparent in the styles of mineralization according to the degree of erosion of the hydrothermal system. Hamata occurs as the deepest mineralization of the quartz-sul- phide style Wau, Hidden Valley, and Edie Creek are dominated by carbonate-base metal styles. Kerimenge grades from quartz sulphide through carbonate-base metal to epithermal mineraliza- tion, the latter style also being present in the periphery of Edie Creek. Here, pre-existing fractures of the Edie Creek Structural Corridor have been reactivated by movement on NS structures to form the ore-hosting dilatant lodes. Fluid flow may have been from the vicinity of the Nauti diatreme margin and along the vein System.

Jan 1, 1997

Lihir Gold Mine is situated in a dormant volcanic caldera on a small island off PNG. Not æextinctÆ but dormant. Current ground temperatures are up to 150 degrees Celsius with active geysers in the workings of the mine, pools of boiling ground water adjacent to low-grade dumps and hydrogen sulphide gas emissions. It is a unique mining environment by world standards. This paper will deal with the following issues encountered and managed by the operation:blasting in hot and reactive ground; management of sulphide gas emissions; disposal at sea of all mining waste rock; one dear to all Australian minerÆs hearts û dealing with landowner groups; and unusual human resource issues.

Jan 1, 1999

Dimension stone is the term generally given to rock used in building construction. During early European history in Otago, locally available dimension stone products were easily obtained. Crude rock shelters built on river banks with schist rock within Central Otago soon gave way to more established and sophisticated permanent homesteads constructed with the same materials. Victorian architectural achievement is celebrated in Otago with many fine bluestone block buildings. When the University Council decided to build substantially in stone, it narrowly escaped disaster. It was well known at the time that brick in Dunedin was of an inferior quality and that it soon wasted. Rev Dr Stuart said before the 1879 Commission that æthe Council had some old-world notions and liked to have the University with some architectural styleÆ. Contemporary utilisation of dimension stone is generally restricted by expense to a simple veneer. Stone products produced from Otago quarries have found ready markets in other areas in New Zealand , particularly prior to the share market crash in 1987.

Jan 1, 1992

By R van Berkel, J Lay, D van Beers

The development of regional resource synergies in intensive areas with concentrations of minerals processing industries provides a significant avenue towards sustainable resource processing. Gladstone (Queensland) and Kwinana (Western Australia) are two of AustraliaÆs major heavy industrial areas. There are a number of successful regional synergies in both areas. In addition to the existing regional synergies in both areas, more potential synergy opportunities appear to exist which, upon implementation, could benefit industry, the environment and the community. To further enhance the development of such potential regional synergies, the Centre for Sustainable Resource Processing (http://www.csrp.com.au) commissioned research projects to facilitate the identification of potential synergies and assist with their implementation in both regions. This paper presents a selection of specific examples from both regions to illustrate the sustainability benefits from regional synergy developments. Although the composition of industries in the Gladstone and Kwinana regions is different both in terms of geography and industry diversity, similarities in synergy developments for both regions are apparent. Consequently, the examples discussed in this paper are organised around the key themes of water, energy and inorganic by-products. Comparison on a theme basis highlights success factors of successful synergies and demonstrates the range of benefits resulting from their implementation.

Jan 1, 2006

A synthetic gold-silver telluride material (mainly sylvanite) has been prepared and its physical and chemical properties checked. Flotation tests using a Hallimond tube were conducted using commercial xanthate collectors. At collector concentrations of 10-3M with the addition of 5 × 10-4 M CUS04, no obvious differences in the mineral recoveries were seen irrespective of whether amyl, secbutyl, isobutyl or isopropyl xanthates were used. However, when the concentration of xanthate was reduced to 10-4 M or in the absence of the copper sulphate activator, the effectiveness of the collectors was in the order: amyl > secbutyl > isobutyl > isopropyl > ethyl. Changes in the slurry pH appeared to have little effect on the recovery of the telluride mineral.Leaching tests of the precious metal telluride showed that both gold and silver dissolve in alkaline oxygenated cyanide solutions but at a much lower dissolution rate than metallic gold or silver. Both leaching tests and electrochemical measurements indicate that the dissolution rate of gold-silver telluride is controlled by the pH and cyanide concentration of the leachant.Roasting the gold-silver telluride materials in air at temperatures between 550 and 750°C resulted in its decomposition into a metallic gold-silver alloy and tellurium dioxide.

Jan 1, 1994

By Evans RH, Todd G

Statistical thinking and statistical process ppq;ro4 are essential adjuncts of total quality management aqd too continuous improvement of operating efficiency arid, p*Nc; a4 W,

Jan 1, 1991

By Readett D. J

Soluble salts can be removed from Bowmans lignite by water and acid leaching. The success of the removal of water soluble or acid exchangeable impurities is directly associated with the efficiency of dewatering these slurries. The filtration characteristics of a slurry at its natural pH (4.0) were poor, with a filter cake moisture of 65%. Acid treatment of the slurry at pH2 caused the filter cake moisture content to drop to 61 %. Various oils, oily surfactants and a flocculant were tested to determine the conditions for minimum filter cake moisture. A series of pilot scale filtration tests were conducted on flocculant dosed slurries with and without washing on a horizontal test unit. Moisture contents of 54% were obtained in laboratory testing using high additions of oily surfactant. For the pilot scale test work, moisture levels close to 60% were obtained with low flocculant additions, similar to results obtained in laboratory studies. Removal of soluble salts could be correlated directly to the final moisture content of the filter cake. This process of leaching followed by filtration resulted in the removal of approximately 75% (more than 80% with washing on the cloth) of the sodium chloride originally present in the lignite.

Jan 1, 1989

By G A Brown

Environmental legislation is changing rapidly throughout Australia at the present time, and with that change comes additional responsibilities for the mining and petroleum industries. Among the many changes that are being made are increased penalties for both criminal and accidental environmental impairment. The defences for criminal offences are limited and for other offences the laws may impose strict liability - in effect the offender is guilty until proven innocent. Mines may be included under contaminated land legislation, creating additional liabilities for clean-up, rehabilitation and long-term management. It is not unknown in Australia for the value of a mortgaged property to be less than the amount of the environmental liability acquired by a mortgagor in possession due to contamination of the site. An essential part of the management program for resource projects is now the regular conduct of an environmental audit, the results of which assist in the management of the legal and financial liabilities facing company directors and managers. The audit can also assist with negotiations with government agencies, staff, unions, insurers, Aboriginal and other community groups. An environmental audit may also help to ensure that companies are claiming the maximum allowable deductions for environmental works under the tax laws, and provide evidence in support of such claims. Environmental legislation affecting resource industries Environmental legislation in Australia is changing rapidly and can impose massive constraints, substantial administrative costs, and considerable liability on directors, managers and the corporation. Pollution control legislation Every State and Territory of Australia has a range of pollution control legislation contained in either individual acts relating to air, water, noise and land, or embodied in a single environment protection act. Pollution control legislation provides a critical management baseline for resource industries throughout Australia, often requiring the full-time attention of an environmental manager or an environmental department. In general, it is an offence to discharge effluents into water, or emit gases into the atmosphere above prescribed limits, cause noise above a regulated level, or contaminate land without a licence. A licence determines how much of a substance can be discharged, the location, the receiving environment, the quality, and the time at which discharges can be made or noise can be caused. Planning legislation Planning legislation controls where a project is located, how it will be constructed and operated, how large it is allowed to be, and what will happen once the project is completed. Development consents or approvals will generally contain a range of conditions controlling the preparation of the site, the construction of the facility and the way it is operated throughout its expected life time. Resource projects may be regarded under legislation as scheduled or designated developments requiring special treatment during the decision-making process. Under planning legislation, it is usual for resource projects to be subject to an environmental impact assessment process. Resource legislation Resource legislation specifically covering mining and petroleum in Australia, also contains requirements regarding protection of the environment during exploration for and extraction of minerals and oil. A mining or petroleum production lease usually contains numerous conditions regarding protection of the environment and rehabilitation of the site during and after the life of the extractive process.

Jan 1, 1994

The research, development and testing of a Blast Control Plug (U.S. Pat. #4,754,705) funded by the U.S. Department of Energy is described. The plug's function is to improve blasting efficiency through the enhancement of stemming effectiveness and thereby reduce drilling and blasting costs. The plug comprises a solid unit placed in the blast hole within the stemming column above the explosive. It is designed for use with back filled drill cuttings or any other suitable material The research and development program comprised the testing of the plug in small diameter holes in competent rock for both bench and crater blasting configurations and full scale field trials in multiple hole and row blasts using blast holes of from 76 to 387 mm in diameter. Test measurements included stemming displacement and velocity, face movement and extent, peak air over pressure and ground surface peak particle velocity. Data acquisition equipment included a Spin Physics SP2000 high speed video motion analysis system, and acoustic and seismic monitoring units. Substantial reductions in stemming ejection velocity or ejection elimination were achieved whilst reducing stemming length by up to 35% over conventional practice. Peak air blast pressures were also reduced by between 8 and 25 dB. A strong inverse relationship between rock face movement and stemming ejection velocity was found. The implications of the importance of stemming effectiveness in blasting and computer blast simulation is also addressed.

Jan 1, 1990

By Hall J. S, Zuiderwyk M, Reid A. F

A prototype version of a computer controll- ed on-line scanning electron microscope image analyser, employing the real-time signals ob tamed by digital control of the electron beam has been used to obtain statistical quantificat lion of a wide range of mineral grain character istics, including composition, size distribut- ion, and degree of liberation. These propert lies have been determined for suites of whole particles of flotation concentrates, mounted without further preparation. The facility is also well adapted to the measurement of general Istereological parameters. The computer control software is based on an operating system which includes the device drivers and which is linked to FORTRAN programs [containing the procedural algorithms. The beam scanner provides a 4000 x 4000 point raster swept at a 10 Mhz rate in steps of 1 to 200 points and a set of up to 8 signal channels which respond to electron or energy dispersive X-ray signals to provide a digital attern.characterizing the sample composition. the beam is stepped at high speed until a part- 'cle or phase boundary is encountered; a longer well time is set if X-ray data is required. he digital scanner interrupts the computer

Jan 1, 1977

By Hughes DC

Coal development in New South Wales can involve a complex series of government approvals, a requirement that results from the coincidence of many development sites with environmentally sensitive areas. The concept of network analysis is applied to the pre- development regulatory procedures leading up to the grant of a coal lease. The network facilitates a quantitative and qualitative analysis of activity schedules relating to pre- requisite statutory approvals. The sequencing of activities (with clear start and finish nodes, identification of sensitivities and time estimates for completion of each phase of the network) provides government and industry with an effective planning tool.

Jan 1, 1983

By Glastras M. V

The presence of arsenic in solutions which result from the processing of many sulphide minerals leads to a need to understand its speciation in aqueous systems and the reactions of those various species. This paper deals in particular with the precipitation of arsenic from aqueous solution in the form of insoluble inorganic compounds in order to remove arsenic from various hydrometallurgical process streams. The solubility and stability of the precipitates is examined. It has been found that many of the arsenic compounds presently used are more soluble than previously accepted and unstable in disposal sites such as tailings ponds.

Jan 1, 1987

By A Mulyadi, J Barber, R Golden

The Deep Ore Zone (DOZ) underground mine will be a 25 000 tpd mechanised block cave operation starting production in 2000. The ore handling system consists of a direct truck dumping 54 +74 gyratory crusher, which feeds into an ore bin. An apron feeder below the bin is used to load a conveyor belt. This paper describes the design, sequencing and methodology of the crusher station, ore bin and feeder chamber excavations. The Geotechnical investigation and analysis of the site are also discussed as well as the design, installation and quality control of the long-term ground support methods.

Jan 1, 2000

By Nilmani M, Malone J, Taylor RN, Floyd JM, Gray NB, Fountain CR

CSIRO staff and University of Melbourne staff and students collaborated in an intense programme of investigation on the CSIRO 50 kg Sirosmelt pilot plant.In two days of operation copper matte converting and zinc slag fuming trials were performed, whilst investigation of the process dynamics and process chemistry was carried out. This exercise is an example of the techniques available for process evaluation, which can rapidly advance the understanding of pyrometallurgical operations by use of a team approach covering a wide range of experiments.

Jan 1, 1985

By Armstrong A

Queensland is Australia's second largest mining state with world-class deposits of coal, base metals, bauxite and magnesite. The total value of Queensland's mining production is about $5 billion per annum, and coal accounts for around 55 per cent of that total. The environmental issues which arise as part of management and regulation of the industry are resolved within the EMOS process. The Environmental Management Overview Strategy is the cornerstone of the policy 'Environmental Management for Mining in Queensland' developed jointly by the Queensland Department of Minerals and Energy and the mining industry. The Gordonstone Coal Mine is the largest underground mine to gain approval under the new policy. Accordingly, Gordonstone has a well planned environmental management program which takes into account site-specific factors and provides for continuous compliance with the provisions of the Mineral Resources Act in a self-regulatory context.

Jan 1, 1994

By Ramsay WRH, Morand V

Structural, mineralogical, and textural data from the Tarnagulla Goldfield demonstrate that the area has undergone three significant phases of deformation. The first phase of deformation (Dl) predates the intrusion of the Tarnagulla pluton, which has been dated using K/Ar as 391 ¦ 5MY. We regard this pre-granite deformational event as the major regional deformation. Gold-bearing quartz veins have been deposited in dilational sites on west-dipping reverse faults. These sites demonstrate a geometry related both to faulting associated with Dl and the plunge of the Fl fold axes. This evidence, together with chronology of unmineralised ? D2 and D3 faults, the absence of quartz veining associated with D3 events, and the deformation of carbonate-quartz-biotite-sulphide aggregates within Sl by later S2, lead us to conclude that the bulk of the mineralisation was essentially syn- or late Dl. S'80 values for fluids in equilibrium with vein quartz from Central Victoria have indicated equivocal support for either a magmatic or metamorphic origin. Our evidence supports a pre-magmatic origin for mineralisation at Tarnagulla and hence tends to favour a metamorphic fluid source.

Jan 1, 1995

The history and milestones in the evolution of support systems utilised in the mass-mined chrysotile mines of Shabanie and King are discussed in detail. The use of block caving, false footwall or sublevel caving mining methods brings with it some major support problems, which are exacerbated, in our low rock strength mining environments. The paper discusses the various support elements and systems that have been used successfully or otherwise in these operations. Some predictions for the future of rock reinforcing in our ground conditions are highlighted, in relation to geomechanics, levels of mechanisation and production risk analysis.

Jan 1, 2000