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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 Goode RA

It is-assumed that a pipeline system is economically justified as a means of transportation.. The terms "True Life" and "Economic Design Life" are defined. The most usual design alternatives to be considered from both physical and economic -viewpoints are listed and a summary is given of the main factors to be costed in assessing the relative economics of each alternative. A brief statement of the recor mended method af economic. assessment is given and an example is included. The paper aims to present a reasonably accurate, simple and practical method of considering the main economic factors which govern design.

Jan 1, 1962

Warrego copper ore characteristically contains 0.05-0.2% bismuth, which on upgrading produces a concentrate of approximately 1.3% bismuth. Early smelting of this concentrate (1973) was accomplished in a flash furnace (eliminating 92% of the bismuth in the con- centrate) and Top Blown Rotary Convertors (eliminating 85% of the bismuth in the matte). However 1.3% bismuth was considered the max- imLun bismuth level that could be treated. Geological evidence indicated that the bismuth level in~the copper ore would increase and that the bismuth level in the Warrego ore would be 0.3-0.7% bismuth. Treating these ores would produce a copper concentrate with bismuth levels far in excess of those accept- able to the smelter and still produce low bismuth content blister (limit 0.03% bismuth).

Jan 1, 1984

By Gao H

Based on the author's research and plant practice experience of the last decade, several technological approaches have been developed to increase the recovery of gold and silver associated with sulphides. This paper gives a general discussion of some technological problems encountered in this area in five aspects and introduces the different approaches employed in three typical mineral processing plants to increase recovery of associated gold and silver. On the basis of studying occurrence characteristics of gold and silver minerals in sulphide ores and of determining loss locations of gold and silver on flotation process, a remarkable improvement on the recovery of gold and silver in all these three plants was made by choosing proper grinding fineness, using combined collectors of good selectivity, properly decreasing the grade of main metal concentrates, making reasonable arrangement of the products of main metals, or a combination thereof.

Jan 1, 1993

By Tonkin D. A

Poor performance in the several stages of the magnetite recovery circuit, coupled with poor desliming through inefficient and over- loaded desliming screens, led to excessive magnetite consumption. An accurate and reliable sampling programme was established covering all outlets of the plant. Emphasis was placed on frequency of increments in an endeavour to detect extreme conditions of short duration. Systematic checking of the entry points to these outlets than identified those sections of the recovery circuit at fault, namely magnetite recovery separators and the heavy media cyclone product rinsing screens. More product rinsing water was provided, and modifications to the rinsing screens improved the efficiency of these units. Consistency of operation through automatic control of level eliminated the sudden massive losses in the magnetic separators. Load on the recovery circuit was then reduced by improvements to the raw coal desliming screens. A 50 per cent reduction in magnetite consumption was achieved.

Jan 1, 1974

By Sudharto RT

Sulphides of Cu, Pb, and Zn occur in quartz veins associated with a quartz monzodiorite stock at Gunung Limbung, West Java. The mineralization was polyphase and occurred at depths of less than lkm. Wall- rock alteration is extensive and typically consists of an outer zone of propylitization and an inner zone of potassic (K-feldspar- rich) alteration. Sporadic argillic altera- tion is probably of supergene origin. A variety of elements were mobilised during hydrothermal alteration and Ba in particular shows mared enrichments in the potassic zone. Fluid inclusions in the vein quartz indicate that temperatures of mineralization were within the range 250-3900C and that two fluids with differing chemistry were involved. One fluid had high Ca/Na ratios and a low overall salinity, the other had low Ca/Na ratios and a moderate salinity. The former is probably of meteoric derivation, whilst the latter had a magmatic origin. Precipitation of the sulphides was probably brought about by mixing of these fluids.

Jan 1, 1987

A number of small copper deposits occur in the Pernatty Lagoon-Mt. Gunson area. Textural and mineralogical differences distinguished the lagoon sulphide deposits, which occur in a water filled basin of permeable bedrock immediately under the lagoon floor, from the largely oxidized deposits which occur in the low hills adjacent to the lagoon deposits.Groundwaters are carrying copper, and to a lesser extent zinc, downstream to the lagoon. Several species of sulphate-reducing bacteria are widespread in the groundwaters and lagoon muds.It is suggested that copper sulphides were first deposited at the same time as, or soon after, the host Proterozoic sediments, and that during the present cycle of erosion the lagoon deposits may have been enriched, or largely formed, by bacterial precipitation of copper sulphides from laterally migrating cupriferous groundwaters.

Jan 1, 1971

By S A. Johnson, J Cassidy, J L. Mauk

Geophysical anomalies at Puhipuhi reflect both diverse lithologies and different degrees of hydrothermal alteration. Most significant is a strong negative gravity anomaly (up to 50 g.u.), encompassing but extending beyond areas of known alteration, which is modelled as a deep zone (up to 3 km) of reduced density in the host greywacke basement. This zone, interpreted as being due to alteration (at least in part), closely correlates with the extent of overlying basalt flows. The gravity data indicate that the most intense alteration occurs below the basalts and correlates with the location of previously inferred hydrothermal upflow zones. These observations suggest that the basalt may have acted as a cap rock to a mineralising geothermal system. Aeromagnetic data identify highly variable but typically low magnetisations in the basalts which suggests that alteration may have been contemporaneous with volcanism. These geophysical data at Puhipuhi confirm the locations of centres of known alteration and suggest potential exploration targets below the basalt cap where there is no surface manifestation of alteration. Further implications of these results are discussed in Locke et al. (1999).

Jan 1, 1999

As mines become deeper, the problems of heat in the workplacebecome more acute. An important response from the industry hasbeen the widespread adoption of microclimate cooling such asair-conditioned cabins. However, not all work in mines can becompleted from inside an air-conditioned cabin, and in any event,it is still important to keep the ambient air in the mine outside ofany microclimate to a safe temperature. An important method forbringing workplace temperatures under control is the appropriateuse of refrigeration. The application of refrigeration inmechanised mines has been recently described (Brake, 2001;Brake and Fulker, 2000). This paper provides an overview ofsome of the important engineering considerations in thespecification and selection of mine refrigeration plants. Thepurpose is to provide a basic understanding of refrigerationprinciples, practices, terminology, hazards and opportunities formining engineers or other personnel who may need to beinvolved in the introduction of refrigeration onto a mine site.

Jan 1, 2001

Most mining projects will involve some level of financial markets price risk. This is because commodities are generally traded in $US. The project will also incur costs in $A and if based in Australia will seek to generate a return in Australian dollars. Therefore the project faces commodity, foreign exchange and interest rates risk. As a business you may wish to maintain these risks within your business. However if the project requires financing to be provided then the financiers will want to ensure that there is a level of certainty attached to the cash flows to support the debt repayments. This is achieved by hedging the financial market risks. Traditionally the hedging process has been based on underlying assumptions within project models, which incorporate views on the direction of the underlying price risk. These views can be formed in an ad hoc manner. Gathering information from a variety of sources including economic forecasting and modelling, technical analysis, seeking market expert views. However, given the historical accuracy of such forecasts locking into long-term fixed hedging arrangements can create an inflexible environment that can restrict the opportunity to benefit from the underlying volatility of financial markets.

Jan 1, 2003

Mine site restoration, involving the re-establishment of original ecosystems, is a far greater challenge than revegetation, which simply aims to stabilise the site and to give it a green appearance. One of the challenges is to establish a simple yet effective measure of restoration success. A potentially useful approach is to focus on particular groups of plants or animals which are likely to provide a general indication of the state of the ecosystem in which they occur. Ants have been used extensively by the mining industry in this context, particularly in northern Australia. Ants are likely to be useful bioindicators because of their general importance in the Australian environment, and because of the many linkages they have with other parts of the ecosystem. Moreover, ant community structure responds to stress and disturbance in predictable ways, and therefore provides an interpretable measure of ecosystem change. This is illustrated by a study of ant recolonisation at Ranger uranium mine. However, the extent to which ants reflect the responses of other ecosystem components is poorly documented. This is currently the subject of a collaborative project between OSS and CSIRO.

Jan 1, 1994

The Mons Cupri Cu-Pb-Zn deposit is situated within a complex Archaean volcanic sequence dominated by rhyolitic fragmental rocks. This sequence is underlain by a 150 m group of rhyolitic ash flow tuffs with minor conglomerate and sandstone, and is overlain by approximately 180 m of dacite and andesite flows. The Mons Cupri sequence itself consists of several elongate or circular rhyolite domes, flanked by rhyolitic fragmental rocks ranging up to 400 m in thickness away from the domes. The lithology of clasts (typically 1 cm to 1.5 m in size) provides strong evidence that the flanking fragmental unit was derived by explosive eruptions associated with the rhyolite domes. An approximately 15 m thick shale horizon, bleached and silicified at its base, overlies both the rhyolite domes and the frag- mental unit. A south-dipping chloritic pipe-like body, with near-surface dimensions of 1,000 by 250 m and narrowing at depth to produce a cone-shaped cross section, lies within the rhyolitic frag- mental rocks about 250 m north of the largest rhyolite'dome in the Mons Cupri vicinity. Its east west elongation parallels that of the rhyolite dome. Ghost fragments indicate that the material in this fissure is a severely chloritized derivative of the rhyolitic frag- mental unit. The chloritic pipe is overlain

Jan 1, 1973

In the Renison Bell area of western Tas mania, a series of Lower Cambrian quartzites, shales, carbonate beds ("dolomites"), cong- lomerates, tuffs and argillites have been folded into a broad monocline whose general strike is NW-SE, plunging slightly north and dipping NE. The downwarped eastern side of the monocline is disrupted by a steep (50-800) east dipping normal fault, known as the Bassett Structure, whose throw is in excess of 500 m. A series of flat north dipping normal faults, each with a throw of approximately 50 m, further disrupts the sequence. All major faulting was pre-mineralization. A cassiterite- bearing Devonian quartz porphyry body intrudes this Cambrian sequence 2 km south of the currently operating mine. Of economic importance is the presence of three carbonate beds in the sequence. These carbonates consist of a mixture of calcite, dolomite and siderite. The No. 1 (youngest) and No. 2 carbonate beds are each approximately 15 m thick and are separated by 20 m of hematitic conglomerates and tuffs. The No. 3 (oldest) carbonate bed is approximately 5 m thick and is separated from the No. 2 horizon by 50 m of dark grey, finely laminated shales and quart- zites. Whilst the carbonates are remarkably persistent over at least 30 km2, facies changes are common and as a result of these changes, the carbonates vary considerably in

Jan 1, 1973

By S M. C Verryn

The amount of raw material used in the production of cement can be reduced by partially supplementing it by pozzolanic waste material without changing its properties negatively. This paper discusses results of an investigation using slag from the Pt industry, from the production of steel using Midrex processes as well as fly ashes from different coal power plants in South Africa. These are blended in a 20 per cent slag or fly ash to 80 per cent cement ratio. The properties of the mixtures depend on the phase composition, chemistry, grain size and the sources of the materials. The results are promising, but show variable behaviour depending on slag and cement composition. Compressive strength tests as well have heat flow curves showing the hydration behaviour, indicating that 20 per cent addition of slag or fly ash to ordinary Portland cement is viable. There is a large potential to use slag in cement mixtures and this study can be used to develop cements that will positively influence CO2 emissions and help to reduce large slag and fly ash stockpiles.

Jan 1, 2008

By R Nakia, R Livingstone

Historically the Goldfields of Victoria produced large volumes of gold. Interest in these historical Goldfields has grown over recent years with a view to restarting production of gold. A notable example of this is the Bendigo Goldfield. There is also interest in the Ballarat Goldfield and Ballarat Goldfields Ballarat East Project is a particular example of this. The aim of this paper is to describe the ventilation aspects of the potential Ballarat East project. The mine is proposed as a decline access. The paper gives an overview of the project and in particular the ventilation planning associated with a number of possible equipment scenarios. The paper also analyses the main ventilation pollutants that are likely within the proposed mine as it develops to increasing depth. An attempt is also made to determine the depth at which mine climate will become the dominant pollutant rather than diesel exhaust pollutants.

Jan 1, 2003

The ""comparable sales"" method of valuation attributes value to an asset by reference to actual sales of comparable assets or to the market capitalisation of companies with comparable assets. This methodology is widely used in real estate valuations. The real estate approach can be used to value mining and exploration properties where there are actual sales of comparable or similar assets in the recent past. The practical limitations of the comparable sales method are well known and self evident: limited number of transactions, limitations on comparability and inadequate data. The real value of the comparable sales method is in its use as a validity check. Estimates of value of mining and exploration assets are so sensitive to so many variables that all valuation methods have limitations. Accordingly there is real value in attempting to establish benchmarks from comparable sales. Apparently sophisticated valuation methods can mislead by creating the impression that valuation is a precise science. The judgement of the valuer is critical and judgements can be wrong. Any available evidence from actual sales that are even remotely comparable can provide useful input to the valuation process.

Jan 1, 1994

The Australian industrial relations system is in a state of constant change. We are undergoing a transformation from a compulsory arbitration and an award based system to one which is fundamentally rooted in the concepts of enterprise bargaining. This is true both at the State and Federal level. The structural changes which facilitate the movement away from the predominance of Awards to enterprise agreements has been fostered by both sides of the political spectrum and is a cornerstone of their respective industrial relations platforms.In determining what form or combination of forms of industrial instrument(s) should apply to the individual enterprise, employers must have regard to the viability and sustainability of each form in the changing industrial climate. In particular employers should have regard to the needs and agendas of their employees and unions which may purport to represent Them.

Jan 1, 1998

By J Sarvinis

The design and operational aspects of fluidised solids transfer-cooling devices will be discussed in this presentation. The devices include air slides and fluoseals (also called seal pots, loop seals, etc), which are widely used in metallurgical plants and other processing plants. Cooling can be achieved while solids are transported in the solids transfer devices. The units combining solids transfer and cooling provide compact and clean plant layouts and also reduce capital and operational costs. Fluidised devices provide excellent gas-to-solids and gas/solids-to-surface heat transfer rates, hence high cooling efficiency. Fluidising gas, such as air, nitrogen or other gases, can be used as direct cooling mediums. Coolants such as water, steam and other liquid or gas cooling fluids can be used as indirect cooling mediums via tube coils immersed in the fluidised solids. The fluidised transport devices share some common features with fluidised bed equipment. The air slide is similar to a linear fluidised bed while the fluoseal is similar to a circular fluidised bed. Therefore fluidised bed design techniques are applicable to the design of the air slides and fluoseals. The heat and mass balance and temperature profiles of the devices concerned will be discussed in the presentation. The design criteria and operational philosophies of the critical components such as tuyeres and air spargers will also be discussed.

Jan 1, 2006

By P D. Munro

The Mine to Mill concept, as it has become known, is a philosophy which is being increasingly embraced by mining companies committed to increasing their profitability through better integration and global optimisation of their mining and processing operations. Autogenous (AG) and semi-autogenous (SAG) mills are the principal primary grinding devices currently in use, their performance is particularly sensitive to feed size distribution. Most efforts to-date have centred on modifying and controlling the run-of-mine (ROM) size distribution to maximise grinding mill throughput. The complexity of the interaction between ROM size distribution, primary crusher product and AG/SAG mill performance precludes the trial-and-error approach as an effective means of determining the optimum blast-induced fragmentation size distribution. To overcome this limitation, the Julius Kruttschnitt Mineral Research Centre (JKMRC) has developed modelling and simulation techniques that are able to accurately reproduce both the fragmentation processes during blasting and the subsequent performance of the comminution circuit. These models are tailored to suit local ore types, rock structure and comminution circuit design and calibrated using high quality field data. MIM Holdings Limited (MIM) have been particularly active in the Mine to Mill area and have instituted optimisation programs at three of their associated base metal operations viz Alumbrera, Ernest Henry and the Mount Isa Mines. This paper describes these programs with particular reference to the data acquisition and modelling phases, the predictions of potential productivity gains and the extent of the realisation of these gains to-date.

Jan 1, 2000

By Roberts JD

The design and installation of a major on-line stores and purchasing system, with built-in maintenance reporting and plant register capabilities, needs more than just close attention to computer design details. When the system must be available almost 24 hours a day to a number of mine stores sites, and is used by a variety of mining staff including engineers and stores clerks, as well as by remote purchasing and office staff, then simplicity of use, availability, fast response times, and other human factors become vital. Critical aspects include easy to use screen design, involving a change from the traditional hierarchical menu system, and fallback and recovery to the last transaction. Business, people and systems objectives need to be established at the preliminary design stage, so that results can be measured and corrective action taken. The amount and type of user involvement and training, at all stages from initial design to systems tuning, has a major effect on people wanting to use the system. Active user participation in systems design, data definition and collection, and use of relevant training material is needed. Project management and design problems can arise in working with database oriented computer staff, and certain design features are found useful in ensuring a responsive, robust overall system.

Jan 1, 1983