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By Ellyett C. D

This paper is an appraisal of the application of optical-mechanical-scanners operating in the non-photographic infrared wavelengths (3-5 and 8-14 micrometres) to mineral exploration in Australia. Pundamental principles of the operation of airborne scanners and their data output, thermal infrared (IR) imagery, are summarized. It is contended that thermal IR imagery often depicts the distribution of electromagnetic radiation emitted from earth surface materials better than aerial photographic techniques because optical-mechanical-scanners sample wavebands which straddle the wavelength peak of earth surface emission. To illustrate the geological features which such scanners can depict, reference is made to thermal IR imagery of a number of areas in Australia where the technique has been applied for exploration purposes. The images demonstrate that this technique can detect structural features like faults and folds, stratigraphic data by distinguishing different rock types and delineating their

Jan 1, 1973

The patterns of occupational health pro- grammes in mining and metallurgy are discussed in relation to the impact of chemical and phy- sical hazards on the health of workers in these fields. Mining and metallurgy are quite unique in that their history and practice embrace virtually the total spectrum of occupational health problems and hazards as understood today. A panoramic concept of the possibilities would comprise the following fields: 1. The Pneumoconioses or Dust Diseases. 2. Physical stress due to exertion, and exposure to heat and humidity in deep mines. 3. The toxic effects of various metals in the mining of ore. The most obvious are lead, mercury, arsenic and manganese. 4. Diseases associated with mining. These include leptospirosis, ankylostomiasis and mycotic infections of the skin. 5. The Beat Diseases of coal miners working in narrow seams. 6. Illumination problems and miners nystagmus. 7. Geographical and climatic problems

Jan 1, 1975

Roadheader tunnelling machines have been used in Australia by both mining companies and contractors involved in the mining and con- struction industries since the early 1970's. They have both advantages and limitations, and this paper discusses machine excavation from the point of view of a contractor who has both reaped the benefits and suffered the conse- quences of using roadheaders. The paper also includes brief descriptions of three projects tackled by roadheader, all the projects being Declines.

Jan 1, 1987

The fundamental natural ingredient of any mining development is an ore reserve. The classical definition of an ore reserve has both technical and commercial components, each involving elements of risk. By definition the desposit must contain mineral values which are "extractable at a profit". Metallurgy supplies a vital link between these two basic requirements of a successful mining project; the metallurgical input establishes the process by which the contained minerals may be recovered and converted into marketable product(s).

Jan 1, 1983

Some of the problems of flotation, un- Solved in the mid-1950s, and possibly still unsolved today, are discussed with emphasis on dynamic aspects. These prob- lems include the nature of the air-water interface, particle-bubble contact and bubble attachment, and the effect of par- ticle size. Questions are also raised on the possible influences of the variability of minerals on flotation, particularly variations in composition and in foreign inclusions, both solid and fluid.

Jan 1, 1984

The patterns of occupational health pro- grammes in mining and metallurgy are discussed in relation to the impact of chemical and phy- sical hazards on the health of workers in these fields. Mining and metallurgy are quite unique in that their history and practice embrace virtually the total spectrum of occupational health problems and hazards as understood today. A panoramic concept of the possibilities would comprise the following fields: 1. The Pneumoconioses or Dust Diseases. 2. Physical stress due to exertion, and exposure to heat and humidity in deep mines. 3. The toxic effects of various metals in the mining of ore. The most obvious are lead, mercury, arsenic and manganese. 4. Diseases associated with mining. These include leptospirosis, ankylostomiasis and mycotic infections of the skin. 5. The Beat Diseases of coal miners working in narrow seams. 6. Illumination problems and miners nystagmus. 7. Geographical and climatic problems

Jan 1, 1975

By Milawarma E, Cusack C

The Sapan Dalam coal deposit of Indonesia consists of ten steeply dipping seams with thicknesses varying between 0.1 and 3.5 m and split by shale, clay, silt and sandstone. The area contains four faults dipping about 75¦ with four to 85 m vertical displacements. The complex nature of the deposit coupled with limited 27 exploration drillholes at an average spacing of 200 m made it difficult to create a realistic geological model. A three-dimensional gridded seam model gave a fair representation of the deposit. Attempt to create an optimum pit using the WHITTLE 3D pit optimiser proved unsuccessful since the pit optimiser is restricted to standard regular or fixed blocks. The gridded seam model was converted to a fixed block model prior to the optimum pit design. Smoothing and pit base controlling were also introduced to obtain a smoother pit. A mining scenario produced 3.6 million tonnes of coal, 28.4 million bcm of waste and US$18.1 million revenue.

Jan 1, 1995

By Hutchings AA

This paper describes MIM's experience in arranging and executing project financings for coal projects at Oaky Creek and Newlands and Collinsville and the port facility of Abbot Point.The financings had their origins in the late 1970's and culminated with the opening of these projects during 1983 and 1984.MIM's financing developments therefore span an important period in the development of resource projects in Australia.Resources projects have been growing in both scale and complexity of financing requirements.

Jan 1, 1985

Mining education in Ballarat has a long and proud history dating back to the 1870s. Today the School of Engineering continues this tradition at the University of Ballarat. The recent review of Tertiary Minerals Education by the Minerals Council of Australia has questioned the current situation regarding Minerals tertiary education in Australia and recommendations have been made regarding the future of minerals tertiary education. This paper initially examines the original recommendations made by the Minerals Council of Australia and assesses subsequent changes made to these recommendations. Secondly the paper outlines the future shape of mining education in the light of these recommendations given that they are implemented. Finally the future delivery of mining education is discussed, particularly with respect to the impact of modern technologies.

Jan 1, 2004

The continuously growing coal mining industry of India presently includes shovel dumper combinations in open cast mines, sometimes with dragline mining of overburden, together with the whole range of longwall and bord and pillar underground mining, continuously undergoing fuller mechanisation. This transition from "low tech" to "high tech" systems is now monitored for reliability and provides bases for comparisons of downtime relative to age and make of equipment, whether imported or indigenous, including spare parts, as well as frequencies of particular failures to allow analysis and progressive improvement. Varying geologies complicate technology and equipment requirements, especially in underground mine,s with minimal technological standardisation, but now, reliability in South Eastern Coalfields Limited has been given more importance and superior technological back-up is being developed.

Jan 1, 1991

By N R. Johnson

The overland conveyor at the Los Pelambres mine in Chile is designed to move 8700 t/h of material over 12 km at a speed of 6 m/s while descending 1400 m. The conveyor, which is divided into three segments, is equipped with a braking system that must bring it to rest without producing excessive stresses in the conveyor belt. Retardation and gently stopping a mass of 250 t requires retardation times in the order of 60 seconds. Brakes that can provide this performance require sophisticated controls as well as very high heat absorption capacity. This paper describes the thermal analysis of the braking system, which required the use of novel materials to meet the arduous duties imposed on the callipers and discs.

Jan 1, 2005

By J A. Rumball

Measuring cyanide in the leach liquors associated with high copper and/or sulfide ores is a non-trivial exercise. It is well known that copper complexes with cyanide and reduces the amount of cyanide available for gold leaching. What is not so well known is that the rhodanine end point overestimates the amount of cyanide available for leaching in the presence of copper. Sulfide ions also interfere with a rhodanine end point titration, although this is less of a problem as the black silver sulfide precipitate formed clearly indicates to the operator that something is wrong. Thiosulfate, which forms readily from the alkaline oxidation of sulfides, causes an overestimation of the cyanide available for leaching due to the formation of Ag(S2O3)-. The net result of these observations is that rhodanine is rarely of value as an end point indicator in complex solutions. It generally overestimates the amount of cyanide available, providing plant metallurgists with a false sense of security. Potentiometric titrations are generally much more capable of accurately measuring cyanide in complex solutions. The interfering effect of copper can be resolved and it is even possible to estimate the copper concentration using the inflexions associated with the titration of CN- + Cu(CN)43- versus Cu(CN)32-. Using the potentiometric method sulfide ions can be determined before the cyanide measurement is made due to the formation of AgS2, although the electrode will foul with repeated measurements. Thiosulfate can also be distinguished from cyanide with a potentiometric titration. Rhodanine and potentiometric titrations are both affected by the pH of the liquor. At pH 9.2 half the cyanide will be present as CN- and half as HCN(aq) with only the CN- being titratable. This does not hold in the presence of a buffer active around pH 9. In the presence of sufficient buffer, both the CN- and HCN(aq) are titrated. Ca(OH)+ may buffer the pH when large amounts of lime have been added.

Jan 1, 2007

Polyacrylamide flocculating agent has been used in the Leaching Division of the Risdon Works of the Electrolytic Zinc Co. of Australasia Ltd since October, 1960. Since the introduction, the.: number of thickeners in use in the continu-ous thickening stage has been reduced from eight to three; there has been an increase of 25% in throughput and a reduc-tion of solids in.:thickener overflow from 3-4 gòpòl . solids to 0.5 g.p.l. solids. Reagent addition has been at the rate of 0.25. lb SEPARAN, NP10 per ton solids.Additionally there has been a gain of 3% in current efficiency as the direct result of the addition of SEPARAN NP10 to purified cadmium sulphate solution prior to electrolysis for cadmium metal. A smoother deposit has resulted and it has been possible to increase deposition time between strip-pings from 47 to 71 hours. However, there has been a slight increase the lead content of the cadmium-metal produced.

Jan 1, 1963

The Century zinc-lead orebody was discovered in 1990 and contains sufficient reserves to sustain open cut mining at 5 Mtpa of ore for approximately 20 years. It is proposed to pipe mineral concentrate in slurry form 300 km from the mine to the port of Karumba on the Gulf of Carpentaria. The concentrate will be dewatered at Karumba before being transported off-shore to deeper water in a self-unloading shuttle vessel for transfer to export bulk carriers. The four main environmental issues that attracted attention during the impact assessment phase of the project were: the selection of Karumba as the export port, the use of a pipeline to transport concentrate, the risk of concentrate spillage in the marine environment, and aquifer drawdown in the vicinity of the mine. This paper discusses these issues with emphasis on the context of the relationship between the Pasminco Century Project and Gulf communities. Environmental safeguards are discussed, including those that arose out of the negotiations regarding Aboriginal native title.

Jan 1, 1998

One of the responsibilities of the Melbourne and Metropolitan Board of Works is to provide a sewerage system for the metropolis of Melbourne which now contains over 2.5 million people. In providing this sewerage system it was necessary for the Board to embark on a large tunnelling programme some 20 years ago. As a result of this extensive tunnel construction programme, tunnel boring machines and shaft sinking methods have been developed to cope with the soft ground and soft to medium rock found in the southern and eastern areas of Melbourne where the majority of the recent tunnelling has been carried out. While in the last few years radical changes in construction methods have not been made, development has continued and improvements have been made, which have enabled the Board to extend the limits of the ground conditions in which it can efficiently construct shafts and also tunnels with boring Machines.

Jan 1, 1976

By A Whaanga, A Doecke

The internal stratigraphy of the Marillana Creek palaeochannel Tertiary channel iron deposits (CID) in the Hamersley Province of Western Australia was initially defined in the 1980s and redefined as the Marillana Formation in the early 2000s. Recent drilling, open pit mining and field observations in the Western deposits at BHP Billiton Iron OreÆs Marillana Creek tenements have revealed some additional details on the extent and detail of some units of the Marillana Formation stratigraphy in this area. The drill hole data at Western 1 South has identified a number of features either not previously documented in this area or whose significance has not been adequately recognised, including a denatured zone at the base of the Upper CID of the Barimunya Member, and variations in the lithology within the Munjina Member at the base of the channel. Additionally, the Western 4 pit walls show evidence of a significant near-surface clay horizon and overlying CID, which are suggested to be the equivalent of the Iowa Eastern Member in the Eastern deposits. The deposition of this unit was most likely driven by a regional climatic disruption rather than a change in sediment source area alone. The nature of the Weeli Wolli Formation-derived goethitic peloids in the Western deposits may explain the more extensive denaturing in the Western Lower CID of the Barimunya Member. In contrast, the more robust nature of the haematitic-cored pelletoids in the Central and Eastern deposits has resulted in a less denatured Lower CID in these areas. Such work reveals the value of and need for geologistsÆ ongoing face mapping observations and detailed drill hole logging, and cautions against not querying previously accepted interpretations.

Jan 1, 2007

During the century past geologists have discovered an extraordinary range of mineral resources. It is somewhat surprising, in view of their success, to look back and find that geologists have been concerned through the entire time about the adequacy of resources to meet future needs. They continue to express concern. The basis of their concerns seems to rest as much in social issue as in evaluations of geology.Demand for mineral resources is driven by population and by per capita consumption. Both have grown steadily over the past century, and both continue to rise. In 1890 the global population was about 1.7 billion, people. It has now exceeded 5 billion and the growth rate is such that by the year 2000, the global population will be between 6~ and 7 billion. Demographic projections suggest the global population will approach 12 billion before a steady state is reached dnrino the centiirv ahead

Jan 1, 1990

Natural Gas has been available in New Zealand for twenty years. During that time the gas share of the energy market has grown and now natural gas forms a significant part of New Zealand's energy scene, helping consumers to achieve a higher standard of living, and reducing dependence upon imported oil.Natural gas is now used for petrochemical manufacture and power generation in addition to direct supply to consumers.As concern for the environment continues to build, natural gas will have an increasingly important role to fill in these markets. This paper sets out the background to the development of natural gas in New Zealand and identifies the current markets. It then looks at those matters which are likely to influence the role of natural gas in the 1990s.

Jan 1, 1990

By P Campi, M Dodds

The EastLink project is a 39 km tollway to the east of Melbourne and includes twin three-lane 1.5 km driven tunnels. The hard rock tunnels are being built to avoid passing the motorway through the Mullum Mullum Valley to help preserve the unique flora and fauna in the area. This paper describes the process of transferring the support requirements from the ædrawing boardÆ to the tunnelling face by integrating the temporary support design with the contractorÆs tunnel excavation and support procedures, including sharing of responsibility between the designer and contractor for selection of the support type and the production of a project specific rock mass classification system to enable more objective determination of ground conditions. The methods developed during the design phase incorporated a formal system of reviews, support selection and feedback by monitoring tunnel and ground responses. During construction, the process was implemented using a set of simple documentation and regular structured communication between the contractor and the designer.  

Jan 1, 2008

By Grieve BL

For a blast to be successful both heave and fragmentation must be satisfactory. Amongst the major factors influencing blasting are rock properties. This paper considers the effect of rock density on fragmentation and heave and how better results can be achieved in dense ore. Patterns which increase the heave and give better fragmentation are examined and the application of theory to the blasting of the Dales Gorge Haematite, density 4.2 - 4.5 t.m.,3 is then discussed. The drilling of staggered patterns instead of square patterns and a shallower 'V' initiation system has given better heave and fragmentation. This practice has re- duced backbreak and improved toe conditions; these factors have resulted in increased load ing rates. There has been an increase in the lump/fine ratio which is consistent with the theory although other factors such as ground conditions could have contributed.

Jan 1, 1978