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By M Thomas, M Caccetta, C Laukamp, A Hacket, M Jones, A Rodger, M Verrall, R Hewson

A mineral systems approach was used to interpret precompetitive airborne mineral mapping geoscience data for iron oxide copper gold (IOCG) exploration in the Starra area, Eastern Succession, Mount Isa Inlier. Selected minerals were chosen to map possible source rocks/fluids as well as intersecting structural/fluid pathways that could have transported mineralising fluids into domains of contrasting rocks/fluids where there was potential for physicochemical gradients to precipitate metals. Ferric and ferrous iron contents and white mica abundance were useful mineral criteria to identify theMount Dore Granite of theWilliams-Naraku Batholith as a potential source of æoxidisedÆ fluids rich in Fe, K and potentially Cu-Au. The Mount Dore Shear Zone (MDSZ) intersects the western margin of this granite with the highest contents and changes in composition of the white mica are peripheral to this contact within the granite. This together, with the fact that the entire N-S length of the MDSZ in the study area (~16 km) is abundant in white mica are evidence of K-rich fluids had preferentially moved along this pathway. To the south, the MDSZ intersects a domain comprising massive ironstone bodies as well as numerous graphitic horizons. This interpreted æreducedÆ domain is well mapped using the æopaqueÆ mineral products, as well as by white mica, which is pervasively developed and extends 2 km either side of the MDSZ fault into the meta-sedimentary sequences. The chemistry of this white mica also changes progressively away from the MDSZ, becoming more Si-rich (longer wavelength) towards the contact with massive ironstone bodies in the west and the graphitic units in the east, both of which represent sites of known Cu-Au mineralisation. Beyond these contact zones of interpreted æoxidised fluidsÆ with reduced rocks/fluids, there is either a rapid change to Si-poor white mica and/or no white mica developed, ie major æchemicalÆ gradient change. These mineral mapping results provide evidence for a direct link between possible source rocks and sites of IOCG metal deposition as well as extending the associated alteration zonation which had previously been mapped/published at the metre-scale to the kilometre-scale. An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation.

Jan 1, 2008

The society in which we live is one of change, and we professionals are part of that society. The importance of this simple and obvious statement is often overlooked. My Presidential Address examines the question: can professionalism survive in our changing society?There is ample evidence to show that our society is changing, and that the rate of change is exponential. This rapid and accelerating rate of change is what Alvin Tomer refers to as "future shock". Rapid change means that we do not have time to become accustomed to what is happening around us and to feel comfortable with it; the greater the rate of change the greater the discomfort. The effect that this has on people is varied; the change may be either expected or totally unexpected.The rate and extent of change in society is not the same for all countries nor for all industries or occupations. Change is more rapid in Japan, Korea or Taiwan, than in Australia. It is more rapid in our cities than in the bush, more rapid for professional businessmen than for farmers. In our minerals and petroleum industries, we are still adjusting to the great changes that have taken place over the last fifteen years. In the past, products from our industries were sold on a free and open market. Today, mineral development and production in most undeveloped countries and some developed countries is manipulated for political, social and economic reasons. Changes of this nature have had a devastating effect on the operations of established mineral producers in the democracies.Because of the accelerating nature of change, we must recognise that the past is not a reliable guide to the future.Although extrapolation of the past into the future is a basic ingredient of commercial survival, extrapolation is less and less reliable.I borrow from others in quoting the Irish proverb: "The future is not what it was".The future is where our business lies and most of us at this Conference must endeavour to understand it and adjust to it. I believe in the old adage that:You can't know where you're going if you don't know where you've been and where you are at.There are a number of major factors which have created change within our social, economic, and industrial environment in recent years.

Jan 1, 1985

By P C. Hagan

Production scheduling is often reliant on an estimation of a mineÆs trucking capacity. While this mechanistic approach is relatively simple, it often over-estimates actual throughput resulting in under-utilisation of downstream process and a shortfall in revenue. An alternate approach has been developed that recognises the interdependency between processes in the mine production system including materials loading, haulage and crushing. This approach incorporates a heuristic model based on queuing theory that accounts for the variability in performance of individual processes and that this paper presents the results of a study comparing the conventional approach to mine scheduling with a capacity constrained model at a large open cut mine having a truck and shovel fleet. The capacity constrained model consistently predicted a lower material throughput compared to the conventional approach. Differences in throughput between the two approaches were found to increase with loading time, for example when loading time exceeded 3.9 minutes there was a shortfall of up to 40 per cent in estimated throughput. Longer travel times tended to ameliorate any differences. When applied to a mine schedule that extended over a two and a half year period, the difference was equivalent to a shortfall of nearly eight per cent in total material movement.

Jan 1, 2007

Tokyo Metropolitan Government designs the stormwater storage plans in underground, as a measure of flood control in completed urban district and improvement of combined sewarage system. This time, introducing those plans, we report about IKEJIRI and SIN-KOMAZAWA STORAGE TRUNK LINEs design and construction. They are located in Meguro river basin of the Morigasaki drainage area. Both storage trunk lines have capacity to store 15O,000m3 of stormwater. They are in use for countermeasure of flood till Meguro river's strengthening (intensity 50 mm/h) is ended. And after the strengthening, they will be in use for improvement of river water quality, through the storage of combined sewage and first runoff, which, otherwise overflows weirs and flows to river in a rainy day. These storage trunk line's full length is about 5700m. Boring diameter 66140 mm (f = 2672m) and 47800 mm (I = 2866m) of these tunnels are constructed by Mechanical Shield tunnelling method. And boring diameter 3600 mm x 4000 mm (R = 180m) is constructed by NATM tunnelling method. We began works in 1983, and have a mind to complete in 1987.

Jan 1, 1987

I take it the character of addresses to conventions, should, following precedent, avoid details, and treat subjects rather from a philosophical point of view so far as they will permit.In the subject about to be treated on, an endeavour will be made to find here we stand as regards the past, in order that we may the better, hope to look correctly in the direction to be followed.It may be assumed that the main object of the Institute is to forward mining interests and the ways in which engineers can aid those interests are many. If all of us were to try to follow many of those interests we should become like" jacks of all trades and masters of none". Mining engineering is consequently subdivided, all are necessary to the common end, and it is on one of those divisions I have undertaken to address you. The subject or steam pumping is a large one, and I regret, not having received such longer notice as would have enabled me to do better justice to the subject, and more respectful regard for yourselves. I must, however, under the circumstances, crave your generous consideration, and hope the topics mentioned may furnish material for discussion and future papers of far more value than this one, Ind.eed, the subject is so illtimately and historically associated with mining that if treated on its merits would be highly interesting or could be made so in more capable hands.

By Gillies A. D S, Lee A. H

The major operational objectives of a mine water resource management system (WRMS) are to supply the water needs of the mine and mill, to minimise disturbance to mining due to rainfall flooding or seepage and to dispose of excess water. Historically, company management have placed a significantly lower emphasis on managing the WRMS as compared to managing production. Changing Government legislation concerned with the disposal of water from mine sites is, in many cases making mining companies look more closely at how they manage their water. For example, within the next few years it is likely that prior to mining approval by the Government, mining operations will have to submit water management plans/budgets and contingency strategies in addition to operational plans. While the formulation of a comprehensive water management plan/budget is an additional cost to the company at the mine establishment stage, such plans can be beneficial to the operation in the longer term.The two keys for the efficient design, operation and development of a WRMS are the establishment of written goals which have managerial priority and secondly, access to appropriate good quality data. Managerial priority towards the WRMS will increase as a consequence of the education of mine operators in the benefits to the operation of good WRMS management or less desirably as a requirement to meet Government legislation. The collection of appropriate WRMS data is a more complex issue and to obtain information efficiently and cost effectively relies on the clear definition of the data application.

Jan 1, 1992

By C Philander

The West Coast of South Africa is well known for its placer gem quality diamond deposits and also associated with these hosts of Cenozoic unconsolidated marine and aeolian sand and gravel are significant concentrations of heavy minerals. Exploration for economic concentrations of zircon, ilmenite and rutile along the coast started in the mid-1980s. This resulted in the discovery of an inferred 1.6 billion tonne resource with a grade of ten per cent total heavy minerals (THM), which developed into the Namakwa Sands Mine, a world-class producer of heavy minerals. Several other resources, including satellite deposits proximal and distal to the mine area, extensive diamond mine dumps and present day beach placers, demonstrate the vast heavy mineral potential along the West Coast. The favourable gangue to economic mineral ratio, a higher zircon content compared to other similar deposits, relatively lower U+TH content of zircon, low slimes content and effectively pristine low chromium-manganese ilmenite of these deposits, render them attractive exploration targets. Negative factors that will affect conventional mineral beneficiation and liberation include secondary mineral coatings and the regional coastal development of several layers of superimposed duricrust. The economically attractive heavy mineral assemblage along the West Coast is the result of erosion of the proximal, gneissic Namaqualand Metamorphic Province and mature Table Mountain Group sandstone, concentration by marine and aeolian processes and preservation under arid climatological conditions over a period of more than 100 Ma.

Jan 1, 2008

Productivity of mines can be improved by taking fewer, but larger blasts. The initial blasts taken in starting a mining block are restricted by the low amount of void or space to fire into. Block cave mines are using a blasting technique to blast areas that have less than the normally accepted minimum void to establish drawbells for their orebody development. This technique used in block caving mines can be used to improve productivity in mining operations that utilise other mining methods. Some larger blasts have been done in mines, using open stoping methods, which have had void ratios as low as 13 per cent. This has been possible with the use of the explosive gases to transport the broken rock out of the area normally considered to be available to blasts. This trapping of the explosive gases in the broken rock has allowed rock to be moved over 30 m, horizontally, to allow for more void to be available in the blast area. This gives the necessary void ratio allowable to fire larger blasts. This paper will discuss the blasts where this technique has been used in mines to increase the tonnes fired in low void situations. It will also discuss where this type of blasting may improve the productivity of underground mines. Figure 1 shows the how explosive gases have enabled the broken rock to flow out of a draw point without the typical air blast and fly rock that would normally cause a rope suspended sign to be damaged beyond use.

Jan 1, 2008

By F A. Rosyid

Mineral resources are national assets which must be capitalised for national development. Those assets should be transferred into real economic capital and then into social capital to achieve national/regional prosperity. Successful development in the mining industry will depend on the correctness in determining the role of mining industries for regional development. Using the context of sustainable development, this paper will analyse the concept and process of mining industry development as an accelerator to achieve regional sustainable development, using the mining operations of PT Newmont Nusa Tenggara (PT NNT) in Batuhijau, Sumbawa Barat Regency as a case study. In the premining activity phase, Sumbawa Barat was dependent on the agricultural sector. Agriculture contributed around 40 per cent of the regional gross domestic product (GDP). Meanwhile, in the activity phase, mining became the sector with the biggest contribution to regional economy. From its operation in Batuhijau, PT NNT contributed around 70 per cent of the regional GDP per year since 2001. In year 2000, the GDP had increased 170 per cent from its figure in 1999. However, due to its depleting reserve, PT NNT will finish its activity in Batuhijau by year 2015. Consequently, the Government of Sumbawa Barat Regency must develop other sectors in the post-mining phase to sustain economic development. Based on location quotient (LQ) and input-output analyses, Sumbawa Barat should develop its priority sectors, ie agriculture, trading and hotel, services and construction to achieve sustainability after mining life. Development of these non-mineral sectors is expected to sustain economic growth in the region.

Jan 1, 2008

By G W. Croft, L E. Krause

The current copper ore handling systems in use at Xstrata CopperÆs Mount Isa Copper Operations are up to 33 years old and have hoisted over 160 Mt at a rate of around 6 Mtpa. The mineÆs production profile is increasing in line with the optimum life of mine plan to over 6.6 Mtpa, which requires a system utilisation and reliability above that previously achieved. Copper ore is hoisted up the U62 shaft, which forms the central part of the U62 ore handling system. In theory this system can cope with the duty planned if the bottleneck is only the U62 winder. To achieve the planned production rate will require increased focus on reliability of each component in the ore handling system so that ore is available at the shaft for hoisting whenever the shaft is available, and the shaft is available for the maximum practical time. Increased availability will be achieved through the outcomes of the study of each component in the U62 system, and the internal ore handling systems that deliver ore from as far as 2 km laterally and 700 m vertically from the U62 shaft. The true capacity of each component is being determined and current performance is being measured with the aim of improving performance through root cause analysis and engineering out the causes of delays. The program began in March 2004 and this paper describes the progress achieved as of April 2005.

Jan 1, 2005

By H Rouhullahi, E B. Veshki an, R Kottnauer

The Galandrud coalfield is located approximately 20 km south from the coast of the Caspian Sea, Ruyan town, on the north slopes of the Alborz mountain range, in the elevation between 500 m (the Galand River valley) and 1350 m. For the time being, 32 coal seams (generally of small thickness û 0.8 m on average) have been recognised within the. On the other hand 72 coal banks of balanced properties have been included in reserve calculation, which means that some of the seams consist of several banks. The general dip of strata belonging to the south limb is about 30¦ to the South (with drags close to the south overthrust, where the dip reaches 85¦), while the dip of beds at the north limb is rather steep and usually between 45 to 75¦ to the North. The coal quality is in a rank of high volatile bituminous coal. The steep dip, unstable lithological development, complicated tectonics and comparatively lower coal seam thickness are the characteristic features of the Galandrud deposit. Environmental protection of this area makes exploration and exploitation more complicated. During mine exploration several adits were driven at three levels with 50 m vertical distances. About 4000 m of gates and crosscuts were up to now driven. During mining test the down-cut mining method (with one cut), the strike cut mining method and the down-cut mining method with two cuts were tested. The paper describes outlines for the selection of mining methods on the base of classification of the effective hangingwalls and footwalls, hazards of mining operations, and possibilities of the mechanised mining.

Jan 1, 2003

This is the second of a series of papers dealing with Geology in Exploration. The first, published by the Australasian Institute of Mining and Metallurgy, Proceedings Nos. 143-144, 1946, was written as an introduction to the subject and employed the exploration geology of the Cobar field to illustrate the prospect thinking. This paper will be concerned with the problem of ore repetition in depth and borrow its- example from the Mount Lyell copper field. The writing will be taken up altogether by the example. Nevertheless the intention remains to develop the subject in terms of its wide interest and application.The Mount Lyell field possesses large actual and prospective resources within, and in the vicinity of, the known deposits. This paper does not bear at all on these accessible ore reserves and tangible prospects. There is also in this area evidence of deep ore. The possibility is of little practical interest at present. But the picture of ore repetition, exemplified by the Mount Lyell field, does matter now to the outlook on exploration in this country. For once this essential feature of ore occurrence is widely understood there may develop, on the scale warranted, the search for major deposits which do not outcrop but which are still at shallow depths because of the part erosion plays in this story of concealment and exposure of ore. Also there is the chance in some fields (including Mount Lyell) of a second harvest of orebodies within mineable depths. This exploration goal, introduced in the first paper, will appear more clearly as the Geology in Exploration series is written up. Here the concern is to show the character of the geological evidence which points to the occurrence and recurrence of ore in the earth's crust, the picture at the foundation of this exploration scheme. There is considerable information in the Mount Lyell area of the structures...

Jan 1, 1947

By W A. Ducker, R-H Yoon, M Mao

Froth flotation relies on an attractive force between a particle and a bubble to selectively extract particles from a mixture. The range and magnitude of this attractive force is an area of ongoing investigation. We describe measurements of the effect of dissolved gases on the long-range attractive surface forces between a silica plate and a glass sphere in aqueous octadecyltrimethylammonium chloride (C18TACl) solutions. The measurements follow on the work of Sakamoto et al (2002) who have concluded that long-range interactions occur in air-equilibrated surfactant solutions but not in degassed solutions. In the present work, we have measured attractive forces that have a much larger in magnitude than the expected van der Waals force in solutions that were degassed by the same procedure used by Sakamoto et al (2002). We find that the forces are most attractive at 5 + 10-6 M C18TACl, which is close to the charge compensation point (ccp) of the glass sphere. At this concentration, the attractive force decays exponentially with distance and the decay length is 34 in air-saturated solution, and 38 nm in degassed solutions. In both air-equilibrated and degassed solution, the force is quite sensitive to the concentration of surfactant. The force is also sensitive to the pH. We note that our degassing procedure increases the pH of the solution from about 5.7 to 6.6 (presumably by removal of dissolved CO2). We find that the forces measured in degassed solution can be reproduced by using a solution that was equilibrated in air, then the pH was increased by addition of NaOH. Therefore, we conclude that the main effect of degassing in our experiments is to raise the pH. We show that the range and magnitude of the attractive force decreases in the presence of salt (NaCl). This suggests an electrostatic mechanism for the attraction. Possible mechanisms for the attractive force are examined, including the mechanisms that rely on a patchy coverage of surfactant on the silica surface.

Jan 1, 2005

By C F. Nichol, L Smith, R D. Beckie

A better understanding of the hydrogeology within mine waste rock and cover systems is essential for the quantification, prediction and prevention of metals loading to the environment surrounding waste rock piles. The effect of surface condition on the internal flow mechanisms within an intermediate-scale constructed waste rock pile is being investigated at the Cluff Lake Mine, Saskatchewan. Changes in the water balance, the outflow distribution and water residence time have been observed in the waste rock pile following successive modifications of the surface condition. The three year old, run of mine, free-dumped surface was ripped to a depth of 30 cm to 40 cm, and levelled in October of 2001. In August 2002, a 10 cm to 15 cm cover of compacted waste rock was placed on the pile. Outflow, precipitation and run-off data collected during natural and artificial rainfall events have been used to quantify the maximum infiltration rate, and the spatial pattern of discharge and cumulative volume of water that infiltrated into the waste rock under each surface condition. Infiltration data together with the outflow data provide a basis to address the residence time of water within waste rock and the dominant flow mechanisms for different surface conditions. With a free dump surface spatially distinct wetting fronts are observed at the base of the pile that vary in flow rate by an order of magnitude (measured at a 2 m by 2 m scale) and in time by up to a week. Following ripping and levelling, similar cumulative outflows were observed, but the magnitude and arrival time of wetting fronts changed across the pile. A decrease in outflow volume, a decrease in infiltration volume, a two-fold increase in the response time of wetting fronts and a more spatially uniform distribution was observed following placement of the compacted surface layer. Based on preliminary data, the internal structure appears to be the dominant factor controlling outflow variability.

Jan 1, 2003

The Curragh mine has complex operating conditions. The mine operates in four seams to produce two coal qualities and is divided into five pits which have different qualities and coal preparation characteristics. The combination of all of the necessary controls to achieve maximum resource utilisation has necessitated the development of suitable software to assist the quality control engineering function. The required software had to be able to plan the optimum yield of coking coal whilst achieving the quality parameters for the coking coal and co-produced steam coal. The program has been designed to evaluate all of the mine faces available for coking coal production. The optimisation of coking coal production is planned and co-produced middlings steam coal determined. The optimum steam coal product is determined using the middlings in combination with bypass production.The computer software to carry out these functions has been designed by using an exploration data base as the raw data source. The program accesses this data and uses a coal preparation prediction program to determine the yield vs. ash relationship for each coal face. A linear program selects the optimum -combination based upon equal incremental ash values. The final output lists feed tonnages, coal preparation conditions, product tonnages and full coal quality data.

Jan 1, 1985

Recent exploratory work has greatly enlarged our knowledge of the geology of the sedimentary basins of Western Australia. The most pros-pective of these for oil explorati on are believed to be the Canning, Carnarvon, 'and Perth Basins.The search for oil. in, the Canning Basin has fora the most part been concentrated in" the western part, where four main structural units are now recognized - the Lennard Shelf, Fitzroy Trough, Jurgurra Terrace, and-South Cariizin.g Basin. Of these the Leonard Shelf may. be the'most prospective. The principal objective on the Shelf is the Devonian sequence, which in-cludes well'developed reef complexes. The Lower Carboniferous is regarded., as a further objective, as it contained small quantities of oil in theMeda No. I well.In the. Carnarvon Basin most explorati on has been conducted in the coastal belt of'Tertiary folding, especially in the Cape Range-Rough Range area. -The discovery of oil in the first test well. drilled.in the-basin - Rough Range no. 1 - raised great hopes, for the quick discovery of a ecmuercial field. However the other wells on Rough Range have been dry, and no discoveries have-been made in the-wells drilled on other anticlines.in the basin.

Jan 1, 1962

Mr. Chairman, Distinguished Guests, Ladies and Gentlemen. I was delighted to be invited, and to accept the invitation, to welcome to this specialist meeting on an intriguing subject, the local participants and - most importantly - the international contributors. Technical o analysis of blast furnace operations has for many years formed the basis of intense research throughout the iron and steel industry, world wide, because the efficiency of blast furnace operation estab- lishes the foundation for all subsequent processes in a steel plant. So much depends on the constant, efficient performance of iron melting units in relation to costs, quality, regularity of operations and reli- able delivery performance to our customers.

Jan 1, 1981

By Morland R, Peck R

The Joint Committee of The Australasian Institute of Mining and Metallurgy (AusIMM) and the Australian Mining Industry Council (AMIC) have published a Code for the Reporting of Identified Mineral Resources and Ore Reserves. The Code is the result of an initiative begun in 1971 to achieve industry self regulation of Resources and Ore Reserves reporting which resulted first in guidelines for reporting standards but which have now been incorporated in ASX Listing Rules as a Code with significant sanctions ensuring compliance. This paper describes the background to the Code, its key provisions, and comments on practical aspects of working with the Code and compliance issues.

Jan 1, 1990

By Dawes C. A, Mitchell R. A

A process control strategy has been developed for the lead circuit of the lead- zinc concentrator at The Zinc Corporation, Limited (ZC), Broken Hill, Australia. The general aims of the control system were to produce a final concentrate with a zinc content below a certain limit and, at the same time, obtain the highest lead recovery possible. As presently arranged the system involves control of the cleaner feed mass flaw by cleaner diverter tray manipulation and control of xanthate addition based on per cent lead in feed. Generally this approach works well but for abnormal conditions such as very high or law pH the system requires further improvement.

Jan 1, 1983

The discovery of magmatic nickel sulfide mineralisation within the Musgrave Block of Central Australia, in a region which has received virtually no exploration since the early 1970s, promoted a pegging rush throughout the region and provided a significant boost to the investor interest in resources sector companies. The discovery proved a significant success for the application of generic models for major magmatic nickel-copper sulfide deposits. The entry of junior explorers to the region is the principal mechanism by which the region will be explored, although significant social and physical challenges will impact on the ability of explorers to maintain investor confidence in the region.

Jan 1, 2002