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By Zwaan J, Kepa J

Ok Tedi mine has become one of the major copper producers in the world. In the process of becoming of age, it overcame the challenges of operating in a locality which is young in geological terms, experiences very high rainfall and has a topography which gives rise to frequent landslides. This paper discusses some of the geological, mine and geotechnical engin- eering aspects of the Mt Fubilan ore deposit.

Jan 1, 1991

The Calypso geothermal field, mapped by the R V Sonne (cruise SO-135) in 1998, includes four main sites, the Northern Vent Area (centred on 37¦ 36.7'S, 177¦ 06.2'E, area 1.5 km2), Central Vent Area (37¦ 39.4'S, 177¦ 05.2'E, 1 km2), Southern Vent Area (37¦ 41.7'S, 177¦ 06.0'E, 1 km2) and Mercury Vent Area (37¦ 41.3'S, 177¦ 07.3 'E, 0.5 km2). Hydrothermal activity at the vent sites is controlled by minor, sub-parallel NE-trending normal faults. Gas bubble trails (C02) and shimmering hot water vent from fractures and joints between large blocks of silicified volcaniclastics and in depressions in the sediments at the base of these outcrops. Measured maximum vent temperatures are between 180¦C and 201¦C. Venting fluids are at, or just below, boiling for water depths of 200 m. Rock samples recovered by dredge from the sites include massive anhydrite, clay-altered pumiceous ash, silicified volcaniclastic sediments and volcaniclastic breccias cemented by sulphur. Clay-altered samples, dominated by randomly interstratified illite-smectite and accessory chlorite, indicate formation environments of 70¦C to 90 ¦C. Native sulphur is abundant throughout the samples. Fine-grained (<1 mm) disseminated pyrite and vein pyrite occurs in the clay-altered pumiceous volcaniclastics and argillites. In the Southern and Mercury Vent Areas, fine-grained orpiment, realgar and cinnabar have deposited in the sandy matrix of volcaniclastic breccias. Amongst the cinnabar, small (<2 mm) beads of native Hg formed on the surface of several rocks following their recovery. These samples also contained abundant light hydrocarbons, which coat the rocks with an oily sheen.

Jan 1, 1999

By Bibby P. A, Leupen R. A

A 24,300 tonnes per year state of the art Silicon smelter is being constructed for Barrack Silicon Pty Ltd at Kemerton, 20 kilometres north of the City of Bunbury in Western Australia. The plant is designed for the reduction of high purity quartzite lump to metallic silicon in two 27MVa Demag submerged arc electric furnaces. The primary reductant, a high purity charcoal, will be manufactured at the plant from locally sourced jarrah wood waste (Eucalyptus Marginata). Commercial silicon production is scheduled to commence in October 1989. Keywords: Silicon, Smelter, Quartzite, Furnace, Charcoal, Jarrah, Wood, Eucalyptus Marginata.

Jan 1, 1989

The title of this address was selected before I had an opportunity to consider in detail the matters that I would like to discuss. Accordingly, I chose a very broad subject-so broad indeed that it would be foolhardy for me to attempt to deal with more than a few aspects of it. I do not propose to touch. at all on the developments to date of our mining and metallurgical enterprises, beyond paying a sincere tribute'to the skill and enterprise of those who have established an international reputation for Australian mining and metallurgy. I would rather look ahead and discuss certain factors that will play a decisive part in the future development of our mineral resources. I do this in no dogmatic spirit, and I hope that my remarks may lead to discussions which will stimulate action where it is needed.In recent years my colleagues and I have been forced by circumstances to give consideration to problems in the fields of mining and geology, and in process metallurgy, which lie outside the scope of our own research work. People come to us with metallurgical problems because they know of no more appropriate place to go, and it is distressing to have to inform them that it is nobody's job to offer them advice and assistance. I want to suggest to your Institute that it should press strongly for the provision of properresearch facilities for the mining and metallurgical industries, such as aready exist in most enlightened countries. In such countries, those connected with the development of mineral resources are able to obtain information and advice from Geological Surveys, Mines Departments or Bureaux of Mines, which offer far more comprehensive services than are available in this country.Before discussing specific technical problems of the mining and minerals industries, I shall enunciate certain general principles that I believe should be followed in respect to the technical side of the development of all Australian industries. The problem can, I suggest, be considered in three parts-technical education production, and research. I shall confine my remarks mostly to the research aspect, for it is with this that I am most familiar.For the efficient development of any industry in Australia, it is essential firstly that We should learn what is going on abroad, and secondly that we should simultaneously conduct independent research. In the latter sphere the Governmeht'departments and the private companies' or groups of companies should have complementary functions, the former concentrating on problems common to a number of companies or industries, and the latter on their oWn individual problems. It is essential to the continued existence of Australian industry that both company and govern...

Jan 1, 1944

Real-Time Integration of Mining and Metallurgical Information for Efficient Use of Energy and Water

Sep 13, 2010

By G C. Sen

All mining and quarrying operations that employ blasting to fragment and move broken ground have a price to pay for æby-productsÆ such as vibration and noise. These æby-productsÆ cannot be eliminated but they can be controlled and modern blasting techniques have improved to the point that excessive environmental restrictions can be adhered to whilst maintaining acceptable production rates and quality. Accurate measurement is the key to control, and as the environmental limits are becoming tighter, the proper way to measure vibrations from blasting operations becomes an integral part of the mining or quarrying operations. The basic vibration monitoring system consists of a primary sensor connected to a data logger and computer software for the analysis of the signal received and recorded. Currently, as with all fields of measurement, much improvement has occurred over the past decade, and electronic devices are much more accurate and reliable. Data analysis has also improved considerably with the computing power that is available to field operatives today. Mounting the primary sensor has been often overlooked in supposed æstandardsÆ with procedures such as double sided tape, resting on a flat surface provided the vibration level is less than a given amount. But if it is worth going to the expense of the monitoring equipment and manpower, surely it is worth a little extra effort to ensure the primary sensor is coupled to the ground effectively. The primary sensor must move with the ground and measure this movement; so if the primary sensor is allowed to move without respect to the ground (ie poor coupling to the ground) then a false record of the physical event will be measured. This scenario can easily be a practical reality if the primary sensor coupling method to the ground is not effective. In this study a number of mounting methods were fabricated and connected to similar data monitors and a series of ænormalÆ production blasts were used as the vibration source. These mounting devices were measured against an in-house procedure (the æstandardÆ) and the relative merits compared. A laboratory investigation was also carried out to look at the physical parameters of the æsoil and their effect on vibration attenuation of the in-house standard method.

Jan 1, 1999

By G J. Lyman, S A. Tittlemier

International regulations exist to manage the concentrations of mycotoxins such as Ochratoxin A (OTA) and deoxynivalenol (DON) in grains and prevent health risks from excessive exposure to OTA and DON. Since the permitted levels of these mycotoxins are very low (existing maximum levels are in the range of 5 ppb for OTA and 1–2 ppm for DON), sampling for these mycotoxins is potentially challenging. Given that the distribution of infected kernels in a consignment of wheat can be highly heterogeneous, detection by current sampling methods is subject to a high variance. Furthermore, the concentrations of mycotoxins in individual kernels vary over orders of magnitude, intensifying the heterogeneity of the bulk grain.In these circumstances, there is much interest in developing sampling plans that inform regulatory agencies, and mitigate the risk of misclassifying grain shipments as compliant or non-compliant within the global grain trade, when correctly implemented.Experimental data from laboratory and field studies describing individual wheat kernel concentrations of OTA and DON were combined with experimental data describing the variance due to the analytical methods used for OTA and DON to calculate the sampling distribution for wheat having various levels of contamination. This work has focused on quantifying the heterogeneity of samples at the point of submission for analysis and within subsequent sample preparation to arrive at total sampling distributions that include uncertainties due to the intrinsic heterogeneity and the analytical uncertainties. The sampling uncertainty that relates to the difference between the primary sample analysis and the true lot analysis is not included as it has been dealt with elsewhere.CITATION:Lyman, G J and Tittlemier, S A, 2017. The sampling characteristics of grains contaminated by mycotoxins, in Proceedings Eighth World Conference on Sampling and Blending , pp 281–294 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2017

Currently in Canada there are 15 major mining companies with a minimum of $1 billion in market capitalization or net private value. This group forms the core of an important sector for Canada. The mining sector had gross revenues of about $35 billion in 1988. This compares to a Canadian GDP of $410 billion in 1988. There are at least three different sub-groups within the mining group, each facing the future with very different prospects for the coming years.

Jan 1, 1989

By R L. Braithwaite

Mesothermal quartz lodes in Paleozoic Greenland Group metasediments of the Reefton area have produced 67 t of gold up to 1951, and recent exploration has identified new gold resources in several deposits, including the largest past producers, Blackwater and Globe Progress. The metasediments consist of alternating sandstone and argillite, metamorphosed to lower greenschist facies and hydrothermally altered near the quartz lodes. We examined and sampled drill core from four prospects, Globe Progress, General Gordon, Merrijigs and Blackwater, to determine the mineralogical and geochemical characteristics of hydrothermal alteration in the sandstone units. The sandstones are feldspathic litharenites averaging Q65, FlO and R25, with detrital grains of quartz, feldspar, rock fragments, muscovite, biotite (mostly altered to chlorite), and trace quantities of graphite, apatite, zircon, tourmaline and titanite. Hydrothermal alteration has developed a secondary mineral assemblage of K-mica (muscovite, sericite and illite), carbonate, chlorite, pyrite, arsenopyrite and limonite. The abundance of secondary chlorite is greater at Blackwater than at the other locations studied. Features in the sediments associated with increasing hydrothermal alteration towards quartz lodes include, the development and increasing intensity of colour bleaching and carbonate spotting, increasing quantities of disseminated pyrite and arsenopyrite, and the appearance and increasing quantity and size of thin carbonate, quartz and sulphide veins. This is accompanied by increasing concentrations of sulphur, arsenic and antimony as shown in assays, and of volatiles (loss on ignition) and iron as seen in XRF analyses. We were unable to identify consistent trends in the behaviour of potassium, sodium, and calcium that are exhibited by similar mesothermal quartz lode deposits inVictoria, Australia.

Jan 1, 1998

By F Hancock

A rainfall simulator was developed to assist with hydrogeomorphic research into the stability of engineered landforms associated with rehabilitated uranium mines in the Top End of Australia. It can be used in rough terrain with slope gradients up to 30o. The rainfall simulator is modular, utilises upward jetting nozzles, has a multiple head arrangement and is capable of delivering rainfall intensities between 60 and 300 mmh-1 over areas up to 1000 m2 and could be easily modified for larger areas. Rainfall uniformity is commonly in excess of 80 per cent and the kinetic energy approaches that of natural rainfall (The modular design utilises an equilateral triangular array of rainfall stands, constructed from galvanised steel water pipes and flexible plastic hoses. Total construction costs are low. The water supply reservoir is mobile and easily constructed. An example of its use at Ranger Uranium Mine, investigating the effect of cover on rainsplash and rainwash dominated processes shows that vegetation cover is likely to reduce the erosion rate by these processes by at least four times below that experienced on bare areas.

Jan 1, 1997

By F Pirajno

"An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation. China’s mineral deposits are the result of metallogenic processes associated with the geodynamic evolution of tectonic plates and eventual amalgamation into their modern configuration. The principal tectonic provinces of China comprise the North China Craton, Yangtze Craton, Cathaysia Craton, Tarim block, Altay-Tianshan-Hinggan orogens (part of the Central Asian Orogenic Bel), Central China orogens, Songpan-Ganze orogen and Alpine-Himalayan fold belts, which are part of the huge Tethysides. These tectonic elements are testimony to a complex geological history spanning more than 3000 million years. This contribution will focus on selected areas of the Altay-Tianshan, the fold belts surrounding the North China Craton and Yangtze Craton and the mineral systems along the Ailaoshan-Red River fault zone. Mineral deposits in these provinces include gold, copper, molybdenum, tin, antimony, nickel, platinum group elements, lead and zinc.CITATION:Pirajno, F, 2015. Metallogeny and related tectonic settings in China , in Proceedings PACRIM 2015 Congress, pp 17–24 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 18, 2015

A detailed study of the capital investment and production cost for copper electrowinning plants shows that significant savings in both can be achieved by increasing the current density. From the economic analysis it is determined that the optimum current density which will result in lowest capital investment and lowest operating cost is between 60 A/sq. ft. and 70 A/sq. ft., or at least three times as high as the Conventionally employed current density. The specific investment, expressed as $/ton-year, is found to be a function of both the current density and plant capacity and has a minimum value at the optimum current density. Empirical equations are developed for the purpose of estimating the capital investment and operating cost for plants of any production capacity operating at any current density.

Jan 1, 1972

Despite technological improvements and better understanding of the hazards, coal dust explosions stilI occur. Experimental explosions in galleries in various countries extend knowledge with the constant aim of providing safer working conditions. The inadvertent ignition of an accumulation of methane is the traditional initiator of the coal dust explosion.There are specific parameters of coal dust explosibility and explosion propagation, including the important volatile matter in the coal, fineness and dispersibility of the dust and its concentration. Accepting that initiation cannot be absolutely prevented, it is necessary to consider explosion suppression. While both limestone dust and water are the chosen explosion suppressants, in practice water has more limitations to its efficacy when related to the degree of explosion violence. These data give rise to the criteria for explosion suppression, differences in favoured mining geometries, and using the same principles, to differences in suppression treatments.

Jan 1, 1988

A numerical method for discriminating between replacement and sedimentary processes is applied to a folded stratiform sulphide occurrence. It is shown that numerical treatment of chemical analyses from a single diamond drill hole allowed a rapid assignment of the ore to the syngenetic sedimentary class and thereby enabled a revision of the evaluation program concerned with consequent reduction in costs.

Jan 1, 1973

By Rose W. J

Geophysical prospecting was first recognized in Australia as an important aid to mining enterprises in 1927, when, on the suggestion of Sir Herbert Gepp, the "Imperial Geophysical Experimental Survey" was organized. The function of this survey was to carry out investigations on the applicability and efficacy of the most important geophysical methods under Australian conditions. The survey was formed under the joint auspices of the British Empire Marketing Board and Australian Commonwealth Government, and the investigations were carried out in Australia under the leadership of Mr. A. Broughton Edge, B.Sc., A.R.S.M., F.G.S., M.Inst.M.M., during the years 1928 and 1929. A description of the work performed, the apparatus used, the principles of the methods, and the results and conclusions of the survey are included in a report published by the Cambridge University Press in 1931.In 1932 Sir Herbert Gepp became interested in some gold mines in Eastern Victoria, in the Cassilis and Bethanga districts, and realizing that the lodes in these areas would be favorabIe for a geophysical examination, he arranged for a series of tests to be carried out. This work was performed by Mr. E. L. Blazey, B.E.E., a former member of the staff of the Imperial Geophysical Experimental, Survey, under the general direction of, and in consultation with, Mr. W. J. Rose, B.M.E.The work was commenced in October, 1932, at Cassilis, Vie., continued at Talgarno, Vie., .and concluded at...

Jan 1, 1933

As in other countries, gold mining inNew Zealand has been cyclic in character. Looking at these cycles may provide insights as to what may occur in the future and that is the basis for this study.   New Zealand has experienced four gold mining cycles. The first began in 1857, peaked in 1866 and terminated in 1890. This cycle was characterised by alluvial gold mining by individuals and small groups. This is referred to as the Labour Led cycle. The second cycle began in 1890 and reached its peak in 1906 and terminated in 1929. This cycle was characterised by the use of dredges in alluvial gold mining and was also the peak of hard rock mining. This cycle is referred to as the Technology Led Cycle. The third cycle peaked in 1940. This cycle was far less significant than the previous cycles, arising out of the depression when the unemployed embarked on small scale alluvial mining. This overprinted the continuing decline that occurred after 1906. This cycle is here referred to as the Depression Overprint Cycle.   The fourth cycle began in 1984 when production began to climb rapidly from a very low base. The growth in production was spurred by rising gold prices in the early 1980s resulting in relatively low grade gold-bearing alluvial ground becoming economic. But in the 1990s, production from the new hardrock mines in Coromandel and Otago has overshadowed alluvial production. This cycle is here referred to as the Price Led cycle.   What are the future prospects for gold in New Zealand? Although there are many factors involved, this will be largely determined by two factors; firstly, continued access to prospective gold-bearing properties, and secondly, the price of gold. Based on these factors, three future industry scenarios have been developed. The first of these is industry collapse, in which access to prospective property is constrained and prices mayor may not weaken. The second is industry consolidation, in which the available ground is accumulated by a small number of large companies who can use economies of scale to weather price fluctuations. The third scenario is industry growth, in which access to prospective ground is constrained in environmentally sensitive areas but is otherwise relatively unconstrained. Efficient companies are allowed to work in a policy and economic framework that allows them to make a major contribution to the economy.   While the industry cannot control these critical factors, a good knowledge of the positive role gold mining could play in the future economy may provide a framework by which the access issue, in particular, may be addressed from a balanced perspective.

Jan 1, 1994

IN December, 1905, a Forwood down-wheeler grinding pan (5 ft dialmter), and similar in design to those in use on the Kalgoorlie goldfields, was installed for experimental work in connection with fine grinding jig tailings.The galena remaining in this product is very finely (closely) mechanically disseminated throughout the blende and gangue, rendering fine crushing imperative for its liberation. A reswne of the milling process in vogue at the old mill will enable the series of operations to be more closely followed. The ore at the South Mine assays, on the average-lead...

Jan 1, 1909

By T Salles, G Duclaux, E R. Ramanaidou

In a continental environment, sediment mobilisation, dispersion and deposition are mainly controlled by mass gravity and streamflow processes. Alluvial sedimentary systems have an important economic value because of their capacity to host mineral resources. In the Hamersley Province, alluvial iron deposits (including the well-known detrital iron deposits and channel iron deposits) play an increasing role on the commodity market. Alluvial deposits exploration is challenging and generally involves geomorphologic and stratigraphic field studies, as well as expensive exploratory surface sampling and drilling. We applied a new surface processes modelling technique to investigate iron rich material, ie the erosion product of bedded iron formations -dispersion in the Hamersley Province. LECODE is a 3D-parallel surface processes forward modelling code designed to compute surface flow and solve erosion, transport and sedimentation on the geological time scale. The code offers new quantitative ways to better understand how sedimentary deposits develop in intra-continental and channel environments. Here we show that our integrated forward model is capable of opening a window to the construction of sedimentary architectures, including facies distribution, deposit thickness and development of heterogeneities such as mineral traps over the modelled domain. The model results represent 1 Ma of surface evolution and are validated through comparison to published paleovalleys map and known occurrences of iron ore deposits. This numerical modelling approach allows for the first time to track alluvial materials from source to sink through time, test existing geological models and faithfully reproduce the first order distribution of alluvial iron deposits in an area of interest. This work strongly suggests the presence of iron rich alluvial deposits reserves under cover, in unexplored detrital fans in the Fortescue Valley. This method, potentially coupled with sediment geochemistry and basin analyses studies, has the potential to maximise alluvial iron deposits exploration success, while reducing exploration cost and associated environmental impact.CITATION:Duclaux, G, Salles, T and Ramanaidou, E R, 2013. Alluvial iron deposits exploration using surface processes modelling - a case study in the Hamersley Province (Western Australia), in Proceedings Iron Ore 2013 , pp 75-80 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 12, 2013

By A Kamkar-Rouhani

The paper describes a mineral potential mapping of gold and other base metals in Mahneshan area, Iran, using geographical information system (GIS), in which, the method of weights of evidence is used to combine spatial data obtained from different sources to make prediction for mineral potential. This is a quantitative tool for mineral resource mapping that can be used to delineate and predict favorable areas for further exploration by using the characteristics of known and similar mineral deposits. In accord with the descriptive model for gold and other base metal deposits, the spatial distribution of 20 known mineral occurrences was used. In addition, digital evidential maps were used in this study. The maps include maps of lithological units, faults and first derivative of total aeromagnetic data, remotely-sensing data of alteration and also geochemical evidential maps produced on the basis of the results of chemical analyses of samples taken from the stream sediments in the area, and analysed for Cu, Pb, Zn, Sb, As, Ag, Au, Ba and Hg elements. The binary maps were produced and then combined with the model of weights of evidence using 20 known mineral occurrences to obtain a final map of the favourable areas for further exploration of gold and other base metals in the study area. The final map is a predictive GIS model of the mineral deposits in the area. An interesting matter about the final predictive GIS model is that the faults are mainly located in favorable areas which possesses the most probability of mineralisation. Therefore, the faults in these areas have priority for further exploration of gold and others base metals.

Jan 1, 2005

The history of the industry which recovers rutile and zircon from the heavy mineral beach sand deposits of Eastern Australia began with the initial discovery of zircon in 1895. Whereas a large number of small companies operated during the rutile boom of 1955-57, the industry is now controlled by a few large groups.Mining is mainly by suction dredging. Metallurgical practice is a two-stage process in which a bulk concentrate of heavy minerals, recovered by gravity methods, is separated into its constituent minerals by processes based mainly on surface, electrical, and magnetic properties.Various separating devices using these principles have been developed in the industry and combined in various ways in the operating plants.There is scope for future metallurgical developments.INTRODUCTIONThe existence of deposits of heavy minerals ("black sands") on the northern coast of New South Wales has been known for at least 90 years. The earliest metallurgical operations aimed at the recovery of gold, platinum, tin and monazite. Mainly because of the low grade of these deposits with respect to these minerals, but also due to metallurgical difficulties, such operations were abandoned by about 1895 (Whitworth, 1959). The presence of zircon was recorded quite early (Carne, 1895) but Raggatt (1925) appears to have been the first to report the presence of rutile.The economic exploitation of the deposits was initiated in 1928 when D. H. Newland, State Geologist of New York, made an examination on behalf of The Titanium Alloy Manufacturing Company of America. Developments were then delayed by the world-wide depression, and the first commercial separation of the heavy minerals was made at Byron Bay in 1934 by Zircon Rutile Ltd. using a froth...

Jan 1, 1963