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Good morning and thanks for the chance to talk to you. It's really pleasing to see so many industry representatives here I want to spend a few minutes talking about issues relating to your industry. At the end of today I would like to leave you with three strong messages from government. The first is that this government supports environmentally responsible mining and the endeavours of the mining industry. The second is that explorers and developers are wanted and welcomed in New Zealand. And the last is that it is up to the industry to keep the public properly informed about how your industry and to constantly work on improving your public image. The mining industry is a high-tech industry which fits snugly with our concept of a growing knowledge-based economy. It has particular value for regional development, the gold mining industry alone provides more than 4,000 jobs û mostly outside of the main cities. The industrial minerals industry is twice as large as that. As well as those people directly employed by the industry there are greater downstream effects for the community. One example from the broader extraction industry of this is of the local pie shop down the road from one of Taranaki's petroleum industry locations. The shop sells over $4,000 worth of pies a week to workers in the industry. That's just one example of the positive benefits the industry brings to its local community and is the sort of real positive benefit you need to be telling people about  

Jan 1, 2000

Tonnage and grade are the principal reported components of mineral resource estimates but tonnage is a derivative of two more fundamental estimates; volume and bulk density. Typically, most of the effort in a resource estimation study is directed towards grade and volume, yet poor application of bulk density data to resource models can result in significant biases. The impact on tonnage estimates is easily recognised but poor density estimates may also introduce subtle biases into the grade estimates. Methods for measuring bulk density have been discussed previously. This paper focuses on the manipulation of bulk density data and the extension of bulk density from essentially point measurements to block estimates within resource models. Bulk density is a continuous, geologically controlled, spatial variable and should be treated as such. Issues such as combining data from multiple sources, sample support and the interdependence of bulk density and grade estimates must be resolved. The statistical and geostatistical techniques used for grade estimation are, under the right circumstances, equally applicable to bulk density. The importance of bulk density needs to be recognised. With robust raw data and correct estimation procedures, better estimates of bulk density can be obtained and both local and global tonnage and grade estimates can be improved.

Jan 1, 2000

By Conochie DS

SIROSMELT is a successful new pyrometallurgi- cal furnace system using a top-entry lance which can be submerged in both slag and matte. The lance is of simple construction, and is cooled by process air. Pilot plant work commenced in the CSIRO Division of Chemical Engineering in 1972 using a 50 kg batch reactor. This paper traces the development of the technology through various slag cleaning and smelting processes up to a scale of 5 tonnes per hour continuous feed. Strong co- operation between CSIRO and the Australian smelting industry has contributed greatly to the success of SIROSMELT.

Jan 1, 1984

By J Ramezani, K Faure, N Mortimer

Western New Zealand can be regarded as a rifted continuation of eastern Australia. Detailed studies of units previously considered to have trans-Tasman correlations are being undertaken within the FRST Programme Mineral Wealth of NZ and its EEZ to test specific connections, and thus add to the exploration framework of NZ. Correlation of two major episodes of granitic magmatism are currently being investigated. These represent the oldest (mid Paleozoic) and youngest (Early Cretaceous) magmatic events that conjoined Australia and New Zealand are believed to have in common.

Jan 1, 2007

With the recent wider introduction of friction hoists of the Koepe type. for winding from depths of more than 3000 feet it has been found that failure by fatigue is the most common form of rope deterioration. Large numbers of wire breaks occur near the centre of the rope cross-section and it is difficult to detect these with certainty using the preferred d.c. magnetic test. For best results with conventional search coils their dimen- sions should be related to the typical wire break field pattern surrounding the longitudionally magnetised rope. The field of a broken wire was experimentally determined, using a Polish type MD6 Defectograph wire rope testing magnet and a short prepared length of rope with a movable simulated broken wire. The external field distortion perpendicular to the rope was measured by means of a gaussmeter and Hall probe. The advantages of this method are that terrestial magnetism and inherent rope "noise" have no effect on the results.

Jan 1, 1971

By S Hu, P Ni, H Xu, P Chen

Indosinian (T) orogeny amalgamated the Mongolia-Xingan fold zone, the North China continent, the Yangtzi platform and the SE China fold zone into a unified continent. The early to middle Yanshanian (J-K1) orogeny created a Cordilleran type active continental margin in East Asia, reactivated the consolidated East China continent, and generated a large amount of granitoids, calc-alkaline volcanics and W, Sn, Mo, Cu, Au, and U ore deposits. The late Yanshanian (K2) orogeny began a transition to the western Pacific type continental margin. A tensional environment led to the development of peralkaline magmatism and tne formation of continental basins with red beds. The Himalayan (Tr-Q) orogeny was characterised by a backarc spreading and rifting regime. The dominant magmatism was continental basaltic.

Jan 1, 1995

By M R. Stevens

An approach of geological mapping and descriptive criteria has been used to identify hydrothermal eruption breccias, named the Onemana Breccia. These in part mantle a gold bearing fossil hydrothermal system located on the eastern side of the Coromandel Peninsula, New Zealand. Whilst eruption breccias are documented from active and recent geothermal centres within the Taupo Volcanic Zone and in Northland their recognition at Onemana is the first confirmed discovery for this lithotype within ancient hydrothermal systems of the Coromandel Volcanic Zone. At Onemana the widespread occurrence of silicification, sinters, volcanic lake sediments, eruption breccias and advanced argillic alteration allows classic hot spring epithermal modelling. The geological setting, distribution, lithological characteristics, hydrothermal alteration and trace element geochemistry of the Onemana eruption breccias are described. These breccias are closely comparable with hydrothermal eruption deposits elsewhere, particularly those in active ore forming hydrothermal systems. Consideration is given specifically to the role of the Onemana Breccia in an exploration strategy for discovering epithermal gold-silver deposits.

Jan 1, 1991

By Johnson D. P, Beamish B. B

The northern Bowen Basin has a very large resource of coalseam methane gas-in-place - 136 TCF(7ohnson and White, 1988). The gas is pipeline quality, being 98-99 per cent methane with traces of carbon dioxide and higher hydrocarbons. The largest resource of natural gas within the coalseams of the northern Bowen Basin is contained in the Moranbah Coal Measures (75 per cent). The next most important resource is in the combined upper Fort Cooper (16 per cent) and Rangal (nine per cent) Coal Measures. The far northern parts of the basin have low gas contents due to the combined effects of limited extent of the coal measures, shallow depth and low rank. Reserves per well are more than double that of the best coalseam methane wells in any basin in the United States. In some areas of the Moranbah Coal Measures, the gas-in-place estimates exceed 225 million cubic metres per well (80-acre spacing). A distinction is made between resource base, as determined from this basin assessment, and the deliverability potential. Parameters used to estimate gas-in-place (coal area, thickness, density, rank and depth) can be adequately extrapolated from areas of high- to low- data density. Parameters affecting methane production (permeability, gas depletion factor and critical desorption pressure) cannot be generalised. Exploration and development programs must rapidly develop a predictive capability for these factors, on a local scale, through geological modelling and confirmation drilling.

Jan 1, 1991

By B McCreath

Industrial process water for the Commodore Coal Mine and the adjoining Millmerran Power Station is provided by pumping secondary treated sewage effluent 100 km from the Wetalla Sewage Treatment Plant near Toowoomba. (A separate source is used for potable water.) The effluent is not of sufficient quality for discharge to a watercourse, but it is suitable, with further treatment, for the mine and power station. In designing and constructing the pipeline, special emphasis was placed on preventing accidental spills or planned releases to the environment. The pipeline and associated works can transfer 1000 ML/annum for reuse in the coal mine and power station.

Jan 1, 2003

Building the Unified Comminution Model The Unified Comminution Model (UCM) was formulated with the vision of bringing all comminution models onto a common base. The structure of the model relies on knowledge of the mechanical environment in the comminution devices to predict the modes and rates of collision in a device. A detailed understanding of the breakage modes and an ability to correctly test these modes for the ores in question is then required to feed into the UCM. A model structure has been developed that has the capability of dealing with multiple modes of breakage, such as low energy impact surface damage, chipping, sliding abrasion, cumulative impact body breakage and the transition of rock between modes. A critical review is presented on the shortcomings and limitations of utilising the discrete element method (DEM) to provide the mechanical environments. The assumptions and applicability of utilising DEM in milling models are presented and proposed routes to building a realistic mechanistic model are proposed. Based on this more realistic measures of collision energy have been derived from the DEM simulations, which better mimic the real breakage tests. Generic forms of the collision energy distributions have been observed and developed into functional forms for use in the simulation environment. The method of application of this model to a pilot SAG mill is presented.

Sep 13, 2010

The mining industry in Australia frequently uses the services of specialist engineering and managing contractors and consultants for a majority of the work required for project development, from feasibility studies to project commissioning. The project owner's prime objectives are to achieve predictability and competitive advantage for their project. As the majority of this work will be carried out by contractors, the effective evaluation, selection and management of these contractors in the most appropriate forms of contracts is an essential ingredient to project success. The first stage to project development should be for the owner to examine its own resources to establish the role that it will fill and thereby identify the role and scope of contractors' involvement. Once the owner has developed this work plan, the selection of contractors and consultants should be structured to ensure that the owner acquires the appropriate expertise and experience to achieve its project objectives. The sequence of selection procedures is: 1. Pre-qualification of prospective contractors according to the owner's adopted criteria, through the use of a pre-qualification questionnaire. 2. Evaluation by the owner tender board according to predetermined mandatory criteria. 3. Preparation of tender documents for submission to qualified contractors. 4. Evaluation of tender submissions by the owner tender board using a pre-determined, weighted matrix of technical and commercial criteria. 5. Final selection and contract negotiation.

Jan 1, 1990

W. Johnson (Consultant, Adelaide) : Is there any mineralogical evidence of temperature of formation of the amphiboles and other minerals present in the crocidolite veins and country rocks7.N. A. Trueman: I am not aware of any definite evidence of the temperature of formation of these minerals, but am of the opinion that high temperatures would not be present during crystallization.No evidence from the qUl'trtz, magnetite and hematite of formation temperatures is indicated and, as the carbonate is later than the other minerals it does not supply any data either.According to Miyashiro and other workers who have studied the composition and stability of the glaucophaneriebeckite series, minerals of riebeckite composition are stable over a wide range of P, T conditions. Recent work by W. G. Ernst, of the University of California, indicate that, in the presence of an Fe203/Fe304 buffer, riebeckite and crocidolite are more likely to form at low temperatures. The occurrence of riebeckite-crocidolite as authigenic minerals has been reported from several localities.Dr. MacLeod (Geol. Surv. of W. A.): Recent regional mapping by the Geological Survey of Western Australia has revealed a total thickness of at least 30,000 ft for the Proterozoic sediments in the Hamersley Basin. In this succession the asbestos-bearing beds of the Brockman Iron Formation at Wittenoom are overlain by some 20,000 ft of younger sediments and volcanics. With such a thickness of superincumbent material, it seems perfectly valid to involve

Jan 1, 1963

By Mwaba CC

Ok Tedi Mining Ltd has been using flotation for the production of copper/gold concentrates from a complex copper sulphide ore for several years. During this period, much effort has been devoted to metall- urgical treatment of the ore. This paper examines some of the mineralogical aspects of the sulphide minerals in the ore using the electron microprobe analyser. Results have revealed the complexity of the copper sulphide minerals and in particular, chalcocite. Analysis of both plant and laboratory flotation products has provided further insight into the effects of mineralogy on the flotation of copper and iron sulphides. A significant observation is that some of the pyrite minerals apparently exhibit natural floatability. The implications of the mineralogical characteristics of the sulphide minerals on the flotation of the ore are also discussed.

Jan 1, 1991

By M Pyle, R Ch, G Lane, ramhan

Data is the most valuable commodity in the information age. The use of data enables productivity, opportunity, and safety in various sectors and industries. In the late 1950s, Alan Turing coined the term artificial intelligence (AI) to describe the ability of computing machines to think and behave like humans through simplified reasoning and logic (Turing, 1950). This concept of mimicking human behaviour is the building block of machine learning algorithms used in most AI software. The ‘learning’ aspect in machine learning requires data, that is, information on the environment or the objective, to be modelled or predicted using AI. An AI-enabled system aims to predict the unknown faster and intuitively. Intuition in software algorithms can be described as probabilistic, learned through the data that the AI system is trained on; indeed, the AI software cannot predict the future, but it can provide the likelihood of an event/action occurring, thereby enabling decisions or responses to prevent it or take action. Just as various industries have adopted AI as the tool of choice to seek new opportunities (examples: medical research, self-driving cars, financial modelling), the mining industry, too, has been receptive to embracing AI for problem-solving and maximising the value of its business.

Sep 1, 2024

By M W. A Asad, E Topal, D S. S Sandanayake

Underground mine planning requires an optimal stope layout as a prerequisite for the definition of an optimal production schedule. The procedure to generate an optimal stope layout considers an orebody model and economic parameters as inputs. It evaluates all possible combinations of mining blocks and creates a set of stopes by satisfying the physical mining and geotechnical constraints. Thus, the procedure is computationally complex, and generating a solution to the problem is a challenge. This paper presents an implementation of a new heuristic algorithm that solves the stope layout problem. In two case studies, the algorithm achieves 11.2 per cent and 22.5 per cent superior solutions to the industrially available maximum value neighbourhood approach.CITATION:Sandanayake, D S S, Topal, E and Asad, M W A, 2014. Implementing a new heuristic approach to the underground mine stope layout problem, in Proceedings Orebody Modelling and Strategic Mine Planning Symposium 2014 , pp 243–248 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 24, 2014

By Jingcai Xu, Singming Gou

A sound mathematical model is an important step to predict spontaneous combustion probability so that measures against coal self-heating can be adopted in time and at comparatively low-cost. This paper analyses main factors in coal spontaneous

Jan 1, 1998

Although these subterranean cavities are common to the Broken Hill big lode, yet the Broken Hill Proprietary is the most prolific in their occurrence, loud they have been found of various dimensions almost from the surface down to the lowest levels yet attained in that mine. Many of these vugbs have contined valuable silver, copper and lead deposits, and some have been remarkable for the beautiful forms of crystallization pendant from the roofs and walls, and collected on the floors. The question arises, How are these caverns and fissures in the ore body formed? There are numerous theories more or less feasible, but that the causes are variant is demonstrated beyond doubt. That water in its passage leaving channels, is one ofthe chief factors for their production is assured, and their presence is likewise due to the shrinkage and dropping of the earth from varions causes, to the deposition of material forming ledges overhanging, and thus leaving spaces below, and also to chemical erosion and electrical action both of which latter are constantly at work in reconstructing, segregating and dissolving tlie mineral and metallic constituents of all ore bodies.One of the most remarkable vughs yet discovered in the big mine was that opened up about three months bitek in the' heart of the ironstone body on Block 11, and located about 40 feet below the 100 feet level of Weatherley's stopes, but now destroyed in the progress of work. Probably it was caused by chemical action, the eating out, so to speak, of a soft and soluble portion of the manganic iron, leaving a,hollow about 15 feet long, with a width and height, of say, 6 feet, carpeted with beautiful zinc with a modicum of limeincrustations, apparently produced by the percolation from around the carbonate waters holding these minerals in solution. This cavern was divided into, what might be termed, a double chamber, by big boulders of manganic iron, also coated with an aggregation of small crystals of zinc and lime although the actual proportion of the latter was not determined.

By Fookes R. A, Bunch K, Gravitis V. L, Watt J. S

The combustible volatile matter in coal mine roadway dusts (CVM) has been determined using x-ray backscatter techniques. The correlation between x-ray and chemical techniques is reasonably good for the 92 samples from collieries on the Bulli seam, and the maximum error expected at the maximum level of 11· 5 weight per cent CVM permitted in the N.S.W. Coal Mines Regulation Act, 1912, as amended, is about ± 2·5 weight per cent. This x-ray technique can be used only when the combustible volatile content of the coal matter (cvm) varies within a limited range, and a separate calibration is required for each coal seam.Portable equipment based on a radioisotope x-ray source ahd digital ratemeter makes possible simple and rapid analysis, and with adaptation to use in coal mines should lead to much more comprehensive testing- ofroadways and hence improved overall prevention of coal dust explosions.

Jan 1, 1977

Separation of Iron Particles from Banded Haematite Quartzite (BHQ) Ore by Selective Magnetic Coating The separation of fine iron particles from banded hematite quartzite (BHQ) has been studied using selective magnetic coating. The BHQ ore assays as 38.9 per cent Fe, 42.5 per cent SiO2 and 1.0 per cent Al2O3. Mineralogically, the ore contains hematite and quartz as the major mineral phases where as goethite and magnetite is present in minor entities. Natural magnetite of very fine size and oleate-magnetite in colloidal form, prepared synthetically in the laboratory are used as the coating material on the surface of hematite particles. The selective coatings of oleate-magnetite on BHQ surfaces followed by magnetic separation studies have indicated that, it is possible to achieve 62.3 per cent Fe with 8.5 per cent SiO2 at 85.4 per cent iron recovery. The recovery of iron values is found to be superior in comparison to the conventional magnetic separation techniques. The selectivity of coating for enhancing the magnetic response of iron particles is achieved by controlling the surface properties of the particle via electrokinetic potential adjustment by controling pH and addition of oleate-magnetite. In the separation process, the effects of pH, magnetic intensity and addition of oleate-magnetite are studied to achieve the maximum grade and recovery of iron values. The optimum separation is observed at pH of 7.5, oleate-magnetite concentration of 0.25 ml/g of BHQ ore and a magnetic intensity of around 0.8 Tesla. The X-ray diffraction (XRD), Infra-red spectroscopy (IR) and UV-visible spectroscopic studies strongly suggest preferential coating of magnetite on hematite surfaces. Scanning electron microscopy (SEM) studies have brought out the semi-quantitative features of BHQ ore. The recovery of iron values from a lean grade ore such as BHQ is carried out looking into the future needs of this ore in India for iron and steel making.

Sep 13, 2010

By T Rock

This paper looks at recent advances in the United Kingdom (UK) tunnelling industry with particular reference to the A3 Hindhead Project. A 1.8 km long twin bore tunnel is the centrepiece of the A3 Hindhead scheme, which commenced construction in 2007 and is being delivered under a UK Highways Agency early contractor involvement (ECI) contract. The proposed construction methodology is progressive mechanical excavation of a horseshoe-shaped tunnel with shotcrete installed close behind the face using robotic spraying equipment. The tunnelling medium is a æsoft rockÆ sandstone for which there was little previous tunnelling experience, requiring extensive geotechnical investigations and an innovative approach to lining design. A 240 m long section though sandy material utilising a steel pipe umbrella is also required. This paper describes the development of the tunnel planning and design including the most recent developments in UK road tunnels. The innovative approach to the design of the following is discussed:the æpermanentÆ primary lining,an observational technique allowing optimisation of the steel pipe umbrella design,a plain concrete secondary lining designed for resistance to a hydrocarbon fire, anda spray-applied membrane.

Jan 1, 2008