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By P G. Rutherford, A W. McOnie

A volcanic sequence is described from the Golden Cross Mine, Waihi, New Zealand. The sequence includes seven lithostratigraphic units comprising flow and pyroclastic units of Coromandel Group andesite and dacite and overlying Whitianga Group dacite and rhyolite which is intruded by the Golden Cross dacite porphyry and rhyolite dykes. The sequence is mineralised and is unconformably overlain by two post-mineral units, the lacustrine Waitekauri beds and Omahine Subgroup andesite.   Detailed structural analysis of mine data has identified four deformational events (D 1-D4) and related these to the gold-silver mineralising events. Faulting was coeval with the mineralization and directly controlled the development, localisation, style and geometry of the ore shoots. Mineralization developed in competent lithologies where dilation occurred during faulting. The Empire Fault is the master shear which controlled fluid flow. Mineralised veining developed in response to tectonic pulses occurring at slightly different stages as represented by the underground Empire vein complex and the open pit vein array. The mineralising events culminated with the deposition of barren calcite veins. Post-mineral movement along the Western Boundary fault appears to have offset the orebody.

Jan 1, 1995

Infrastructure is defined as all those parts of a mining development which are not directly concerned with mining and mineral processing. Infrastructure is of significant and growing importance in the overall develop- ment of mines, and the costs could be critical in determining the viability of a project. Prior to_project authorisation, feasibility studies are required, often in considerable detail, to determine costs with adequate reliability. It is necessary that the Engineer should be adequately briefed for carrying out these studies and that good liaison and communication with the Owner be maintained. Methods, costs, order of accuracy, and some special requirements of these studies are discussed. After project authorisation, rapid im- plementation of the proposals is generally desired. A suggested organisation and method for this implementation is presented and dis- cussed. Comments on fees, and particular points in the relationship between Owner and Consulting Engineer are given. Particular reference is made to differences in conditions compared with public works projects. Realistic attitudes of mind towards environmental matters, industrial relations, and contractual relationships are advocated.

Jan 1, 1974

Mines in the future deliver a paradigm shift in the way mining, material handling and processing are performed, unlocking significant value through production efficiency, flexibility and lower costs and enabling substantial safety and environmental benefits (V Schweikart). Mines in the future are highly productive, with low production costs and are significantly safer. They operate with a skeleton crew and use intelligent systems that fuse information from field instrumentation and other sources to generate the most efficient operating environment. Automated systems are seamlessly integrated across the mine and across the corporate enterprise. Geological models, long-term and short-term plans create optimised production schedules, suitably generated by the mine simulator. Production schedules are shared with the operations management system for deployment mainly by remotely operated and autonomous equipment. As the schedule is implemented, information is collected and shared with various plans, schedules, models and optimisation programs. This production environment is managed in real time from a æCentral Operations CentreÆ and it is visible across the business providing fast and accurate information about productivity, machine condition and environmental conditions. Central Operations Centres also house teams of subject matter experts that monitor and manage the mines and are able to communicate directly with the skeleton crew in the field. Constraints across the production line are displayed and managed appropriately from this location to maximise throughput. Maintenance is interactive and predictive. Reliability specialists in Central Operations Centres monitor the status of machinery and equipment and adjust maintenance plans and strategies to suit. Mining businesses rely heavily on knowledge workers û people with considerable knowledge and learning û and by manual workers. This new knowledge workforce is a team of associates rather than of bosses and subordinates. Field experts become leaders with tremendous autonomy regarding their work. The former line hierarchy becomes a support structure, intervening only in extreme emergencies; instead of giving orders, they are now removing barriers, expediting resources, conducting studies and acting as consultants.

Jan 1, 2009

Nickel-bearing ores in North-east Dundas have been described by A. McIntosh Reid1 as occurring at the margins of narrow dykes of gabbro, norite, peridodite and pyroxenite, which are intrusive into the Dundas series of slates, quartzites and breccias. They occur chiefly in the neighbourhood of the Five Mile, near Zeehan, as small, narrow ore-bodies which are mostly less than 100 ft. in length.The ores are massive sulphides containing pyrrhotite, chalcopyrite, pyrite and the nickel sulphide, pentlabdite.A less common nickel-bearing mineral, gersdorffite, has been recently found in an adit, which is marked on Reid's geological plan of Dundas as the Hecla mine, 30 chains south of the crossing of the North-east Dundas tramway, over the Great Northern Creek, and at an, elevation of about 350 ft. above the tramway. The occurrence is in a lode traversing the Dundas slates and quartzites, and is situated, according to Reid's plan, about 20 chains beyond the northern extremity of a narrow basic dyke which is continuous for a distance of two miles in a south-westerly direction.The mine eonsists of a prospecting adit following the course of a lode for about 275 ft. in a direction a little west of south. The low values of the lode are indicated by a bulk sample from a shallow winze about 100 ft. from the entrance which is reported by Reid to contain:

Jan 1, 1935

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

The need for the hydraulic transportation of coal in the New South Wales coal industry, both from the coal face to the surface and from the coal mine to the consumer or the port for export, is explained. Details of research projects currently in progress and involving the hydraulic transportation of New South Wales coals are given together with information on the hydraulic transportation of coal in the United States of America. The potential of hydraulic transportation as a viable alternative to the proposed expansion and upgrading of the New South Wales railway system to meet the projected New South Wales coal production to the year 2000 is described.

Jan 1, 1980

Electro-Flotation Research on Fine Cassiterite

Sep 13, 2010

The Performance of Benzyl Arsonic Acid as a Collector in the Flotation of Wolframite and Cassiterite Slime

Sep 13, 2010

Confirmation of significant mineable reserves of high grade silver ore at Elura Mine has led to the development of a high cost, high recovery mining system. At the contact of oxidised and sulphide ores lies a supergene zone of enrichment which has provided a contrast, not formerly imagined, to Elura's primary development and stoping operations. Because of the soft nature of the ore, intense ground support practice has been combined with a panel cut and fill continuous mining system to extract a reserve of small, but most valuable Proportions.

Jan 1, 1988

By A Bagis

Road tunnels are an accepted and effective transportation solution in urban areas to mitigate increasing traffic congestion and facilitate improved urban connectivity in a cost effective manner while meeting societal goals to reduce the impact of construction. In designing a tunnel system, there is a requirement to achieve an acceptable level of in-tunnel air quality, as well as meeting ambient air quality goals. In Australia, there is also a requirement for zero portal emissions which means that all pollutants must be emitted to the atmosphere via a ventilation stack.Traditionally, effective pollutant dispersion has been achieved by constructing tall ventilation stacks which disperse pollutants into the atmosphere at a high level. The dominant variable parameters in the effectiveness of the dispersion under the ventilation engineers control are the efflux velocity, the height of the ventilation outlet and the concentration of pollutants at the point of discharge. During off-peak operations the required ventilation exhaust rate can be reduced due to the decrease in traffic. This can lead to a drop in the efflux velocity from the stack and therefore the effectiveness of the dispersion. This potentially drives the need for a higher outlet, or an increased exhaust rate to achieve a higher efflux velocity with consequent effects on energy consumption.The paper proposes a method of varying the cross-sectional area of the ventilation stack with the use of motorised control dampers, thereby maintaining a sufficiently high efflux velocity throughout the 24 hour period independent of traffic conditions. This allows the use of a potentially shorter ventilation stack.

Mar 8, 2011

By R Harding, T Hunt

For the past 120 years, Portland cement manufacture has been undertaken on the shores of the Whangarei Harbour in northern New Zealand. Through a serendipitous conjunction of geo-chemistry, the argillaceous marl found on Limestone Island in the harbour and Tikorangi Hill provides a perfect mix of the various elements required for strong and durable cement. Golden Bay Cement, and its predecessors, have been the guardians and managers of the use of these minerals. As the demands of the concrete industry have increased, so have the needs of the manufacturing process. Careful mapping of the resource at both Portland and Wilsonville Quarries has been undertaken. This has allowed the Company to change the Quarry operation from a purely volume basis to one of selection and blending of constituent minerals. Within the manufacturing process, change has also been introduced. Analytical techniques, using x-ray fluorescence spectrometry, microscopy and the application of modem data collation, has allowed fine tuning of the process. The Company now produces an increasing diverse range of products for both the domestic New Zealand market and exports to various South Pacific countries. This paper discusses the processing of limestone and æcement rockÆ into cement clinker, an intermediate synthetic mineral ground into cement. It examines control and blending regimes, and some methods used in determining process efficiency. An important technique ærediscoveredÆ has been the application of microscopy to clinker.  Examination of the major silicate minerals enables interpretation of the kiln processing and feedback to process operators. It also enables a prediction of indicated performance when ground into cement. Examples this paper give an insight into the use of minerals from Northland in some of the more important construction projects in modem New Zealand.

Jan 1, 1999

The Research Centres Program initiated by the Federal Government and supported by the mining industry has had a major impact on geoscience research and education during the past five years. Eight major university based-Geoscience Research Centres are currently supported by the Government, including four Key Centres of Teaching and Research and a further four Cooperative Research Centres (CRCs). The Research Centres Program has led to a concentration of high quality research and teaching in areas of demand and strategic importance creating strong university - industry linkages and a source of well trained and motivated graduates. Over the last decade Australia's reputation as a leader in mineral exploration and ore deposit research has grown substantially, in part because of the development of the Research Centres Program, and to increased collaboration and interaction between research groups and exploration geoscientists across the industry. During a period when ore deposit research activity has been decreasing in other countries (eg USA, Canada, Japan and most European countries), equivalent research activities in Australia have been increasing, within a well co-ordinated national framework. The future challenge for universities and the mining industry will be to maintain the momentum of the successful research centres in order for the centres to become self-funding over a six- to nine-year period.

Jan 1, 1996

By using knowledge-based technology to create a Virtual Mining Enterprise and integrating it with existing technical and financial computer systems, a gold mining company has been able to reduce the time taken to produce a mine plan from 14 weeks to less than one week. Typically, the mine planning process requires circulating and managing large amounts of information. Even with the use of computers in todayÆs business, this is often still a manual process involving file transfers and individualised spreadsheets. Mine planning also involves understanding and managing large quantities of complex and interrelated variables. Added to this is the ever changing dynamics and constraints associated with the business of mining. These issues not only hamper the planning process but also question the validity and usefulness of the mine plans being generated. By integrating the information and knowledge of the numerous departments involved in mine planning into one core Knowledge Base - so called æone version of the truthÆ, - mining companies are able to overcome these pitfalls experienced in traditional planning methods. Once set up, the Knowledge Base creates and runs a virtual mining enterprise with which to visualise and test various scenarios of mining, business and logistical activities. The final output is an optimised enterprise-wide plan with clear and detailed instructions for each of the divisions of the company.

Jan 1, 2000

By J Parr, P Ashworth, S Johns, C Yeats, A Littleboy

The ocean floor is increasingly being discussed in terms of its resource potential. New discoveries, improved knowledge and access to unexplored areas of the deep sea and continental shelf are some factors contributing to a renewed interest in the seafloor exploration and mining industry. The industry has been referred to as the ænext minerals frontierÆ. To date, much of the research has focused on proving economic and technical viability of the industry, with environmental issues addressed locally. However, there is limited research internationally, and none known in Australia that considers the social viability of the industry, addressing issues such as regulatory contexts, international precedence and public acceptability. Does the nascent seafloor exploration and mining industry have a social license to operate? Does it have support amongst the wider community? If not, why not? The Wealth from Oceans National Research Flagship explored these questions by scoping the social issues that would surround an expansion. Two desktop studies provide insight into the current level of activity in seafloor exploration and mining, recent developments and the regulatory regimes on which the industry is based. One study focused on the situation in Australia, while the other was internationally focused. A series of workshops were held with key stakeholders from government agencies, industry and other interested parties, such as environmental groups and the fisheries industry. These workshops identified and explored the different stakeholdersÆ perceptions of the benefits, concerns, opportunities and key questions associated with an expansion of the seafloor mining industry. The desktop studies revealed that Australia is one of only a few countries with legislation specific to seafloor exploration and mining. Nevertheless, barriers to licence approval exist because of lack of precedent in applying this legislation. Consequently, the decision process can be vulnerable to political issues and subjective judgements. The outcomes from the stakeholder workshops suggest this inconsistency may be influenced by the high levels of concern and uncertainty over environmental impacts. Uncertainty over environmental impacts can influence the acceptability of an environmental impact assessment (EIA) and also mean the perception of risk is variable. Overall, this research suggests that the future of the seafloor exploration and mining industry will be highly dependent on AustraliaÆs ability to:improve the knowledge-base underpinning the regulatory regime,generate open and transparent communications between stakeholders, andimprove the understanding of policy and regulatory processes.

Jan 1, 2008

By Sutherland R. A, Rawling K. R

The Nanisivik Mine is located 750 km north of the Arctic Circle at the north end of Baffin Island in the Canadian High Arctic, and has been in production since 1976. The paper describes the regional and local geology and the current mining and mineral processing operations, including recent innovations in each area. The Nanisivik zinc-lead deposits comprise Mississippi Valley type sulphides in a block-faulted sediment sequence of Proterozoic age. The deposits formed in two mineralizing stages by replacement of the carbonate host rock. Exploration techniques adapted to the permafrost environment include high frequency EM and ground probing radar. Core drilling is done with calcium chloride brine but trials with heated flushing water indicate potential for cost reduction. The predominant mining method at Nanisivik is room and pillar. Cut and fill is used in some satellites to the main zone. Due to the permafrost, dry drilling is employed in the underground mining. The permafrost enhances ground stability, permitting large underground openings and, as a result, the use of relatively large scale mining equipment. For power conservation, a remote control system for the ventilation fans has reduced mine power costs. The milling of the simple coarse-grained ore in an arctic environment requires special techniques in the design and operation of the plant for materials handling, utilisation of waste heat, reagent selection and tailings disposal. Regulated heavy metal contents in effluents discharged to the sensitive environment are achieved by natural processes. A recent change from sub-aqueous disposal of tailings to beach type deposition within a cell in the tailings area is reviewed. Planning closure of the property presents special problems and an opportunity for innovative techniques. Approximately 25 per cent of the employees at Nanisivik are drawn from the Inuit population of the Canadian Arctic. As the first permanent industrial activity in the High Arctic some innovative approaches to employee relations were required which have resulted in a very stable, culturally mixed community in a remote location.

Jan 1, 1993

By Sullivan BJK

The 1100 orebody is a massive copper sul- phide orebody which contains a major portion of the Isa Mine copper ore reserves of 130 million tonnes at 3.2%. The underground mining of a deposit as large as the 1100 orebody is technologically a complex operation as extraction strategies have to be evaluated with reference to 1. rock mechanics considerations, 2. safety and environmental standards, 3. production and operating require- ments and 4. metal recovery and costs. The mining philosophy in the orebody has undergone considerable change over the past five years as a result of experience and improved technology. At this stage, primary stopes are extracted by high rise sublevel open stoping and pillars by slot and mass blast drawn either under rock fill or as an open Stope.

Jan 1, 1978

The care necessary to ensure a reliable estimate of average value from the individual values of a series of bore holes sunk in any alluvial deposit containing coarse gold was well exemplified in checking over the mining returns from a previously bored deposit in Central Otago, N.Z. While the working returns are always liable to vary considerably from bore values in any particular sub-section of an area, still, over any considerable area, the two must check within small limits, if profits are to be calculated and capital raised on the average value given by boring.The present figures have probably more value than those from, dredge returns since accurate measurements are difficult to obtain in irregular water-filled dredge paddocks, whereas in the case under review the paddock walls stood almost perpendicular, and, as the measurements were taken and checked in the empty rectangular excavation, the yardage estimate may be taken as substantially exact.NATURE OF DEPOSITThe area consists of a narrow valley deposit of fluvio-glacial origin, the original deposit having been eroded and the gold reconcentrated by post glacial rivers. The wash is between 80 and 90 ft. deep, and is formed in two distinct layers:(i.) The top layer from surface to 70 ft. or 80 ft. consists of about equal quantities of gravel mixed with glacial drift, and a small amount of clay. The gravel is typical discoid glacial stone of a maximum size of about 4 in. diam. by 1 in. thick, and consists of soft micaceous schist and laminated slate. This upper layer of wash contains no coarse gold whatever, and very little fine; indeed, in mining, the top 30 ft. is discarded without being passed over the boxes.(ii.) The lower layer of wash to bedrock is similar to the upper, except iihat it contains about 10% of larger discoid stone up to 12 in. diam. by It in. thick; 90% of the gold is concentrated in this bottom layer.

Jan 1, 1929

By DV Boger

Rheology is the science which deals with the deformation and flow of matter. Thus nccology is concerned with the flow of any material. The mining industry is concerned with digging things out of the ground, extracting the good stuff and throwing away the had stuff. In the upgrading processes associated with mining, is mineral processing, wet techniques are used where the primary material being handled is a particulate fluid, ie a suspension. After the processing operation, with the concentrates extracted, what is left behind generally is a wet material in suspension form, which may or may not contain reagents harmful to the environment. The amount of waste generated in any of the mining processes is large, in fact, the mining industry is the largest generator of solid waste in Australia. In order to minimise the waste generated within the industry it has become of interest to handle the particulate fluid wastes, or suspensions, at high concentrations, thus removing water and some of the reagents which may be harmful to the environment. The resultant highly concentrated suspension is a non-Newtonian hold Rheology deals with the flow of non-Newtonian fluids; therefore i combination of rheological understanding of high density suspensions. ill conjunction with an understanding of the environmental problems hero' faced by the mining industry, can and has led to improved methods of waste disposal in the industry, ie waste minimisation. This paper describes the progress that has been made in the development of dry disposal technology in the mining and minerals industry in Australia.

Jan 1, 1998

The development of Mount Isa Mines Limited power supply is traced through the history of the mine operations. As would be expected, growth of the power supply system follows closely the increase in mine output, although it will be seen that total kWh. produced per ton milled shows a considerable reduction in later years when the mine output showed a more rapid rate of increase. That this reduction is not more marked is possibly due to the increased community and Shire Council power usage per head of population.INTRODUCTIONThe geographical position of Mount lsa, far from any large regional power supply Authority, dictated the policy that the Company be responsible for the production and suppiy of all power required for the plant operation. The Company also, in November 1937, accepted responsibility for the supply of a part of the power requirements of the township of Mount Isa. The history of power supply to the Mine may be divided into several phases.1. The supply Of lighting and power during the first plant construction period 1929-1931.2. The construction of the first section of the Mines Power Station, comprising Nos. 1 and 2 turbo alternators and boilers.3. The addition of No. 3 turbo alternator and boiler.4. The addition of No. 4 turbo alternator and boiler.5. The addition of No. 5 boiler.6. The addition of a. 2 turbo blowers for air supply to the Copper Smelter converters; b. 1 turbo blower for air supply to the L.ead Smelter; c. 2 turbo compressors for compressed air supply to the Mine and surface plant.

Jan 1, 1961

Christmas Island contains large deposits of phosphate minerals varying from high-grade calcium-phosphate (apatite) to lower grade iron and'aluminium phosphate (crandallite/millisite). The surface material is dominantly C-grade (Fe/Al) phosphate profiling into B-grade, a variable mixture of C- and A-grade ores, before reaching the high A-grade phosphate (apatite) which overlies a limestone Karrenfeld Base formation. A-grade ore is the basic phosphate used for the manufacture of superphosphate and phosphoric acid, whilst B-grade contains amounts of iron and aluminium which are unacceptable for these acidulation processes. Research into methods of separating the finer iron and aluminium phosphates from the coarser calcium phosphates has led to the development of wash-screen processes enabling recovery of 50 to 60%, as A-grade phosphate. Developmental stages included laboratory investigations, mineralogical studies, pilot tests leading the initial 20 tph prototype production unit and the current 100 tph production wash/screen plant, commissioned early in 1970 at Christmas Island.

Jan 1, 1971