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By Mizuta T, Sakurai M

The Pine Creek Inlier produced 12 440 kg of gold in the period from the first gold discovery in the 1860s to the early-1900s. During the 1930s renewed large-scale prospecting took place and gave a foothold for today's gold mining operations. The rise of the gold price and improved mining methods in the 1970s and 1980s made possible low cost, bulk low grade mining operations. Various gold deposits including vein, network and stratiform types occur in the Pine Creek Inlier (Nicholson and Eupene, 1990). The Tom's Gully deposit is located 100 km south-east of Darwin in the Northern Territory. It is hosted in the early Proterozoic Wildman Siltstone and lies north-east of 1800 my old Mt Bundey Pluton (Figure 1). Around the Mt Bundey Pluton, there are several prospective base and precious metal deposits such as Quest 29. The Tom's Gully gold deposit was discovered in 1986 and yielded a total of 3070 kg of gold from ore averaging 9.35 g/t gold between 1987 and 1990 when the mining operation was terminated.

Jan 1, 1994

By Griffin PT, Espinosa-Gomez R, Jameson GJ

Two major issues are to be addressed in the Copper Concentrator of Mount Isa Mines Limited. The first of these is the need to increase concentrator flotation capacity to increase copper recovery, while the second is the need to reduce the iron sulphide dilution to meet future smelting requirements. Extra capacity in the cleaner and retreatment sections of the concentrator have been identified as key target areas, with additional copper recovery of at least one per cent identified from plant trials. Extensive pilot plant tests have been undertaken to evaluate the performance of the Jameson cell compared to conventional mechanical cell and column circuits. This work has shown that Jameson cells present an opportunity to achieve the desired grade and capacity specifications at lower capital cost than available alternatives. This paper outlines metallurgical results of work undertaken in the Copper Concentrator, together with a summary of pertinent Jameson cell operating parameters investigated during the period.

Jan 1, 1993

By Kyle J. H, Browner R. E

The selective adsorption of gold cyanide by the weak base ion exchange resins, PAZ-4* and Duolite A-7*, the neutral polymeric adsorbent, Amberlite XAD7*, and the strong base resins, PAZ-8 and IRA-400+ have been studied in both low and high salinity waters, and performance compared with activated carbon. The selectivity of the neutral polymeric adsorbent and activated carbon for gold decreased in highly saline water, while the selectivity of weak and strong base resins for gold increased in highly saline water. This supports the contention that the adsorption mechanism for neutral polymeric adsorbents and activated carbon is the same. Copyright

Jan 1, 1992

The economic viability of many Southern African massive mining operations is threatened by excessive dilution. In many operations currently in progress, some stopes are experiencing as much as 115 per cent waste ingress reporting to drawpoints. This paper examines the magnitude, causes and types of dilution and presents a set of general principles for the control of dilution in massive stoping operations.

Jan 1, 2000

By S Hapugoda, H Han, L Lu

Charcoal produced from Syzygium Zeylanicum trees was widely used in ancient Sri Lankan iron smelting practices. Charcoal made from Syzygium Zeylanicum tree trunks, branches and leaves were analysed by optical mineralogy and SEM and found to contain unusually high concentrations of calcium oxalate (CaC2O4.H2O – CaOx) crystals in plant cells. Partial and full reduction tests of a high-P Brockman ore were conducted at several temperatures with coke and coke doped with CaOx and CaCO3. It was observed that CaOx promoted reduction and generated comparatively more metallic iron in reduced samples. Furthermore, CaOx encouraged phosphorous partition into slag phases than into the metallic iron, suggesting CaOx can a potential alternative fluxing material to calcium carbonate for treating high-P iron ores in ironmaking processes.

Sep 18, 2023

By R Neivandt, Kane, M O&apos, D Browne

Newmont Australia is the operator of the Mt Leyshon mine near Charters Towers, Queensland. Mt Leyshon is an open cut gold mine, which processed on average 5.0 Mt of ore and produced up to 250 000 ounces of gold per year. Mining was completed in early-2001, followed by treatment of low-grade ore stockpiles for a further 12 months. Approximately 250 ha of waste rock dumps have been rehabilitated. Rehabilitation of two of the three tailings storage facilities (TSF) has been completed and the third is in progress. A field performance monitoring system that includes an automated meteorological station, large-scale lysimeters (measurement of net percolation), and in situ moisture content sensors (measurement of moisture storage changes in the cover material) were installed to monitoring performance of the cover systems placed on the waste storage facilities. This paper focuses on the installation and calibration of the in situ moisture monitoring system. The moisture monitoring system provides automated detailed in situ volumetric water content data above and within the large-scale lysimeters. A portable unit that provides spatial in situ moisture content measurements at additional locations on the cover system is also utilised. The paper will focus on installation and calibration of the in situ water content monitoring instrument in the waste rock, coarse cover material, and fine textured cover materials of the tailings facility and waste rock dump cover systems.

Jan 1, 2003

By Fukuichi K, Matsukawa H, Nakagawa M

The Myojin Tunnel, located on the Shikoku Expressway being constructed by the Japan Highway Public Corporation, is 3,770 m long with a cross sectional area of 80 m2. Kajima Corporation, the contractor for the northern construction section of this tunnel, adopted here its newly developed "mini-bench" method of excavation. The objectives of this method were 1. to be able to perform all tunnelling operations using the whole cross sectional area of the tunnel under any ground conditions, and 2. to be able to vary the length of the mini-bench within the range of 0 to 7 m according to ground conditions. In order to achieve these objectives, original, sophisticated equipment was developed and employed in the work. One of the newly developed machines is a special jumbo, a hydraulic crawler jumbo with five rotary type booms. This machine is capable of accommodating variation in the length of the mini-bench accompanying changes in ground conditions and is equipped with a special mechanism by which the positions of the booms can be controlled by means of hydraulic cylinders. Also developed was a shotcrete robot for use with the mini-bench method which has the control board near the shotcrete nozzle for close control of application.

Jan 1, 1987

By Slater R

The initial planning and detail design phase leading to the development of a 7.5 m internal shaft to service the deep 3000 and 3500 copper orebodies at Mount Isa, Queensland is well advanced. The choice of internal shaft access was made over alternative methods such as a decline from existing levels and borehole hoisting. The resulting access development requirements and shaft configuration for production have been determined. Several techniques are being studied for shaft development. These include the application of blind shaft drilling and large hole reaming methods as well as conventional sinking techniques. As the 3000/3500 Orebodies extend from 1000 metres to more than 1800 metres below the surface, high stress conditions and ground temperatures ranging from 45CC to 62CC are anticipated. The effect of these on the methods being investigated to create a favourable working environment will influence the final choice. Exploration diamond drilling is in progress to confirm the geology of the orebodies so that planning for their extraction including refrigerated ventilation concepts can proceed.

Jan 1, 1982

By Hocking G

For some underground structures, the use of the plane strain assumption in stress analyses may not be justified. The finite element method and photoelasticity have been used to obtain complete 3-D solutions, but, for various reasons, neither method has found universal use. The boundary integral equation method (B.I.E.M.) can be more efficient and economical than the finite element method for 3-D problems involving large volume to surface area ratios. A B.I.E.M. program developed for calculating stresses and deformations in infinite elastic media has been used to determine the 3-D distributions of stress around T- and Y- junctions of circular tunnels in stress fields in which the ratios of horizontal to vertical stress are 0, 0.33, 1.0 and 2.0. For the T- junction considered,stress concentrations at the intersection are approximately twice the plane strain values. Except where horizontal field stresses are high, the stresses in both tunnels approximate the plane strain values at about two tunnel diameters from the point of intersection of the tunnel centre lines. The stresses in the two branches reach those for the corresponding plane strain, two parallel tunnel case two diameters from the point of intersection of thq inner tunnel walls. Very high stress concentra- tions occur in the pillar of rock between the inner tunnel walls near the point of intersection.

Jan 1, 1976

By J Janus, J Krawczyk

Local accumulation of methane in workings of a longwall is one of the most common causes of mining accidents. This gas has many sources: it may leak from goaf through permeable sealings, or through gaps between roof support sections. This stream is then mixed with ventilation air. In the case of auxiliary ventilation ducts, or free jet fans, we have to consider the propagation of a clean air stream in areas with an air-methane mixture. Therefore, modelling the mixing process of methane with ventilation air is important for determining the hazardous areas and thus to ensure safety. Computational fluid dynamics (CFD), specifically the finite volume method, provides tools for such modelling. However, this method requires validation. For this purpose, we have compared measurements with simulations for selected test cases having sufficient similarity to the present problems. In typical methane explosion hazard areas, such as a longwall, it is difficult to make measurements sufficiently to confirm credibility of 3D CFD simulations. As a relevant alternative, an injector methane drainage station placed in an underground gallery has been selected. The stream of drained goaf methane is entrained by compressed air powered injectors and then mixed with ventilation air. Research in this area does not interfere with mining operations, it can be performed safely in a repeatable way. Flow within the site has many similarities to conditions in mine drifts of the longwall area. Comparative research of measuring the methane concentration distribution in the mine drift downstream injector station, with simulations of propagation of the methane stream, was carried out. For measuring the methane concentration distribution in the mine drift a multipoint measurement velocity system developed at the Strata Mechanics Research Institute was used. For the simulation a finite volume method for turbulent flow of gas mixtures was applied. Preliminary results of comparison are shown as graphs and tables.CITATION:Janus, J and Krawczyk, J, 2013. An analysis of the mixing of air and methane in the stream produced by the mine injector station - Presenting preliminary results of measurements and modelling, in Proceedings The Australian Mine Ventilation Conference , pp 49-56 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 1, 2013

By Nilsson C

Man has always been and will always be part of his environment, in ,a good, bad or indifferent manner. Until quite recently, this environment has been the atmospheric boundary layer above the land masses, and to a limited extent the air-sea interface of the oceans. Since the days when he lived in caves, he has built up a wealth of observations on these two environments,-with ever-increasing scientific precision which unfortunately until quite recently was completely insufficient for modern capabilities of data analysis. Consequently, in a sense, he has left in his wake thousands of years of missed, opportunities for making exact observations and increasing his understanding. The data of the past are lost and he has to be satisfied with what he can assemble from now on when his environ- ment, largely as a result of his actions, is exhibiting more and more rapid variations in time; in other words, time series of observations of phenomena are required, the length of which is critical for most purposes of analysis.

Jan 1, 1970

The brown coal resources of the Latrobe Valley, which include over thirty thousand million tons of coal suitable for open cutting, provide the main source of fuel for the power generation for the State of Victoria. They also provide the basis for the development of a supply of cheap hard fuel for industrial and domestic use, and for the development of the Lurgi process for manufacture of town gas for most of the State. The production of hard char for metallurgical processes and liquid hydro carbons will each, no doubt, play its part in the industrial growth that will be based on these resources.The State Electricity Commission of Victoria, which has been allocated the task of developing these deposits since the early 1920's, is faced with problems of economic selection of deposits for development, and excavation and transport of huge tonnages of coal and overburden-in this year, 19'59, about 12,000',000 tons of brown coal will be won, and over 7,000,000' cu. yd. of overburden will be removed in the four open cuts operated by the Commission; by 1967, eight years from now, the demand will have doubled.This paper deals with the nature and importance of various factors effecting the planning of the development of these resources. It is in essence an introduction to the papers by C. S. Gloe, H. C. G. Rodgers and J. M. Alexander, also being -presented at the Institute conference in Victoria in August, 1959.INTRODUCTIONIt is the intention in this paper to define the factors that come under consideration in the planning and development of the brown coal fields in the Latrobe Valley, whose exploitation by the State Electricity Commission of Victoria was initiated almost 40 years ago. It is proposed to enumerate, and in sorile cases evaluate, the physical and economic criteria that play their part in determining planning for the future.

Jan 1, 1960

By Trueman R

If continuous mining systems are to be successfully applied in metalliferous mines then reliable models will be needed to predict rock cutting machine advance and tool wear rates for effective machine selection before mining commences. Many of the predictive models developed to assess cuttability in situ are over-simplistic. As a result they tend to be both site and/or machine specific. Nevertheless very detailed models have been developed for full face machines which are capable of accurate cuttability predictions in a variety of rock mass conditions and for a variety of machine and tool configurations. However, models to predict productivity and tool consumption for partial face machines are not as well advanced. There is a need to develop reliable models for partial face machines such as Roadheaders, the Robbins Mobile Miner and the HDRK-Wirth CMM, as these types of machine are likely to predominate in a mining environment. The paper outlines the current state-of-the-art for predicting cutting machine performance and the work being carried out within the Centre for Mining Technology and Equipment (CMTE), in collaboration with the Australian mining industry, to advance our capability in this area.

Jan 1, 1995

There is a difference in design aspects between steel linings and rubber linings for grinding mills. The basic design rules for rub- ber are described as well as the liner designs for different applications.

Jan 1, 1978

The design of mine ventilation systems for the BHP Steel Division Collieries is based on the acquisition of ventilation survey data for the establishment of a realistic computer net- work model. The branches which form the net- work for the computer models are calculated from a range of resistance factors incorporat- ing both a frictional and shock loss component. Since shock losses can account for up to 30 per cent of the total energy losses in mine airways the use of friction factors alone without accounting for shock losses will result in the choosing of an insufficiently performing fan. Published tables of friction factors have in- variably been taken from metalliferous or single entry studies and consequently are not reliable for Australia's mining conditions where multiple entries with regularly spaced cut-throughs are the normal practice. Typical resistance factors for roadways of rectangular cross-section 5.5 m x 2.0 m, with coal sides, have been found to vary from 0.11 Ns2/m8/km where no timber supports are used, to 0.98 Ns2/m8/km where double centre legging together with wooden chocks is used. In addition to the range of resistance factors due to varying support methods, the nature of use for a roadway is very significant because of the condition of repair and upkeep maintained.

Jan 1, 1983

Quite often the reserve assessor becomes enamored with the numbers gen- erated and forgets the basis for his assessment. The quality of the assess- ment can only be as good as the quality of the input data. The use of seismic data from the Gippsland Basin in assess- ing Esso/BHP's oil and gas reserves is an excellent example of this principle. By significantly improving the quality of seismic data, a much more reliable estimate of a field's reserve potential can be made. In addition, it provides the basis for further delineation drill- ing which, as recent experience in Gippsland has shown, often leads to increased reserves.

Jan 1, 1979

Traditionally trucks have dominated haulage in open pit mines. Only recently have conveyors begun to be used in the long haul and high lift duties of surface mines. Steep angle conveyors are proven versatile systems for elevating or lowering materials continuously at steep angles to 90¦. This paper describes the design of a bucket-type steep angle conveyor that was developed as a joint research project between the Western Australian School of Mines and the Maanshan Institute of Mining Research in China. The steep angle conveyor can be used as a viable option for transporting blocky ore from open pit mines. A pilot conveyor was constructed and tested to determine its technical and operational feasibility. Furthermore, a computer model based on Matlab mathematical modelling software was developed to simulate the performance of the pilot conveyor. The model enabled to determine the design parameters of industry-scale conveyors to yield satisfactory performance. These conveyors become very cost-effective for those mines having large mine lives and depths greater than about 500 metres.

Jan 1, 2003

The use of teleoperation in mining is increasing due to requirements to improve safety and reduce the number of people required to work in remote and difficult environments. We recently completed a project to develop a teleoperated control system for a rock breaker at an iron ore mine in the Pilbara region of Western Australia, with the objective of demonstrating the feasibility of remote rock breaking over long distances. This required controlling both the rock breaker and an array of pan-tilt-zoom (PTZ) cameras using joysticks. Controlling the cameras distracted operators from the primary task of controlling the rock breaker to position and fire the hammer. This lengthened task times as both the operator's attention and their hands have to swap between different control interfaces. In this paper, we present a novel design using human eye gaze as an interactive input for the remote camera control. It follows a simple and natural design principle: Whatever you look at the screen, it goes to the centre. A prototype system has been implemented by integrating computer vision based eye tracking technology, with the advantage of being real-time, robust and marker-less. We conducted a user evaluation, where users undertook a control task while obscuring the direct view of the working area and using a remote camera to transfer the live video stream as the visual feedback. Subjects were required to participate in the experiment using eye tracking camera control and traditional joystick control respectively. The statistical analysis of objective measures indicated that our novel eye tracking control significantly outperformed the joystick control. The results of the post-experimental subjective measures also revealed much higher user preference for using eye tracking control, which provides clear evidence that this design is a better interface for remote camera control in mining teleoperation settings.

May 1, 2010

By Omnes G

Sixty Schlumberger electrical soundings were carried out in the Depot Springs area, near Agnew, Western Australia as part of an investigation into the availability of groundwater for the Agnew nickel project. The object of the survey was to locate calcrete aquifers related to Tertiary drainage channels on the Pre- Cambrian surface. The electrical soundings were initially interpreted using sets of master curves and auxiliary point methods. Electrical sections were produced and contour maps prepared of apparent resistivity for AB=80m, total conductance of the overburden and transverse resistance.

Jan 1, 1975

The program, WASTRT 70, was set up specifically to handle the design of tunnel liners and underground structures where inter- action between rock and structure significantly affects the design. It may however be used for any mass/R.C. structure capable of being simulated by straight line elements between modes and with loading restricted to nodes. The analysis system adopts typical elastic/stiffness matrix methods. Two main mass/R.C. design segments are utilized (1) Design of section depth based on maximum required stresses and optimum steel/concrete ratios. (2) Design of reinforcement for a given section depth with concrete stresses given for mass and water code structures. Each design segment covers shear, minimum principal stress on ~ , heavy compression as per code (columns), heavy compression one-face steel (tunnel liners), tension and water code requirements for all moment/thrust/section depth ratios on rectangular sections.

Jan 1, 1976