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By Lysnar R, Horswill M

Since the introduction of the pocket calculator, electronic measuring equipment, lasers and computers, the mine surveyor's approach to his work has changed. Where he once used steel bands he now uses infra-red, visible light or radio waves. The reading and storing of angles is done automatically and he now has to be familiar with the facilities that a computer can offer, instead of plotting and calculating manually. This highly sophisticated equipment is continually being upgraded, modified and fine tuned. This paper will attempt to highlight some of the equipment at present in use by the surveying profession and research currently being conducted by the WA School of Mines. The various options in EDM will be considered including the latest unit capable of measuring distance without the benefit of a reflector, thus enabling the surveyor to co-ordinate points that were previously thought inaccessible. The School is currently working on changes to the GAK1 Gyro Theodolite which may improve results and enable the operator to have more control and confidence in his observations. Areas under consideration are improved lighting, binocular viewing and interfacing the instrument to a stopwatch. In the last few years the computer is being used not only for surface pickups and control but also for underground work. We will highlight the underground options in this area and the software available.

Jan 1, 1987

By J M TORLACH

Learning is an iterative process, and we might reasonably expect that after more than a century of mining during an era of sustained technological development, (following a millenium or two of unrelieved hard physical graft), that the more obvious physical hazards could by now be competently managed. It is perhaps a reflection on the perversity of human nature that we have not fully learned our lessons in this exacting environment, and that worse, we have still too often failed to profit by the experience of those lessons. The more obvious underlying factors which impact on this situation are examined briefly, as a prelude to consideration of some outstanding examples of recurrent problems experienced in recent years. Reasons for the continued existence of sub-standard practices are outlined, with a focus on the human element, and finally proposals for appropriate remedial strategies are summarised. This paper therefore seeks to examine and discuss some of our deficiences and to suggest some directions for the way ahead.

Jan 1, 1992

By M J. Nugus

The structural models developed by exploration and mining geologists are most commonly concerned with the ‘main structures’ or key constituents that pertain to the associated mineralisation. To this end, it is recognised that the geological and exploration models, which are developed, are essentially ‘fit for task’ and the scale-related variances are not always realised at an early stage. In fact, in many cases anomalous intercepts along different trends and of variable apparent continuity have often been neglected as ‘back scatter’ and not important. Recognition of the importance of subordinate structures as mineralising hosts suggests that additional opportunities exist outside the primary and main structures. History shows that opportunities are often not realised where gold is hosted in orientations not parallel to the predominant trend of the schistosity, main fault or shear zone.Another reason for the importance of subordinate structures can be understood from their roles in a percolation network. Subordinate structures can access the large fluid fluxes provided by backbone elements, but, as dangling elements, they provide greater opportunities for gold precipitation mechanisms and hence may constitute essential parts of the resource. Therefore, the role, understanding and consideration of the smaller-scale and orthogonal structures should be considered during all facets of exploration, resource development, delineation and mining.

Aug 22, 2011

By D Reid

The engineering properties of soils and tailings often exhibit significant anisotropy. One area where this has been well documents is undrained shear strength. Materials sheared in directions close to the principal stress direction in situ, i.e. triaxial compression, typically exhibit higher undrained strengths than those sheared in other directions such as simple shear. Importantly, along the most common critical failure surfaces relevant to tailings stability, whether primarily through tailings or a critical foundation layer, saturated materials are generally much closer to the simple shear loading direction than triaxial compression. Therefore, testing undrained shear strength of tailings or foundation soils in triaxial compression is likely to result in overestimation of the relevant strengths for design. Although these issues have repeatedly documented in the geotechnical literature for over three decades, they are not appreciated sufficiently across our industry. In an attempt to address and highlight these issues, a review is carried out of historical reference to the importance of simple shear loading. Attention is then drawn to the techniques applied in three recent post-failure investigations, where simple shear testing was applied. Finally, some relevant laboratory test results from a recent project in which the author was involved are outlined.CITATION:Reid, D, 2018. Importance of the simple shear loading direction to the stability of tailings storage facilities, in Proceedings Mine Waste and Tailings Stewardship Conference 2018, pp 274–284 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 23, 2018

By S Jahn, M Noel, E M. Rykaart, M Pau

Three soil cover test areas were constructed on waste rock backfilled into the Lichtenberg Pit, near Ronneburg Germany. A fourth, uncovered area was included as a control. Each test area measures 50 m by 65 m, and was constructed using full-scale equipment and construction practices. Extensive material sampling and testing was included as part of the construction. Devices were installed in each plot to monitor meteorology, infiltration, run-off, interflow, soil moisture, soil temperature, and soil pore gases. Boreholes were completed in each area and instrumented for temperature, pressure and pore gas sampling to a depth of approximately 60 m. Data from the monitoring instruments have been collected since July 2000, and have been comprehensively analysed and modelled on two occasions. The paper presents an overview of the test area design and instrumentation and the results of the two comprehensive data reviews. The reliability of the various monitoring methods is discussed and experience with several innovative methods is reviewed. The difficulties encountered in modelling the data set using common soil physical models are discussed.

Jan 1, 2003

By Medhurst TP, Trueman R, Hutchinson IN

A breaker line support (BLS) monitoring system, BLSmon, has been designed and constructed by the CSIRO and installed and commissioned at Laleham No.] Colliery, Queensland. This system was designed to record hydraulic leg pressure and canopy position measurements and relay these, in real time, to the surface. The system has shown itself to be capable of operating on the BLSs without any adverse affect on production. Analysis of the results of the monitoring exercise has shown that rate of change of leg pressures on the BLSs could be used as an aid in the prediction of adverse mining conditions. Under favourable mining conditions the supports were observed to initially unload from the set pressure, this unloading reduced with time and by the end of a typical lift cycle had either ceased or reversed slightly. This behaviour was considered to be due to one of four possible causes, these being; the compaction of floor debris, and/or compaction of the floor, and/or crushing of the roof and /or support creep. The actual cause can only be determined through detailed monitoring of both roof and support convergence. However observational data would suggest that compaction of debris and softened floor material beneath the supports was the most likely cause. The few positive loading rates recorded under these conditions were of short duration and occurred towards the end of individual lifts. Where mining conditions were unfavourable the negative rates of change of pressure, unloading of the support, were reduced throughout a lift, in both duration and magnitude, when compared with favourable mining conditions. Over the same period the positive rates of change were observed to be greater. The rate of change of loading and convergence can be utilised to identify the onset of instability in the lift area. However, before this facility can be utilised by the mine for the reliable prediction of instability more monitored data and sophisticated processing techniques are required.

Jan 1, 1992

By MacDonald AJ, Raffield MP

The South Deep massive orebody consists of 20 to 30 in of payable conglomerates ranging in dip from 11¦ to 20¦ and at depths of between 2400 in and 34(10 in. The mine design process selected a mining method with a proven record of application that could be adapted to overcome the inherent difficulties associated with the depth, thickness and structural influences of the South Deep orebody. A modified cut and fill mining method provides a concentrated and highly flexible method of extraction. An integrated destressing cut will enable the modification of the stress environment such that it is suitable for massive mining operations. The choice of backfill type and stoping width in the destressing cut ultimately determines the characteristics of the stress modification and, as such, is critical to the success of the cut and fill operation. This paper discusses the decision process undertaken to determine the optimum backfill type and stoping width combination in terms of, conditions in the destressing cut faces and in the massive mining environment. Numerical modelling has been extensively used to analyse arious scenarios to aid in the decision process.

Jan 1, 1998

By M DellÆAmico, K Vining

The iron blast furnace is the most widely used and efficient producer of liquid iron; however, emissions from sintering and coking cause environmental pressure for the integrated steel works. The combustion of coke fines (breeze) during sintering contributes to greenhouse gases (GHG) (eg carbon dioxide) and is a source of SOx and NOx emissions. Coking capacity is also constrained by environmental concerns and economic factors, such as increased coke consumption, and short supply is leading to high prices. Improved coking practices, which result in reduced production of fines, are also contributing to the tight availability of breeze for sintering. This combination of factors presents an opportunity to consider alternatives to coke as a fuel for sintering. CSIRO Minerals has been investigating the use of wood biomass/char as a substitute for coke during sintering. Wood biomass, or char produced from it, is an attractive carbon source as carbon dioxide liberated during combustion can be sequestered back into growing biomass. It has great potential to reduce the emissions from integrated steelworks and improve their environmental acceptability. Harvested biomass/char is also a renewable and sustainable resource and can be integrated with good land management practices such as remediation of salinity affected land. Weeds, especially woody weeds, can also be used as a source of biomass for charcoal, and integrating char production with weed management can help address a pressing environmental issue in Australia. Previous reported preliminary testwork indicated that the use of Red Gum char as a replacement for coke resulted in a product sinter of comparable quality, improvements in productivity and significant reductions in SOx and NOx emissions. In the latest testwork, CSIRO has examined the properties of a range of potential charcoals, and has conducted a further series of granulation and small-scale sintering trials with them in simulated Japanese Steel Mill iron ore blends. Sinter fuels characterised and evaluated include industry sourced coke breeze, commercially available wood char and a charcoal from prickly acacia (acacia nilotica). Prickly acacia has been declared a noxious weed, is widespread in Australia, and is classified as a æWeed of National SignificanceÆ. The results presented in this paper support the notion that charcoal outperforms coke in many aspects of iron ore sintering and factoring in environmental considerations makes the switch to charcoal even more favourable.

Jan 1, 2005

By Ketelaar P. B, Nichols S, Power W. L, Utley D. C

The impact computers are having in geoscience is distinctly mixed. In the petroleum industry where much of the data are based on geophysics, computers have become an integral part of exploration and reservoir evaluation and simulation. In the minerals industry, the trend to computerisation is more advanced in some disciplines than others. Geophysical and remote sensing data are routinely processed and imaged using state of the art computer techniques. Mine surveying, planning, design and resource and ore reserve estimation are now all predominantly reliant on computers. However senior management of many companies, particularly in the mineral exploration industry, are still reticent to fully embrace the technology. 3D computer modelling of geology and orebody delineation is still largely in its infancy. Two current and significant drawbacks to the routine use of computer modelling of geology in both mining and exploration are the tedious and time consuming modelling process and the lack of seamless interaction between 3D computer-aided drafting (CAD) software and geographical information systems (GIS) which are largely 2D in their data treatment. There is an urgent need for a 3D spatial information system (eg 3D GIS) with intelligent and rapid modelling functionality. One of the keys to the successful building of 3D geological computer models begins with data base structure and design to ensure that there is no loss of data fidelity through data capture, storage, manipulation and modelling. Once a model is constructed, the latest generations of visualisation software provide sophisticated environments over a range of hardware platforms for visualisation in both mono and stereo viewing. This is demonstrated by the geological models which are presented in the digital interactive version of this talk whose URL on the World Wide Web is: http://www.ned.dem.csiro.au/FRACTAL/pubs/talk97AUSIMM/

Jan 1, 1997

The underground coal mining industry in Australia has, in the last 30 years, undergone a revolution in production methods, techniques and results probably unparalleled elsewhere in the world. It can lay claim not only to leading the fight against pneumoconiosis and setting high safety standards generally, but has at the same time recorded comparatively high rates of increase in output per man shift. The latter has been achieved as a result of progressively matching the latest in production and underground transportation equipment with significant changes in seam development and extraction techniques and the introduction of stress-relieving extraction methods unique to the world scene. However, the seam recovery factor is still too low. Apart from the overall objectives of maximising production and commercial returns with the greatest safety, there must be a concentration towards maximising seam recovery, particularly in high seams. The search will continue for systems which are more completely continuous mining operations than the present stop-go operations, with longwall having long term potential in this regard, but as yet not sufficiently developed to engender confidence for its more general use. Techniques developed in the last 10 years make the development and extraction of deeper seams, perhaps to 2500 feet or more, feasible with continuous miners as well as longwall. The future will see a greater use of continuous shifts at mines, larger mines with more sophisticated management organisation, extensible belts at the face, better systems of immediate roof support at the face, remote operation of face equipment, greater use of roof bolts and the longer roof cables. With commercial confidence in coal mining now virtually assured to at least the turn of the century, the stage is set for heavy capital development in the industry which will undoubtedly include major research into the whole area of mining methods and equipment. We must ensure that our contribution to such research equitably matches other coal producing countries.

Jan 1, 1975

Although this is a symposium on "The Occurrence, Preparation and Use of Australian Black Coal", I do not think that, in these days, any of the main energy resources can be considered only in terms of country of origin or only by itself in isolation from other energy resources. Accordingly, I propose to comment on solid fuels generally in the world energy scene, and make some brief references to Australian solid fuels, and to some other matters in the latter part of this paper. In this address I am drawing heavily on the 1974 survey of energy resources published just recently by the World Energy Conference. I do this for a number of reasons. Firstly, the survey is the latest and most comprehensive publication of its kind; secondly, it is the result of several years' work by a panel of eminent people, from all the energy industries and from some 16 widely spread countries; thirdly, substantial assistance was given by the U.S. Atomic Energy Commission in its compilation; and, finally, to let all know of the existence of the book, as I believe it to be a source document for all those interested in world energy resources. The United Nations "J" series of statistical papers provide important information on the annual production and consumption of and trade in the various forms of energy. In their respective areas, these two publications are primary information sources. Our present sources of energy throughout the world are fossil fuel deposits (coal, oil, gas), nuclear materials, water, geothermal, solar and tidal - but we are at present heavily dependent upon the natural stores of non-renewable fossil energy resources. Fig. 1 shows the changing use of energy resources in the present century. A comparison between 1900 and 1973 shows clearly the shift which has taken place.

Jan 1, 1975

By D P. Blair

The theme of this conference is blasting productivity. This article only considers the technology aspect of this theme, and in particular, the collection and analysis of experimental data. In many cases, field trials are set up to collect data on variables such as fragmentation and vibration with the aim of comparing different explosive products and/or blast designs. An important aspect of such trials is the collection of sufficient data to draw sound conclusions. In this regard, there is no doubt that the scatter in real data is the root cause of all problems of obtaining misleading results due to an insufficient number of trials. This article shows that the typical one-off trial has a high probability of producing misleading information, which could be considered to be worse than having no information at all. Assuming that sufficient data has been collected, this article also highlights the methods that can be used to make the most of that data. These methods include the application of appropriate statistics that are dependent on the nature of the scatter in the data, and the use of some of the more recent filtering and spectral approaches that can be used to reduce the noise in measured blast signals and increase the resolution of their spectral characteristics.

Nov 8, 2011

The carbonatite-hosted apatite deposit at the Cajati open pit mine in the Jacupiranga igneous-carbonatite complex is located in south-eastern Brazil. The major styles of apatite mineralisation include veins or veinlets, small pods or patches, disseminated apatite and locally massive aggregates. The metallurgical concentration of the apatite is accomplished by grinding the carbonatite, removal of magnetite with a magnetic drum, size classification with cyclones and flotation to suppress carbonates and collect apatite. To examine the character of the apatite grains and to apply those observations to apatite beneficiation, specimens of carbonatite were collected from recent exposures in the mine and from selected drill holes. This study utilised a variety of microscopy methods, including transmitted and reflected light, cathodoluminescence (CL) and scanning electron microscopy with wavelength-dispersive spectrometers for mineral compositions. It was found that LREE, Na and Sr are the main elements replacing Ca in the apatite, with relatively low oxide contents (<0.5 per cent, but up to about one per cent for Sr). LREE and Sr contents consistently increase in the latest intrusions (C4, C5 and SP24). Chemical and morphological modifications of apatite were recognised to be related to detrimental effects on flotation recovery. Three examples illustrate this relationship: 1.  Apatite with reddish CL is fractured. Locally that apatite exhibits no CL due to CL quenching caused by iron entering the apatite structure.2.  Apatite from the xenolith-rich area exhibits abundant fine, platy silicates that appear to interfere with flotation and lower apatite recovery.3.  So called æhardÆ apatite, which is more difficult to grind, occurs in an area in the mine that was affected by hydrothermal activity. That activity is evidenced by the development of a bright, white CL rim in the apatite, and by the presence of late veins of carbonates and sulfides that fill fractures and appear to contribute to higher cohesiveness of those apatite grains.

Jan 1, 2008

By T A. Helms, P Gottlieb, S E, R Bateman

In response to the ever-increasing challenges facing the modern gold mining industry and the need for improved gold recoveries within all processing streams, CSIRO has upgraded its latest automated mineralogical analysis system, QemSCAN (formerly QEM*SEM), with special purpose hardware that speeds up the location and measurement of precious metal-bearing phases. By rapidly scanning the surface of polished blocks, and accepting only fields that contain the minerals of interest, QemSCAN is able to find, map, and quantify target minerals in extreme detail. Phase identification and quantification is achieved by placing a grid of points over the target particle and collecting X-ray information at each analysis point. The resulting mineral maps provide the metallurgist with a complete textural description of all gold-bearing phases within the product measured, together with quantification of the gold phases in terms of their modal abundance, particle size, mineral associations, relative contributions to gold deportment and liberation characteristics. Examples are presented which illustrate how QemSCAN is able to find and quantify gold-bearing phases within low-grade ores from the Super Pit, Kalgoorlie. This work is the result of a collaborative project between Kalgoorlie Consolidated Gold Mines (KCGM), CSIRO Minerals, and the University of Queensland, and is on-going.

Jan 1, 2000

Throughout the Kalgoorlie Field the dominant factors influencing all planned exploratory work are: firstly, the general geology of the district, and, secondly, the lode fracture pattern. Superimposed on these, there are innumerable faulting problems which tend to complicate the search for ore.In this paper it is proposed to deal primarily with the lode fracture pattern and to touch on the general geology only insofar as it affects ore distribution. So much has been written on Kalgoorlie geology that it would be impossible to review the literature adequately in a brief paper such as this. The basic facts of rock types and rock distribution are well established and the broad structure of the field is known in the central portion, though it is less well established towards the northern and southern ends.The latest descriptions of the general geology are those of Stillwell (1), and Gustafson (2), -and these represent the basis of current knowledge.GENERAL GEOLOGY.The field is six miles long and about one mile wide, the long axis trending north-west. The "Golden Mile," or heart of the mining 'area, covers a length of three miles in the southern section, and consists of a central core of quartz dolerite greenstone which merges into uralitic quartz 'dolerite on its western margin. The uralitic quartz dolerite is derived from an original quartz dolerite by a low grade...

Jan 1, 1948

This paper presents a review of computer techniques for the automatic contouring of geological and geophysical data with output as interactive display on graph plotters or graphics terminals and passive display on automatic drafting tables. The advantages of the method of fitting a triangulated surface to randomly distributed data using an advancing front algorithm are described, as well as the technique for determining interpolated values for the production of contour line segments and a contour smoothing algorithm. This contouring method is employed by the Geological Survey of Queensland and is implemented as an interactive system. An alternative method ideally suited to randomly distributed data involves the use of piecewise parametric cubic splines. This method which is ideal for sharp variations in magnitude and areal extent typical of geophysical anomalies is discussed. The mathematics of surface interpolation using non-parametric splines and an explicit piecewise surface fitting technique are discussed. Curve tracing techniques which are suitable for automatic contouring are also presented and the inherent advantages of interactive contouring using on-line plotters and graphics terminals for previewing of displays are described.

Jan 1, 1977

By Nikaido M, Kanda Y

A rotary type separator has been developed which separates particles on the basis of their shape. This separator was applied to a particle size range of about 50 - 120 ¦m, and to our present knowledge may be the smallest size range ever to be separated. A theory of the separation is given based on the difference of an adhesive force of the particles: the adhesive force between spherical particles and plate is more powerful than that of irregular shaped particles for the same particle size. These facts have been ascertained by the measurement of an adhesive force by a centrifugal method. US and Japanese patents have been obtained on this separator, which consists of a borosilicate glass cylinder of 150 mm outside diameter, 120 mm in width, and an AC electromagnet. The samples used in this study were mixtures of spherical glass particles and non-spherical shaped glass particles. The results are summarised as follows. In the case of mixtures of spherical particles and irregular shaped particles in the weight ratio of 1:1, the spherical content of the spherical product became 70 per cent - 75 per cent, and in the case of 3:1, the content became 87 per cent - 90 per cent, as the result of one separating operation. However, for a mixture of somewhat rounded particles and irregular shaped particles of weight ratio 1:1, the rounded content varied between 58 per cent - 73 per cent. The feed rate of the particles mixtures was about 0.3 g/min. Newton's Efficiency was 20 per cent - 60 per cent. The separator may find application in shape separation of ceramic powder, metal powder or industrial diamond powder.

Jan 1, 1993

Drilling has disclosed a sequence of Cainozoic sediments immediately to the west of the Ediacara mineral field containing little or no dolomitic debris in the lower and middle sections, but with gravel beds of dolomite derived from local rocks in the upper part. It is suggested that the lower and middle sequence of Cainozoic strata was deposited over the area of the Ediacara Range, and that this range was uplifted, probably as a horst block, during Quaternary times and was first exposed to subaerial erosion during the upper Pleistocene epoch.Lower Cambrian dolomites with associated stratiform lead mineralization, which formed the target of drilling on the western downthrown block of the Ediacara Fault, were eroded before deposition of Cainozoic sediments.Intense leaching of basal Cambrian dolomites around the periphery of the Ediacara Basin took place during Mesozoic and Tertiary times. This leaching process has resulted in enrichment of copper and lead mineralization in a thick marginal zone of residual clayey material overlain by dolomitic collapse breccia. These zones of leaching and enrichment were preserved under Cainozoic sediments which have subsequently been eroded. The Ediacara Fault appears to have been a major conduit for mineralizing fluids and is the main lineament of the Torrens Hinge Zone. Contemporaneous movements on this fault have controlled rates of depositionand thickness of sediments across the fault during Adelaidean and Cainozoic times. Though latest movements of this fault have been west block down, the predominant movement has been east block down with associated thickening of sediments to the east in the Adelaide Geosync1ine.

Jan 1, 1972

The original design of the Bougainville Copper Limited (BCL) concentrator took cognisance of the constraints imposed by the topography, the need to minimise capital cost, and the need to allow for plant expansion which, it was known, would be necessary to maintain copper and gold production as head grades declined.At the same time as spare slots have been taken up with additional equipment, technological innovations have been embraced whenever there appeared to be a chance of improving the productivity ofexisting equipment, or replacing it with a more efficient alternative.There are many examples of this in the BCL concentrator in the areas of process control, process design, instrumentation, materials handling, equipment design and wear part technology.Current process developments also pursue the latest technology. The development of the Omnicone crusher, flotation control, tailings water reclamation, and the variable speed gearless drive on the No. 13 mill are prime examples.

Jan 1, 1986

By G H. Park, Y J. Jun, J H. Park

The carbon solubility of the CaO-Al2O3-FeO-SiO2-MgO slag, the main system formed in the Ruhrstahl-Heraeus (RH) vacuum degasser, was measured at 1873 K to understand the effect of slag compositions on the carbon contamination in the ultra-low carbon (ULC) steels. The stable form of carbon was demonstrated to be carbonate by plotting the log [(wt%C)/aC] ratio against the log p(O2) which ranged -11 < log p(O2,atm) < -9. The carbon solubility of the CaO-Al2O3-FeO-SiO2-MgO slag can be estimated using thermodynamic model. The distribution ratio of carbon increased with increasing concentration of FeO due to the FeO reduction reaction and increased basicity of slag. The carbonate capacity of the CaO-Al2O3-FeO-SiO2-MgO slag can be expressed as a linear function of the activity of lime and the optical basicity.

Jun 19, 2024