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Although the mining of metals was well established by the time of the Roman Empire mining skills did not really advance greatly for many centuries. Miners did not have the scientific knowledge to distinguish minerals, to process them, and to obtain the best recovery. Each mine essentially developed its own methods in isolation, most of them dangerous. However, with the beginning of the industrial revolution in the early 18th century there was a rapid increase in mining activity in Central and Western Europe and an accompanying need to educate professionals in the developing fields of science and technology. There was also a need for specialised schools (for example, Schools of Mines) to accomplish this since the universities of the time, formed as early as the first half of the 12th century, were cloistered institutions, focused on the study of classics, theology and law. The earliest attempts at organised technical education were made in 1702 with the establishment of a School of Mines in Frieberg, Germany (Table 1) to service rich copper mines, and in 1747 with the establishment of a School of Mines in Paris. By this time, the industrial revolution was well under way and other Schools rapidly followed, at Clausthal in the Ruhr region of Germany in 1775; in 1777 at Almanden to service the mercury mines of Spain (later transferred to Madrid); in 1780 at St Petersburg, Russia and at Falun, Sweden in 1819. The academic staff for these new institutions were often trained in the original School at Frieberg.

Jan 1, 2002

By V Yadi

Geostatistics has been widely used for more than four decades as a powerful tool in ore resource/reserve estimates and grade control. This method has gradually replaced the conventional method such as polygon and cross-section for grade estimation by more mathematical techniques such as kriging. The advances in geostatistical understanding and the availability of appropriate software packages have given much more contribution in speed and high accuracy during production. However, in many cases, these techniques are sometime applied without support with a good thorough understanding of the geological controls on metal distribution. To produce the result close to actual, the geological control in interpretation and appropriate geostatistical task is a must. Geological logging was described in the core must be consistent with the level plan produced by commercial modelling software used as a guide for grade control during production. Experience gained through evaluation of the Central I deposit resulted that the most effective systems continue to be based on geostatistical methods of resource estimation. Computer applications modelling software packages are necessarily as the core of an efficient in undertaking these assignments. They contribute to make a valued to data management and are becoming increasingly effective during processing. The latter role is particularly important to check the actual versus estimated values where will significantly to improve personnel to have a confident with their knowledge combined with experience and complete their jobs satisfy.

Aug 22, 2011

By H Benzer, N A. Aydogan

It is well known that the high pressure grinding rolls (HPGR) can only be operated efficiently under choke feeding conditions in which a material bed is built up between the rollers to ensure interparticle breakage. By increasing the fines amount in the material bed up to a specific level with the recycling load, a uniform material bed is created and higher pressure gradient along the roller width is obtained which results in compact flakes including more fines. Extensive test work has been carried out with an industrial HPGR unit grinding cement clinker in a cement plant in Turkey. During the test work the recycling load of the circuit was changed to achieve different ratios to the fresh feed rate in order to identify the effect of the recycling load on the circuit performance. Six different tests were performed with the circuit at steady state. For each test, samples were collected from HPGR fresh feed and discharge, and total feed, then the particle size distributions of the samples were determined and mass balances around the circuit were calculated. The conclusion was that the reduction ratio of the HPGR increased with increase in recycling load. The flake densities showed the same trend with more compacted flakes being produced for higher recycling loads.

Jan 1, 2009

By Bedford D. J

The post pillar cut and fill stoping method has been adopted by King Island Scheelite for the extraction of the main Dolphin orebody. The orebody is a massive, tabular deposit varying from 10 to 50 metres in thickness, and dipping at approximately 30¦ towards and under the sea bed. The mining method was selected for 1. maintenance of hangingwall support under the sea bed; 2. maximisation of first stage ore extraction; 3. flexibility of mining, allowing maintenance of grade and selective mining around waste bands within the orebody, and 4. compatibility of existing equipment both with stoping and the on-going underground mine development programme. Stope parameters were established on the basis of initial rock stress analyses, and since the undercut phase of mining the stoping programme has been monitored with various types of deformation measuring devices installed in a series of large diameter boreholes.

Jan 1, 1977

By Shillabeer J

Paste backfill has been adopted by many underground mines in North America and a growing number elsewhere. Paste offers a number of advantages. This paper suggests wider applications of paste technology to surface tailings disposal and water management. Advantages include improved overall stability, potentially easier permitting, smaller water inventory and earlier reclamation. It may be feasible to use the same plant to prepare backfill and to dispose of surplus tailings. Example cost models are given to illustrate potential applications.

Jan 1, 1998

By A B. Christie, R Barker

Recent studies carried out to support the development of a strategy for the New Zealand mineral industry by the NZ Minerals Industry Association have included investigations of mineral potential, and the development of scenarios for realising this countryÆs mineral potential by 2010. New economic research is applying a general equilibrium model to quantify the opportunity cost of this potential. The model analyses separately four categories of land (private land and three categories of Crown land) and identifies four distinct mineral classes û precious metals, industrial minerals, coal and aggregate. It investigates the economic effect of the increased availability of mineral resources on the mining industry itself, on other industry sectors and on the NZ economy generally, including its impact on unemployment, GDP and household welfare.The analyses suggest that increases in the level of GDP of between 1.9 per cent and 3.4 per cent may be obtained by utilising New ZealandÆs mineral wealth to varying degrees. The mineral industry sectors are significant beneficiaries under all scenarios; mineral output increases by between two and five times its current level. However, the flow-on effects to the rest of the economy, and to households, are also significant. The analyses show that household income, adjusted for changes in consumer prices, can be expected to increase by between 1.6 per cent and 2.7 per cent. This results largely from increased employment.

Jan 1, 2002

Underground measurements, observations and computed simulations, started a long time ago were concerning the study of : - occurence of typical rockburst, - inducing, stretching of main fractures in the roof of caved longwalls. They made obvious a foundamental phenomenon of inducing of strata fractures involving contact be- tween two layers quite different in their elastic characteristics : coalseam and rocklayer.. The start of primary cracks in maximum abutment zone takes place in the rock near the contact surface. It is opening of crevasses induced by traction stress component resulting of difference of rigidity of both materials and no sliding on in- terface. Occurence and stretching of these crevas- ses are a rheological phenomenon so that the rate of advance and stops of the face influence the distance between the crevasses and the stretching of these ones. The characteristics of these cracks in space and time affect mining conditions. So it is for fractures proximity and expan- sion inducing eventual blocks formation in longwall roofs in front of faces, for depth and delay of road- ways ribsides fracturing, inducing some rockbursts. In longwalls roofs, cracks initiated in front of a face can be either quite close or quite distant each from the other one, according to the depth of crushed coal in front of the face, which af- fects also extension of the cracks.

Jan 1, 1988

By Quilliam B, Richmond G

Aberfoyle Ltd. has utilised a variety of flotation technologies in the Hellyer concentrator in North-Western Tasmania. Hellyer ore, with its slow flotation rates and low rate differentials between values and gangue, requires the use of long residence times and low air consumption rates in the flotation circuit. The operation of the flotation circuit, with a nominal residence time of 7 hours, has necessitated the development of a control system to provide continuity through operator shift changes. Cell selections at Hellyer varied from the 54 m3 hybrid Dorf Oliver / Maxwell (DO/MX) cells, to smaller 32 m3 Maxwell cells, conventional Don-Oliver 300 (8.5 m3) and 600 (17 m3) trough cells, and a column cell. The advantages of the large cells included low specific power consumptions and a low capital cost. However, problems with mixing and the maintenance of consistent froth depth have been identified in the hybrid DO/MX cells. Short circuiting in the trough cells was apparent, causing a considerable reduction in metallurgical performance. The column cell performs to expectation, although the application is not ideal.

Jan 1, 1991

Synthetic seismograms of reflectivity method and some field records available are studied to detect the amplitude anomalies at the interface of the gaothermal reservoir the gas and/or oil boundary, and the underground tunnel. The first arrival of PO wave on the P-SV record are weak and emergent while those of P wave only rotated with respect to an incident angle are clear. This can, be explained by means of the energy loss of P-SV wave conversion. The primary reflections of P waves about depth fade away as compared to SH waves which do not perform any conversion, although they hold high attenuation in the fully saturated fluid layers. Reflection of comparable strength is present at the P-wave and S-wave... boundaries, but gas-saturated zones correlating with P wave bright spots do not show equivalent attenuation anomalies. Thus the comparative technique of P-SV wave and SI i wave records is very useful to indicate the strong amplitude anomalies at the boundaries of sealing targets.

Jan 1, 1990

By M Alston

Many organisations struggle to yield meaningful outcomes from incident investigations. This paper will demonstrate that we can discover systemic issues by rethinking the ‘Why’ and ‘How’ of investigations, fostering genuine risk reduction. Key points: 1. Shift from ‘prevent recurrence’ to ‘learn and reduce risk’: conventional investigations focus narrowly on recurrence prevention, resulting in narrowly focused investigations with limited ability to identify and reduce organisational risk. Redirecting our objective to learning and improvement opens avenues for broader risk mitigation. 2. Understanding daily work for risk insights: recognise that work is not always completed in full compliance with procedures. Workers will adapt how they complete tasks influenced by the conditions and management systems that exist every day. Understanding the conditions and systems affecting everyday work is vital for uncovering systemic risks. 3. Unearth systemic issues through in-depth exploration: many investigations address surface concerns such as lack of training, incorrect procedures, equipment not being maintained, and missing overarching organisational risks. Systemic, organisation-wide risks are not identified. To discover these systemic issues and create shared learnings, investigators must question management systems, including resourcing, planning and risk management. 4. Design actions for safe failure: common actions like discipline and training fall short and do not reduce risk. Resilience emerges from well-designed controls. Incorporate planning, better resources, interlocks, and guarding to bridge the gap between task execution and risk. 5. Investigation Reports as a Business Case: Investigation reports should not simply state historical information regarding an incident. They are to facilitate decision-making and be presented as a business case to drive change. Organisations can move beyond localised risk and ineffective administrative actions by changing investigation objectives and methods. They can facilitate learning, understand daily work intricacies, identify systemic issues, and enhance the capacity for safety, driving lasting risk reduction.

Apr 16, 2024

By P Commander

Western Australia is a major exporter of minerals, which places significant economic and environmental responsibility on Government and the stateÆs mining industry. Moving into the 21st century, mineral production in Western Australia is $14 billion accounting for 50 per cent of the stateÆs export income. There are over 60 large-scale mining operations distributed throughout the arid regions of the state (less than 300 mm/year rainfall). There are four key mineral provinces in arid Western Australia including the Pilbara (iron ore), Murchison (gold), Northern and Southern Goldfields (gold and nickel). These provinces have significant differences, particularly in respect to groundwater demand from mining and mineral processing, aquifer systems that are utilised, and approaches to groundwater management. The arid nature of the stateÆs interior and subsequent lack of surface water resources has required substantial groundwater resource development by the mining industry. A variety of aquifers have been explored and utilised ranging from shallow alluvium and calcrete, discrete fractured zones in bedrock, concealed palaeochannels and inland sedimentary basins. Groundwater usage by the mining industry is about 150 GL/year with most abstraction related to mine dewatering, mineral processing and dust suppression. Groundwater abstraction in Western Australia is regulated by the Water and Rivers Commission. In the Goldfields, the depletion of brackish (>2000 mg/L) and saline groundwater from storage is permissible, as mining is considered the beneficial use for groundwater which may be as much as 200 000 mg/L. In contrast, the low salinity groundwater of the Murchison and Pilbara is allocated on a sustainable basis. The role of monitoring and ongoing aquifer reassessment is crucial in water management, in evaluating the condition and performance of stressed aquifer systems. Mining operations face a variety of water resource issues ranging from insufficient availability for processing to excessive mine dewatering. These issues also change as a mine operation proceeds through its development, commonly starting with a deficiency and moving into surplus as deeper pits require more dewatering. Operating mines have to contend with three main issues: water supply, wastewater disposal and contamination of local water resources. In contrast, post closure issues are related to aquifer recovery or re-establishment of groundwater equilibrium, development of pit lakes in mine voids and isolation of waste products and associated seepage or run-off.

Jan 1, 2003

Underground mining in the West Moreton coal field started in the 1870's. Subsidence related to coal mining activities is an ongoing problem facing planners and developers in the Ipswich area in South Eastern Queensland. The history of coal mining in the area over the last 110 years has left the legacy of periodic surface instability in several areas. In general, modern engineering analysis with current mining methods combine to create predicatable analysis of surface stability and movement. Where old workings using several variations of the bord and pillar system are affected by current activity, the predictibility of the surface movement is greatly reduced. Geological complexities further complicate the analysis. Mining and the related dewatering affects the stresses on pillars in old workings. This is caused by reducing buoyancy effects caused by changes in the water levels in old workings. Of particular relevance is the depth of workings and strength of the coal and overburden. The type of subsidence affecting the surface can range from localised pillar failure, to roof failure and potholing and the likelihood of the particular form of subsidence can be assessed from studying the workings in relation to the stratigraphy and structure of the coal measure Formations.

Jan 1, 1988

About 74% of global seismic energy release occurs in the Circum-Pacific zone. Worldwide, about 71% of seismic energy release is in the form of shallow earthquakes, 27% as intermediate, and 2% as deep earthquakes. Seismic energy release is variable in time and has been shown to correlate with the amplitude of the Chandler wobble. It was high during the period 1949 to 1967, and is now at a rather low level, with the latest earthquake over M = 8.0 having taken place in Indonesia in 1971. The average worldwide recurrence rate for the expected largest magnitude earthquake (M "9.5) has been estimated as several tens of years, in marked contrast to the several tens of thousands to hundreds of thousands of years separating the largest volcanic eruptions. Geological studies are needed to establish reliable mean intervals between large earthquakes, and to detect the e;:istence of long-term fluctuations in the ste of occurrence. Seismic gaps have proved seful in static forecasting of large earthquakes, by identifying places where closer study of the variation with time of seismicity, deformation, and other parameters, may lead to the dynamic p_ediction of time, place and magnitude of earthquakes. The model of stress concentration at asperities explains the main features of seismicity in the Circum-Pacific. Slow earthquakes have been detected instrumentally, notably an event immediately preceding the 22 May 1960 Chile earthquake, the largest this century. It seems likely that this type of deformation may explain both instrumentally detected and macroscopically observed pre-seismic deformation, as well as unusual animal behaviour reported before some earthquakes. Seismic and volcanic events are interdependent, with large earthquakes commonly triggering eruptions. Melting of rock and intrusion of magma is likely to accompany many earthquakes.

Jan 1, 1987

By B Whiteley, B Gee

The Northside Storage Tunnel is a TBM driven rock tunnel system designed to collect and store sewage from four major storm overflow points along the existing Northern Suburbs Ocean Outfall Sewer. At present, sewage overflows during wet weather are the main source of pollution for Sydney Harbour. The tunnel system comprises a 16 km long by 3.8 m to 6.5 m diameter tunnel from Lane Cove to the North Head Sewage Treatment Plant and a 4 km long by 6.3 m diameter branch tunnel from West Chatswood. The tunnel will have a typical rock cover of about 50 m to 150 m. Most of the tunnel alignment is contained within the Hawkesbury Sandstone Formation which is generally an excellent tunnelling stratum, and offers few geotechnical constraints. However, the tunnel is required to pass beneath incised palaeochannels at Middle Harbour and Manly with each palaeochannel containing about 70 m of sediment.Innovative geotechnical and geophysical investigations were undertaken to examine the tunnel route and characterise the rock beneath the palaeochannels. These investigations have located zones of poor quality rock beneath one palaeochannel in particular, suggesting significant stress relief had taken place in the rock at times of lower sealevel producing structural features indicative of valley bulging. This paper presents the geotechnical model developed for the tunnel, and the models and constraints for tunnelling beneath the palaeochannels.

Jan 1, 1999

The 250 metric tonnes of gold and 360 000 metric tonnes of copper recovered from the Mt Morgan Mine in Central Queensland justify its fame. The mine ceased operation before the advent of three-dimensional computer graphical modelling of orebodies became common practice in mine planning. The Mount Morgan Mine records however remain and are the database for this study. The Mount Morgan project takes ore deposit modelling one step further by examining the relationship between grade distribution within the orebody and key geological features, as a tool for exploration and development.The Mount Morgan gold and copper mineralisation is shown to be strongly lognormally distributed. The deposit has been split into three areas, using geological boundaries, each with different geostatistical characteristics. Important features include: the spatial relationship of near-vertical, high grade shoots with a ring dyke thought to be related to the North Dyke; separation of the high grade eastern stopes from the others along the Andesite Dyke; and lack of concentrated mineralisation along the Slide Fault.Recognition of these features is useful to those currently exploring the Mount Morgan district for similar style deposits, by stressing the importance, or lack thereof, of the geological features.

Jan 1, 1993

There are many factors influencing the way in which a mining company disposes of tailings. Some of the more important factors include physical and chemical properties of tailings, cost, availability of dam wall construction materials, type of mining operation, topography and environmental constraints. As a result, the mining industry has seen a diverse and innovative range of disposal methods developed to satisfy the many conditions imposed at tailings disposal sites. This paper discusses a range of tailings disposal methods currently practiced in the mining industries in North America. These methods include various inpit disposal techniques, upstream, downstream and centreline dam construction and zoned earthfill or rockfill embankment construction. The thickened tailings disposal method and the disposal of fine clays are discussed. The importance of improving the depositional properties of tailings to enhance storage capacity, water reclaim, dam wall stability and final reclamation is stressed. It is important that mining companies are made aware of the full range of disposal methods and dam construction techniques available today. Such an awareness will help improve the planning, design and construction of safer and more efficient tailings disposal facilities in the future.

Jan 1, 1989

By P Gnnther, A M. van Niekerk

Coal mining operations in the Upper Olifants River Catchment in the Mpumalanga Province of South Africa are challenged with the increasing production of excess mine water that cannot be fully managed by existing practices of pollution control at source, recycling, and reuse on mining sites, storage and limited release to the natural water course. In contrast to this, the Olifants River Catchment is experiencing water stress and insufficient water is available to satisfy all water quantity and quality requirements for future industrial and municipal growth. It is estimated that the catchment has a deficit of 192 million m3 per annum if the reserve water requirements are taken into account. The future increased water requirements can be met by water transferred to the Olifants River Catchment from adjacent catchments. The cost of transferred water is likely to be substantially higher than the current cost of water supplied to local municipalities, commerce and industry. BHP Billiton and Anglo Coal Corporation are working together to jointly implement water management strategies that will contribute to the achievement of in-stream and dam water quality and aquatic objectives for the catchment. Consideration is now being given to the treatment and beneficial use of excess mine water. This will inaugurate a new era for the coal mining industry in South Africa, in which a pollution threat to the water resources in the Upper Olifants River Catchment is converted into a water source for beneficial use. Three potential mine water reclamation and reuse schemes have been identified and this paper details the technical, institutional, legal and financial considerations in the implementation of these schemes.

Jan 1, 2006

By P B. Hills, R J. Walton

Narrow vein tabular orebodies are prone to mining induced seismicity. The Tasmania Mine is a complex example of a seismically active tabular orebody, where the contrasting material properties of the host strata and of the orebody itself, serve to exacerbate the seismic response. Analysis of a continuous record of seismicity over a period of seven years has provided significant insight into the fundamental mechanics of the rock mass. Understanding seismicity to permit safe extraction of the orebody has been enhanced by instrumentation of rock mass behaviour in response to mining and mining induced seismicity. It is the purpose of this paper to explore that understanding in respect to the adoption of an alternative down-hole Avoca stoping method for use in particular circumstances.Intensive instrumentation of the Tasmania Mine over a period of four years has provided insight into the behaviour of the rock mass in response to extraction of the narrow vein orebody it encompasses. A range of instruments have been installed in clusters or single installations in order to measure changing stress conditions and the impact of those changes on the rock mass and the reinforcement system.Instruments are often installed in very close proximity to active production stoping. While it has been possible to observe the impact of the mining and mining induced seismicity at very close quarters, instruments installed in these locations are vulnerable to damage and consequently, the level of instrumentation is high. Instruments are continuously logged, typically on a six hourly basis coinciding with the end of regular blasting times. The response of the instrumentation to changed rock mass conditions is considered against the background of development and production blasting and against the seismic record to assess the viability of downhole Avoca stoping.CITATION:Hills, P B and Walton, R J, 2012. Continued observations of rock mass behaviour in response to stoping at the Tasmania mine, Beaconsfield, Tasmania, in Proceedings Narrow Vein Mining 2012 , pp 169-178 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Mar 26, 2012

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

The results expected from a longwall face can best be estimated from the ideal production rate, determined by the capacity of the equipment and the conditions in which it is installed, the effective operating hours, and the utilisation.The effective operating hours are determined by a number of scheduling factors which include the proportion of manned time to calendar time, the effective shift factor (effective time to manned time) and the move times.Analysis of the results achieved on the last 121 completed longwall panels in Australia (1984 onwards) shows a significant trend between 'actual tonnes/manned hour' and 'ideal production rate' (the measure of the capacity of the installation).Using 1982 'state of the art' longwall equipment, (the average in use in the seven year period), it should be possible to produce around 2.7M tonne/year ROM from a mine with one longwall. Few mines are achieving this.A review of production scheduling factors and general natural hazards affecting some mines suggests three things.1. Whilst some increase in average effective hours has followed the CIT decision, further improvement is possible at many installations.2. Many mines subject to general natural hazards, such as high gas make and high general stress, have found effective solutions and achieve the same utilisation as the overall average.3. A small number of faces within such mines have been severely affected, some less so. The most severe effects of natural hazards appear to be very site specific. This emphasises the need for detailed investigation of the causes, and development of means of predicting their presence. Only then can either satisfactory technical solutions be found to overcome the problems or prior decisions be chosen not to mine badly affected panels.

Jan 1, 1991