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The late 1960's and 1970's saw the initial development of the coal resources of the Bowen Basin of Queensland. The projects developed relied on large scale, open-cut operations using draglines for overburden removal and, in the majority of cases, project viability could be established based solely on those open-cut operations. Many of the mines developed in the 1980's have the same characteristics.Unlike these mines, the German Creek Mine has limited open-cut reserves at low overburden to coal ratios, and planning of the complex involved a large open-cut mine capable of developing early cash flow, with phased introduction of underground mining to replace open-cut capacity as the strip ratio increased.

Jan 1, 1985

An integrated mining equipment development organisation is typified by Deutsche Montsn Technologic of Essen, Germany. working on improvements in reliability, production and control in coal mines. Examples of recent mining advances are in mechanised roadheading, in different approaches to cutting technology, and in low height roof bolting.On the longwall face the mechanics of cutting are related to supplied energy as well as to dust make. In conveying both armoured face conveyors and conveyor belts are monitored. Roof support is not neglected and the continuous pumping of stowage slurries provides further options for longwall support. Surveying developments, particularly the gyro-theodolite, directional drilling. and shaft vehicle monitoring provide further examples of advances in control in coal mining activities.

Jan 1, 1991

By Wallman D

Since 1981 two single entry roadways have been driven at Ellalong Colliery for a total distance of 1 030 metres. They were driven at a height of 1.73 metres within the 3.7 metres thick Greta Seam using a Dosco In-Seam Miner (I.S.M.). Ventilation of the drivage was accomplish- ed by an exhausting fan in series with steel ducting and flexible ducting in the immediate face area. The air quantities provided at the face were more than adequate to comply with the requirements of -the auxiliary fan rules and the Coal Mines Regulation Act, 1912, as amended. The experience gained in these drivages demonstrated that the ventilation of long single entry headings can be practically and safely achieved using existing equipment.

Jan 1, 1983

By Anderson K

In 1991, the first horizontal raise drill hole in Australia was successfully completed by Australian Raise Drilling Pty Ltd (ARD) at the Perseverance nickel mine of Western Mining Corporation's (WMC's) Leinster Nickel Operations in Western Australia. At that time, WMC were experiencing considerable difficulties in developing the horizontal drill drives through the orebody using conventional drill and blast techniques. Following the success of the initial hole, a further two holes were drilled as part of the evaluation program. The technique has proved so successful that it has been accepted by WMC for on-going development of drill drives at Perseverance.This paper describes the program. It relates how the project evolved, the modifications that were required to the equipment used, the performance experienced during the program and the future of the method in this and other applications.

Jan 1, 1993

By Yaroshenko YuG, Bokovikov BA, Gordon YaM

Problems of the effect of the number of tuyeres and their parameters on the uni- formity of gas distribution are invest- igated with the use of the authors' devel- oped mathematical model of the movement of gases and materials in the blast furnace. It is shown that the improvement of uni- formity of gas distribution with an increase in the number of tuyeres has a damping character. An analysis of the errors of the specified assumptions of the hypothesis concerning the potentiality of the gas movement in the bed is carried out. It is established that the potential approach model gives good results with the determination of the discharge of gas and its stress field, but is not useful for the calculation of local velocities of gas in the raceway. The results of trials of calculation investigations of the dynamics of form- ation of the raceway and the voidageòfield in beds of burden materials are presented in the concluding part of the paper.

Jan 1, 1981

By Fejes A. J

The U.S. Bureau of Mines installed surface and subsurface instruments at a mine site in Colorado to monitor and characterize the overburden response to longwall mining. Instrumentation included a time-domain reflectometry (TDR) cable, a multiple-point borehole extensometer (MPBX), vertical- deformation surface monuments, and in-mine pressure cells for monitoring abutment, pillar, and gob loads with respect to the longwall face position. The purpose of the study was to collect data that could be analyzed to correlate the design of the mine layout to the resulting overburden failure response. Determining the extent of caving and fracturing is important in the and and semiarid Western United States because of the possible consequences to the fragile underground hydrologic systems upon which the land owners and users depend. This study is unique from past investigations because the overburden contains massive sandstone members that impose special conditions on the caving process and pressure redistribution above the longwall panels. This paper presents the results of this correlation study.

Jan 1, 1992

By Hochwimmer B, Baxter JL

Heavy minerals are mined from two fossil strandlines on the southern Swan Coastal Plain. The Capel shoreline, 7 km inland, and the Yoganup shoreline, 15 km inland are arcuate, northwest-facing, and remote from the modern coast. Based on foraminiferal and molluscan assemblages, the shorelines are probably of Pliocene age. The Yoganup shoreline is adjacent to the Whicher Scarp, which is cut into the Leederville Formation (Lower Cretaceous) at the southern boundary of the Swan Coastal Plain. Stratigraphic relations and detailed sedimentology have been studied from temporary exposures in the Yoganup Extended and Yoganup North mines, within a strandline complex at 27 m and 18-33 m above sea level respectively. Heavy minerals were deposited in thin, shallowing-upward sequences along a wave-dominated clastic shoreline cut into pre-Cainozoic sediments. Lithofacies units deposited in eolian, foreshore, shoreface and lagoonal environments are the most significant sites of heavy mineral accumulation. The data collected provide a basis for further exploration.

Jan 1, 1986

Whereas traditionally, stable isotope research has been directed towards resource exploration and development, it is finding more frequentapplications in helping to assess the impacts of resource utilization upon ecosystems. Among the many pursuits, two themes are evident:(1) tracing the transport and conversions of pollutants in the environment and(2) better understanding of the interplay among environmental receptors, e.g. food web studies. Stable isotope data are used primarily to identify the presence of pollutants in the environment and with a few exceptions, the consequence of their presence must be assessed by other techniques. Increasing attention has been given to the isotopic composition of humans with many potential applications in areas such as paleodiets, medicine, and criminology. In this brief overview examples are used from the Pacific Rim to illustrate the above concepts. Stable isotope data will undoubtedly play an increasing role in multi-disciplinary research in the Pacific Rim. However, consideration should be given to more effective strategies, e.g. networking, for pursuing large scale problems such as long range circulation of pollutants.

Jan 1, 1990

In 1972, metallurgical testwork on Renison ore indicated a significant proportion of low specific gravity, tin-barren material ideally suited to heavy medium separation (HMS). Further technical and financial studies provided adequate economic justification and in December 1974 the Renison HMS plant was cannissioned. Initial operations were interrupted by the imposition of tin production quotas for three months in 1976; they were also beset with difficulties particularly with regard to mechanical wear. During the first two operating years much develognent work was carried out including installation of a pyrrhotite flotation bank in the medium recovery circuit, investigations into various wear-resistant materials and the use of atanised rather than milled ferro-silicon. By 1977/78 financial year satisfactory performance had been achieved and since then the average floats rejection has been 18.8% of the total ore treated with an associated tin loss of 2.96%. Developnent has nevertheless continued during the last three years, principal modifications being the installation of larger aperture desliming screens and improvements to the overdense cyclone circuit.

Jan 1, 1978

By Shrivastava P, Humphreys M, Guibal D, Deraisme J

Customer requirements concerning the final products of iron mines are extremely stringent. Because of this, there is an ever-increasing need for mine operators to monitor and strictly control the quality of their product. This quality, as measured by the stockpile grade variability, is the result of a very complex process, where natural characteristics (the orebody and its geology) are transformed through the mining technique (open pit, shovel and truck fleet, blending into stockpile). The only way to reproduce and hence to control the variability of such a system, which is composed of several interactive sub-processes, is by simulation. A complete simulation of a Hamersley Iron Pty Ltd (HI) ore deposit has been undertaken to forecast the impact and cost of various mining methods, mining schedules and product stockpile sizes on variability of chemical and physical characteristics of the products. The mining simulation was made on a conditionally simulated orebody. On a range of criteria, the simulation was considered to fulfil the objectives set and was a valuable aid to analysis of product grade variability, operating and capital costs, selection of equipment, mine scheduling and setting of product grade targets.

Jan 1, 1994

By Trois P

A fully instrumented and bench-mounted diamond drilling machine, purpose designed and built, has been used for investigating the effect of aqueous solutions of various chemical compounds when used as drilling fluids. The rocks investigated were andesite, basalt and granite, the chemical compounds were alkylamines, with various hydrocarbon chain lengths, aluminium chloride and dioxane. Rotation speed seems to be one of the major factors affecting the emergence of mechanochemical effects as the results obtained with aluminium chloride clearly indicate. Penetration rate is either unaf- fected or enhanced by the presence of certain compounds, such as aluminium chloride. On the other hand, penetration rate diminishes when the drilling fluid contains dioxane and exhibits an apparently unpredictable behaviour with alkylamine solutions, although it appears that an increase in hydrocarbon chain length usually equates to an increase in penetration 1. Full Professor, Mining and Mineral Dressing Department University of Cagliari - Italy 2. Associate Professor, Mining and Mineral Ikea- sing Department University of Cagliari û Italy rate. Rock texture seems to have a pronounced effect on test repeatability. With hexadecy- lamine acetate solutions in concentrations ranging from 10-5 to 5 .10-4 molò dm 3 and 41.88 radòs-1 rotation speed, 46 % increments in penetration rate of andesite were observed, with respect to water, whereas penetration rate decreased in basalt by as much as 60¦%o when a dioxane solution was used as drilling fluid. An interpretation of the observed effects is proposed in the light of current knowledge of solid state physics and physical Chemistry.

Jan 1, 1992

By Walshe JL, Solomon M

The Emperor vein system lies on the eastern margin of the Tavua volcanic structure. This is of Miocene age and occurs in basalts(the Mba Volcanics) probably underlain at about 2 km by calcite-rich sediments (the Vatukoro Formation). The lodes are generally flatmakes, or steep fault fillings, or complex shatter zones, and consist of quartz and altered wall rock. In areas of open cavities it is possible to establish a paragenesis which involves five quartz stages and two ore mineral stages. The first ore stage contains calaverite, krennerite, sylvanite and native tellurium, the second petzite, hessite and native gold. The quartz stages are thought to have formed slowly (102 years) from boiling solutions of low salinity at temperatures varying with time from about 250¦C to 190¦C. The system was sealed, the temperature gradient near vertical and the mass flux small. The ore mineral stages probably formed relatively rapidly (101years) from boiling solutions at 250¦ to 200¦C when the system was mainly open. Gold deposition was probably largely a result of fall in aH2S due to boiling, the calculated solution concentration falling from a maximum of about 8 ppb at 250¦C to about 8.10-3ppb at 200¦C. Boiling is also probably responsible for an increase in a02 (by loss of H2) and fall in aTe2 (by loss of H2Te). The fluids are thought to have had a large component of meteoric water and to have been heated by plutons in the core of the volcanic structure. Stable isotope data indicate that they derived their carbon from the underlying Vatukoro Formation and their sulphur from sediments. Circulation may have been confined to the outside of the volcanic structure because of the relatively low permeability of the flows, pyroclastics and dykes within it.

Jan 1, 1987

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

By C D. Rose

A review and summary of the results of 120 coal sampling system bias tests is presented. This review supports new methodology using multivariate statistics currently being considered by ISO TC27 SC4. The current difficulties with ISO 13909-8 are explained and the logic behind the current new working draft is discussed in detail. Bias was detected in nearly 36 per cent of tests reviewed, suggesting that much improvement is needed in designing, maintaining and monitoring the performance of sampling systems in order to avoid sampling bias.CITATION:Rose, C D, 2012. Bias testing of mechanical sampling systems for coal - A review of test results and call for use of multivariate statistical analyses, in Proceedings Sampling 2012 , pp 185-192 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 21, 2012

By Hang G, Hongtian X

In this paper, it is briefly introduced that China's Ordovician limestone confined-water menaces coal mining and Ordovician water is prevented and cured to secure the safety of coal mining. The theory of "Down-Three-Zones" is presented on the basis of research and practice in recent ten years. The concept of "Down-Three-Zones" of floor water-eruption is described clearly. Finally, the principle and method of applying the theory of "Down-Three-Zones" are discussed. 1. An Introduction of Damage: China is rich in coal resources. The conditions of coal field geology are quite complicated. There is an area of two million square kilometre of Karst limestone in nine million six thousand square kilometres of territory. The resources of underground water are rather plentiful, but this menaces coal exploration. Sixty percent of coal mines in China are damaged by limestone confined-water in different scales, particularly coal mines located the Carboniferous-Permian coal fields of the Ordovician limestone distribution area of Northern China. Because there is the 500-800 metre thickness of Ordovocian limestone and the well developed Karst containsl plentiful water, Karst water can have more than 100 Kg/cm pressure. Limestone aquifers have only distances of several metres or several decade metres to coal seam, Karst water can enter the aquituge and even the coal seam, large eruptions often occur. For example, a mine of 3 million ton production capacity had an eruption of 2053 cubic metres per minute. This is the largest confined-water eruption which has brought enormous economic damage and threatened the safe production of coal mining. Therefore, the prevention and cure of Ordovician water has immense advantage to the development of the coal industry. There are several decades experience in the prevention of Ordovician water-eruption in China. The prevention of Ordovician water-eruption has two kinds of plans. 1) dewatering and depression: it refers to dewatering of aquifers as roofs of seam and depression of aquifers as floors of seam in mining areas. 2) comprehensive prevention under the condition of having water pressure in aquiters. Due to enormous water, electricity, equipment and lots of other factors, the former isn't used extensively, the latter tits to China's actual conditions and is used widely. So-called comprehensive prevention under the condition of

Jan 1, 1988

By Howarth W. J, Sowerby B. D, Watt J. S

On-line analysis systems have found widespread application in the metalliferous mineral and coal industries. The continuous analysis and rapid response of these systems has led to improved control of mining, processing and blending operations, with increased recovery of valuable minerals and coal combustibles.The paper reviews developments in on-line analysis by CSIRO and Mineral Control Instrumentation Ltd which led to the award of the Australia Prize 1992. These commercialised systems analyse mineral and coal slurries; determine the ash and moisture contents of coal on conveyors, and the moisture content of coke on conveyors; and determine the carbon content of fly ash. These gauges are estimated to have resulted in productivity increases valued at $50 million per year to Australia.

Jan 1, 1993

The performance of the Australian Mining Industry over the past 10 years using key indicators of production, revenue, aftertax return investment, together with key cost elements, market changes and ore reserves is briefly reviewed. The elements of competitiveness are discussed forthe industry and the effects of Government charges and policies relating to existing operations are outlined. There is a demonstrated need for improvements in competitiveness in direct and indirect costs and for improved access to resources for the mining industry to continue to grow and add to Australia's economic growth.

Jan 1, 1987

It is a sad commentary on human nature that for every successful, unscrupulous entrepreneur you need a multitude of incautious, greedy investors. One wonders whether is will be ever possible to completely protect investors from their reckless gambling instincts, which are so widely encouraged elsewhere in society.

Jan 1, 1989

By Clift N

Lead concentrate from the Isa and Hilton lead-zinc concentrators of Mount lsa Mines Limited is smelted at Mount Isa to produce a lead-silver bullion. This bullion is cast into four tonne blocks and shipped to Britannia Refined Metals Co Ltd, NorthDeet, England and to plants in Asia for refining and marketing. The traditional treatment stages at Mount lsa are sintering, smelting, and drossing and casting, with some of the sinter plant feed being pre-treated through an Isasmelt plant.A commercial scale lsasmelt based lead smelter was commissioned in early 1991.

Jan 1, 1993

In the five years since Great Central Mines Limited (GCM) commenced exploration in the Jundee and Bronzewing areas of Western Australia's Yandal greenstone belt, the Company has been transformed from a junior explorer into Australia's fourth largest gold producer with annual production of approximately 440 000 ounces and mineral resources of seven million ounces of gold.The growth in resources has been driven by a high quality geoscientific approach, supported by a substantial budget for drilling and strong management commitment. In 1997, the Company expects to spend US$30 million on exploration in the Yandal greenstone belt.

Jan 1, 1997