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As this Seminar is on "Progress - Mining and the Environment", I am taking the liberty of extending my address beyond the scope implied by the subject, "Rehabilitation of Mined Land", with a preliminary discussion on broader economic issues relevant to "Progress and Mining in Western Australia" before discussing its effect on the Environments Western Australia is nearly one million square miles in area and has a population density of approzimately one person per square mile. Because of its vastness it has wider climatic variations than any other Australian State. The north is tropical and the south is in the temperate zone. The major portion of the State is an arid plateau with less than 10 inches of mean annual rainfall. The climate, rainfall and soil conditions of the South-West region are more favourable to agriculture than any other part of the State and consequently was settled first. The immediate need of the colonists being food and shelter, the early economy was based on farming and forest products.

Jan 1, 1971

The mining industry views with the utmost concern, legislative or administrative action that inherently reduces the scope for exploration activity. Is there any basis for this concern in relation to Victoria? This paper will outline the role of the Department of Minerals and Energy and the main features of legislative provisions affecting exploration effort. The practical difficulties that confront the Department and explorers alike will be examined. The importance of industry representation to influence the direction that policy and legislative review might take, will be highlighted. Above all, the paper will establish that one essential duty of government is to ensure the provision of appropriate mining titles and security of tenure.

Jan 1, 1982

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 Canning RL, Pritchard J

The surface treatment works in the Mount Isa Mines Limited copper stream consist of a concentrator and smelter with annual capacities of 5.6 million tonnes of ore and production of 155 000 tonnes of anode copper respectively. Both plants have been sites for process optimisation in recent years, the emphasis being to achieve productivity gains in each particular plant. The continued low real world prices for copper resulted in an in-depth review of the entire copper process stream. This indicated the need for developments within both the concentrator and smelter, and changes to operating strategy to ensure that the entire treatment stream could be optimised. The paper reviews these changes.

Jan 1, 1986

By Y Tsukurimichi, D Asahina, T Endo, T Takemura

Scientific knowledge of Mars’ surface morphology and internal geological structure has been accumulated through satellite imagery and numerical topographic data using remote sensing technology, as well as seismic surveys by the on-site lander. Recent studies show that Marsquakes could be caused by the release of strain energy generated by the contraction of Mars. In particular, Marsquakes occur around the graben where many faults are existed and formed regularly spaced patterns. This implies that Marsquakes occur when the stress field of the Martian crust is an extension condition, and normal faults appear on the surface. We focus on the linear relationship between the fault spacing and the thickness of the mechanical layer as an approach to studying the internal structure from satellite images. Mechanical layer is a layer that composes of the same mechanical properties and is mainly bounded by lithology (Narr, 1991; Gross, 1993). The linear relationship between the thickness of the mechanical layer and the joint spacing has been studied and its slope is called the Fracture-Spacing Index (FSI) (Narr and Suppe, 1991). Soliva, Benedicto and Maerten (2006) showed that the stress drop zone (stress shadow) due to the fault activities affects the fault spacing. Figure 1 shows the approach used to estimate the thickness of the mechanical layer from the fault spacing on Mars. This paper aims to better understand the internal mechanical structure of Mars estimated by the geometrical pattern of faults on the Martian surface. We report the initial studies of this work. The lab-scale physical experiments and numerical experiments were presented to demonstrate the relationship between the thickness of the mechanical layer and the geometric pattern of fractures

Nov 29, 2022

By G R. Hancock

A common and cost-effective method for post-mining landscapes is to construct linear hillslopes with a break in the hillslope at appropriate distances to reduce hillslope length and resultant erosion risk (Figure 1). The break in slope occurs at a point that has been found by local experience to be appropriate for the materials and climate. Further enhancement of the linear hillslope may be assisted by surface treatment such as ripping (Saynor, Lowry and Boyden, 2019) (Figure 1). Firstly, ripping introduces surface roughness which breaks up flow paths reducing flow velocity thereby reducing erosion potential. The depression produced by the ripping acts as a trap which captures water, sediment and organic matter

Aug 2, 2023

Felspar occurs in association with quartz in the Broken Hill lode pegmatites and is brilliant green, greenish white, and white in colour. The pegmatites occur mainly in the walls in sporadic patches, parallel to the general dip of the ore deposit. The occurrences are of no economic value.Deposits of marketable felspar occur in pegmatite in a number of localities around Broken Hill, New South Wales.The majority of these are in the form of an irregular outcrop, usually of tapering length and depth. The maximum depth of any deposit yet worked in the district is about 40 ft. The felspar is occasionally contaminated by "blows" of quartz, mica and beryl, but the two latter are profitably marketable when separated.Felspars vary in colour from pink, through grey to snow white, and the colour is not indicative of the mineral content. The largest deposit at present being worked is the Egebeck quarry, about 14 miles south of Cockburn. It is a prominent outcrop, roughly circular and about 150 ft. in diameter, covered by one to three feet of overburden.The felspar is mainly massive, but contains some cleavage planes at approximately 90°. Intrusions of quartz and mica occur in patches, but the deposit appears likely to improve in size, regularity and quality below the present working floor.COMMERCIAL USES.Commercial felspars are mainly used in the ceramic industry, for which a high-grade potash felspar is required.The dental industry requires limited amounts of soda felspar with a very low Fe20s content. The poorer grades...

Jan 1, 1946

By Tomlinson R. C

The paper will briefly describe planning in the National Coal Board (NCB) and the contribution that operational research makes to it. It will then give details of some of the models in use and will finally consider critically the problems of looking ahead to the next century.

Jan 1, 1977

The last decade has seen a dramatic change in the. size and complexity of mining and mineral processing projects in Austral- asia. Major projects of today are vastly different from major projects of the 19.50's. This change has in turn resulted in a change in the role-of consultants whose contributions have been increasingly in the provision of specialist services and less in the form of overall project design and construction supervision. It is anticipated that, the specialist function will continue to represent the principle mode for consultant participation in major, projects. However, by means' of international affiliation, the development of comprehensive engineering and project management capabilities and possibly as a result of Government intervention, it is expected ,that local consultants will assume an increasing degree of participation in.the overall project design and supervision Function.

Jan 1, 1975

This paper deals with the evolution of present mechanised declining and orebody development practices at Kambalda, since their inception in 1969. Eight separate decline accesses have been established over the past eighteen years and to date some 175 kilometres of declining and lateral development has been achieved utilizing a wide range of mechanised development and mucking units. Improvements in-the range of equipment available, functionalization of the develop- ment tasks and the resultant changes to piecework contract structuring have all contributed to the improved performances achieved in this concept of mine development. Even though numerous development advance rate records have been established at Kambalda, an ongoing evaluation of changes to both drilling and mucking units is underway to further improve these development performance rates.

Jan 1, 1987

By Craw D

The Southern Alps in the South Island of New Zealand are currently rising rapidly as a consequence of continental collision along the Pacific-Australian plate boundary. Rapid uplift has resulted in a major thermal anomaly in the shallow crust beneath the alps. Alpine topography and associated intense precipitation, coupled with the thermal anomaly are responsible for vigorous combined topographic/convective circulation of water through the shallow crust.

Jan 1, 1995

Electronic Detonators have made significant strides over the last few years, both in quality of product and performance in different blast applications. The precision and flexibility of the SMARTDET units provides the mines with a powerful means of controlling blast results, giving both cost and productivity improvements. The SMARTDET Electronic Detonator System, robust and easy to use, has been successfully deployed over the last 18 months in improving mine productivity and creating safer working conditions in both quarrying and long-hole stoping. The key to the improvements has been the precision and flexibility of the electronic timing, and the ability of the mine personnel to grasp the concept quickly and use it effectively.

Jan 1, 1999

This paper discusses design concepts in planning a large modern bulk terminal. The need is emphasised for a studied master plan, in-built materials handling flexibility and staged development. An integrated approach is advocated, combining functional purpose designed foundations and structures to serve their mechanical, electrical and environmental functions. Dry bulk and slurry handling are also compared in perspective.

Jan 1, 1983

By Wu H. W, Jones S. J

Australia wide, over 40 fly-in/fly-out mining operations and other forms of long distance commuting now exist, with coverage of about 5000 employees. The substantial majority of these operations are in Western Australia, with some mines also located in Queensland and the Northern Territory. In recent years new large-scale mining operations have adopted the fly-in/fly-out approach and it is important to note that no new mining towns have been constructed in Australia since the township of Roxby Downs was built in the late-1980s to service the Olympic Dam mine. An examination of fly-in/fly-out mining operations in Australia has been undertaken. A detailed survey undertaken in 1990 has been reviewed and another intensive survey undertaken to establish emerging trends. Results from both company and individual employees point of view have been analysed. A section examines the views of professional employees and the influence of fly-in/fly-out on career development. Bus-in/bus-out coal mining operations are emerging in Queensland's Bowen Basin. These operations commute their employees into the mine site for compressed working schedules while the mine employees' families are domiciled in regional cities such as Mackay. A review of the issues associated with the development of long distance commute coal mining operations in Queensland's Bowen Basin is performed and two case studies examined.

Jan 1, 1997

With the continued drop in export coal prices (as measured in US$) delivered to the Pacific Rim market, and a fixed annual 12 per cent increase in overburden, Usibelli Coal Mine Inc was faced with the need to reduce mining costs substantially or else forfeit its foreign coal contractual commitment which amounted to about half of annual mine output. Management made a difficult and fortuitous decision to proceed with an engineered plan to switch from a two seam, extended bench dragline operation to a two seam, cast blast and spoil side operation. While down-sizing and cut-backs became the rule in all departments of the mine, the drilling and blasting budget was more than doubled. Most will agree that this is contrary to what usually happens when a mine is faced with down sizing. The more common scenario would have management target the drilling and blasting budget for decrease as a first priority to cutting cost, and then later witness a decrease in equipment performance leading to an increase in the production cost per tonne. Although Usibelli Coal Mine more than doubled its annual drilling an blasting budget three years ago, the overall stripping cost has be, reduced by more then 37 per cent.

Jan 1, 1995

By M Khanal, J Qin, B Shen, Y Duan, X Luo

Gaining confidence in interpreting rock and strata properties of the coalmine roof is necessary for design, maintenance, modelling and optimisation of roadways supports. One of the key causes of roadway instabilities experienced in underground coalmines is an extreme variable nature (thickness, competence, discontinuities etc) of the coalmine roof. Normally, the thickness and strength of the roof are characterised with the geotechnical and geological data gathered from exploration boreholes, which are drilled often at considerable distances apart. This limited data cannot capture localised geological variations in the coalmine roof. With this background, this paper explores feasibility of using measurement while drilling concept to perform geotechnical characterisation of the coalmine roof. The parameters, for example, penetration rate, rotary speed, torque, sound, vibration, obtained during the drilling process can provide valuable insights into geotechnical properties. The paper describes the progress of the experimental work conducted at the laboratory on synthesized concrete samples representing various rock strata using a field-scale drilling machine. The samples with and without interfaces have been tested to replicate various underground roof strata. The signals returned from the drill machine, as the drill bit passes through the layers, have been analysed and interpreted to characterise whether the drill response data can differentiate various strengths associated with the rock layers. The initial laboratory results are promising as they show distinct responses of the various sample blocks in a controlled environment. The drilling data can differentiate the synthesized rock samples and detect ‘signatures’ of the roof strength variability and delineation of lithological interfaces (transitions). The weight and torque on the bit vary and show dependency on the strength of the blocks.

Nov 29, 2022

By D Liang, L Zhang, X He

The sulfurisation-flotation process was unsuccessful when initially applied to the oxidised Pb-Zn ore in Lanping County of Yunnan Province China. A comprehensive mineralogical study indicates that the problem is caused by the soluble salt gypsum in the Lanping oxidised ore, which produces a large amount of Ca2+ cations. The Ca2+ cations react with S2- anions (from sodium sulfide) in preference to Zn2+ and Pb2+ forming calcium sulfide, and make it difficult to form zinc and lead sulfides on the surfaces of the respective oxidised Zn and Pb minerals. In addition, the calcium sulfide formation consumes a large quantity of the available sodium sulfide, further inhibiting the sulfurisation process. The efficiency of the sulfurisation of oxidised Zn and Pb minerals has been improved greatly by the pretreatment removal of gypsum, with the added benefit of the required dosage of sodium sulfide being substantially reduced.

Jan 1, 2008

By B Wiggins, M Russell

Off-gas handling systems are a critical component of modern metallurgical furnaces and typically represent as much as 50 per cent of the total installed smelter capital cost. Inadequate off-gas system performance, due to insufficient exhaust flow or excess maintenance downtime, can present a serious process bottleneck and limit smelter production rate. Therefore, it is essential that the relevant performance issues are fully understood and considered in the design of these systems, particularly when combustibles produced within the furnace must be combusted or handled in the off-gas system. This paper examines the requirements, design issues, and conceptual design process for state-of-the-art postcombustion off-gas systems. The relevant design considerations of safety, environment, energy consumption, and maintenance are presented, and the relative importance of these key issues are compared and discussed. The benefits of using computational fluid dynamic (CFD) modeling in the design process at the conceptual design stage are also demonstrated. Finally, the design basis and performance of a recent Hatch-engineered system currently in operation is evaluated.

Jan 1, 2002

By Hongzhen Yu, Xiaoping Ma, Jiansheng Qian

The paper introduces the design of an Intelligent Managerial Attendance Machine (IMAM) for coal mines. In the system, data communication is carried by Optical fiber communication, including industrial control computer on the ground and the car

Jan 1, 1998

By Fabjanczyk M. W

The design of underground mine roadways (tunnels) requires a detailed understanding of the in situ stressfield, the rock failure modes, the performance characteristics of reinforcement or support members and assessment of the stress state about the roadway. Definition of these factors, together with monitoring of roadway behaviour during both development and extraction operations, allows rational design procedures to be undertaken.The design approach utilised computational techniques to simulate the behaviour of the strata about the opening for a range of anticipated stressfields and various reinforcement options. Field validation studies are conducted to confirm the design expectations.

Jan 1, 1993