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By Gray J, Krouse HR, Changkakoti A, Morton RD

A group of stratabound-stratiform Fe-Ba-Zn-Pb-Ag deposits within the La Minita mining district of Michoacan, southwest Mexico have been investigated. The results of the study show that these deposits were generated around submarine hot-springs issuing in a Cretaceous island-arc environment. The exhalative mineralization, which is both epigenetic and syngenetic in character, was developed above fault-systems which constituted the loci of both volcanism and subsequent hydrothermal systems.Fluid inclusion data suggest two hydrothermal events during ore mineralization, one at 240¦C and the other at 161 to 205¦C, with salinities between 2.1 and 12.8 wt.% NaCl equivalent. Stable isotope data support a marine origin for the ore-fluids, as well as, for carbon and sulfur. Strontium isotope data suggest that Sr in the barites was extracted from the volcanics and limestones by circulating seawater. The ore-depositional environment was one of shallow, sub-tropical marine character, where mineralization was in part geochemically controlled by carbonate reefal facies within the volcanic/pyroclastic suite.

Jan 1, 1990

This paper examines the reform of mining legislation over recent years, the establishment of new Crown land management agencies, and the role of the Crown and environmental groups in nature conservation in New Zealand. It describes the relationship of the minerals industry to the Department of Conservation and environmental groups over recent years, and the prospects for mineral development on the Conservation Estate in future.

Jan 1, 1995

By S M. J Koleini, F Hedjazi

The purpose of this research was to study the calcination of lead-zinc flotation tailings from the Angouran lead and zinc flotation plant in Iran as a pre-concentration step prior to hydrometallurgical processing of the oxidised tailings. There is an abundance of these tailings in the Angouran region and making use of these tailings would help preserve national wealth and also reduce the serious problems of environmental pollution caused by the tailings. At the optimal conditions of calcining at 750 - 800¦C for 45 minutes, the sample showed a mass loss of about 19 per cent. Mineralogical analyses showed that under these conditions the carbonate minerals including smithsonite (ZnCO3), calcite (CaCO3) and dolomite (Ca Mg (CO3)2) decomposed to their respective oxides. Hemimorphite (Zn4Si2O7 (OH)2.H2O) converted into willemite (Zn2SiO4) and this transformation postponed the formation of silica gel in the leach solution. The grade of zinc increased from 22.20 per cent to 29 per cent. These mineralogical changes resulted in desirable reactions in the acid leach process.

Jan 1, 2004

By S Pollak, A Amon

This paper describes the current and finished design work which has been performed for shallow rock station caverns for New York CityÆs first new subway construction in 60 years. A new robust, sophisticated, design procedure has been developed for two up to 30 m wide caverns, with overburden of less then 12 m, and rock cover to span ratios (C/S) in the order of 0.25. The design is based on empirical input parameters like the Q-value, rock mass rating (RMR) values, rock mass class after Cording (1984), cover to span ratios, which have been validated by the use of structural computer models as well as two- and three-dimensional numerical discontinuum models. The design approach is a staged approach using first principles, empirical models and non-linear FEM and DEM models. In addition, the paper describes the factors and circumstances why shallow caverns have been selected instead of cut-and-cover structures and why all the underground station structures have been developed as drained structures.

Jan 1, 2008

By J Kwiri, T Zvarivadza, R Mitra, F Cawood

It is crucial to record ground movement of any magnitude to enable the safe and economical design of excavations and infrastructure. The DigiMine Laboratory is equipped with technologies to record such movements. This paper analyses the effectiveness of the Digital Mine instrumentation in recording earth movements in light of the Botswanan earthquake which occurred on the 3rd of April 2017 at 17:40 UTC. Recordings from the Digital Mine are compared with other ground sensing technologies which also captured the event (USGS and GEOFON systems). USGS and GEOFON system’s recordings suggest that, there are a number of possible mechanisms that could have resulted in the earthquake as discussed in the paper. Compared to the USGS and GEOFON systems, DigiMine system could not provide an analysis that could give possible source mechanisms. However, the system’s success in recording the Botswanan earthquake, is an indication that the system works and can be further developed or improved. For a comprehensive analysis, more data from various sensors needs to be collected. For example, DigiMine connecting to the national seismic monitoring system or to the local mine’s seismic monitoring system. Such connections will enable the development of a better self-analysis system and possibly prediction of future events. More importantly, it will contribute to better understanding of regional seismicity and its potential impact on excavation design. CITATION:Kwiri, J, Zvarivadza, T, Cawood, F and Mitra, R, 2018. How efficient is DigiMine technology in recording earth movements? A look at the Botswanan earthquake, in Proceedings The Fourth Australasian Ground Control in Mining Conference (AusRock), pp 414–419 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 30, 2018

DuPont is a chemical and energy multi-national of approximately 90,000 employees. Often regarded as the world leader in injury reduction and process safety management, DuPont operate 140 manufacturing sites around the globe. Conoco is a wholly owed subsidiary of DuPont which is involved in oil, gas and coal exploration.   Throughout this paper I will discuss DuPont statistics, developing a safety culture and training process as well as discussing possible short comings in the New Zealand safety focus. I will conclude with my recommended improvements and issues for New Zealand companies to focus on.   It is very difficult to compare DuPont and New Zealand statistics through lack of compatibility in recording methods and my ability to interpret ACC's Injury Statistics. However through considering DuPont's statistics, and comparing them to your own companies or departments, you will agree they are indeed impressive. I hope that by discussing DuPont's safety philosophy, and possible shortfalls within New Zealand Legislation many of you will find ideas and inspiration which will help you to further reduce your own injury rates.

Jan 1, 1997

In current mining practices it is desirable to bring about a substantial increase in both rate of face advance and productivity, thus compelling the mine engineer to consider better and more productive ways of mining. Transportation plays a vital role in achieving improved productivity. This paper focuses on horizontal transportation systems. Horizontal transportation is defined from the shaft station area to the end of the stope cross-cut. Traditionally, horizontal transportation is inefficient in comparison to vertical transportation efficiencies and accounts for a high proportion of South African mine accidents. Thus, the role of horizontal transportation has been investigated in detail, as it offers the greatest chance for improvement. The purpose of the paper is to provide a best practice guideline for the design of horizontal underground transport systems. It is intended that the document be used by mine designers and planners as an aide memoir during the design process and benefit may well be gained from retrofit and reorganisation activity. The paper looks at transport systems suitable for deep level gold mining in South Africa and evaluates such items as management, scheduling, and haulage systems. Current transportation systems for personnel, material and rock transportation are evaluated, gaps in technology highlighted, and recommendations made.

Jan 1, 2003

BHP Billiton Mitsubishi Alliance, or BMA, is AustraliaÆs largest coal miner and exporter, and is currently responsible for around a quarter of AustraliaÆs total annual coal exports. BMA and its predecessors have been part of the Queensland mining scene for around 40 years, developing world-class mines, a port, overseas markets, and an international reputation for quality and reliability. From its production base in QueenslandÆs Bowen Basin, BMA produces a broad suite of coals which are supplied to 73 customers in 24 countries. BMA was formed in June 2001 as a partnership between BHP Billiton and Mitsubishi Development Pty Ltd, under which the two companies share equal ownership and management of eight Central Queensland coal mines û Goonyella Riverside, Broadmeadow, Peak Downs, Saraji, Norwich Park, Gregory, Crinum and Blackwater û and the Hay Point coal export terminal near Mackay. This case study focuses on Peak Downs Mine, which was the second largest open cut mining operation to be developed in the northern Bowen Basin for the original CQCA Joint Venture. The first coal was mined in April 1972 and today, Peak Downs has a production capacity of over nine million tonnes of coking coal per annum. The mine is located 30 km south of Moranbah and 195 km south west of the Hay Point port facilities. Coal is mined by open cut mining methods using six draglines and two truck/shovel stripping fleets for overburden removal. Coal seams are mined using excavators and front-end loaders and 210 tonne capacity coal haulers.

Jan 1, 2007

The reality is that in today's world almost half of nearly six billion people on the planet do not have access to commercial energy and the services it brings. Based on UN projections, in 30 years time there are likely to be nearly three billion more people in the world, over 90 per cent of them in countries which are already economically poor. The World Energy Council (WEC), through its 102 member countries, monitors trends and developments and projects future trends. WEC is a non-governmental international body representing all forms of energy and is committed to the sustainable use of energy for all mankind. This paper is based on WEC studies and papers presented at its many conferences and congresses worldwide. Primary energy demand growth is dominated by the developing countries over the next 30 years. The world energy mix is projected to change very little over the next 30 years. Fossil fuel supplies (ie coal, oil and gas) are likely to decline from 77 per cent to 73 per cent, nuclear energy may grow from five per cent to six per cent and renewable energy sources (eg hydro, solar, geothermal, wind, tidal and biomass) could increase from 18 per cent to 21 per cent. World energy consumption is expected to grow by over 50 per cent over the next 30 years. The paper reviews changes in energy demand in the world, particularly in the Asia/Pacific region. Environmental issues are covered, as are developments such as solar energy from space and the status of renewable energy forms. Agendas for action to achieve change are also reviewed.

Jan 1, 1997

By Watt KL

Chemical anchors for use in rock bolting have been produced in Australia under licence for several years. These anchors are alternatives to the more normally used mechanical anchors and give improved anchorage strengths under some conditions, although at greater cost. Considerable development during this time has resulted in an improved sausage-type chemical anchor more competitive in price, to such an extent that its use is increasing markedly. Particular-improvements allow load application up to the strength of the bolt within 2 min, reduction in cost, self-extinguishing features in the resin, improvements in manufacturing techniques, and an improved water- insensitive casing. At the same time, smaller bolt sizes have allowed reduction in resin volumes with consequent cost reduction. At this stage several aspects remain to be improved, particularly specialty anchors for specific purposes and Packaging.

Jan 1, 1971

A continuing demand for exploration geologists, at a level well below that during the mineral "boom" of 1967-1971, will be highly selective. The exploration geologist must be more than the traditional geologist whose primary function has been detailed description of rocks and their recording on a geological map. He must be capable of 1. reconnaissance recognition of favour= able environments for ore mineral concentrations, 2. application and interpretation of techniques of search and evaluation, and 3. evaluation of economic, technological and political interactions that combine to make an ore deposit. Universities have an obligation to their students to provide them with a saleable skill, to educate them so that they can cope profess- ionally and socially, and to provide a mechan- ism by which education can be a continuing process. Humanistic and social studies, develop ment of communication skills, understanding of economic and management principles, ability to assess rock properties that influence extract- ion and beneficiation, and a knowledge of technological developments and limitations are necessary parts of the exploration geologist's

Jan 1, 1974

By Runge IC

The mine planning process is reviewed and appropriate software considered in terms of "line process" or "support function". The mine planner's requirements of a geological model and the elements of and requirements of a computerised mine planning system are all discussed. The use of "support" software for mine planning is considered and general rules for its development are given. Important changes involved in implementing a computerised mine planning program are listed.

Jan 1, 1983

By AUIMM AUIMM

Continuous Improvement The Council of the AusIMM should expedite the introduction of a continuous professional education policy along the lines of that to be proposed to you by David Pollard today. The Education and Accreditation Committee must continually review the training needs of the next generations of mining industry professionals. It should continue to demand and encourage the creation of the schools for the training of such people. The AusIMM could even put greater onus upon university researchers to accredit university post graduate degrees.

Jan 1, 1994

By C Riley, N Davies, J Carpenter, I Lipton

Nautilus Minerals Incorporated (Nautilus) recently announced the worldÆs first Seafloor Massive Sulfide Mineral Resource at Solwara 1 in the Bismarck Sea, Papua New Guinea . The discovery, exploration and resource modelling of this æblack smokerÆ system located 1500 m under the sea involved unique technological development. Whilst the resource estimation methodology had similarities with approaches adopted for analogous volcanic-hosted massive sulfide (VHMS) deposits, specific parts of the resource estimate called for new ways of assessing data. This paper discusses several innovative methods for collecting and assessing Solwara 1 exploration data. This ia an ABSTRACT only. A full-length paper was not prepared for this presentation.

Jan 1, 2008

By Brouwer G, Shaw J

As South African gold mines go deeper, and improved and more uniform working condi- tions are required, ever larger amounts of refrigeration are needed. At the same time new and more suitable cooling equipment is becoming available for use with new mining layouts as well as on existing shaft systems. The advent of the large diameter rotor screw compressor has meant that there is now a machine available with great flexibility in performance and construction for efficient underground use. The first installation using this type of machine is described.

Jan 1, 1988

Iron and steelmaking slags have been utilised for a century. All dumps are now exhausted. Because of constraints in establishing new stock yards, all slags have to be utilised immediately. At present, this is being achieved. Only in a situation where there is an increase in pig iron and crude steel production, together with the impact of new residual materials competing from other industries can marketing problems be anticipated.

Jan 1, 1979

By C Nucifora, M Landers, J Jones, G Maddocks, K Mandaran, A Forbes, W Wilson, S Newman

Glencore’s Mount Isa Mines Limited (MIM) operates the Mount Isa open cut and underground copper (Cu) and zinc-lead (Zn/Pb) mines near Mount Isa in Queensland, Australia. Tailings from processed Cu and Zn-Pb ore is contained in a 1,315 ha shallow (< 35 m deep) multi-cell valley fill tailings storage facility (TSF). Static geochemical testing conducted by MIM over the life of mine (LoM) verifies that the Cu, and Zn-Pb tailings has a wide range in sulfide content and diverse mineralogy with significant acid neutralising capacity (ANC) in some samples. The tailings are predominantly classified as potentially acid forming (PAF) using static analytical methods. Kinetic leach testing using free draining columns and humidity cell tests simulating tailings placed on the surface of the TSF suggest that the tailings samples are likely to remain non-acid forming (NAF) for 10 to 40 years under aerial exposure, and much longer than this under saturated conditions within the TSF. During this period of weathering, as ANC is depleted, the neutral pH drainage may contain elevated concentrations of some elements including sulfate, manganese and zinc. Only when the ANC is depleted would the tailings then begin to produce acid drainage. CITATION:Mandaran, K, Jones, J, Nucifora, C, Maddocks, G, Landers, M, Forbes, A, Wilson, W and Newman, S, 2018. Mount Isa Mines Rehabilitation Materials Sampling and Analysis program for closure planning, in Proceedings Life-of-Mine 2018, pp 138–140 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 25, 2018

By Schmidt LC

The method of supporting excavated roofs in underground coal mines by conventional roof bolting systems is challenged due to its shortcomings of being time-consuming and leading to possible unsafe installation. Though a few alternatives have been considered, the ultimate and most efficient bolting method has often been conceived as one using a self-drilling roof bolt, or a Rapid Face Bolting System (RFBS). The on-going Rapid Face Bolting Project undertaken by the University of Wollongong includes a special tubular bolt design.The tubular bolt designed for the RFBS is a "single-pass" bolt equipped with cutting tips used to drill a bolthole to accommodate the bolt. Different from that of the coring bit employed in geological site investigations, the principal design consideration for the tubular bolt is low cost associated with a small working life for the cutting tip.

Jan 1, 1991

Exploration requires substantial capital, and is an extremely risky business (only 1 in 100 prospects ever becomes a mine). The average lead time, that is the time between discovery and production, varies from around two years for a gold mine, to 15 years for a lead/zinc mine. Since it takes years to find, prove and develop most ore bodies, exploration must be carried out years ahead of the depletion of existing deposits. Investors in exploration are exposed to risk for long periods before knowing whether they will receive a return on the funds invested. The risk, high-cost, uncertainty and long lead times involved in exploration make it an aspect of commerce that most managers and investors find difficult to rationalise or understand. Nevertheless, it is a given that the long-term survival of the mining sector depends on discovery of new mineral deposits, however the immediacy of the need to find or acquire new mineral deposits in order to compete and prosper in the industry is less well understood. This paper examines the commercial realities which underlie exploration for new mineral deposits. The first and foremost reason for exploration is to maintain or increase depleting ore reserves which are the asset base of mining, but there are other compelling commercial reasons for exploring, and these are: to maintain return on investment, to achieve growth or create wealth through discoveries which lead tonew mining ventures, to remain competitive in the industry, to diversify, and to control raw material source for mineral processing and/ormarketing ventures. Exploration is necessary for survival of the industry, and also for survival of organisations competing in the industry. The organisations which discover the best orebodies are in the best position to compete, and mining organisations which fail to find or acquire new mineral deposits rapidly become uncompetitive and unable to maintain return on shareholdersÆ investment.

Jan 1, 1998

By Mirabediny H, Whitchurch K

A computerised simulation model has been developed to select the most suitable digging method of a dragline operation for a given geological condition. The developed procedure uses a geological ore body model as the basis for the geologic database. The simulation selects the most cost effective dragline digging method from a database of various dragline digging methods The database consists of common and innovative dragline methods currently used in Australian open cut mines. A generalised computer package, DSLX, was extensively used to simulate various dragline digging methods. The DSLX software uses predefined functions to build strip geometry, working benches, blast profiles and spoil piles. The outputs from DSLX in form of volumetric, swing angles and hoist distances data are then aggregated with dragline specifications and site time study data to compare productivity of selected digging methods. The result of a case study showed that this procedure lends itself to the 'optimum' selection a dragline digging method for a given coal deposit.

Jan 1, 1995