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Basic premises for evaluating special characteristics of gold-bearing porphyry metal systems stem from their contrasts with properties of the class as a whole. Included features are differences in geologic, thus tectonic, environments, subtle but real differences in the proportions of accessory metals Mo-Ag-Au that are regionally and within some regions, tempo-rally distinct, contrasts in the Ag:Au ratios, petrological-geo-chemical as well as isotopic differences between intrusive suites, the age and nature of host terranes, contrasts in alter-ation style, and zoning variations of mineralogical and physical properties of rocks. These properties are linked in various ways in different regions and suggest that in large gold-bearing systems where gold may be uniformly distributed, environ-ments of emplacement, and compositions or sources of igneous "progenitors" may dominate in importance over processes, and that systems in which gold is zoned are processes-dominant.

Jan 1, 1990

By Collins L

The commercial success of a mining project can be strongly influenced by the business activity which takes place away from the mine site. The project revenue is determined by marketing success which results from persistent research and full realisation of suitable products and by-products and appropriate upgrading achieved in conjunction with proper material security and insurance. Significant costs of transport can be optimised, protection of the environment carefully managed and skilled employees acquired as a valuable asset. Working capital requirements are often substantial and should be carefully established and financed, possibly by special contractual arrangements for product sales.

Jan 1, 1997

By Burgess J

Present practice of lead-zinc flotation at North Broken Hill Limited is described and factors influencing plant objectives and performance discussed. Mineralogical examination of final flot- ation products showed mineral liberation to be 94T complete and size by size metal recovery tables indicated a need for finer grinding to improve lead and silver recovery, but coarser grinding to improve zinc recovery. A steady grinding circuit, at constant ball mill power and cyclone overflow pulp density, is found desirable for satisfactory flotation circuit operation because instabil- ity in the grinding circuit inevitably leads to flotation instability and as a consequence less than optimal flotation operation. Remov- al of the variable lead flotation middling product from the grinding circuit decreased grinding instability.

Jan 1, 1978

By C Robertson, J Campos

The South African mining industry first experienced en-masse use of electronic detonators in the Narrow Reef environment using AELÆs ElectrodetÖ pre-set delay system. In recent years, programmable systems such as AELÆs SmartdetÖ have also established their position, and within both AEL and the mines there has been important learning around the strengths and weaknesses of these systems. In general, the fixed delay systems tend to be more easily appreciated by less-skilled work teams, and are very well suited to simple layouts, especially long, narrow blasts. However, development of programmable row controllers and series delay inserts has greatly expanded the field of usefulness of these systems while retaining most of the simplicity of use. The programmable systems are immensely flexible and therefore able to function under any condition, but require a higher level of discipline and knowledge. Much has been done to address this issue and make the systems user friendly, so the systems have converged to some extent. These systems are both valuable tools for achieving control over blasting in underground and surface applications. The choice of system is very dependent on the prevailing conditions. Accurate timing with electronic enhancements continues to show an increasing range of benefits to mining operations. There is a strong parallel with non electronic initiation systems which helps to understand the appropriate use of the systems.

Jan 1, 2001

Outbursts of coal and gas are coupled both in their nature and mechanism and take place under varied sets of physical and geological conditions. The main interacting factors are geology and seam structure, seam gas composition and pressure and strata stress. By pre-draining the seam gas in advance of workings one of the factors contributing to outbursts is removed. One method of pre- draining gas from the coal seam or from areas of geological disturbance is to drill long horizontal holes in the coal seam. The technology to drill horizontal holes up to 600 m in the coal seam is now available by hydraulic control of the rotation and thrust on the drill bit and accurate survey methods to determine the vertical and horizontal position of the drill bit.

Jan 1, 1980

By Barnes E. L S

With the introduction of diesel powered loading and hauling equipment, a number of Australian mines producing less than one million tonnes per year from shallow orebodies have been dev- eloped by decline. This method of entry has the advantage of providing both flexible access and early prod uction. However, as the depth of mining increases so does the operating cost of haulage, due to the need for more trucks. This cost, together with increased capital requirements for both equipment and infrastructure, leads to the point where the alternat- ive of shaft hoisting must be con- sidered. With an established decline it is possible to provide an ore hoisting shaft using a drilled raise with subsequent stripping to a suitable size. Using DCF techniques and known equipment operating and capital costs, an economic comparison of the two systems is made to determine the limit- ing depth to which truck haulage can be used.

Jan 1, 1973

By E Hogan, M Goodz, R Wright

The planning, permitting and monitoring procedures of the re-opening and rehabilitation of mine sites is an ongoing process which must continue throughout and beyond the life of the project. Both industry and government bodies must remain flexible to allow guidelines to be altered where and when necessary.To enable the successful re-opening of the Morning Star mine at Woods Point in alpine Victoria, many environmental and historical issues had to be evaluated.The site which had been derelict for 28 years had to be rehabilitated to a safe and aesthetically pleasing state prior to construction of a new operating mine site. Considerable liaison with government authorities and the local community was required.

Jan 1, 1992

Seven papers included in Session 8 of the Third International Mine Water Congress under the heading "Achievements in Mine Water Management & Research" have been reviewed. Only one paper, a case study by Masters on biological treatment of inorganically polluted effluent, has any connection with research in the sense of seeking new, generally applicable knowledge which would advance the frontiers of mine water management. The remainder deal with various aspects of the management of mine water ranging from investigation of the geology of a specific aquifer system through operating dewatering systems to the management of specific effluent disposal problems.

Jan 1, 1988

By Gao H

Based on the author's research and plant practice experience of the last decade, several technological approaches have been developed to increase the recovery of gold and silver associated with sulphides. This paper gives a general discussion of some technological problems encountered in this area in five aspects and introduces the different approaches employed in three typical mineral processing plants to increase recovery of associated gold and silver. On the basis of studying occurrence characteristics of gold and silver minerals in sulphide ores and of determining loss locations of gold and silver on flotation process, a remarkable improvement on the recovery of gold and silver in all these three plants was made by choosing proper grinding fineness, using combined collectors of good selectivity, properly decreasing the grade of main metal concentrates, making reasonable arrangement of the products of main metals, or a combination thereof.

Jan 1, 1993

Due to geographical location, AustraliaÆs economy and trading are closely related to Asia. With ChinaÆs increasing demand on resources and energy and Japan and KoreaÆs steady imports in these fields, AustraliaÆs mining industry is experiencing a so called æboomÆ period. Traditionally, engineers or skilled workers from South Africa, Britian or other parts of Europe moved to Australia for its mining industry. Now, more students from Asia are starting to choose mining engineering (similar choices include mining geology, metallurgy, geotechnical engineering and mining surveying) and expect to work in these fields. How does AustraliaÆs mining industry face such a situation? What kinds of challenges and opportunities do the mining industry and universities face? How do mining companies utilise these human resources? This paper concludes with an analysis of all these questions at an industrial level and some personal deduction as to the preferred course for international students.

Jan 1, 2005

Extensive personal experience in the USA and Australia has shown that Australians working in suitable work environments are capable of world-class performance. To build such work environments, mining leaders need to ditch two common management approaches that have not succeeded. Firstly, stop relying on traditional methods of trying to change people's behaviour simply by using communication alone to change attitudes and then change behaviour. Analysis of human behaviour explains why this approach fails in all industries. Secondly, stop trying to improve productivity by just running harder and increasing capital investment. Understanding work processes explains why this approach has limited success.

Jan 1, 1995

Almost all industrial products, such as buildings, cars, plastics, railways, radio and television sets, computers, and others are made from materials extracted from the Earth. Earth is main resource of energy and up to now; the energy has been derived mainly from natural resources. Mining industry has significant influence to the nature, sometimes evokes a devastation of nature. On the other hand we have got a lot of nice examples that good preparation, sensitive mining practice and consistent reclamation can minimise the negative effects. All the mentioned problems calls for effective tools for mine design, mine operation and mine reclamation. Third millennium brings next challenge given by advances in information and communication technology. The development of very sophisticated software tools provides to technical systems some features of autonomous æthinkingÆ and intelligent behaviour. We can find large effort and a lot of scientific papers reflecting last advancement in science and technology and providing inspiration for new mining technology of third millennium called Intelligent Mine. Some aspects related to creation and utilisation of æIntelligent ModelsÆ as a background of æIntelligent MineÆ are presented and discussed in this paper.

Jan 1, 2003

Access to secure and reliable water resources is fundamental to the minerals industry. In recognition of that requirement, and cognisant of extensive contemporary public water debate and reform initiatives in Australia, the Minerals Council of Australia (MCA) approached the Ministerial Council on Mineral and Petroleum Resources (MCMPR) proposing the establishment of a Joint Working Group to prepare a framework of strategic principles to ensure responsible water management at a site and corporate level, manage risks and identify opportunities. The Framework provides high-level guidance on issues that should be addressed in water decision making across Australia in relation to mining and associated processing operations. It identifies principles and objectives for adoption in four areas, viz: valuing water, strategic water planning, implementation, and engaging stakeholders. Given the high level nature of the Framework, and its national application, it does not seek to replicate detailed guidelines already widely available in each state and territory on operational water management practices and associated regulatory issues at mine sites. The Framework includes a series of case studies from across Australia that demonstrate where strategic thinking, wise water management and close consultation with stakeholders has delivered better water use, more profitable operations and excellent community/stakeholder relationships. The Framework was formally launched on behalf of MCMPR by the Western Australian Minister for Resources at the MCAÆs Sustainable Development Conference in Perth in October 2006. No full paper available for this extended abstract

Jan 1, 2006

COAL constitutes such a gigantic item in modern industry, either for direct heating, production of coke for smelting, or for the generation of power, that its quality and price play a very significant part in economic industrial progress. Australia is still a very young country industrially, and is groaning under many disabilities compared with competitors overseas, not the least of which is the quality of coal. Linked with the word "quality" should be that of "utility," for high-ash content prevents efficient utilization of the fuel.The marketing of good quality coal is a very important matter indeed, and if industry in Australia is to progress in the way that it should, this matter must receive keen attention.New South Wales, above all the other Australian States, has been blessed by nature with vast coal-fields, from which fuel is shipped to every State, and provides the base for power for most of our railroads and industries.Experts frequently refer to the fact that in some districts only partial extraction of thick seam coal is being made, without a care or thought for the future. Ranking next in importance to this is the fact that much of the coal is being carelessly marketed.Very few collieries in Australia are equipped with coal-washing plants for dealing more particularly with small coal grading which most industries require, and to which coal producers as a whole pay the least attention. In England each year nearly20,000,000 tons of coal is being water-washed before sale, and is marketed as a fuel of far greater utility once it has been freed from extraneous ash.Investigation proves that a great many pits in New South Wales are marketing coal (more particularly small coal) containing a considerable quantity of extraneous ash, due to the admixture...

Jan 1, 1926

By Simes C. D

Results of experiments for dissolution of zinc by aeration of sphalerite in glass, copper, galvanised iron and stainless steel vessels of identical dimensions are reported. It was found that in a glass container dissolution of zinc reaches a maximum after 30 min aeration and then decreases whereas in the copper container dissolution remains nearly unchanged up to 30 min aeration and then increases. In the cases of galvanised iron and stainless steel containers zinc dissolution increased steadily with time up to 60 min aeration. It is suggested that the different rates of dissolution in glass and copper containers may be due to electro-chemical actions.

Jan 1, 1984

By Fengyan D

Removing the interference of latter events, the data of geophysical (such as gravity and aeromagnetic) anomalies may indicate whether the mobile belt exist and whether the adjacent terrains of the mobile belt originally belong to one single unit. The petrotectonic assemblage can provide informations about the tectonic setting where it was generated from. The structural style can exhibit the kinetic and kinematic processes. The form of ancient isogeotherm may reflect the ancient geothermal regime which is related to the tectonic mechanism. In general, the early Precambrian terrains suffered polymetamorphism and multiple structural deformation. The researches must be carried out for the distribution of paleogeotharm and m.tamo'phic facies and zones on the basis of recovering the early structural style with structural analysis method; then a relatively correct conclusion may be geined on the ancient geothermal regime. This method can be known as "Ancient Thermotectonic Analysis". Through the sythetical research, a real knowlege about the tectonic setting of early Precambrian mobile belt can be obtained.

Jan 1, 1990

This paper outlines the role of commissioning in the project cycle, shows how to get organised for commissioning and describes the principal commissioning activities. Emphasis is placed on appointing key commissioning staff early in the project to coordinate the preparations for commissioning and on detailed planning and tracking to ensure that the required commissioning activities are performed satisfactorily. The management of safety during commissioning is reviewed.

Jan 1, 2005

By Collins AR, Meares RMD, Graham JM

Exploration programs for both alluvial (placer) and hardrock platinum group metal deposits are being conducted in Papua New Guinea by a joint venture between Degussa AG and Pancontinental Mining Limited. Prospective areas were defined on the basis of ultramafic/ophiolitic source rocks shedding detrital platinoid grains. Field sampling techniques including churn drilling, together with appropriate laboratory analytical and mineralogical techniques, were developed and are contributing to the success of the exploration programs.

Jan 1, 1987

The majority of coke in Australia is made in by-product slot ovens at steelworks in Port Kembla, Newcastle and Whyalla. Most of the coals for these plants come from New South Wales but a regular proportion of Queensland coals may be introduced. The plants and the coals are reviewed in the paper.

Jan 1, 1975

It is a facet of modern-day life that change, even of a revolu- tionary nature, normally passes without comment. People have become so conditioned to continuous improve- ments in every aspect of their lives that they would be surprised only if there were to be no change. This paper seeks to demonstrate the extent of technical change, and to indicate the need for a fuller advantage to be taken of the technologies available, or potentially available, to the profes- sion. It contends that the mineral industry has been particularly slow to embrace technical change, and has good reason to con- sider an improved attitude for both prosperity and survival.

Jan 1, 1988