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This paper reviews the geochemistry of weathered nickeliferous sulphidic and lateritic profiles, the supergene behaviour of nickel and ore-associated elements, and their implications for exploration in an attempt to distinguish between barren and mineralised nickeliferous profiles. Nickel is an abundant accessory element in ultramafic rocks with background concentrations in some units up to 0.25 weight per cent. Ore-grades in fresh rock are mostly associated with massive and disseminated sulphide zones within magnesium-rich layered ultramafic sequences. In lateritic weathered terrain, nickel is also concentrated in the regolith profile. This process not only upgrades nickel in the gossanous weathered product of sulphidic deposits, but for sub-economic sulphide zones and some ultramafic rocks, is sufficient to result in a supergene resource. Ore-grade accumulations of nickel in regolith after sulphide-poor ultramafic rocks are referred to as lateritic deposits. Nickel sulphide zones and their ferruginous weathering products are collectively referred to as sulphidic deposits and are the major source of nickel in Western Australia. Mineral exploration in the Yilgam Block is hampered by deep lateritic weathered profiles (eg Butt and Sheppy, 1975; Smith, 1977; 1982). During the nickel boom of 1967 - 1972, most discoveries resulted from the location of outcropping nickeliferous gossan and ironstone. Exposed ultramafic terrain with nickel sulphide potential were explored intensively, mostly by gossan and soil sampling. However, up to 85 per cent of the area of the Yilgarn Block is buried by transported regolith. In these covered areas, barren and mineralised rock responses at the surface are similar and soil sampling produced unreliable results due to many false anomalies. A statistical, multi-element approach to regional geochemical exploration has evolved. Potential trace element indicators investigated, include Co, Cr, Cu, Ir, Mn, Pb, Pd, Pt, Sc, Se, and Zn. In recent years, trace element ratios have also been tested with varying degrees of Success.

Jan 1, 1996

Newmont Waihi Gold operates the Martha Mine open pit at Waihi, New Zealand and is developing the Favona Underground Project two kilometres to the east. The Company is exploring the Waihi district under eight exploration permits totalling 6300 hectares.   Martha Mine is scheduled to close in late-2006. The Company has instigated and funded a significant programme of community consultation to mitigate the effects of mine closure on the community and enhance effective participation in the selection and provision of appropriate community facilities post mining.   This paper provides an overview of current issues and future developments.

Jan 1, 2004

A vigorous seismic and drilling programme has been conducted over.ar area of .59000 square miles in the Roma district during the last three years. The work is Mill' in progress and although many new geological concepts have been discovered, he subsurface geology is not yet finalised. D.atailed examination has shown many variations of .section, has established the general basement trends and sedimentary thicknesses, has shown that much more of the section is marine than previously thought ~nd has indicated that any reservoirs throughout the section could be potential oil ind/or gas producers if suitable traps are located.

Jan 1, 1962

Australia has historically been a world leader in mining innovations. This trend is reflected in the international patent records, which show that in recent years there has been some recovery in the number of patent filings arising from Australian research. These innovations occur across a wide cross-section of mining technologies and derive from both public and private sector research. Australian mining innovations are largely dominated by new processes and equipment, principally in the areas of rock drilling and coring, strata stabilisation, cutting tools, blasting, mine design and oil field exploitation. They include improvements in drill bits, rock bolts and accessories and wellbore systems. Another area that has received significant research attention has been the in situ thermal processing of coal deposits. High profile examples of Australian mining innovations include the æSORDMinerÆ, a remote-controlled mining machine for use in mining collapsing wet environments, and CSIROÆs SMART*CUT rock cutting pick that dramatically increases the rate of cutting hard rock. This paper will provide an overview of recent innovations in Australian mining, as reflected in the international patent records, including the organisations and individuals active in the field, and the technological nature of specific innovations.

Jan 1, 2008

By Ngai WCT

Over 90 per cent of the explosives in Hong Kong are used in civil engineering works. The Hong Kong Government controls all explosives and delivers on a daily basis to each site which it has licensed. Such deliveries need to be arranged the day before actual delivery. With the vagaries of the traffic in Hong Kong, contractors do not necessarily know the time of arrival of explosives. Contractors in general would like to reduce their exposure to these potential delays and the high cost of explosives deliveries. The high population density and urbanisation means that rock blasting has to be carried out in close proximity to other property. In order to protect life, property and utilities, it is not only necessary to employ proper blasting techniques but also to adopt effective safety measures. The Route 3 Advance Earthworks project is located on the north-west corner of Tsing Yi Island, Hong Kong. It is one of the Airport Core Programme projects for the new Chek Lap Kok Airport. Secured by Leighton Contractors (Asia) Ltd in early-1992, the work commenced in May of the same year, with completion and handover to the Hong Kong Government in May 1995.

Jan 1, 1995

By K H. Esbensen

The Theory of Sampling (TOS) has contributed significantly to chemometrics by allowing data analysts to become more aware of total measurement uncertainty as total sampling error + total analytical error. This has allowed a new view on, for example, validation of multivariate data models and their performance. This keynote focuses mostly on the reverse perspective: how can chemometric multivariate data modelling be of help in an augmented sampling context? The basic principles of multivariate data analysis are presented and application examples are outlined from several areas in the geosciences to facilitate answers to the question posed, including a geochemical multivariate anomaly concept defined by a multivariate background model. Applications from geochemical prospecting, geochemical mapping, environmental chemistry and anthropogenic outlier recognition are outlined, as are the interdependent relationships between geostatistical modelling (variographics) of singular variables versus linear combinations of a multitude of variables, in chemometrics called scores. The potential synergy between chemometrics and TOS is far from exhausted at this time; much work remains.CITATION:Esbensen, K H, 2014. Theory of sampling in a multivariate perspective – what can chemometrics contribute?, in Proceedings Sampling 2014 , pp 7–10 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 29, 2014

By R Valenta, A Littleboy

Geological heterogeneity is one dimension of complexity in mining. Significant effort is put into developing an understanding of this complexity so it can be used in resource estimation, mine planning and economic modelling. However, over the decadal lifespan of a mining venture, many other dimensions add to the complexity of a mining operation. These include: technological evolution, market fluctuations; investor confidence; social norms; local expectations; and ecosystem functionality. As with geology, these factors are all heterogeneous, uncertain, time varying and represented through sparse and incomplete datasets. Recent work (Valenta et al) is beginning to show us how these risks correlate in different global settings. By analysing data relating to known, but as yet undeveloped copper deposits, this work (the complex ore body database) is demonstrating that it is the combination of issues (both price sensitive and non price-sensitive) that determine the viability of a deposit for extraction in the 21st century.CITATION: Littleboy, A, Plint, N and Valenta, R, 2018. Mining as a complex system: do we need a new model?, in Proceedings Complex Orebodies Conference 2018, pp 41–43 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 21, 2018

At the beginning of this year it was my pleasure and responsibility to take over the Presidency of our Institute from Mr A. A. Parish who, as did his predecessors, filled the office with distinction. It is a great privilege to address you as President and it is an occasion for my wife and family, and I am most grateful for your inviting them to the buffet dinner. Our Secretary (Miss Jacka), who processes all Presidents, has told me that there are neither questions nor discussions on Presidential Addresses, and that being so, I felt free to select a controversial topic. The address I have prepared is not strictly true to label; because I intend to include also the effect on agricultural production in Australia if Britain joins the European Economic Community (i.e. the Common Market).Three points of view are1. the European, which is one of equanimity deriving from the initial brilliant success of their scheme,2. the British, which is one of anxiety not to miss the bus, coupled with a commendable wish not to inimically affect existing Commonwealth arrangements,and3. the Australian, which is one of alarm.In England all are drawing their own conclusions on the subject and views range from the extreme desirability, to the extreme undesirability, of the United Kingdom joining.No one in Britain wants Australia, or New Zealand, to...

Jan 1, 1962

On the 18th November, 19'58, the first coal was delivered to the Morwell Power Station from the adjacent Open Cut using conveyors for the transport of the coal from the working face to the boiler bunkers. As the cut develops the coal seam will be worked for its full depth of about 360 feet from four benches, each feeding a conveyor line along th.e face and up out of the cut to the power station and briquette factory. By 1970 the estimated maximum daily demand reaches 60,000 tons and the total annual output 18 million tons. The complete conveyor installation will then total some 9 miles with a capital cost of over £3~ million.The choice of conveyors in place of the more usual rail system was made possible by the development of movable belt conveyors which use mechanical conveyor shifting, high belt speeds and flexible high strength belts and the paper deals with these and some other aspects of the scheme.INTRODUCTIONThe development of brown coal deposits is usually based on open cut workings equipped with a few large dredgers giving an almost continuous output of coal or overburden which has to be hauled a comparatively short distance. These are ideal conditions for conveyor operation, and it is surprising that, until recently, rail transport has been used almost exclusively in brown coal open cuts. In some cases inclined conveyors have been introduced to take the coal from the coal levels up out of the cut to bunkers at groundlevel, but trains have been left to operate between the ditch bunker feeding the conveyor system and the dredger.

Jan 1, 1960

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

pNumerical modelling has been used to examine the relationship between the results of two commonly used methods of assessing the propensity of coal to spontaneous combustion, the R70 and Relative Ignition Temperature tests, and the likely behaviour in situ. The criticality of various parameters has been examined and a method of utilising critical self-heating parameters has been developed. This study shows that on their own, the laboratory test results do not provide a reliable guide to in situ behaviour but can be used in combination to considerably increase the ability to predict spontaneous combustion behaviour./p

Jan 1, 2005

By T G. Measham, D A. Fleming

When attempting to understand potential regional or community socio-economic changes that resource-extraction industries may produce, it is important to analyse the channels that promote these changes. In this study, we propose a conceptual framework to better understand how socio-economic effects are likely to emerge in regions impacted by mining. The framework considers three levels of hierarchical effects (Measham, Fleming and Schandl, 2016).In the first level, the resource-extraction industry causes four direct initial impacts on nearby communities: labour demand shock (mining employment generation), income generation (compensation to landowners and higher wages), environmental consequences and land tenure/Aboriginal issues and an increase in local tax revenues.The second level is shaped by the subsequent population increase (given by immigration of permanent or temporary residents) produced by the new levels of employment and income that resource windfalls can generate in resource-extraction regions. These increases in employment, income and population become the source for a rise in the demand for local (and non-local) goods and services.Finally, the third level is given by boomtown-like and other socio-economic effects generated from the initial effects.CITATION:Measham, T G and Fleming, D A, 2016. A conceptual framework to understand the local community/social impacts of mining, in Proceedings Life-of-Mine 2016 Conference , pp 188–190 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jun 28, 2016

The classical view of island arc geology is that of a plutonic intrusive/volcanic extrusive complex, derived from the products of oceanic lithosphere subdu.ction and constructed on an over-riding plate of oceanic origin. Such an arc is typically backed by a marginal basin, formed by seafloor spreading of a more or less conventional kind. Various studies undertaken over the last decade have modified this picture and provided a new tectonic framework within which to explore for resources. Formation of Marginal Basins During the 1970s, seafloor spreading magnetic anomalies were identified in various marginal basins in the SW Pacific. In one of these, the South Fiji Basin, there was clear evidence of a ridge-ridge-ridge triple junction, although no kinematic relationship to the major plate boundaries was determined. Palaeomagnetic studies conducted in Vanuatu and Fiji, and in the Bismarck Archipelago of PNG provided evidence of large scale arc rotations relative to major plates. This indicated a general pattern of marginal basin formation by ridge-ridge-ridge triple junction growth together with island arc growth by trench-ridge-trench triple junction evolution. Formation of Primitive Island Arcs The triple junction growth model strongly suggests that at least a significant amount of arc evolution occurs by the initiation of subduction at a spreading ridge. This has predictive implications for the nature of island arc basement.

Jan 1, 1987

By G De Tomi, R Sousa, A Lapworth

One of the current challenges for iron ore producers is the ability to respond to changes in ROM stockpile specifications in a quick and cost-efficient manner. The decision-making process to respond to such changes is normally associated with grade-control and short-term mine planning activities, from where new operating instructions to the mine are provided. Mines are under increasing pressure from changes in the industry, such as a scarcity of skilled staff; a higher turnover of skilled employees and tighter product specifications. The quality of operational activities easily suffers as a result of these pressures. The technology that supports operational activities is often poorly implemented, which results in systems being unsustainable and poorly understood by the organisation. All successful technology implementations rely on the people, processes and technologies involved being well understood. Because of the complex nature of mining, the processes that underpin mine planning, scheduling and operational control are often not well defined. This results in activities undertaken by individual departments being poorly integrated. Datamine has developed a set of tools and methods for decomposing; capturing and documenting processes and ensuring those are embodied in implemented solutions. A case study of such a solution is the GEROS planning system, which has been successfully implemented at CVRDÆs Southern Iron Ore System, in Minas Gerais, Brazil.

Jan 1, 2005

By Clark T. M

Underground coal mining involves the disturbance of natural strata stresses formerly in equilibrium, the production of noxious and flammable gases and dust which can be both an explosion and a health hazard. It involves also the use of heavy, large equipment operating on natural floors and in confined spaces. Such operations are required to be carried out under artificial light. Much of the easier won coal, that is the shallower coal, from this State has already been extracted and in future workings will be required to go deeper. As the depth increases strata pressures will increase, gas production is likely to be greater and the production of dust will also increase. A further problem which has not yet reached significant proportions in Australia is the potential rise in working temperature. This will be occasioned not only by the use of large items of equipment which themselves generate heat, but due also to thermal gradients as the depths increase. The need for better employee training is now being widely recognised throughout the industry. Under present highly mechanised conditions new employees should not be required to work with or near heavy mobile machinery without proper training

Jan 1, 1976

My early experience with the coal industry was in the latter half of the 1970s, where attention to only ones own æaccidentsÆ and concentration on behaviour controls were impeding the introduction of effective engineering controls such as ROPS, FOPS, roof support and residual current devices. Lack of the broad picture of personal damage and of relevant veridical (true saying) knowledge and data had to be overcome to achieve progress in reducing fatalities. Thirty years on, it is again necessary to take stock. How good is our knowledge, our data, our information on which we make decisions. Despite Australian all industry 1992-93 data showing 80.5 per cent of costs came from occurrences which permanently altered peopleÆs lives, New South Wales is still the only state reporting permanent disabilities. In 1991 - 1992, the rate of permanent disability per 1000 wage and salary earners was two. In 2000 - 2001, it was over four û more than doubled. Also strongly motivating is the huge cost. Industry carried 25 per cent of the $34.3 billion costs for 2000 - 2001, up ten per cent of 82.8 billion if the costs of pain, suffering and early death are included.

Jan 1, 2005

In the mid-1990s, after a long period of antipathy between the company and its detractors, Rio Tinto embarked upon an ambitious cultural change program that sought to transform the fundamental basis of its relationship with global, national and local stakeholders. This has evolved into a broader pursuit of positive cultural change within Rio Tinto as part of the mining industryÆs Sustainable Development initiative. Initially driven from the top down, the communities component of this program comprises an architecture of policies, value statements, social research and verification systems. The commitment to better community relationships is best exemplified in Australia by the scope and scale of the GroupÆs Aboriginal land access agreements, community development programs and the work of the Rio Tinto Aboriginal Foundation. While collectively these form the core elements of an evolving set of internal social competencies, development of second-tier competencies is required to organically embed a culture of sustainable relationships with local and regional communities. Second-tier competencies will include appreciation of social dynamics, social science and diversity at middle management level; rigorous social research that properly informs development options for companies and host communities; career paths and recognition within the mining industry for young professionals both generally and from stakeholder communities; proper community-needs assessments, research into such things as purchasing power and other economics data, and inventories of public goods such as land-carrying capacity and water availability. Without this information it is difficult to gain an appreciation of and to alert people to the consequences of change brought on by a mine. The next decade will see second-tier social competencies promoted within successful mining companies. Measures to achieve this include a range of Human Resource (HR) incentives such as recruitment and career advancement based on broad competencies rather than narrow technical proficiency, humanities training for mining professionals and performance rewards that recognise social competence. A sustainable future for mining in a globally connected social landscape requires selection of people who can listen, relate and act in an open social system. The challenge for the mining industry, its professional organisations and educational institutions is to acknowledge this and develop these new aspects of mining industry professionalism. This cannot be left to individual companies if the industry is to have a sustainable future.

Jan 1, 2002

By J P. Hsi

Recent increase in the development of underground space in urban areas in Australia has included soft ground tunnel construction. The ground movements associated with soft ground tunnel construction may present risk to other existing and proposed structures in the nearby vicinity. Much experience has been gained both in the UK and Asia in recent years in the engineering evaluation of this risk. The paper presents a procedure to assess these aspects of soft ground tunnel construction with reference to recent projects.

Jan 1, 1999

By B Snook, G Rollinson, R Fairhurst, R Herrington

Nickel laterites constitute a significant proportion of the worldÆs Ni reserves and are considered environmentally friendly alternatives to traditional sulfide resources. Subsequently they are of increasing significance for exploration and production. To be successfully exploited, however, they require an understanding of the relations between mineralogy, texture, grade and recovery. The development of automated quantitative mineralogy can aid in the characterisation of the ores to help improve extraction and processing methods. Recent developments in hydrometallurgy have resulted in relatively straightforward recovery of Ni in silicate (saprolite and smectite) ores. However, the extraction of Ni from limonitic ores is more complex. It requires a detailed understanding of the iron-hydroxide species and other, potentially interfering, oxide and hydroxide compounds. Particularly the relations between the Ni-bearing goethite and Mn, Al and Cr may adversely affect the economic prospects of an ore. Manganese can adversely affect the selective recovery of Ni and Co from solutions but has also been highlighted as a significant potential by-product (cf, Zhang and Cheng, 2007). Aluminium hydroxides can be significant acid consumers leading to an increased expense of extraction (Johnson, Cashmore and Hockridge, 2005). Chromite is resistant to acid attack, but chromium in goethite may adversely affect the dissolution leading to a retention of Ni (McDonald and Whittington, 2008). This study presents an investigation of oxide and hydroxide species in laterites using QEMSCAN« EDS/SEM-based automated quantitative mineralogy. Samples were collected from Turkey (¦aldag), Albania and the Philippines. Particular emphasis has been placed on the development of a quantification for Ni-poor and Ni-rich goethite.

Jan 1, 2008

By L Lagoeiro

The samples studied in this paper were derived from the iron oxide facies of iron formations (IFs) of the Quadrilßtero Ferrffero, south-eastern Brazil. The rich-iron oxide varieties of the IFs can be regarded as Fe-O systems because they consist predominantly of aggregates of haematite and magnetite crystals. The study was based on carefully selected samples in which magnetite crystals occur as isolated large crystals set in a matrix of haematite grains. Optical microscopy and an electron microscope equipped with an electron backscattered diffraction (EBSD) system were used to investigate the microstructural and crystallographic relationships involved in the phase transformation between magnetite and haematite. The magnetite crystals in the IF samples are partially transformed to haematite and this process is also known as martitisation. This transformation occurs along the crystallographic planes {111} of the magnetite producing a characteristic triangular pattern of interlocking lamellae of transformed haematite crystals that are oriented parallel to octahedral plane {111}. This new generation of haematite is referred to martite because of the martitisation process. EBSD analyses show that the magnetite and the new haematite crystals, martite, share crystallographic planes of highest atomic density, eg {111} and (0001), respectively, possibly due to the ccp and hcp atomic arrangement of the two crystals. Stereographic projections of these two planes therefore coincide when the maxima of their poles are plotted. However, the crystallographic orientation of the haematite crystals in the matrix shows maxima of (0001) poles that do not coincide with those of {111} planes of magnetite. Consequently, it is concluded that the direct transformation to haematite crystals retains the crystallographic orientation memory of the former magnetite crystals, possibly due to the similar manner whereby their atoms are packed together in the crystal structures. On the other hand, no such relationships are observed between magnetite and haematite crystal in matrix. This suggests that haematite grains in the matrix may have been formed by other processes rather than those involved in the iron oxide transformation observed within the magnetite grains.

Jan 1, 2008