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By Ennis P. C

The Mt Keith ultramafic intrusive extends for about 200 kilometres from Agnew in the south to Wiluna in the north. It forms the host for a number of nickel sulphide orebodies including Mt Keith and Honeymoon Well. Long fibre minerals are associated with the orebodies. The presence of these minerals impacts on the issue of tailings disposal from several standpoints, particularly the slurry beaching properties and dust generation from dry beaches. Central thickened discharge (CTD) is an innovative method of tailings disposal that involves stacking tailings in a low conical hill instead of storing them in cells. In appropriate circumstances this leads to savings in capital costs and operating expenditure. The method was introduced to Australia in 1981, and is currently employed at four operating mines, Elura and Peak Gold, both at Cobar in NSW, McArthur River in the Northern Territory, and Union Reefs near Pine Creek, also in the Northern Territory. It is the proposed method for Century Zinc and Ernest Henry, both in Queensland. The paper describes laboratory test work and design parameters for the application of the method to tailings disposal at Honeymoon Well and compares them with comparable data for other CTD systems. Of particular relevance for design purposes are beach slope, density, and water recovery. Wind tunnel tests were conducted on the Honeymoon Well tailings samples to investigate dust generation from the dry beach surface and it was concluded that dust generation from an undisturbed beach would not occur because of crusting.

Jan 1, 1996

It is always difficult to sum up an open forum adequately and instantaneously, so, with the privilege of hindsight, and also with some time to reflect, I am exercising the Chairman's prerogative to put together my view of the overall conclusions. Hopefully, these may provide a focus for each Institute to formulate its own programme with respect to mineral industry education. First, in answer to the question, "Should there be Schools of Mines?", there was a very clear 'yes'. However, I reiterate what I said in the introduction to this forum, specific professional education for the mineral industry exists only because the mineral industry sees a need and wants it. If the mineral industry should decide that it does not need professionals with specific mineral industry training, then such training will cease to exist. As alluded by Dr Hackett, if such training ceases to exist, one must then question the need for Institutes of Mining and Metallurgy. Now, there's some food for thought! Specialist schools of mines (metallurgy and geology) can only exist in an environment of genuine interaction with, and support by, industry. For their part, schools of mines, used here in a generic sense, require leadership that is strong but responsive to industry needs. It is the leader that puts his stamp on a school, and, to a large extent, determines whether that school is 'good' or only 'mediocre'.

Jan 1, 1986

By Ranklin W. J, Swinbourne D. R

Lead blast furnace slags contain typically 10 - 20 mass per cent Zn. The zinc can be recovered by slag fuming, in which a powdered coal/air mixture is injected into a molten slag bath. Volatilised zinc is recovered as zinc oxide from the gas and processed hydrometallurgically to produce zinc metal. The ISASMELT continuous lead smelting process in operation at Mt Isa produces a slag containing about 12 per cent Zn which is currently granulated and stockpiled. This slag could flow to a further bath-smelting reactor for continuous zinc fuming. Rather than collecting the zinc as fume from such a process, one option would be to recover it using a lead splash condenser. The success of this operation would depend on the composition of the gas produced, in particular the concentrations of gases capable of reoxidising zinc vapour, viz, carbon dioxide and water vapour. The aim of this investigation was to determine the smelting conditions for a bath-smelting process such as ISASMELT or SIROSMELT which would produce a gas similar in composition to that from an Imperial Smelting Furnace by thermodynamic modelling of the process using the CSIRO Thermochemistry System. It was found that such a gas could be produced if coal injection and oxygen enrichment of the combustion air to at least 40 per cent 02 were used. However, the off-take gases must be conditioned by addition of methane to reduce the water vapour content to acceptable levels. An addition rate of ten per cent of the off-gas flowrate was found to be adequate. Addition of methane to the off-gas had the added advantage of cooling the gas from the bath temperature to a temperature suitable for normal lead splash condenser operation.

Jan 1, 1993

By Kupper T

Firstly, electric analog models are discus- sed to show fluid streaming conditions. In these models the depth of blast at tuyere level, the height of the bath, the influ- ence of different angles of the furnace zones and the different possibilities of the root of the cohesive zone have been changed. Tests to define the influence at a large blast furnace are given. Secondly, the wear of carbon bricks in the hearth is examined under the influence of gas, slag and pig iron. Oxidation tests in a special scanning microscope with the pos- sibility of heating and gas treatment are shown. Wear mechanisms are discussed fora large blast furnace and proposals for im- provement are given. Finally, the possib- ilities and value of the temperature meas- urement in the hearth block are discussed.

Jan 1, 1981

The narrow quartz vein deposits at Konongo and Ghana Main Reef gold mines in Ghana were emplaced during the plastic flow cross folding of pre-existing sub-isoclinally folded volcanic and perivolcanic deposits of Proterozoic age. The older fold structures tightened differentially according to their position in relation to the axes of the cross fold pattern giving complex outlines to the reefs in both plan and cross section.Some 4500 measurements of bedding plane linears were used in the resolution of the Boabedroo footwall structure at Konongo. The methodology developed at the Boabedroo mine was then successfully applied to other complex bodies at the Konongo and Ghana Main Reef mines.All mine development, especially stope preparation, of the folded quartz reefs at Konongo and Ghana Main Reef was controlled by the geologist to ensure that the veins were removed with as few geologically enduced hiccoughs as possible.

Jan 1, 1993

The discovery of gold mineralization at the Manhattan mercury mine, Napa and Yolo counties, California in 1978 was the result of applying a new exploration ore deposit model in a region previously unprospected for gold. This discovery, the McLaughlin gold mine, owned and operated by Home-stake Mining Company, is a classic epithermal mercury-hot springs-gold deposit currently producing approximately 7,776,000 grams of gold annually.The exploration program that led to this discovery was based on a mercury-hot springs-gold genetic model. The model was developed using basic knowledge of ore-forming processes plus careful field observations made during examination of many known precious metal districts in. the Western U.S.A. Theoretically, hot spring systems could host gold deposits and, indeed, gold in these environments had been recognized for years. However, at the time of the McLaughlin discovery, it was not known to occur in sufficient quantities to inspire geologists to explore hot spring systems specifically for gold. Field observations recognized the presence of hot spring deposits and mercury mineralization asso-ciated with precious metal districts, (Bodie, California being a type example), and this associ-ation prompted the development of a hypothetical model. Subsequent exploration activities were directed towards the examination of mercury mines and prospects as potential targets for gold deposits. The model envisioned hot spring deposits (sinter) containing mercury mineralization at the surface with anomalous gold values grading downward into significant ore grade gold values.

Jan 1, 1990

By Kikuta K

ISP (Imperial Smelting Process) produces zinc and lead simultaneously from zinc and lead sulphide concentrates and recovers copper and precious metals into a lead bullion. The strength of sinter is important to keep permeability in the shaft of the Imperial Smleting Furnace. The residual sulphur content of the sinter is also important as it causes metal losses into slag. The paper describes an investigation into the sintering operations to improve sulphur elimination and sinter strength. The micro structure of the sinter and the effect of the blast rate, sintering temperature etc have been studied.

Jan 1, 1993

Statistics show that despite a low lost-time accident rate there is a high fatality rate from falls of ground in pillar extraction work. Investigation of accidents indicates that in many cases the planned ex- traction cycle has been ignored. Better training, supervision, and personnel protection and where possible changed systems are suggested as a means of improving safety and achieving better Results.

Jan 1, 1974

By Burman B. C

This paper describes studies into two particular aspects of the Lochiel deposit which formed part of feasibility level geot2chnical and hydrogeological investigations for proposed open cut mine development. The two aspects were depressurisation of thick beds of silt located through the profile and the determination of characteristics and origins of soil structure and their effect on pit stability. The studies were very detailed and multi disciplinary and highlight the integration of geology, geotechnics, hydrogeology and mining that is required for mine development studies. It is considered that as more marginal deposits are developed throughout the world the demands for efficient economic mining together with in- creasing scales of operation will require simi- lar types of studies. As such the studies pre- sented herein are likely to be a forerunner to a,emerging trend for development of open pit mines in difficult ground and water conditions.

Jan 1, 1986

By Semple DG, Leach TM

A continued exploration programme has further defined the geology of the Tolukuma vein system, verified the resource indicated by Newmont, and identified potential for additional mineralisation. The resource at Tolukuma Hill, designated as Zone C, is a measured 440,000t @ 17g/t Au and 46g/t Ag with an additional indicated resource of 120,000t @ 16g/t Au. A diatreme breccia localised at an intersection of structures, and a relationship of gold to base metal sulphides, are highly indicative of a porphyry association. Typical epi-thermal features such as crustiform banded quartz and quartz pseudomorphing. platy calcite are also present and locally contain lesser gold mineral-isation. Pre-existing dilatant structures have acted as a host to the ore fluids, resulting in the formation of the semi-continuous Tolukuma-Gulbadi veins over a 1100m strike. A fluid flow model suggests that mineralising fluids were sourced from the diatreme margins and migrated laterally along dilatant structures. Bonanza gold grades are derived through fluid quenching in the flexure between a hanging wall split which hosts much of the Tolukuma Hill resource and the feeder graben structure. Thus, the relationship between the pre-mineral structural geometry and fluid upflow at the margins of a diatreme breccia, controls the ore setting. Potential for more ore remains within the Gufinis and the 120 veins as well as in the outlying Prospects.

Jan 1, 1994

Modern plate tectonic reconstruction of Mexico and Central America shows that the southeast-extend ing Precambrian backbone of Mexico, together with the east-flanking accreeted Huastecan (Appalachian-Caledonian) orogenic belt, are geotectonic elements practically absent in Central America, except west-ern and northern Guatemala and Belize, and contrib-uted little to the mineral potential of the entire region.The gradual accretion of the Cordilleran oro-genic belt took place against the western-south-western margin of the Precambrian backbone, and its consolidation required several tectonic events from the medial(?) Paleozoic to the end of the Mesozoic. The striking features of this "long-lived" orogenic belt are the massive sulphide min-eralization in the upper Paleozoic eugeoclinal as-semblage, the widespread gold occurrence in quartz veins in the lower Mesozoic volcanics and related intrusives, the carbonate-hosted silver-bearing lead-zince deposits of the Mississippi Valley-type (or Pine Point-type) around carbonate banks within the Lower Cretaceous back-arc miogeocline, that de-veloped over the Precambrian backbone and deeply-eroded Huastecan orogenic belt, the massive sul-phide (Pb-Zn) deposits in the Upper Jurassic-Lower Cretaceous sequence, transitional from miogeocline to eugeocline, which carry high grades in silver, and the iron deposits in this transitional facies, which are described in the literature as related to dioritic intrusives of Late Cretaceous age. Central America, south and southeast of the Mota-gua-Polochic fault system, forms part of the in-ternal zones of this orogenic belt.

Jan 1, 1990

The conventional approach to the disposal of fine coal mine tailings, which involves piping the tailings as an aqueous slurry to a storage where they remain in the form of a permanent wet deposit, is becoming unacceptable. This approach is a legacy of a "contain and forget" mentality, which has economic advantages only in the short term. In the longer term, wet tailings deposits occupy large areas of land and present extreme rehabilitation difficulties. Alternative tailings disposal systems, which are sustainable and which facilitate rehabilitation, are required. The possible alternatives include the mechanical dewatering of fine tailings prior to disposal in combination with coarse reject, tailings disposal into spoil pile valleys, and the combined pumping to disposal of tailings and coarse reject. The most appropriate choice of fine tailings disposal strategy will vary from mine site to mine site. The chosen strategy should be optimised to meet increasingly stringent environmental requirements, within the constraints imposed by each mine. The alternative approaches represent significant departures from past practices, and require considerable industry driven research and development before they can be adopted with confidence. All three alternatives involve mixing of the fine tailings and coarse waste streams, aimed at creating a mixture of reasonable engineering properties. Understanding the engineering behaviour of such mixtures is central to the success of these alternative disposal strategies.

Jan 1, 1991

By Kennewell G. J

This paper aims to present the evolution of the mining method in the Prince Lyell orebody. Initial strategy and practical experience are detailed as are the reasons for and benefits of changes to the method since 1972 when underground mining began. This section of the paper starts with ten series and concludes with 40 series which was completed in 1989/90.In addition, to update the series of papers written by various authors over the past ten years on Mount Lyell, a review of the experience in the current 50 series lift of mining will be given. As well, the basic planning guidelines are discussed for 60 series - the final lift of the Prince Lyell orebody.

Jan 1, 1992

By R G Warren

Sparse geochronological data have been combined with data on felsic suites and depositional facies of rocks to provide an overview of the development of the Arunta Block. The study provides a basis for construction of a map showing the distribution of granites and associated felsic extrusive rocks in the Anmta Block. The tectonic evolution can be subdivided into a series of significant time intervals. Only in the initial stage, to about 1880 Ma, was there any subduction-related magmatism. All later felsic magmas were crustal-derived melts. The early, pre-1880 Ma arc-related units in the SE contain small showings of Cu, probably including the small Cu deposit in the Casey Bore Inlier at the edge of the Simpson Desert. The most significant time-interval for formation of mineral deposits was 1820-1760 Ma, when volcanogenic Cu-Pb-Zn deposits formed in the Strangways Metamorphic Complex and also in the Jervois district. Stratabound tungsten lodes in the hanging wall of

Jan 1, 1994

By Carthew SJ

The early period of South Australia's mining history was dominated by Cornishmen as large numbers of miners and their families migrated to escape closure of the Cornish copper mines. Records show that Carthew families migrated from Kent and Cornwall to South Australia. Those from Redruth, Cornwall, were miners and their family history provides an insight into the condi- tions under which early miners lived and worked. Carthews are one of the oldest surviving mining families in South Australia and their movement pattern has been typical of many other early Cor- nish mining families.

Jan 1, 1987

It is my role at this juncture to report to you on behalf of the Council of Mining and Metallurgical Institutions itself. In essence, the Council is an orbital body - a little like Halley's Comet - it returns to earth, in spectacular style, once in every four years. We must acknowledge, however, that the spectacle is provided by the constituent member body organising the particular event and, on this occasion, it is The Australasian Institute of Mining and Metallurgy. On behalf of the Council and its other constituent bodies may I thank the Australasian Institute most sincerely. Our thanks go to Sir James Foots, the President of the 13th Congress, and to all the members of the organising committee and to the five sub- committees. Over 40 people are involved as full members and I am certain there will have been many more involved in very meaningful ways. None of this great- team would ask me to mention them individually, I'm sure, but to fail to acknowledge the role of John Funnell, the Honorary Secretary, would be an unforgivable omission. We must also thank the kindred institutions in Japan, Korea, Thailand, Malaysia, and Indonesia who all helped with the tours themselves or with the initial preparations. Qantas, Jetabout Australia, and Jetabout Singapore have all also made very important contributions and, in our different ways, we each owe our thanks to them. At the two most recent meetings of the Congress - in Hong Kong and Johannesburg - Professor Marston Fleming made this report on behalf of the Council and was supported on both occasions by Robert MacWilliam as vice- chairman. Marston died in 1983 and Robert died in 1984; both men contributed a great deal to CMMI and we will miss their counsel for a long time. As you know, Sir Alistair Frame succeeded Marston Fleming as chairman in 1984 and I succeeded Robert MacWilliam as Vice-chairman.

Jan 1, 1986

By J Johansson, J Lööw

There are many reports about how the new technology will affect our work, sometimes they are utopian but often dystopian. Most of the visions describe the industrial work, while the work of the managers does not seem to be affected. In this article, the authors will discuss how the new technology within the concept of Mining 4.0 changes the conditions for leadership and the work of managers in a modern mining industry.

Sep 1, 2024

By Weller KR, Lim IL

The high pressure grinding rolls is one of the few new comminution devices that offer substantial savings when compared with traditional crushing and grinding circuits and with SAG milling. The machine has been well accepted in the cement industry, but mining companies have been more cautious in adopting this technology, partly because of wear and availability problems, and partly because of uncertainties in designing circuits which will deliver the power savings without complicating downstream processing. This paper addresses the latter problem by providing a model structure for predicting power draft and throughput from measurements made with small pilot scale high pressure rolls. Three existing models for predicting product size distributions are assessed and suggestions made for future work. The model structure comprises a power equation, incorporating measurements of torque and rolls speed previously used by the authors. Transport through the mill is assumed to be plug flow. Throughput is governed by the equilibrium gap between the rolls, which is determined both by machine settings and the physical properties of the feed material, including its size distribution. Therefore some form of physical testing in a model machine is required to determine throughput parameters. Results from copper and nickel ore experiments covering a wide range of machine conditions are presented and compared with model predictions. Model assumptions are discussed and directions for future work Suggested.

Jan 1, 1993

By R Ulusay

Rock mechanics involves characterizing the mechanical properties and behaviour of rock material and the natural discontinuities of the rock mass, while rock engineering is concerned with specific engineering circumstances, for example, how much load will the rock support and whether reinforcement is necessary. Rock engineering models developed depend considerably on the input data such as boundary conditions, the properties of rock material and rock mass. Correct evaluation of these properties frequently requires laboratory and in-situ tests, supplemented with a high degree of experience and judgment. Accordingly, since 1974, the ISRM Commission on Testing Methods has spent considerable effort in developing a succession of the ISRM Suggested Methods (SMs) for different aspects of rock mechanics and rock engineering with the contribution of a number of working groups and cooperation of some other ISRM Commissions. This paper emphasizes the need and importance of standardization of rock testing methods within the context of the ISRM SMs, gives a guideline for developing ISRM SMs and finally discusses on some implementation and contractual issues associated with rock testing and experienced in practice, and briefly introduces main future trends in rock characterization, testing and monitoring. This is an extended abstract only. CITATION:Ulusay, R, 2018. Standardisation on rock characterisation, testing and monitoring with emphasis on ISRM suggested methods, practical issues and difficulties, and future trends, in Proceedings The Fourth Australasian Ground Control in Mining Conference (AusRock), pp 17–18 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 30, 2018

By I Levy

At our Monkland Mine at Gympie, we operate a deep, narrow vein gold mine using hand held equipment, rail mounted haulage and narrow shafts. This is in many respects the old-fashioned way and is well suited most of the orebody geometry exposed to-date. We have also commenced some long hole stoping and we use alimaks for some jobs. The heart of our particular mining style is the employment and retention of experienced miners with remuneration based on productivity. We do our planning/monitoring/supervision down to the level of daily individual productivity. In focussing on cycles per se, we have chosen not to talk about drill and blast cycles or cycles for mine development, stope preparation or drawdown and haulage. Instead we have stepped right back from the operation as presently run and have adopted a very broad view of the mining cycle. We will in this presentation intertwine the ebb and flow of, exploration, project sponsorship, development, production and cash returns to owners. The time line considered spans both history and predicted future.

Jan 1, 1998