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Drilling at Ipswich during the last twelve years by the Queensland Department of Mines has proved large quantities of reserves which have assured the security of the field for many years to come. This is perhaps the greatest contribution to the development of the field since its discovery in 1827.The drilling campaign commenced in 1950 and by the end of 1961 comprised 242 holes totalling 180,220 ft.Intersections of formations and seams, accompanied by detailed surface mapping, led to more precise knowledge of the geology of the field than was previously possible, and clarified many problems of correlation. Productive formations are part of the Middle Triassic Ipswich Coal Measures, a 4,300 ft sequence of fresh-water sediments with some interbedded volcanics. They are overlain by the Upper Triassic Bundamba Group and the Lower Tertiary Booval Group.Reserves disclosed by drilling amount to 171,487,000 tons, comprising 109,407,000 tons "measured" and 62,080,000 tons "indicated". The security of these reserves encouraged many collieries to instal modern efficient mining machinery and washing plants.The climax of recent development of the resources of the field will be the commissioning in 1966 of a £33 million 360 MW power station in the Swanbank district which will consume 14 million tons of coal during its 30 year life and will have a peak demand of some 20,000 tons per week.Drilling is continuing and is expected to prove additional reserves which will justify further development of the field.INTRODUCTIONUntil 1949 there had been no concerted effort to test systematically the resources of the whole Ipswich field. Fifty two known holes totalling 30,500 ft had been drilled, eight of them by the Department of Mines, but because of poor core recovery and inadequate records most of them were of little use in a comprehensive assessment.Development of the field was being retarded by uncertainty regarding reserves and by the general state of the coal mining industry. Numbers of comparatively small independent companies and owner groups were operating coal...

Jan 1, 1963

A discussion on simulation tools to aid the development of robotics platforms is presented. The focus of the work is towards mining robotics platforms where operations are typically in unstructured, unpredictable environments and a high degree of dependability in their operations is required. It is argued that a test-based development approach leads to more robust solutions and faster development cycles than traditional single-track field-only development and that the key enabling technology for this development paradigm is the judicious use of simulation tools. The future direction of simulation for use in online applications such as active planning and as a means to assist tele-operation in high latency communication applications is also brief y considered together with the requirements for a useful simulation environment in terms of the simulator architecture. Finally, a case study is presented on the application of the discussed methodologies to an unmanned ground vehicle (UGV) for earth-moving tasks, which is being developed in an accelerated time frame with a transient development team.

Dec 6, 2010

Permian coal seams from the Tomago Coal Measures in the Northern Coalfield, New South Wales, were analysed petrographically and reflectance measurements made for each. Vitrite contents were moderate to high for most of the coals but for two they were very low.The mineral-matter contents were low to moderate by Australian standards. Different profiles of a particular seam could be correlated by petrographic methods.Standard seam profiles were drawn up and from these an idealized Tomago seam sequence was compiled. All the coals were of high-volatile bituminous rank. Their carbon contents, but not thcir reflectances, varied significantly with the quantity of vitrinite present.

Jan 1, 1968

By D N. B Skinner

Changes in the configuration of late Cenozoic volcanic arcs related to Pacific-Australian plate convergence in northern New Zealand may have localised large-scale epithermal gold-silver mineralisation to a particular part of the volcanic arc system, the Coromandel Volcanic Zone (CVZ). The history of arc-type volcanism in northern New Zealand began with the development of the continental margin Northland Volcanic Arc from early-mid Miocene (26-15 Ma). From 18-15 Ma the Northland Volcanic Arc extended south into the northern and western part of the CVZ where it is dominantly composed of andesite with lesser dacite and very minor rhyodacite. In the south, centre and east of the CVZ, younger andesite-dacite volcanism overlapped in space and time (14-5 Ma) with voluminous rhyolitic volcanism associated with rift-hosted calderas and minor basaltic eruptions. This change to bimodal rhyolitic-basaltic volcanism and extensional tectonics was a result of southwest (SW)-directed propagation of the Colville-Lau oceanic island+ arc into the north-northwest (NNW) trending Northland Volcanic Arc and its underlying continental crust. The extensional tectonic regime created in the collision zone between the two arcs is also the site of the 14-6 Ma Coromandel epithermal gold-silver province, which contains some 50 separate deposits and has a production (1862-1996) of about 300 t Au and 1150 t Ag. Extensional tectonics facilitated the emplacement of silicic magma at shallow crustal level and led to reactivation of deep basement faults. The resulting enhanced heat flow and fault-focused fluid flow localised large hydrothermal systems and associated extensive low-sulphidation epithermal gold-silver deposits in the southern part of the province, as at Waihi, Golden Cross and Karangahake.

Jan 1, 1997

Support design in jointed or blocky rock masses is often approached by the use of either 'rules of thumb', rock mass classification systems such as the Q-system (Barton, Lien and Lunde, 1974) or RMR (Bieniawski, 1973) or conventional wedge analysis. Generally, this requires that a number of key simplifying assumptions are made and the support system is designed to cater for either a mean, most likely, or worst case scenario depending on the risk tolerance. The design block size is often a major uncertainty and often a worst case block size based on excavation span is used. Thompson and Windsor (2007) state that it is inappropriate to base support designs on the excavation size as these size blocks rarely occur if discontinuity trace lengths are considered. Probabilistic keyblock methods can be used to determine the most likely design block sizes. A methodology is presented whereby JBlock software (Estherhuizen, 1996) is used to estimate potential block sizes as part of the support design process. Using information such as the spacing, orientation and length of discontinuities, it is possible to simulate blocks in the walls of an excavation (Esterhuizen and Streuders, 1998). Keyblock analysis methods (Goodman and Shi, 1985) are used to evaluate whether blocks are removable and whether the chosen support will be sufficient to ensure stability. Data from two mines is used to demonstrate how probabilistic keyblock analyses can be used in support design. Discontinuity data was used to generate 10 000 removable blocks and the design block size statistics were determined. For one mine this information was used to scale blocks in a conventional. Unwedge analysis whilst for the other mine, the point estimate method (Harr, 1987) was applied. The choice of appropriate design acceptance criteria in terms of factor of safety and probability of failure is also considered.

Nov 25, 2010

Northern Iron Ltd (NIL) is an Australian listed company that recently brought the historic Sydvaranger open pit Magnetite Mine (the Project) in Northern Norway successfully back into production. NIL made the decision to operate the Project on an owner mining basis, due to limited large scale mining expertise amongst Norwegian mining contractors, a long mine life, a limited range in planned mining rate and to minimise costs. As a new mine operator in a country where labour practices are strictly regulated, there was the desire to reduce the risk associated employing and managing skilled personnel. This was achieved by coupling the purchase of the required mining equipment from the original equipment manufacturer's (OEM) regional dealers with OEM supported Maintenance and Repair Contracts (MARC). This paper examines the process that was followed to implement an owner mining operation in a short time frame; approximately 12 months from the initial requests for quotation to actual delivery of mining equipment to site, and some of the challenges faced. By following a formal and well-tested process, not only was the implementation achieved in the set time frame, but significant value was added through the cost savings achieved in the equipment purchase price and MARC rates that were negotiated through this process.

May 1, 2010

The Macraes Mining Company Limited was listed on the New Zealand and Australian stock exchanges in January 1990, and the proceeds of the float were used to purchase a 70 per cent interest in the Macraes Gold Project, previously owned by BHP Gold Mines (NZ) Limited. Macraes Mining has had a 30 per cent interest in the project since May 1984, when it was incorporated. Project financing in the way of a gold loan was secured in February 1990 and construction commenced shortly afterwards. The mine construction activities were completed within nine months and the mine commenced operations in October 1990.

Jan 1, 1991

In November 1999 Waihi Gold Mining Company commissioned its new crushing and conveying plant used to transport both ore and waste from the Martha Mine to its ore processing plant and also its tailings dam construction area. To date, a record monthly throughput of 854 000 tonnes throughput has been achieved. This paper outlines the measures taken subsequent to the commissioning of the system to achieve greater than design throughput and to mitigate the environmental and safety issues associated with operating the system in the middle of a town.

Jan 1, 2001

The extent of regional stratigraphic and structural geological mapping so far carried out in Australia is likely to be greatly overestimated by uncritical inspection of the latest authoritative geological map of the continent-that so ably compiled by the late Sir'T. W. Edgeworth David. Vast areas geologically coloured on this map are in fact known only from the most meagre field data, some of Which even include observations of distant views from which the so-called "geology" has been indicated in' reconnaissance reports.This applies to large areas in Cape York Peninsula; the plateau of Arnhem Land, and its margins except on the west where the Pine Creek mineral belt is better known; to the Desert Basin of Western Australia, practically the whole of the western half of the Northern Territory, much of east-central Western Australia, and northwestern New South Wales. Other vast areas are, more happily perhaps, left blank. It is true that prospecting parties have, at various times and with varying degrees of thoroughness, traversedparts of these little-known regions, often, however, in the search for gold or the.more obvious types of metalliferous mineral deposits and, furthermore, too often without leaving any written account of their examination, or with very sketchy details supplied. Unpublished geological surveys also cover some parts of these regions, but, on the whole, the picture we can draw of the regional deployment of rock masses in Australia is far less full than even David's map, with its obvious blanks, presents to us.Lest the practical mineral seeker among us should be inclined to place too much reliance on the prospecting to which I have referred.as giving him a straight hint of what country to keep out of, we may point to the recent discovery of a major sedimentary basin in the east KimberllilYs on which Dr. Teichert will have more to say. And that there are new metalliferous mineral deposits to be foundin parts of these little-known areas no one can doubt, for, after all, new discoveries are made from time to time in areas so well-known as the Victorian gold-fields. I take it then that regional geological mapping is a necessary concomitant of the further development of Australia's mineral resources-but I am not of the school that places it first on the list of priorities, and furthermore I believe that there can be a royal road to regional mapping-an inspired approach based on knowledge already gained and led to fruition by field surveys in key areas, by which there may be obtained a result giving a significantly close approach to actuality with only a fraction of the work that would be required for detailed field surveys on a systematic basis. I believe that a policy of rapid reconnaissance of such a type should be adhered to, especially in view of present deficiencies in numbers of geologists available for all purposes in Australia. The details that must eventually be sought can, I believe, be filled in later as the whole country becomes more developed and amenable to detailed surveys.

Jan 1, 1950

By McLennan R. G

The principle of personal safety is as old as the human race. The application of this principle to industry is of much more recent origin, and may be said to be almost exclusively the product of the twentieth century. The enormous strides in technique and production mode prior to the turn of the century had been achieved without any real regard for the crippled human by-products of that expansive era. It was accepted that. accidents were inevitable and formed part of the price that must be paid for production. It was not until 1885 that the first Workmen's Compensation Act was passed in Germany making the employer financially liable for injuries suffered on his plant.With awakening social conscience came the first organised efforts to reduce accidents in industry. Early 19th century literature dealing with the development of powerdriven machinery and the growth of industry in Europe contains many references to the unsafe and unhealthy working conditions that accompanied the change-over from the home workshop to the industrial plant. By the year 1900, there were in Germany - and a little later in England governmental regulations dealing with the guarding of hazardous machinery. American industry, now the acknowledged leader in industrial safety, admits freely that when an organised safety movement commenced in that country, there was already a considerable amount of information available to them from European experience. The steel industry was well to the fore in this work, and in...

Jan 1, 1957

The reconstruction of the world after the present war must inevitably be profoundly influenced by the rise and progress of New China.The principle of Chinese mathrity has been admitted by Great Britain and the United States by their abjuration of extra-territorial tights, and by the withdrawal of the Maritime Customs Administration. The United States admits equality by her declaration that Chinese are eligible for American citizenship, and the reaction to this will be swift enmity to such peoples as may impose humiliating restrictions upon Chinese citizens.Finally, the decisions of the Moscow Conference and the recent meeting of National leaders in Cairo give partnership rights to this new State in post-war reconstruction, and open the way for a rapid realization of her destiny.It seems certain that China, if so she wills, can become, within a generation or so, one of the considerable forces of the world. The toad she wiII follow will be lighted by her own inherent and intrinsic genius. Her speed of progress can no longer be forcibly influenced by other nations and the attitude towards her of somewhat contemptuous patronage hitherto adopted by the European communities bordering the Pacific Ocean must be radically modified.It is doubtful whether the European will ever reach full understanding of Chinese mentality. The Chinese "way of life" since the dawn of her civilization has been totally divergent from that of the European, but the enormous potential strength, due to the simplicity of their requirements and their steadfast industry, is a function of that "way of life." On the other hand the trend of reorganization must obviously be towards Western standards; and a wide knowledge of the potential strength of the Chinese is possible and will be essential in our post-war world. The following, necessarily inadequate, notes are therefore offered, as an indication of the obstacles to be overcome and the capacity of the Chinese executives and operatives to overcome them.For 'thirteen centuries the political and social structure of China proper (ie, excluding Mongolia, Manchuria and Tibet) has been rigidly shaped by the philosophy of Lao Tze and the ethics' of Confucius. This Taoism, which is described as the "way of harmony" with its three jewels of character, gentleness, economy and humility, advocates the minimum of social, economic and political organization and still gives the key to the Chinese character.The Mongol and Manchu conquests of the 12th and 17th centuries, respectively, could hardly be dignified with the name of war, but the superior intelligence and harder mentality of the unwarlike Chinese finally absorbed...

Jan 1, 1944

The commonly used Stopes-Heerlen coal petrographic classification and nomenclature has over the years been subject to variable interpretations. This paper discusses the problem with specific reference to the inertinite maceral group. The effect of various interpretations of the Stopes-Heerlen system on maceral analysis is discussed and illustrated by means of comparative analyses conducted by a number of laboratories in Australia.An attempt is made to define the reflectance thresholds used by the authors to subdivide the inertinite group; the genetic and technological significance of these thresholds are compared.The difficulties of distinguishing structured and nonstructured macerals of the inertinite group are discussed in terms of possible improvements to the present StopesHeerlen system by extending the classification to include transitional maceral types.

Jan 1, 1970

Bio-Oxidation of Arsenic and Stibium Bearing Gold Ores Bio-oxidation of arsenic and stibium bearing gold ores with acidithiobacillus ferrooxidans was studied. The preoxidation results show that the best bio-oxidation technical parameters are the initial pH in the range of 1.8 ~ 2.0, particle sizes under 0.074 mm, temperature in the range of 25¦C ~ 30¦C and rotating speed of the orbital incubator in 100 rpm ~ 160 rpm. The leaching results show that If the ore, of which contain 10.37 per cent arsenic and 36.81 per cent stibium, is not bio-oxidised, gold leaching is only about 41 per cent, after 8 days oxidised, the result is about 76.55 per cent, which improved about 35.62 points. The relationship between gold leaching and arsenic oxidation is direct proportion, furthermore, it needs only partly oxidise and higher gold leaching could be get, for example, gold leaching is over 90 per cent when asenic oxidation is 60 per cent. The results will provide theoretical and technological supports of bio-oxidation arsenopyrite for pretreating refractory gold ores.

Sep 13, 2010

THE ore treated is almost pure copper pyrites (chalcopyrite) in a gangue of quartz and quartz-felsite. Very little free iron sulphide (pyrite) occurs, and at the time of the erection of the flotation plant the stopes in the oxidized zone had been almostentirely depleted. This zone only extends to a shallow depth, and, below the l00-ft. level, the sulphide for the most part is clean and bright but in the crushed and brecciated parts of the ore channel, where surface water has circulated freely, the gangue is decomposed and kaolinized, and the copper sulphide badly tarnished. This class of ore gave considerable trouble at the mill, but unfortunately, was very limited in quantity. A sample of rich ore assayed-Copper, 21.2 %; iron, 24:.3 %; silica, 28.9 %; sulphur, 25.1%.The concentration in the original mill was effected by handpicking, jigging, and tabling. A considerable portion of the copper mineral arrives at the surface in the form of large lumps of very pure quality, eminently suitable for sorting out by hand.The rich ore is tipped over a grizzly at the shaft bins; the oversize hand-picked, and the undersize bagged direct.

Jan 1, 1912

Some important mineral fields are referred to in discussing the formation of placer deposits in Australia.Testing methods include boring by hand, with percussion rigs, with auger and pit digging drills, and by vibro drilling.Sampling errors are minimized by the use of correct techniques and equipment for boring, sampling and sample dressing. A hypothetical set of data is used to demonstrate the final process of evaluation, and somerelevant taxation provisions are discussed.

Jan 1, 1966

By R Shaw, M Hidding

The design of primary sample cutters for high-capacity conveyors is critical to achieving a correct sample, both in collecting the sample and ensuring smooth sample discharge flow. Modelling usually occurs at the design stage and requires extensive experience to achieve the correct result. However, it is difficult to confirm the effectiveness of the cutter design until after installation. Even with high-speed video, confirmation of complete sample capture is difficult, especially if the material characteristics change over time. Recent investigation using discrete element method (DEM) simulation to model the flow of the ore into the cutter and observe how it interacts with the cutter has revealed some interesting design requirements not observed in the past. By including DEM modelling, the correct design and optimisation of the cutter can be more accurately determined prior to commissioning.CITATION:Hidding, M and Shaw, R, 2017. Modelling ore flow in the design of high-capacity sample cutters, in Proceedings Eighth World Conference on Sampling and Blending , pp 145–150 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2017

By the use of flotation tests it was confirmed that there are two functions of oxygen in sulphide mineral flotation. Sized samples of galena and chalcopyrite were sulphidized, washed free of excess sulphide ion, and then contacted with air-saturated water for certain lengths of time. The mineral was then transferred to a sealed laboratory flotation cell containing water with a known concentration of dissolved oxygen. Xanthate and frother were added and flotation continued for 1 min.Both the extent of mineral oxidation and the concentration of dissolved oxygen markedly affected the flotation of galena and chalcopyrite. The response to a change in either variable is dependent on the level of the other, but generally best flotation occurs with the maximum degree of air saturation of the pulp. Galena flotation is hindered by oxidation of the mineral beyond a small threshold amount but a similar effect for chalcopyrite was not observed...

Jan 1, 1967

By S C. Dominy

The grade of ore at Marvel Loch mine is directly related to the presence or absence of shear zones and quartz-sulfide-rich hornblende (¦ diopside) veining within areas of plagioclase alteration. An experienced geologist can identify these features in hand specimen. Practical rules have been developed to assist this visual identification. The structural sites and styles of alteration and veining most conducive to gold mineralisation have also been determined. The work has enabled a better understanding of the geological controls on mineralisation at Marvel Loch, and has clarified geological understanding for optimisation of grade control modeling, ore block mark-ups, and minimisation of ore loss and dilution during excavation. In addition to this, it has enabled a detailed understanding of mine scale structural controls, geometry and relative grade relationships.

Jan 1, 2003

The refractory nature of residual gold in Kalgoorlie calcines is caused by occlusion in dense pyrrhotite formed by fusion within pyrite grains during decomposition. Fusion of pyrite increases as the rate of heating exceeds the rate of sulphur expulsion. By controlling these rates in relation to each other in a fluidised system fusion is limited and an expanded structure is formed. The increased area presented to cyanide solution, and the decreased diffusion distance, makes gold more accessible for extraction. Gold extraction from expanded pyrrhotite, before oxidation for porosity, is comparable with extraction from fully oxidised calcines from Edwards roasters. A method is suggested for standardised comparison of cyanidation residues.

Jan 1, 1957

By J J. Laas, A J. S Spearing

Considering the capital outlay, running costs and inherent difficulties of backfilling operations at depth the benefits need to be clearly established, quantified and then exploited. Expansion of Vaal Reefs Exploration and Mining Company towards even deeper, highly faulted ground, and the process of establishing codes of practice for the management of rockfalls and rockbursts, required that a sound support strategy be formulated. This paper describes the derivation of an overall backfilling strategy on Vaal Reefs. Use was made of experience gained over some 12 years with backfilling. Numerical modelling was used to estimate potential benefits of backfilling the deepest mining areas still to be extracted. In exploiting a probably unique opportunity, two contiguous mining areas bounded by the same major geological structures, were compared. One was extensively backfilled and the other not at all. Shaft sinking through a backfilled stope added another dimension to the database.

Jan 1, 1998