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Black coals occur in most of the major sedimentary basins in Australia. In addition to the better known Permian coal occurrences of the Sydney, Bowen, Oaklands and Galilee Basins, coals of Permian age occur in the Arckaringa Basin in South Australia, the Bonaparte Basin in Northern Territory and the Collie, Perth and Canning Basins in Western Australia and the Tasmania Basin in Tasmania. Coals of Triassic age occur in the Ipswich Callide and Tarong Basins in Queensland, the Tasmania Basin in Tasmania and the Leigh Creek area in South Aus- tralia. Coal bearing rocks of Jurassic age occur in the Mulgildie Basin and Maryborough Basins in Queensland and in both the Queensland and New South Wales portions of the Clarence Moreton Basin and Surat Basins. They also occur in the Perth Basin in Western Australia. Rocks of Cretaceous age known to contain coal occur in the Styx, Maryborough and Laura Basins in Queensland, the Gippsland Basin in Victoria and both the Queensland and New South Wales portions of the Surat Basin. The coal measures have been deposited in a variety of sedimentary environments and the coals vary widely with regard to thickness, extent, banding characteristics, maceral and ash content. However, they are generally of low rank and most are suitable only for steaming.

Jan 1, 1975

Land is of extreme importance to citizens of Papua New Guinea and is fundamental to most of their customs and values. Because of this, matters to do with land cannot easily be separated from other matters to do with the community. Good relation-ships with landowners and the community surrounding a development are, indispensable ingredients that -must flavour and colour the entire ;operati on .

Jan 1, 1994

By M Saghaeian, M Zare, V Sheikhzadeh, R Hejazi

High-Pressure Grinding Roll (HPGR) is one of the efficient methods for increasing the specific surface area (SSA) of iron ore concentrate for pellet feed production. HPGR grinding mechanism implies that material should compressed between the two rolls, therefore layer of material must be able to resist required pressure for achieving suitable grinding conditions. In this study, by doing SSA increasing tests with pilot HPGR, the effects of silica reduction on SSA increasing results were investigated. For this purpose, HPGR tests were performed on an Iranian magnetite concentrate before and after reverse flotation silica reduction tests. Based on the laboratory test results, silicates have been concentrated in two fraction sizes of the sample comprises coarser than 150 microns in form of quartz and finer than 7 microns in form of iron silicates. These silicates have been effected on reduction of concentrate bed pressure resistance by creating a pasty and sticky mud. In this condition, HPGR cannot work properly and operation results are not acceptable. According to flotation silica reduction tests, with 90 per cent weight recovery, concentrate Fe grade is increased from 67.8 per cent to 69.5 per cent and SiO2 content is reduced from 1.98 per cent to 0.9 per cent and especially for lower than 7 microns fraction size, as a critical fraction, SiO2 content decreased from 4.45 per cent to 2.35 per cent. HPGR tests were performed on 8 per cent moisture in 4 N/mm2 specific force and according to the results after silica reduction HPGR operation conditions are optimised. Results showed that the working gap increased from 7 to 10.5 mm and specific throughput of material raised from 180 ts/hm3 to 250 ts/hm3 , and SSA increased by 300 cm2 /gr in a single pass.

Aug 24, 2022

The Highlands Region of Papua New Guinea has 3 major national highways. The locations of these national highways are shown in Figure 1. The Highlands Highway begins at Lae City on the coast and passes through the Highlands towns of Goroka, Kundiawa and Mt Hagen. It terminates at Togoba approximately 10km out of Mt Hagen town. The Enga Highway begins at Togoba and passes through the towns of Wapenamanda, Wabag and Laiagam. It terminates at the giant Porgera Gold Mine. The Southern Highlands Highway also begins at Togoba and passes through the major towns of Mendi, and Tari. It terminates at Koroba station, near the Hides Gas Field. Two separate Feeder roads intersecting the main highway service both the Kutubu Oil Project and the Hides Gas Field. These national Highways play a very important role in the development of Papua New Guinea. Goods and services are delivered to the bulk of the population of the Highlands Region using these highways. Heavy machinery and equipment for the mining and petroleum projects of Porgera, Hides and Kutubu are transported using these roads.

Jan 1, 1997

By N Esmaeili, M Saghaeian, L Hosseini, V Sheikhzadeh, R Hejazi

Ore roasting has long been used for beneficiation and assay upgrading of different ores. In this process, which is mainly used for sulfide ores, the ore is heated to a high temperature. More specifically, it is a metallurgical process involving gas-solid reactions at elevated temperatures. Some types of Iron ore are weak in magnetic properties. Hematite, goethite and limonite are classified in this group. Unlike magnetite, which shows strong magnetic susceptibility, these ores are hard to beneficiate through magnetic separation route. Many researches have focused on gravity separation and flotation routes for upgrading these ores and these methods have also been utilised in the industry. One of the methods to whose industrial application less attention has been paid is magnetising roasting in which the non-magnetic iron ore is transformed to magnetite which is further beneficiated through magnetic separation. In this study, magnetising roasting tests have been performed on one goethite sample in order to check the feasibility of using this method for this specific ore in industrial scale. It is worth mentioning that high intensity magnetic separation have been performed on this sample before but the achieved results were not promising. Results have revealed that through magnetising roasting magnetite content of the ore could be increased from 1.7 per cent up to about 25 per cent. FeO content of the feed sample was increased from 1.03 per cent up to around 9.25 per cent. Also optimum size distribution for achieving the best results in magnetising roasting for this sample has been determined through this study. The best results were achieved when the ore size was 0–10 mm. The effect of coal ratio, time and temperature on the process have also be studied. A coal ratio of 5 per cent, time of 30 min and a temperature of 850°C were determined to be the optimum conditions. Finally, the technical feasibility of utilising magnetising roasting for this specific ore has been confirmed.

Aug 24, 2022

By Abell RS, Wyborn D, Solomon M, Stuart-Smith PG, Henderson GAM

The two major massive sulphide deposits in the Silurian rocks of southern NSW, Captains Flat and Woodlawn, differ from classical Kuroko deposits in several ways, e.g. they lie on the flanks of felsic volcanic piles in volcano-sedimentary marine sequences, are relatively thin and large compared to individual Kuroko deposits, show prominent banding in lead-zinc ore, and contain arsenopyrite. Qualified stuctural and stratigraphic correlations of the various fault-bounded remnant Silurian sequences that host these deposits provide the basis for a new interpretation of the regional geological setting that also differs from that of the Kuroko deposits (Ohmoto, Tanimura, Date, Takahashi, 1983), and sheds further light on the distribution of volcanogenic massive sulphide deposits in the Silurian rocks of NSW.

Jan 1, 1987

Rio Tinto Iron Ore (RTIO) manages eleven mines in the Pilbara region, Western Australia. Three of these mines have previously or are currently mining black shale that contains varying amounts of pyrite. Several new deposits currently being evaluated and existing mines that may progress below water table in the future, will also encounter this waste material. The black shale presents not just an acid rock drainage risk but also a spontaneous combustion risk. This paper presents the black shale management strategy and provides an overview of the relevant activities undertaken by RTIO. The strategy can be divided into two components which firstly involve defining the risk and secondly involve managing the risk. The mineral waste management plan is used to identify specific mineral waste hazards by:geochemical characterisation of waste material,undertaking mine site specific risk assessments,characterising the receiving environment,identifying sulfidic boundaries in geological and mining models,quantifying the amount of sulfidic material in medium and long-term mine plans, anddesigning and sequencing black shale waste dumps. Once a mine exposes black shale the Spontaneous Combustion and Acid Rock Drainage management plan is used and the major activities are: regular site meetings with a representative from every group that works with black shale;compliance with safe working procedures for site specific and detailed activities;regular training;the use of specific explosives to prevent premature detonation;ongoing geochemical characterisation;acid water management, monitoring and analysis;regular internal and external auditing of procedures and practices; andclosure planning assessments and preparations (ie cover trials, geochemical void modelling, geochemical waste dump modelling). The success of this holistic strategy is evident by the awareness of personnel within the business, thorough understanding of the geochemistry and by undertaking proactive management of black shale during mining. The strategy and management plans adopted by Rio Tinto Iron Ore have activities that other mine sites with potentially acid forming material may like to consider implementing.

Jan 1, 2009

The Que River and Hellyer polymetallic massive sulphide ore bodies are located 3 kilometres apart in the Cambrian Mount Read volcanics of Western Tasmania. Both deposits are classic examples of the Kuroko volcanogenic style. Base and precious metal rich hydrothermal solutions rose through a deep fracture system and vented on the sea floor, causing sulphides to accumu- late in adjacent topographic lows. Together the preproduction geological resource is approximately 23 million tonnes at greater than 18% zinc plus lead, with economically significant silver and gold. Exploration by Aberfoyle in the Mount Read volcanics com- menced in 1970. Que River was discovered in 1973 following a comprehensive data review, a regional stream geochemical survey and a helicopter-borne electromagnetic survey. Production began in 1981, and the mine is currently producing 300,000 tonnes per year. The ore is sold to the Electrolytic Zinc Company of Aus- tralasia Ltd mill at Rosebery. Ten years of extensive geological mapping, soil geochemistry, and induced polarisation, combined with continual study of the Que River orebody and its host rocks, formed a strong frame- work for the discovery of the Hellyer deposit, which was found as a result of drilling .a subtle time domain electromagnetic anomaly in 1983. Hellyer is currently being mined at a rate of 250,000 tonnes per year, with the ore being concentrated at Aber- foyle's converted Cleveland tin mill. Treatment of 1 million tonnes per year will begin in early 1989 at a new mill located near the Hellyer site.

Jan 1, 1988

The C.S.A. copper lead zinc mine, located seven miles north of Cobar in Central Western New South Wales, is the largest known mineral occurrence in the Cobar Mining Field. Hosted by the steeply west dipping, west facing sediments of the Cobar Group, the generally discordant orebodies occur within a strike width of 600 ft and an overall strike length of 1200 ft. They comprise lenticular steeply north pitching and east dipping zones of sulphide mineralisation which range in composition from massive pyrite-sphalerite-pyrrhotite--galena to less massive pyrite- pyrrhotite-chalcopyrite varieties. The thinly bedded siltstones, shales and graywackes hosting the mineralisation appear to have derived many of their constituents from volcanic sourcesä They have been metamorphosed to the greenschist facies of regional metamorphism. At least two stages of deformation and folding have occurred. The first stage folded the rocks on a south pitching fold axis into their present configuration, and super- imposed a strong axial plane cleavage which subsequently guided the emplacement of the mineralisation. The second stage of deformation is considered to have controlled the zonal distrib- ution of the orebodies and the appropriate fold axis appears to coincide with the long axis of the orebodies.

Jan 1, 1969

By M Camarda, A Pirson, F Vasconcelos, J Mesquita

ArcelorMittal Prijedor is a goethitic iron ore mine located in the north-west of Bosnia and Herzegovina, which mainly supplies ArcelorMittal’s European subsidiaries. Annual production of the asset stands at the level of 1.5–2.1 million tons of iron ore product which is sent to ArcelorMittal Zenica steelmaking plant. Two types of products with approximately 50 per cent Fe are generated in Prijedor through a process composed by crushing, screening, and magnetic separation stages. Within this process one of the tailings produced is called ‘ultrafines’. The ‘ultrafines’ product corresponds to the desliming hydrocyclones overflow in Prijedor plant, which is classified in a size fraction below 25 μm and corresponds to about 5 per cent of feed. This material is richer in iron than the coarser size fractions of the ore but do not present a good performance in concentration processes. In this way, several studies have been carried out during the last years to find solutions to use the ‘ultrafines’ material without success. In this context, the possibility of dehydroxylate the goethite contained in the material transforming the mineral into hematite and thus increasing the iron grade of the final product was investigated. During the research, several dehydroxylation tests with different temperatures and time of exposure were performed. Using dihydroxylation process at temperatures higher than 800°C it was possible to produce a material with 43 per cent Fe from the original 39 per cent Fe ‘ultrafines’ sample. In addition, the dehydroxylation tests confirmed that goethite becomes completely transformed into hematite at 400°C (with an exposure time of 60 mins) and material is completely sintered at 1200°C. A simulation study based on dehydroxylation tests results showed that it would be possible to use a ‘ultrafines’ product with Fe grade higher than 45 per cent to produce a material with 50 per cent Fe through a complete dehydroxylation process.

Sep 18, 2023

By C Rothfuss, X Wang, S J. Herbert, K Prasad

The extraction of groundwater to produce gas from coal seam gas (CSG) reservoirs has highlighted the opportunity for beneficial uses of groundwater in Australia. This paper presents an assessment of alternate groundwater modelling approaches that can be used for assessment of one beneficial use option, that of injection. This assessment examines the outcome of the use of different simulation methods on predictions of hydrodynamic behaviour.In this paper, a simplified hydraulic concept of a multi-aquifer system within the hypothetical injection field was used to investigate the hydrodynamic behaviour of injection into the Precipice Sandstone. Comparisons were made through the analysis of a Theis 3D analytical solution with 2D and 3D numerical solutions. The paper discusses the different solution methods and the impact of these on predictions of pressure and flux. Differences in 2D and 3D solutions result in implications if planning injection as a beneficial use of water. For example, the 2D solution resulted in faster and higher injection pressure build-up when compared to the 3D solutions. The 2D modelling could result in either plans that require higher capital expenditure for a greater number of wells in order to spread the pressure effect and remain below the maximum injection pressure or a reduced injection rate. Meanwhile, the 3D modelling with sensitivity analysis could result in planning for lower capital expenditure for fewer wells required to spread the pressure effect and remain below the maximum injection pressure. CITATION:Wang, X, Herbert, S J,?Rothfuss, C and Prasad, K, 2013. Assessment of effectiveness of artificial recharge for coal seam gas water management based on numerical modelling, in Proceedings Water in Mining 2013 , pp 67-72 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 26, 2013

By J Nemcik, E Baafi, I Porter, G Spinks

Spray-on liners used in the mining industry for ground support and stabilisation applications are either cement based (æshotcreteÆ) or polymer based (æthin spray-on linersÆ). Some thin spray-on liners are a blend of both polymer and cement (eg Tekflex). A small number of thin spray-on liners (TSLs) have been trialled in Australia as potential replacements for steel mesh in roadways and other underground mining applications; however, they were found to cure slowly and the cured coatings became brittle after an extended time in place. The University of Wollongong in collaboration with the Australian coal mining industry has shown that a viable polymer-based alternative to steel mesh in underground roadway support applications can be developed to eliminate the use and handling of steel mesh. The work to date has: established the feasibility of developing polymeric alternatives to steel mesh in underground roadway support applications; identified the physical and material constraints to be endured by any new polymeric skin reinforcement system by measuring the mechanical properties of steel mesh; identified materials that can be spray applied; and demonstrated that polymer mechanical properties can be optimised to produce similar mechanical properties (elastic modulus, yield stress, elongation-at-break, etc) to steel mesh. The identified materials will: allow the face support cycle to be fully automated, or at least remotely operated and installed; remove personnel from the immediate face area; and substantially improve underground roadway development rates.

Jan 1, 2008

By W Zeng, D Walker, D Cai, E Baafi

"The efficiency of the truck-shovel haulage system is significantly influenced by the truck fleet size. A discrete event simulation model with 3D animation has been developed to estimate the productivity of a truck-shovel network system, shovel efficiency, truck cycle time, truck utilisation and the optimal fleet size. The simulation model considers the dynamic variability of traffic conditions and also the truck as an individual entity. The resulting truck cycle time was found to be realistic and thus providing a better tool for strategic mine planning.Citation:Zeng, W, Baafi, E, Walker, D and Cai, D, 2016. A 3D Discrete Event Simulation Model of a Truck-shovel Network System, in Proceedings Ninth AusIMM Open Pit Operators' Conference 2016, pp 265–273 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Nov 15, 2016

By N Maistry, C Carelse, A Singh

Banded Iron Formations or more commonly known as BIF are sedimentary rock formations with alternating silica-rich layers and iron-rich layers that are mainly composed of iron oxides (hematite and magnetite), iron-rich carbonates, and/or iron-rich silicates. Considering the depletion of highgrade iron ore reserves in South Africa, there is a need to maximise resource utilisation through the exploitation of low-grade/uneconomic resources particularly BIF material, which makes up more than 65 per cent of current reserves. Previous test work conducted by alternative BIF sources globally indicates the need for fines processing in order to produce a concentrate. South African BIF however is amenable to coarse and fines processing producing an on-grade product or blended feedstock. C-Type material within South Africa’s Northern Cape Province grading at approximately 33 per cent Fe was supplied for research purposes. Top size optimisation via gravity Heavy Liquid Separation (HLS) tests was conducted. The laboratory results being perfect separation (Ep=0) were modelled to predict pilot performance, the results of which were tested on a pilot scale for the finest size fraction (-1 mm). It was observed that a top size of -2 mm provided optimum results in terms of upgrade and recovery, with crushing finer not necessarily producing superior results. At a target grade of 60 per cent Fe, recoveries of 65.6 per cent were achieved on the laboratory scale, whilst recoveries of approximately 58 per cent were achieved on the pilot scale. Targeting higher upgrades of 63 per cent would inevitably result in lower recoveries of 57.2 per cent on a laboratory scale and approximately 54 per cent on a pilot scale. This is in line with grades and recoveries achieved globally for BIF material albeit at finer grind sizes.

Sep 18, 2023

The theme of my address to your Institute, indeed its name, is "The Mineral Industry - What Next?" Knowing that I was required to make four appearances, and not wanting to be too repetitious, I wrote a rather long speech of which I will deliver various sections at different places, with a common introduction. Specific areas I have addressed are "Exploration", "New sources of minerals and energy", and "Mining and metallurgy of the future".

Jan 1, 1984

By S Q. Zhao, J H. Wei

"An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation. The Xitieshan lead-zinc deposit is located in the north margin of the Qaidam Basin, Qinghai Province, China. It is one of the largest massive sulfide deposits in China and is supposed to be of the sedimentation-exhalation (SEDEX) type. Based on the main ore mineral and sulfur isotopic compositions in sulfides found in the wall rock, the S of the deposit is considered to originate from the mantle, but the fluid potentially mixed with sea water during the hydrothermal circulation exchange. The study of lead isotopes shows that the metallogenic material is characterised by the mixture of orogenic and upper crust sources. The lead isotopic signature of the wall rock is similar to that of the ore, which shows synsedimentary characteristics. According to the composition of the rubidium and strontium isotopic signature, the value of 87Sr/86Sr is lower than the average value of that in the crustal rock, which is larger than that of the mantle. Hence, the metallogenic materials of this deposit mainly originate from the crust, which is related to materials of volcanic rocks activation and migration of the deep hot circulating water. The process of the metallogenic fluid circulation shows continuous interaction with crustal material and lead to continuous enrichment of the ore forming fluids. From the study of the fluid inclusion microthermometry of the ore and the associated minerals combined with the C, H-O, Si isotopes, it is believed that the metallogenic fluid is mainly coming from the mantle or the deep magma chambers. The rising deep fluid then mixes with the sea water. The carbon dioxide escaping and mixing with sea water during the hydrothermal exhalation process leads to the rapid precipitation of the hydrothermal fluid to deposit metal. That is proposed as the principal formation mechanism of the Xitieshan deposit. Further studies are proposed, including obtaining geochronology data from this deposit.CITATION:Zhao, Z X, Wei, J H, Liang, S N and Zhao, S Q, 2015. Advances in research on metallogenic mechanisms for the Xitieshan sedimentation-exhalation lead-zinc deposit, Qinghai Province, China, in Proceedings PACRIM 2015 Congress, pp 487–494 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 18, 2015

By Hayward SB

The Maragorik prospect is an example of high sulphidation, Cu/Au mineralisation occurring at a high level in the hydrothermal system. As extensive ash deposits blanket the region, controlled-source audio magneto-tellurics (CSAMT), in conjunct-ion with bulldozer trenching, have been used to delineate subsurface geology. Fluid upflow has occurred along EW structures dilated by rotation on the bounding major NW lineaments. Rising hydrothermal fluids have exploited permeable horizons in contact with the upflow structures. This lithological control is evident as ledges of silicification and peripheral clay alteration, at high levels in the system. As is typical of high sulphidation systems, a two phase fluid consists of an initial rapidly moving vapour-dominated phase, followed by a liquid-dominated phase. Much of the zoned and overprinted silica to clay alteration is developed from the vapour-dominated fluid. Mineral deposition occurs as a result of brecciation of the competent silic-ification by liquid phase fluids. Such mineralisation is of restricted volume in ledges proximal to the feeder structures.The style of alteration and mineralisation are indicative of a very low temperature and hence a high level system. Thus, although high sulphid-ation systems are inferred to develop from porphyry-related magmatic fluids, such a source at Maragorik is interpreted to be very deeply buried.

Jan 1, 1994

By Reeves I. And Farquhar J, Pearce S

The irregular shape of the Rosebery orebody, coupled with the inconsistencies in grade over short strike lengths, has meant stoping blocks have had to be small to combat dilution and stability problems. In the past, each lens was divided into regular block sizes and developed up to five years before production commenced. There were two major drawbacks to this practice; firstly, existing development deteriorated over time therefore requiring rehabilitation prior to production. Secondly, the pre-determined blocks could not be easily changed to incorporate changes in mining technology or economic circumstances. Bearing these problems in mind, it was evident that any new lens development had to be designed to allow maximum flexibility. The lens being currently developed is J lens. It represents approximately 50 per cent of the current reserves tonnes, and 65 per cent of the zinc metal. Its importance to the mine's future cannot be over emphasised. At its core the lens is up to 25 m thick at grades of over 30 per cent zinc. The practice of dividing the orebody into levels and sublevels, with consequent crowns was no longer acceptable because of restrictions in stope design and potential loss of ore. To assist in the development planning of J lens, a geostatistical block model was applied in long section to graphically represent the lens. Areas of high zinc concentration, as well as zones of uneconomic material were identified by using the model. This has meant that the development could he targeted, enabling stope delineation to occur in the lens without significant ore loss. Because of limited development resources, and the need to bring J lens on-line in the near future, the development strategy has had to focus on 'just-in-time' principles, rather than accessing the whole lens from bottom, and progressing upwards. Tight development schedules have required individual stoping block to be developed on such factors as grade and available tonnes rather than as a vertical sequence.

Jan 1, 1993

By Barnett DW

Financial risk analysis provides the tools to examine the uncertainty of capital decisions in new mining ventures. This paper explores the methodology by which financial risks can be studied and quantified. The most commonly used risk evaluation methods, such as sensitivity analysis and discount rate adjustment, are presented as an introduction to a more comprehensive discussion of stochastic methods of discounted cash flow analysis using Monte Carlo sampling. The discussion is illustrated with examples of a stochastic discounted cash flow. The advantages of Monte Carlo sampling in risk analysis are discussed together with its problems, particularly those originating from the correlation amongst the variables that determine the economic output of a mining venture, and the difficulties created by insufficient data, imperfect knowledge and complexity. The paper also surveys the most commonly used software used in risk analysis.

Jan 1, 1994

By Tilley H. L

The 90 m deep Yallourn Open Cut brown coal mine in the Latrobe Valley, Victoria is developing into an area close to a reverse fault. A major batter stabilisation program, matched to ongoing operations, has com- menced to maximise coal recovery where the fault is within 100 m of the Open Cut. The various mine development options considered during the planning stages are outlined. These options were formulated in a back- ground of geotechnical constraints and the need to maintain continuous and reliable coal supply at a time when a new coal field would be developed. The geotechnical investigations and analysis procedures under- taken to determine stability of the batters during their excavation are presented. The geotechnical constraints on the mine design and opera- tions required to ensure safe working conditions are detailed. Current operational and batter stability conditions are considered satisfactory.

Jan 1, 1989