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Case Study: Dragline Swing to Dump Automation By Peter Corke, CSIRO Manufacturing Technology/CRC for Mining Technology and Equipment (CMTE) Peter Corke presented a case study of a project to automate the dragline swing to dump operation. The project is funded by ACARP, BHP Coal, Pacific Coal and the CMTE and is being carried out on a dragline at Pacific Coal's Meandu mine near Brisbane. Corke began by highlighting that the minerals industry makes extensive use of large, mechanised machines. However, unlike other industries, mining has not adopted automation and most machines are controlled by human operators on board the machine itself. Choosing an automation target The dragline automation was chosen because: ò draglines are one of the biggest capital assets in a mine; ò performance between operators vary significantly, so improved capital utilisation is possible; ò the dragline is often the bottleneck in production; ò a large part of the operation cycle is spent swinging from dig to dump; and ò it is technically feasible. There has been a history of drag line automation projects, none with great success.

Jan 1, 1997

The scale and seriousness of AustraliaÆs social and environmental problems are no longer in doubt. We are consuming the opportunities of future Australian generations by our lifestyle choices. And at the global level, human activities are altering the very systems on which our species depends. Doing nothing about such problems as climate change is not an option. It is possible to move to a sustainable future but it will require fundamental changes to our values and national social institutions. We must recognise that we share a common future with the entire human family and the other species with which we share the planet. It is not just our humanitarian duty to improve the lot of the poorest people of the world. It is also enlightened self-interest because a world of increasing inequality will be a world of increasingly destructive tension.

Jan 1, 2004

By Parrington PJ, Bailey A

Serious exploration for carbonate-hosted lead/zinc deposits in the Pillara district commenced in 1971 when Trend Exploration acquired exploration tenements covering stream sediment anomalies in the Limestone Billy Hills area. Shell Minerals managed the project from 1974 to 1976, and BHP Minerals Limited assumed management during 1976. Carbonate-hosted 'Mississippi-Valley- type' Pb-Zn deposits most commonly occur in Palaeozoic shallow marine carbonate complexes. At Pillara upper Devonian (Givetian/Frasnian) reef complexes are preserved on the flanks of Precambrian basement 'highs'. Within platform and atoll facies limestones sphalerite-galena- marcasite-calcite mineralisation occurs as disseminations, veins and breccia matrix, mostly associated with fractures and fault zones. Early exploration concentrated on detailed surface geochemistry and IP geophysical surveys, with geological mapping and shallow target percussion and diamond drilling. Results were discouraging and did not indicate potential for a shallow base metal resource. During 1976-77 BHP adopted a grid diamond drilling exploration technique and commenced testing an area of approximately 50 sq. km, initially using an 800 m square grid. In 1978 high grade mineralisation was intersected in an area subsequently named Blendevale. This was in the seventh diamond drill hole in the 800 m grid drilling programme, and to date more than 400 holes have been cored in the Pillara area. Detailed drilling at Blendevale has defined a number of mineralised breccia zones within an area of 2.4 km x 0.5 km, at depths of 100 m to 600 m below surface. The breccia bodies are associated with a series of north-south trending normal fault zones, forming a graben structure. The mineralisation occurs as breccia matrix surrounding unaltered limestone clasts, as veins filling steep fracture zones, and as

Jan 1, 1986

Individual specimens of sphalerite from the Broken Hill lode vary considerably in manganese and iron contents, even within the same orebody, so that study of the overall variation of manganese and iron content of the sphalerite calls for the analysis of a large number of specimens. This difficulty has been overcome by analysing a series of recleaned zinc concentrate products, prepared from stope samples and their equivalents, from most of the developed sections of the lode. The analyses reveal that during the formation of the sphalerite the concentrations of iron, manganese and zinc in the mineralizing solutions varied independently of one another from place to place in the forming orebodies, and also in time.The overall pattern of variation of the iron and manganese contents of the sphalerite in the several orebodies of the lode bears a general resemblance to the overall pattern of distribution shown by several other elements, notably, cadmium, lead, bismuth and arsenic. The iron content of the sphalerite indicates that it was formed at a temperature of 6000 C. or higher, but the variation in its iron and manganese contents demonstrates that Kullerud's method for determining the temperature of formation of sphalerite from its iron content must be used with caution if only single specimens of sphalerite are available.INTRODUCTIONThe four chemical analyses available of specimens of practically pure sphalerite from the Broken Hill lode (Table 1) reveal that the manganese content of the sphalerite varies considerably, and that there is a significant variation in its iron content. The variations revealed between individual specimens within the same orebody in the same mine suggest that specimen material is unsatisfactory as a basis for studying the overall manganese and iron contents of Broken Hill sphalerite, unless a great number of specimensis analysed.

Jan 1, 1956

By H M. Ahmed, W S. Dunbar

Construction of cave mining systems requires significant capital expenditure and long-term commitment of human, equipment and material resources before production commences. Risks and uncertainties of these large-scale mining projects are significantly higher than for small-scale projects. This is due to the complexity and interactions of the construction schedule components and the large scale and uniqueness of such projects. One way to successfully manage construction uncertainties that would lead to schedule delays is to include a reasonable cost contingency in the budget estimation. A real options approach based on the least-squares Monte Carlo (LSM) method is used to estimate cost contingency associated with schedule uncertainty in mass mining projects. Cost contingency is estimated as the cost of potential project crashing (acceleration) decisions, which pays for not extending the schedule. While such a significant undertaking is expected to be subject to some delays, these can have an enormous impact on the economic value of such projects. The value of the crashing option was explicitly formalised into the process of valuation, as it is assumed to be a single option being considered in the valuation at every decision point prior to the construction completion date. As a part of the proposed method, a stochastic function for the percentage of remaining scope of work for the remaining duration of the entire project was integrated into a framework of numerical simulations. This ensured that this function can implicitly account for sources of schedule uncertainties for projects represented by multiple and overlapping work packages. The LSM method was applied to a real case scenario in an operating block cave mine, with modified scale and features. The results yielded by the LSM method indicated that significant changes in capital budget allocation stem from variation in a contractor’s risk perception and confidence level of estimated delays.CITATION:Ahmed, H M and Dunbar, W S, 2016. Budget estimation and contingency allocation of block cave construction using least-squares Monte Carlo real options, in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016), pp 801–808 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016

By Mitchell G. W, Purvis A. H

The Lady Loretta silver-lead-zinc deposit lies north of Mount Isa in folded and faulted Proterozoic carbonate sediments. The deposit was discovered in the late 1960's as a result of a soil geochemical survey. Subsequent surface drilling outlined mineralisation folded into a synclinal structure extending to a depth of 460 m and containing exceptionally high grades within the keel of the syncline. Pancontinental Mining Limited and Outokumpu Oy of Finland acquired the property in 1985.

Jan 1, 1988

By F Clark, B Catto

The Mako domain comprises the Mako lodes at Sunrise Dam Gold Mine, Western Australia. This domain was initially bulk or æbucketÆ domained for the open pit resource in 2000, due to complexity in defining the lodes as a result of low drill density. Negative ore tonnage and positive grade and ounce reconciliations were experienced during mining of the domain in the mega-pit, though only small volumes of the domain were mined. Significant amounts of exploration and underground grade control drilling has been completed since the initial bulk domain interpretation and greater geological understanding of the mineralisation controls and geology of the lodes now exists. Mako provides approximately 50 per cent of the ore tonnes and ounces for the North Wall Cut-back, the latest open pit phase of mining at Sunrise Dam. The importance of Mako to mill supply and life-of-mine planning, as well as past reconciliation performance necessitated a reinterpretation of the domain to increase confidence for mining. Historic exploration drilling, underground grade control drilling and detailed pit-wall mapping were used to build mineralised subdomains within the confines of the original domain. These reflect more closely the spatial extents and geological controls on the mineralisation. A new resource model using the multiple indicator kriging (MIK) technique was generated using the new domains. It resulted in a decrease in tonnes and ounces but increase in grade for the sum total of the new domains compared to the old æbucketÆ domain. This is attributed to the increased selectivity and structural constraints imposed by the new domains. A retrospective comparison of the Mako grade control from the mega-pit versus the new resource model was conducted, which æreconciledÆ 103 per cent tonnes, 106 per cent grade and 110 per cent ounces. This has provided confidence that the new model is a better estimate of the lodes. Qualitatively, the new model is a better representation of the geology and extent of the mineralised structures with significant areas of change identifiable. Grade-tonnage plots comparing the 2006 and 2008 models show that most tonnes have been shed from the low-grade û subeconomic grade cut-offs. This is mostly attributable to the volume reduction of æoreÆ in the 2008 model compared to the 2006 model, where the true mineralised zones are captured by the new domains. The reinterpretation and remodelling of Mako is an example of an evolved domain model and shows that mineralised zones need to be differentiated adhering to the geology and geological controls on mineralisation, which are understood largely due to increased drilling density coupled with mapping.

Jan 1, 2009

Through the stress synthesis of many examples of macrostructure in the middle of China, it can be concluded that in the middle of Chinesetectonics there are two compression-torsion-forces, one of which ( from NW to SE ) came from the northwest side of Aerjinshan abyssal and giant fault("F1A", see Fig.7,8,9 ); the other (from S to N ) came from the south side of the north piedmontal fault of Kunlunshan-the south piedmontal fault of Qinlingshan ("F2K-F2Q", see Fig-7,829 ).Owing to the two compression torsion forces a new special type of structure named rotation-apart structure occurred from Chaidamu basin to Hebai, Henan, Anhui plain,from Caledonian movement, Hercynian movement,Yenshan movement to Himalayan movement, step by step In the north of Qilianshan during the late Caledonian movement: during the Hercynian movement it extended into a vast area including the Chaidamu basin and Eerduosi basin; during the Yenshan movement it spread over the whole area of Helanshan,Eerduosi basin and Hebai , Henan, Anhui plain. In the period of Himalayan movement all these structures revived .The rotation-apart structure controlled the distribution of all mineral deposits and also were the mineralizing structures.The relation between these rotation-apart structure and earthquakes is very close.

Jan 1, 1990

The continuous casting of zinc alloys has been of fundamental importance for many years in the production of a number of products, including sheet for architectural applications, battery cans for dry cells and wire for metallising. The intrinsic benefits of continuous casting, including efficiency and high tonnage capability, uniformity of metallurgical structure and properties, and absence of voids and other defects, have contributed to the success of these products. Less well known, but of growing importance, is the more recent application of continuous casting technology to the production of zinc alloy bar stock products, including bearing stock, machining bar stock, forging stock and cathodic protection anodes. A wide range of zinc alloys are now continuously cast in a variety of cross sectional shapes and sizes to suit the diverse characteristics of these products. Of particular significance are the introduction of hollow zinc-aluminum bearing stock, and the availability of zinc alloy machining bar stock for hydraulic applications and for producing prototypes of zinc alloy pressure die castings. In addition to the traditional benefits, continuous casting provides special properties which are important in the application of these bar stock products. The list of successful applications of continuously cast zinc alloy bar stock is growing rapidly, and the market potential for resultant new zinc applications appears to be significant.

Jan 1, 1993

By Aziz NI, Guo H

Most of the existing models of the mechanisms of drilling and cutting processes are oversimplified in both stress state and failure criterion. On the other hand numerical modelling techniques are a more versatile method with great potential for development. In reviewing drillability and predicting performance of excavation machines the empirical tests, which simulate the physical breakage action in excavating processes are seen to be the best in terms of penetration rate predictability. Future methods of determination of drillability should concern the breakage characteristics and rock abrasivity involved in the two basic types of attack, i.e., percussive and rotary drilling.

Jan 1, 1988

By L Jackson, A Parbhakar-Fox, N Fox

"Characterisation of sulfide minerals (eg pyrite, sphalerite) in historic tailings can assist in determining whether there are economic benefits of reprocessing such materials using modern metallurgical practices. In addition, there are associated environmental advantages if the historic tailings are actively generating acid and metalliferous drainage (AMD). At the Old Tailings Dam (OTD), Savage River, Western Tasmania, 38 Mt of pyritic tailings were deposited from 1967 to 1982; consequently it has been recognised as an AMD source. Long-term management options considered for this site have included the establishment of either a water, hard-engineered or vegetation cover. However, due to geotechnical challenges posed and the lack of success demonstrated by previous pilot studies, these strategies have not been implemented. Instead, resolving the pyrite chemistry can allow for a first-pass assessment of whether reprocessing these tailings is a feasible option as part of a long-term management strategy for this legacy site.Tailings samples (n = 144) were collected across the OTD from up to 2 m depth from five facies (A–E), and four zones (1 to 4; defined by hydrological regime and grain size). These materials were subjected to acid-base accounting (ABA) and mineralogical evaluations to determine their geoenvironmental characteristics. Following this, 26 samples were selected for in-depth laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) investigations to evaluate pyrite chemistry across different tailings facies. The results revealed enrichment of Co and Ni in these materials. Specifically, Co content was up to 3.0 wt per cent, particularly within facies C to E, and Zones 3 and 4. Cobalt is recognised as a critical metal, therefore, reprocessing should be considered as a future rehabilitation option for the OTD, pending resource definition using established codes and practices.CITATION:Parbhakar-Fox, A, Fox, N and Jackson, L, 2016. Geometallurgical Evaluations of Mine Waste – an Example from the Old Tailings Dam, Savage River, Tasmania, in Proceedings The Third AusIMM International Geometallurgy Conference (GeoMet) 2016, pp 193–204 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Jun 15, 2016

After a snap-shot survey of water quality of streams draining various coal measures carried out in 2000 - 2001, West Coast Regional Council expanded its monitoring programme to better establish the condition of streams draining coal mining areas and to characterise the variability of water quality with respect to stream flow. Samples were collected for water quality indicators such as pH, sulphate, turbidity, conductivity, temperature and dissolved oxygen as well as macro-invertebrates, fish and assessments of stream habitat. Water quality sampling was carried out at 27 sites on 21 streams located from Page Stream near Seddonville in the north, to Seven Mile Creek near Dunollie in the South, and to Garvey Creek east of Reefton. There was relatively low variability of pH, conductivity and sulphate concentrations at most of the sites sampled. Conductivity and sulphate concentrations reduced with increasing flow and pH generally increased. Significant effects on macro-invertebrate and fish populations were identified at several of the sites where water quality sampling was undertaken. Of the water quality parameters tested, macro-invertebrates were mostly affected by pH. Although not sampled directly (conductivity was used as a surrogate) heavy metal concentration may explain some of the variation in macro-invertebrate communities. Three creeks affected by mine drainage were sampled for fish and no fish were present. Fish appear to be more sensitive to acid rock drainage that invertebrates. Using data from this survey and other studies conducted in the region, the total length of stream that is actually or highly likely to be adversely affected by acid rock drainage was estimated at 125 km. This figure is useful as a gauge as to the magnitude of the issue in this region and for setting of priorities for remediation. However, as it is only an estimate based on limited sampling sites, it should be used with caution.

Jan 1, 2003

By M Simpson

Greywackes of the greater Auckland Region (Brynderwyn Hills to Hamilton), when considered on a regional scale, have characteristic ranges of physical, mineralogical and other properties. Some properties (eg density, porosity, crushing resistance, clay index) generally cluster and correlate with the basement greywacke facies, regions and terranes recognised by geologists, and their diagenetic/metamorphic level. Other local factors, particularly variations in mineralogical composition, nature of matrix cement, grain size, and degree of weathering may produce aberrant properties. Some of these local variations, when extreme, have the potential to affect the aggregateÆs performance in roading or the concrete industries.   Smectite and the zeolite laumontite are the major deleterious minerals occurring in fresh greywacke rocks of the Auckland region, although weathered rocks may contain halloysite, an expanding member of the kaolin clay mineral group. These minerals, when found in abnormally high levels in greywackes cause expansion effects in the aggregate. Currently there are inconsistencies in the detailed correlation of shrinkage, clay index, clay mineral content and intrinsic expansion data that need further research to resolve them.  

Jan 1, 2007

By Firth B. A

The classification performance of a Dutch State Mines (DSM) Rapped Sieve Bend has been investigated in a series of experiments. Coal slurries of a nominal 0.5 mm size were classified in the separation range of 0.10 to 0.14 mm at pulp densities from 6 to 21 per cent by mass of solids, and flow rates of 110 to 1375 litre min-1.The results obtained showed that the partition curve and water split io oversize was dependent on the solids flow rather than slurry flow rate or pulp density. For most of the operating conditions considered an accurate classification of the fine coal was obtained. The undersize efficiency was susceptible to solids flow rate, and was less than 70 per cent for solids flow rates greater than 16.7 tonne hour-1 metre-1 width of screen.

Jan 1, 1983

By A Madera, R Watt

The Tampakan deposit is a strongly telescoped high-sulphidation-epithermal/ porphyry deposit pair which is hosted by a sequence of probable Pliocene age subaerial andesite flows. These host units lie on the western flank of a deeply dissected andesitic stratovolcano within the northernmost portion of the Sangihe Arc in southern Mindanao. The deposit was discovered by WMC geologists in 1992 and is currently undergoing resource evaluation. Preliminary resource estimations indicate a total inferred metal content of 12 million tonnes of copper metal and 16 million ounces of gold. Using a 0.2 per cent Cu cut-off grade, the deposit has a current mineral resource of approximately 2.5 billion tonnes with an estimated grade of 0.48 per cent copper. At a higher cut-off grade of 0.5 per cent Cu, the mineral resource is approximately 900 million tonnes with an estimated grade of 0.75 per cent copper. Mineralisation is open both to the west and at depth. The Tampakan district is centrally located with respect to a 100 km wide zone of left-lateral strike-slip deformation represented by the trans-Mindanao Cotabato Fault Zone. The district is transected by several WNW-striking wrench faults which represent strands of the regional Cotabato Fault Zone. High-sulphidation epithermal mineralisation within the Tampakan deposit is strongly controlled by NNE-trending faults which lie along a dilational orientation within the Pliocene stress field associated with the Cotabato strike-slip fault zone. The mineralisation is broadly hosted by a gently-dipping, tabular zone of partial to massive silicification which displays multi-phase brecciation, acid-leaching, related vuggy porosity and which is developed within a district-scale advanced-argillic and argillic lithocap exceeding 90 km 2 in area. High-sulphidation epithermal mineralisation is associated with a silica-pyrophyllite-dickite-alunite-diaspore¦sericite alteration assemblage which is transitional downward to sericite-chlorite alteration and relict potassic biotite-chlorite-magnetite-anhydrite alteration associated with pervasively developed but weakly mineralised porphyry quartz stockwork veins. The high-sulphidation mineralisation is dominated by disseminated, vein and vug-filling enargite-bornite-digenite-chalcocite-covellite ¦ molybdenite which has overprinted an earlier phase of porphyry copper stockwork veins associated with high-level porphyritic hornblende diorite stocks. The distribution of high-sulphidation alteration and mineralisation reflects strong stratigraphic and structural controls. The high-sulphidation mineralisation covers a surface area of approximately 1.6 km by 2.0 km and forms a tabular, flat-lying to gently-dipping body between 200 and 500 metres thick. It is intersected at RL-1200 m ASL (at surface) in the northern portion of the deposit and extends down to RL-600 m ASL at the southern end. The deposit has been diamond-drill tested to a depth of 400 - 500 metres where low-grade chalcopyrite-bornite-pyrite mineralisation is hosted by pervasive quartz stockwork veins. This deep-level mineralisation represents the outer portion of a porphyry Cu system hosted by both andesite flows and the uppermost portions of high-level hornblende diorite stocks. Deep drilling to test for higher tenor porphyry Cu mineralisation is planned.

Jan 1, 1999

By Doyle R

Underground operations commenced at Tower Colliery in late 1978 and the early prevailing mining conditions in the worked seam were considered poor as a result of high stress and geological disturbances. This suggested that outbursting activity may be a possibility. The colliery has since recorded a total of 13 individual outburst incidents, all of which have been associated with the same dyke and strike-slip fault zone. This paper depicts the geological conditions and presents the results of investigations undertaken at the time of these outbursts.

Jan 1, 1986

By Sandenbergh RF

The debate on the mechanism of adsorption of gold and silver di-cyanide onto activated carbon could be divided into two schools of thought. On the one hand, it has been proposed that the combined effects of electrostatic and chemical interaction between the activated carbon surface and adsorbing gold di-cyanide anion results in the adsorption of the latter. On the other hand the `ion-pair' adsorption reaction mechanism has been vigorously advocated as the dominant mechanism responsible for the adsorption of gold di-cyanide onto activated carbon. It is maintained that gold is adsorbed onto the carbon surface as the neutral ion-pair [M"+][Au(CN)z ]". Adsorption is viewed as the result of mainly the chemical interaction while electrostatic interactions are neglected. The validity of the `ion-pair' adsorption mechanism may be challenged on a number of counts. However, the alternative mechanism (based on aqueous surface chemistry principles) has not gained general acceptance yet, because it has not been applied widely enough to explain the different adsorption phenomena associated with gold di-cyanide on activated carbon. In the present study the case in favour of an adsorption mechanism based on general aqueous surface chemistry principles is presented. A model framework is developed for the adsorption reaction mechanism of gold di-cyanide onto activated carbon which incorporates the effects of chemical and electrostatic interactions between the dissolved species, the aqueous solution and the carbon surface. This model is then employed to explain a wide variety of reported adsorption phenomena for gold di-cyanide on activated carbon, such as the effects of pH, the adsorption of different metal cyano complexes, ionic strength, and type and concentration of cations in solution. In addition the effects of cyanide and dissolved oxygen concentration were investigated. No ready explanation, in terms of aqueous surface chemistry principles, is yet available for the switch in adsorption behaviour that agrees with ion exchange to ion-pair adsorption with increasing ionic strength.

Jan 1, 1997

By Groves J

The sizing and classification circuits at the Mt. Newman Beneficiation Plant have performed satisfactorily. Investigations have been aimed at solving minor problems and achieving small' improvements. Emphasis has been placed on cost reduction rather than metallurgical performance. It has been found that some circuits will give better performance with the sieve bends removed. 1.0 BACKGROUND Mt. Newman. Mining operates a major iron ore mine in the Pilbara region of Western Australia. Rainfall is sparse (average 250 mm/year). Current mining is all above the water table. What rain there is tends to run off quickly instead of soaking in. The total operation produces about 30 Mt/ year of saleable product. Most of this product comes from high grade crushing plants where ore from the quarries is simply crushed and conveyed to product stockpiles. About 3 Mt/ year comes from the Beneficiation Plant.

Jan 1, 1984

Silver-lead mineralization at Indooroopilly, Queensland, extends upwards from Upper Triassic rhyolite which intrudes phyllite-containing Palaeozoic mineralization.Sulphides and magma were emplaced in a special structural site which underwent dilational fracturing while surrounding rocks were block-faulted and compressed. This site lies at tbe intersection of dykes, faults, and a lineament adjacent to a Middle Triassic granitic stock.Structural controls at Indooroopilly are attributed to the effects of piston faulting. Exploration for similarly controlled deposits should be directed towards structural intersections near stocks or batholiths which have intruded mineralized belts. Priority should be given to structural intersections which were sites of block-faulting and igneous activity under compressional tectonic conditions.Favourable sites lacking surface mineralization may contain ore at depth as piston faulting produces 'blind' ore deposits.

Jan 1, 1976

Tin mining has taken place in the New England region of New South Wales since 1872. Until fairly recent times there was little pro- vision made for environmental protection. Mining methods,which included ground sluicing and open cutting,had considerable environmental impact. Much of the topsoil was lost and there is little vegetation on the infertile and at times toxic, subsoil. Thus much of the lands disturbed by mining have not been stabilised and are eroding, causing extensive pollution of adjacent watercourses. There are more than 1500ha of abandoned tin mine sites in the New England, representing one of the worst rehabilitation problems in New South Wales and reflecting poorly on the mining industry as a whole. Recent tin mining operations incorporate progressive rehabilitation in their mining cycle. Topsoil is stockpiled and later respread. This topsoil contains a seed source, facilitating revegetation and thus stabilisation. The tin mining industry, under considerable cost pressures at present, is seeking a cost- effective revegetation technique. Most of the mines in the New England are situated in a forest environment. Trials have been conducted in the past using exotic pasture species with limited success due to the characteristics of the subsoil. Other revege- tation trials have used pine or eucalypt tree species. The cost of these techniques is a major disadvantage. Certain acacias species were observed colonising disturbed tin mining areas on very infertile subsoils. Acacias have a number of characteristics indicating a possible applic- ations in mine rehabilitation programmes.

Jan 1, 1987