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By M Wilson, D Whiteman, P Kuiper, S Talu, G Watt, A van As

Once the draw process has begun in a block cave, it is very difficult to identify which regions of the cave have successfully propagated, where the caved material is flowing from and where it is flowing to. The uncertainty around cave flow increases as the cave is drawn and can be further compounded by poor draw control practices. These uncertainties make it difficult to plan effective draw strategies to control dilution, as flow model predictions tend to gradually diverge from the actual state of the cave. There have been documented occasions where observed caving phenomena, such as muck pile surface rilling, could not be reproduced with the cave flow models of the time. The ultimate consequence of cave flow uncertainty is generally manifest as higher dilution and lower grades.In order to measure the real-time flow of caved material within an active block cave, CRC Mining and Elexon have developed, together with Rio Tinto, a cave flow monitoring system called Cave Tracker, which is being trialled at Argyle Diamond Mine (ADM) in Western Australia. The Cave Tracker system at ADM comprises electronic ‘beacons’ that have been installed down long HQ diameter drill holes located above the extraction level. As the cave-back propagates and the rock mass fragments, beacons are released into the muck pile and flow along with the caved material to the drawpoints below. At Argyle, the beacons are configured to emit a signal every three days. These signals are picked up by detectors installed on the extraction and undercut levels, allowing the positions of the beacons to be determined.By examining the real-time material flow in different regions of the cave, flow mechanisms can be better defined. Draw control strategies can then be actively tailored to manage the current state of the cave. Thus, previously undetectable indications of excessive rilling, rapid cave propagation, cave stall, air gaps and dilution entry can now be identified early and assessed continuously as the cave progresses. For the first time it is possible to amend draw strategies based on measurements from inside and outside of the fractured zones, allowing caves to be managed more effectively.CITATION:Whiteman, D, Talu, S, Wilson, M, Watt, G, Van As, A and Kuiper, P, 2016. Cave Tracker flow monitoring system installation at Argyle Diamond Mine, in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016), pp 479–488 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016

Sphalerites from Devonian cassiterite-sulphide deposits and Pb-Zn-Ag fissure veins have similar ranges of Cd contents, but the average Cd and Fe contents could indicate a small initial difference in availability of Cd between the Zeehan-Renison Bell district and the Mt. Bischoff-Waratah district. Sphalerites from banded Pb-Zn deposits (Rosebery and Hercules) are characterized by low Cd content which is a world-wide feature of such deposits in exIrusive rocks, and may indicaIe a genetic relationship between ore deposition and vulcanism.

Jan 1, 1968

ON mineral lease 38 of the Sulphide Corporation Limited, Broken Hill, a shaft was sunk in the early days Ior prospecting purposes and at the present time it is accessible as far as the 1000-ft. level where a connexion exists with the main workings of the Corporation's Central Mine, mineral lease 9. About the year 1895· a crosscut was driven east from this shaft at the 1330-ft. level cutting the Central Ore-body in mineral lease 9 and the shaft is supposed to extend a further depth of 25 ft; but no records of any of this work are in existence, the whole of the evidence being based on hearsay and memory:Fig. 1 shows the position of the Extended shaft in relation to the main workings. The shaft filled with water to the 1000-ft. level where it overflowed through the crosscut to the main shaft and was pumped to the surface, but when the South drive on the 1300-ft. level was pushed to the southern boundary, it was deemed advisable for safety, to tap the water at this level and so relieve the...

Jan 1, 1919

Environmental information is an essential part of successful mine design and approval. In order to be most effective in its application and availability, this information needs to be collected in programmes with defined objectives and deadlines. Applied Geology Associates have established a methodology to facilitate the structured collection of environmental data, which provides for the diverse needs of both engineering design and applications for statutory and non-statutory approvals. Principal aspects of this methodology are the scope, timing and management of the environmental studies within the overall project planning framework.

Jan 1, 1987

By A J. Eggers

With gold first discovered at Carrick in 1864, exploration and mining on the Carrick Goldfield in Central Otago, New Zealand, has now been ongoing for more than 130 years. Recorded historical hard rock production from up to 52 different mining claims from 1864 to about 1921 is 24,047 ounces (oz) of gold.   Since 1980 Amoco Minerals New Zealand Limited, CRA Exploration Pty. Limited, Amax Gold Mines New Zealand Limited and Summit Gold (New Zealand) Limited have conducted modem systematic exploration campaigns targeted at locating shear controlled gold bearing quartz lodes and stockwork deposits. More than NZ $1million has been spent by these companies on aerial photography, geological mapping, stream sediment surveys, soil and rock chip geochemistry as well as reverse circulation (RC) percussion and diamond drilling.   RC drilling by Summit Resources in 1997 has identified a 1,500 m long zone of low-grade gold mineralisation at Lower Carrick, with an average grade of 1.00 g/t Au over a 14 m average thickness. This gold mineralisation, hosted within a low angle shear zone, has analogies with the Hyde-Macraes Shear Zone in eastern Otago. Recent exploration and drilling at Carrick has revealed the potential to discover large (>0.5 million ounce (Moz)) low-grade bulk shear controlled quartz vein and stockwork gold deposits similar to those now being mined at Macraes.

Jan 1, 1997

Particle Size Measurement of TiO2 Nanoparticles in Non-Aqueous Solvent by Interactive Force Apparatus Under an Electric Field

Sep 13, 2010

By M Flis

The Razorback Iron Ore Project is a high tonnage, low-grade magnetite deposit that defines a new iron ore district in South Australia. Known since the 1960s, the deposit has come into its own as the iron hungry world demands not only larger tonnages, but higher grade and cleaner magnetite concentrate ores that counterbalance the increasingly dirty haematite ores that are coming into production.Razorback is hosted by the Neoproterozoic Braemar Iron Formation, a tillitic unit that is part of the Adelaidean Geosyncline sedimentary sequence. At Razorback, this formation forms the southern limb of the Pualco Syncline, dipping at 42° to the north and outcropping along a prominent ridge. The formation consists of a series of alternating bedded tillitic and interbedded magnetite units that represent cycles of glacial advances and retreats. Seven cycles, resulting in seven stratigraphic members, are recognised. Members B, D, and G are the thickest, at 30 - 70 m each, and are the target of current investigations. While the bedded magnetite has the highest iron content, typically 35 per cent Fe, the tillitic unit, at typically 26 per cent Fe, has similar iron content in the ground mass but is diluted by the inclusion of iron-poor granite and metasedimentary dropstones. The mineralisation forms a simple dipping tabular body with only minor faulting, folding and intrusives. Grades, thickness, dip, and outcropping geometry remain very consistent over kilometres of strike, presenting an excellent mining proposition.Razorback differentiates itself from other Australian magnetite projects in a number of important ways. It is not a banded iron formation (BIF); it will have low crushing and grinding costs; and it is located in an infrastructure-rich area close to open-access, high capacity rail, to a selection of ports and to gas, electricity, labour and engineering services. Royal Resources has announced an Inferred resource of 277 Mt @ 25.9 per cent Fe. The company is targeting a resource of 500 - 1000 Mt to support a 10 Mt per year concentrate production. Davis Tube Recovery work shows that the ore is capable of producing a concentrate of over 68 per cent Fe with very low deleterious elements. Metallurgical testing confi rms the ore is soft, and with near-zero initial stripping ratio the project will have a low opex. With access to existing critical infrastructure, capex will also be low, ensuring Razorback will be a highly competitive iron producer in this emergent mining district.

Jul 11, 2011

By T Christie

Tertiary volcanic rocks make up a significant proportion of the surficial cover rocks of New Zealand, especially in the Taupo Volcanic Zone. Industrial minerals that are associated with or derived from the volcanic rocks include: amorphous silica, allophane, bentonite, diatomite, ignimbrite building stone, illite clays, halloysite clay, obsidian, perlite, pumice, sulphur, titanomagnetite ironsand and zeolite. Of these: bentonite, ignimbrite building stone, perlite, pumice and titanomagnetite ironsand have been mined and processed for 20 to 30 years, but many of the others require further characterisation of the resource and/or development of markets.   We have compiled interim mineral deposit models for halloysite clays in rhyolite and for zeolites in altered vitric tuffs. These models include geological and mineralogical attributes, which are linked to the underlying volcanic and geothermal processes that have produced the minerals and their source volcanic rocks. Halloysite clay deposits at Matauri Bay (Northland) have formed from hydrothermal alteration and weathering of rhyolite. Clinoptilolite + mordenite zeolite deposits in the Ngakuru area (Rotorua district) have formed from hydrothermal alteration of volcanic glass in lacustrine sediments and ignimbrite. Further refinement and application of these models will result in a better understanding of the mineralogy, localisation and origin of the deposits, with consequent applications in exploration and resource assessments.

Jan 1, 2001

By S McKinley

"The White Mountain sediment-hosted gold deposit is located in north-eastern China. Mineralisation is associated with silica–hematite–altered polymict breccias that occur within dolomite at or near the contact with overlying sandstone. Economic gold grades are controlled by the distribution of the polymict breccias and can transition rapidly to low or zero grade over short distances. This results in sharp and highly irregular ore contacts on whose accuracy proper stope design and ore control is reliant at this blasthole underground mine.Short-term planning and ore control utilise a grade control model created from infill drilling and grade control sampling (ie face and wall sampling). Typically, the grade control model was maintained by time-consuming manual editing of earlier made contacts to incorporate any new data. This approach also was quite error-prone due to: the complexity of the breccia and ore grade contacts irregularly oriented and/or insufficiently dense drill holes inconsistent incorporation of grade control sampling. These errors resulted in unplanned dilution and ore loss due to inaccurate interpretation of the ore contacts.The primary advantage to implicit geological models over conventional, manually-built wireframe models is that they can be updated very quickly and frequently. In a mine setting, the power and efficiency of using an implicit model is greatest where the use of manual inputs or editing can be minimised. Recently a workflow was set-up for the mine geology team to create an implicitly-modelled ore shape for short-term planning needs by using all data, especially all grade control samples. The resultant 3D shapes provided metre-scale accuracy and consistently reconciled complex ore geometries much faster and to a higher degree of quality relative to the wireframe model. The mine stakeholders can now obtain an accurate ore model that will always be in sync with available data.CITATION:McKinley, S, 2017. Application of implicit geological modelling to improve the grade control process at White Mountain gold mine, Jilin Province, China, in Proceedings Tenth International Mining Geology Conference 2017, pp 385–392 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Sep 20, 2017

By Johnson I. R, Muir M. D

The Dugald River zinc-lead deposit is located 60 km northwest of Cloncurry. It was discovered prior to 1881, and since 1937, has been the subject of several drilling programmcs which have outlined a resource potential of 60 million tonnes grading 10 per cent zinc, 1 per cent lead, and 30 g/t silver.The deposit is a classical example of stratiform zinc lead mineralization in a black shale host. It occurs within a restricted clastic sedimentary basin within the Corella Formation of Carpentarian (Middle Proterozoic) age. Sabkha, lacustrine and fluvial sedimentary environments have been recognized within this basin. Each environment is characterized by suites of evaporite mineral pseudomorphs, after both shortite and gypsum, indicating that both alkaline and hypersaline environments prevailed at different times during basin evolution. The Dugald Slates which host the zinc-·lead mineralization are lacustrine in origin. Thin Mount Isa-type K-rich tuffite beds occur in the Dugald Slates and in the sabkha sequences.The basin as a whole appears not 10 have been marine, and 10 have had strong tectonic controls on its depositional history.The mineral deposit itself is conformable within the Dugald Slates and many primary sedimentary and soft-sediment deformation structures are preserved. It has a strike length of 2 km, average width of 10 m, and a westerly dip of 50-80 . Drilling suggests continuity to 1000 m vertical depth. The predominant sulphides are pyrrhotite, pyrite, sphalerite and galena in graphitic slate and quartz-carbonate ganguc. Anomalous concentrations of barium, manganese, cadmium, mercury and antimony are present in the ore.The deposit crops out over a distance of 2 km as a gossan ranging from 5-15 m in width. There is a striking vegetation anomaly over the gossanous outcrops. The gossan is enriched in lead, silver, antimony, barium, titaniulll, silica and iron, with respect to the primary mineralization. The depth of total oxidation reaches about 20 m.Cieochemical and geophysical test surveys over the deposit give pronounced anomalies.

Jan 1, 1982

This modern plant was installed with the object of treating all oxide ore and payable dump material by the cyanide process.The plant is located on a ridge on the eastern side of Linda Gully. The mill -site has a slope to the south of 1 in 4.The new plant is of steel and concrete construction and was specially designed to suit the climatic conditions which exist at Mount Morgan.THE COARSE CRUSHING PLANTThe ore received from the, mine is dumped into a 600-ton steel bin which is commanded by a 3 ft. 6 in. gauge railway,The mine ore is conveyed by steam locomotives in rakes of five self-dumping 7-ton railroad cars. The dump material is mostly loaded by bull-dozers and conveyed to the binsin large motor lorries. Located on the top of the bin is a heavy railroad grizzly having 12-in openings through which all ore must pass.The flow of ore from this steel bin is controlled by a No. 7D 3-speed Ross chain feeder. It should be mentioned here that, although the bottom of the steel bin is inclined at an angle of 45°, it has been found, owing to the clayey nature of the oxide ore, that the live capacity of the bin is only about 50% of the total capacity.

Jan 1, 1939

By J Bassan

The mining industry is faced with imperatives to improve worker safety and productivity, adapt to skills shortages, high worker turnover rates, and provide more effective maintenance to new and ever more complicated plant and equipment. While more effective use of data combined with advanced analytics offers opportunities for improvement, providing this information to the worker in the field, in real-time, has proven expensive, cumbersome and ineffective. New capabilities are now emerging which address some of the limitations experienced to date. Augmented reality (AR) provides a means to overlay interactive digital information on top of the physical world. Combining the latest visual display, mobile computing and ‘track and trace’ technologies, AR provides an experience similar to a heads-up display in a fighter jet through small, personnel devices, such as smart phones or wearable glasses. Applying AR would allow a mobile worker to ‘see’ all relevant information for a given task, in the context of their physical environment and at the time they require it. The technologies behind AR are rapidly maturing and becoming available at a price point that is viable for commercial applications. It is anticipated that AR will become ubiquitous at a consumer level within the next five years. The specific challenges faced by the mining industry make it an ideal early adopter of AR technologies. This paper examines a number of use-cases of how AR can be applied to the mining industry and the benefits that can be realised. The paper will identify areas of further work and viable opportunities for immediate adoption within the industry.

Nov 22, 2011

By P Allen, E Gleeson, D Boakye, R Chesher, S Konopa

"An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation. Not only do epithermal gold deposits provide many challenges in estimating mineral resources, the complexities of these deposits also provide technical challenges in assessing appropriate mining and processing strategies, as well as social and environmental planning and management. The characteristics of epithermal gold deposits include being highly variable with respect to geometry and gold grade distribution, the presence of other economic contributors, mineralogy, texture, rock strength, weathering and alteration overprint. These characteristics influence the economic value of mining projects in an interlinked manner. Consequently, successful exploitation of epithermal deposits requires a holistic approach, coupled with the effective integration of geological data to meet all aspects of mine development decision-making. This paper presents examples of the key technical challenges encountered in estimating and mining epithermal deposits. It also highlights why these issues need to be addressed from the viewpoint of geology, sampling, resource estimation, mine planning, mineral processing and social and environmental planning for the true value of the mining project to be realised.CITATION:Konopa, S, Chesher, R, Gleeson, E, Allen, P and Boakye, D, 2015. Challenges in maximising the value from epithermal gold deposits, in Proceedings PACRIM 2015 Congress, pp 127–132 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 18, 2015

By Creasey J. W, Huntington J. F

Faults cutting the Lithgow and Katoomba seams in some collieries of the Western Coalfield can be classified, on the basis of spatial pattern, into three principal groups: meridional swarms of closely spaced minor faults and associated joints, with throws of less than 0.5 m and with exceptional faults of up to 5 m; isolated interswarm strike-slip faults in the Lithgow seam and widely spaced strike-slip faults in swarms in the Katoomba seam; and low-angle normal faults associated with the Lidsdale-Lithgow seam split.Orientations of faults and coal cleats in the coalfield are presented on stereoplots and histograms, as a basis for an analysis of fault dynamics. The low-angle normal faults were found to have been formed only along the Lidsdale-Lithgow seam split, and before the high-angle faults. The origin of the high-angle normal faults in the meridional swarms is discussed and it is suggested that basementcover interactions must have occurred. This suggestion is supported by geophysical evidence. Low-amplitude monoclines in the coal seam, and the spacing of swarms 0.9 to 4.5 km apart, may be due to the underlying basement structure.It is clear that postextensional compressive deformation of swarms in the coalfield gave rise to shortening by minor thrust development, and probably also caused the synchronous strike-slip movement on pre-existing normal faults. There is evidence to show that isolated interswarm strike-slip faults in the Lithgow seam, and widely spaced strike-slip faults in the Katoomba seam, may have originated synchronously with such thrusts. The axis of maximum principal compression ('71) for the thrust event was inferred to be near horizontal and aligned approximately E-W. Recent rock mechanics measurements of the present day stress field indicate a similar stress configuration.

Jan 1, 1981

One of the most significant problems experienced in land reclamation work has been the tendency of earthmovers to over-compact the subsoils and topsoils. The need for extensive subsoil drainage, because of over-compaction, becomes a very expensive exercise and can be attributed to poor planning. The problem has been addressed both at the Waihi and Huntly open-cast mines through the use of low ground pressure machines in the placement of subsoils and contouring. The use of subsoilers working to contour to aerate the soils is essential to integrate both the sub and topsoils so that significant root growth and drainage is established. Waihi's rainfall (approximately 200 mm annually) and light soils create difficulties in preparing for the final seed bed. A noticeable factor in preparation of the growing medium was the reaction of the lime particularly in the subsoils (damp), from a lumpy, quite heavy texture to almost a seed-bed texture within a period of approximately 72 hours. Also the high incidence of stone and debris which was not apparent in the placement of subsoils meant the job became very labour intensive. This will be overcome with the importation of a machine from the USA. All of the rubber tyred tractors used on these projects are four wheel drive in the 6S-aOhp range which for weight distribution and the safety factors allows for good landscaping techniques. Good engineering practices should ensure that slopes of no more than 3:1 be designed, keeping in mind that the long term planning must allow for maintenance and stock management of restored land.  In the preparation of the final growing medium the equipment used included: Caterpillar 05 LPG and blade; three-four wheel drive rubber tyre tractors; Super flow subsoiler; hydraulic twin spinner manure spreader; discs û two types; harrows; MF Seeder; Cambridge Roller and Duncan Rotatiller.

Jan 1, 1991

By Davies S. G, Mackey L. C

The oxidation of iron and nickel sulphide concentrates, and the dominant sulphide minerals which comprise them, has been studied under ignition conditions using thermogravimetry (fG). The concentrates were derived from various minesites and they showed differing tendencies to ignite. Ignition temperatures ranged from 416 to 488°C and the extents of reaction, measured at 500°C, varied from 64 to 88 percent. The reactivity of the least reactivematerial was improved significantly by grinding. Particles <63/lm showed 85 percent oxidation compared with 55 - 65 percent for particles >63/lm.Examination of the individual sulphide minerals revealed that these materials also have significantly different degrees ofreactivity and are subject to particle size effects. For particles <45/lm, the ignition temperatures were as follows:ò pyrite and violarite 380 - 385°C; pentlandite 425 - 430°C; and pyrrhotite 470 - 475°;ò for particles >90 /lm, the ignition values were: pyrite 395 - 400°C;ò violarite 430 - 435°C; pyrrhotite 540 - 545°C; and pentlandite 560 - 565°C.Using the data on the individual minerals it was possible to rationalise the differing degrees of reactivity of the concentrates. The role of the most reactive constituent in initiating the ignition reaction has also been discussed.Finally, the results of this work were found to compare. favourably with the behaviour ofthe concentrates in industrial and pilot-scale flash smelters.

Jan 1, 1989

By O Salisbury

Ingress of air into the longwall goaf environment needs to be managed appropriately to reduce the risk of creating a spontaneous combustion event. The maingate goaf edge is an area of particular concern in this respect, as air often penetrates for some distance into the goaf along this region inbye of the longwall face. Since the flow rate in this part of the goaf is also quite low, an opportunity exists to disrupt the air pathway by implementing a barrier to the airflow. Previous attempts using plugs made from an assortment of materials have resulted in varying degrees of success. More recently, Narrabri Coal Operations (NCO) has introduced the use of a chemical foam that is mixed with nitrogen to produce a standing barrier with the consistency of shaving cream. The implementation of this practice has consistently proven to be very effective for reducing the oxygen concentration along the maingate goaf edge by systematically retreating the foaming unit with the longwall. This paper presents how the foam is applied in the underground goaf environment to prevent oxygen ingress and uses results from gas monitoring to confirm the foam effectiveness.

Oct 12, 2022

By Gupta R. C

Direct reduction of iron ore by solid reducing agents have been studied extensively and summarised by several authors (Otsuka and Kunii, 1969; Abraham and Ghosh, 1979; Frauhan, 1977; Rao, 1971; Kawasaki, Sanscainte and Walsh, 1962; Ghosh, 1970; Rao, 1979). While studying the reduction behaviour, it is generally agreed that the reduction occurs via gaseous intermediate, generated by carbon gasification reaction which involves mass transfer, heat transfer nucleation and growth, etc through a) reduction reaction occurring at solid reductant, and b) reduction reaction occurring at solid iron oxides, thus making the overall reduction process very complex in terms of clearly defining the reduction kinetics of the system. In addition to this, practical difficulties like correctness of reaction temperature, (Seaton, Foster and Velasco, 1983) difficulties in isothermal temperature studies of reduction, difficulties in monitoring the reduction process while using gaseous reductants and separation of reduction by volatile matter from overall reduction process make the reduction kinetics more complex (Misra).

Jan 1, 1999

Some 50 miles of tunnel have been driven in the Snowy Mountains Area since tunnelling commenced in 1951. Hates have improved progressively due to the know-how of American supervision and use of large matched equipment of modern design.The work has been carried out by contractors, working almost exclusively under schedule of rates contracts. The Authority has maintained active research into tunnelling problems, especially that of support, and this has resulted in considerable economies and improved rates of progress. The contractors also have sought economies both by management and equipment techniques. Ammonium nitrate came into favour as an explosive essentially because of its lower cost, and handling techniques have improved progressively. Rock conditions preclude use of the "Mole" type equipment in its present stage of development, but one contractor introduced the "sliding floor" and this could exert a great influence on future tunnelling methods.Examination of tunnels that have been in service for some time confirmed the quality of the work and endorsed the policy of continued research and development.GENEHALThe Snowy Mountains Scheme provides for the diversion of the Snowy and Eucumbene waters through two transmountain tunnels to the western river systems. These diversions, together with additional regulations provided for waters already flowing inland, will provide an average additional discharge of 1,818,000 ac it per year for irrigation.Furthermore, approximately 6,000 million kWh of electrical energy will be generated annually in power stations with a total installed capacity of some 3,000,000 kW (Fig. 1.).INVESTIGATIONThe aim of investigation work is firstly to collect sufficient information to allow the overall scheme to be planned and then to follow up with detailed information on eachproject. The correct balance for all aspects of this work is a matter for keen judgment, as the tunnels must be planned...

Jan 1, 1963

By Lyman G. J

Dense medium drum separator efficiency was analysed at two Western Australian iron ore concentrators. Efficiency data had hitherto been difficult to accumulate due to the high cost of analysing representative, and therefore large, coarse ore samples. To overcome this problem, recoverable density tracers, which are in effect artificial mineral and gangue, were manufactured in three different sizes (15 mm, 30 mm and 60 mm). Their use enabled partition curves to be studied within one hour of conducting a test: separation densities were generally lower than the feed medium density for all three sizes of density tracer. For a given set of operating conditions, the smaller tracers had lower separation densities and larger ecart probab/es than the large tracers. These phenomena are explained with the aid of a conceptual model of a drum separator, which assumes that the feed ore plunges to the bottom of the drum upon introduction. Particle rising velocities are, therefore, process determining.Medium rheology was altered by adjusting the proportion of solids in the pulp. This was accomplished by changing both the pulp density and ferrosilicon/magnetite ratio. Higher solids volume fractions invariably caused a decrease in separation densities and an increase in ecart probables, most markedly for the smaller tracers. A similar response was observed when feed tonnages were raised.An explanation for these phenomena is sought in the discussion which also suggests means of improving drum separator efficiency.

Jan 1, 1987