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Geological information plays a significant, cost effective role, in the Mt Whaleback iron ore mining operations. The geology and structure are complex. Good communication between the Mine Planning Production Scheduling and Quality Control Sections is the key to utilisation of geological information to its full potential.Drilling and pit face mapping are the two basic sources of detailed data sets which are processed to prepare up to date geological cross sections and benchwise geological plans. This information is used directly for the blast pattern design and production scheduling. Physical ore type estimation is also undertaken. Orebody models are generated from the geological information.

Jan 1, 1990

By Zamel G. I, Zenari L. P

Technological developments in modem Tunnel Boring Machines (TBMs) and associated back-up equipment are offering significant alternatives for mining operators to consider, in the selection of equipment for coal mine development drifts, roadways, longwall gate roads as well as metalliferous mining declines and development drives.Greater flexibility in handling variable ground conditions, muck disposal and radius of turn as well as advance rates, are just some of the areas where modem TBMs can accomplish the flexibility that mine operators require to achieve cost-effective developments.Compact TBMs are achieving this acceptance because of the fundamental design of a shielded machine containing electrics and hydraulics within the forward shell, ability to achieve tight radius of curvature and grades, and ability to provide highly flexible support systems to meet all possible ground conditions.However, a single TBM design will not suit all mine developments, as each development method - while having common goals with all mine developments - will also require certain unique criteria to be fulfilled.

Jan 1, 1993

The Teutonic Bore deposit lies in a major greenstone belt within the Archaean Yilgarn craton of Western Australia. It occurs towards the base of a suite of tholeiitic basalts, some 100 m above a felsic volcanic pile of rhyolitic composition. Sediments comprise a minor, albeit important, percentage of the mine stratigraphy.The deposit consists of a single, steeply dipping lens of massive sulphides totalling 1.4 million tonnes grading 4.16 per cent Cu, 16.4 per cent Zn, 1.22 per cent Pb and 203 g/t Ag. In addition, cross cutting "stringer" mineralisation in the footwall contributes a further 0.75 million tonnes at 2.38 per cent Cu, 1.92 per cent Zn and 52 g/t Ag to the mining reserves. Principal primary sulphides in massive and disseminated mineralisation are sphalerite, pyrite, chalcopyrite and galena, while minor amounts of arsenopyrite and argentiferous tetrahedrite are also present. Weathering has affected the primary mineralogy down to at least 90 m, resulting in a strongly leached oxide profile to about 85 m, overlying a thin, erratic zone of chalcocite supergene enrichment.Lateral metal zoning is marked both in massive sulphide and stringer mineralisation, with Cu/Zn ratios decreasing away from the centre of the orebody. Alteration is well developed in association with footwall stringer mineralisation, changing from a central Fe-Mg carbonate, chlorite and silica alteration zone below the massive sulphides to an outer halo of sericitisation. The spatial distribution of these minerals is patchy. Geochemically, the footwall alteration zone is characterised by central Cao, Na20 and Sr depletion (with less regular enrichment of SiO2 , Fe and MgO), surrounded by a peripheral zone of K20 enrichment.Evidence supports a classic volcanic-exhalative origin, involving submarine discharge on the flanks of a rhyolitic dome and accumulation of the massive sulphides in a local palaeotopographic depression. The sulphides overlie their feeder zone as shown by alteration and stringer mineralisation. Tholeiitic wallrocks are thought to be genetically unrelated to the mineralising solutions, although their presence as a cap over the felsic volcanics may have permitted the build up of a circulating metalliferous brine system prior to sulphide deposition.

Jan 1, 1984

By Schiller J. C, Both R. A

Base metal mineralisation occurs at several locations within the regionally metamorphosed Kanmantoo Group on the southeastern flank of the Mount Lofty Ranges between Kanmantoo and Strathalbyn, 50 km southeast of Adelaide. Sulphide mineralisation is of three main types (Seccombe et al, 1985):1. copper deposits, at the Kanmantoo and Bremer mines, South Hill prospect and several minor occurrences,2. lead-zinc deposits at Aclare, Wheal Ellen, Strathalbyn, St. Ives, Scott's Creek, and Glenalbyn mines,3. pyrite-pyrrhotite mineralisation of the Nairne pyrite deposit and many other pyritic schist units within the Kanmantoo Group.Syntheses of folding, metamorphism and stratigraphy of the Kanmantoo Group were given by Kleeman and Skinner (1958), Offler (1960, 1963), Offler and Fleming (1968), Marlow (1975), Mancktelow (1979) and Parker (1986). Studies of the general relationships of mineralisation to structure in the Kanmantoo area were given by Grasso and McManus (1954), Mirams (1962), Poole (1969), and Lindqvist (1969).Several conflicting views on the origin of mineralisation in the Kanmantoo Group have been proposed. Thomson (1975) considered much of the mineralisation as a late-stage product of regional metamorphism and he, like Parker (1986) and Lambert et al (1987), stressed the importance of major lineaments as an ore control. However, Lindqvist (1969) and Verwoerd and Cleghorn (1975) tentatively suggested a syn-sedimentary origin to the Kanmantoo copper deposit and Jensen and Whittle (1969) and Seccombe et al. (1985) on the basis of sulphur isotope data proposed a bacteriogenic sulphur source and a sedimentary origin for sulphides in the Nairne pyrite deposit. The latter suggested that most copper deposits represent stockwork, vein or disseminated zones within subsurface vents whereas massive mineralisation at Wheal Ellen and Aclare mines probably accumulated on the ocean floor.This paper presents new geological information on the structural and metamorphic setting of the base metal deposits and attemptsto relate this information to previous regional studies of the Kanmantoo Group. Estimates of pressure and temperatureof peak metamorphic conditions based on silicate mineral stabilities are considered in relation to various silicate and sulphidegeothermometers which have not previously been applied to rocks in the Kanmantoo Group.

Jan 1, 1988

By Zervoudis J

Limitations of current touch-up solders for galvanised steel include coating thickness control problems and poor corrosion and abrasion resistance as well as health and environmental concerns due to toxic constituents such as lead. This paper reports on progress in ILZRO-sponsored research to develop an improved touch-up solder. Encouraging results were achieved in torch soldering trials with experimental zinc-tin-based alloys. Mouldability and coating thickness control were achieved over a practical working temperature range in which the solders consisted of a viscous mixture of solid primary zinc phase particles in a liquid zinc-tin eutectic matrix. The mouldability was dependent on the microstructure of the solder sticks, and optimum structures could be obtained through control of casting solidification rates and by the addition of small amounts of copper. Hardness, abrasion resistance, adhesion and corrosion tests on experimental Zn- (40 - 50 per cent) Sn-I per cent Cu also showed improved performance over lead-tin-zinc solders and compared the effects of tin content within this range. Atmospheric corrosion testing and optimisation of alloy composition and methods of solder stick production are continuing.

Jan 1, 1993

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

Jan 1, 1974

The Lennard Shelf is an Upper Devonian carbonate reef complex striking northwest for 350 km along the northeast margin of the Canning Basin. Numerous small Mississippi Valley type (MVT) Pb-Zn prospects occur within this belt, including the Wagon Pass prospect, located 105 km east of Derby in the Napier Range. At Wagon Pass, the base of the Upper Devonian sequence is a cobbly, dolomitic sandstone, the Van Emmerick Conglomerate. This is conformably overlain by the Frasnian to Famennian Pillara cycle Lower Napier Formation fore-reef deposits. These are characterized by red algal wackestones and terrigenous stylo- bedded packstones, with common dolomitization. The conformably overlying Famennian Nullara cycle contains a classic reefal assemblage, consisting of flat lying Nullara Limestone back-reef, fore-stepping massive Windjana Reef, and steep basinward dipping Upper Napier Formation marginal slope. The Nullara cycle is not dolomitized. The Wagon Pass mineralization is hosted by Lower Napier Formation dolomite. Mineral- ization consists of complex intergrowths and semi-massive assemblages of sphalerite and galena, with subordinate pyrite, marcasite, chalcopyrite, bornite, digenite, covellite and bravoite. Ore textures include granular and colloform. Gangue minerals are dolomite and very fine grained green chloritic clay. Although mineralization commonly occurs as reticulate fracture fillings, its overall distribution is stratabound. Ore paragenesis involved early "diagenetic" dolomitization, followed by breccia formation with chloritic and granular dolomite matrices. Main stage galena-sphalerite mineralization then occurred, accompanied by pervasive chloritization of silty units. Ore genesis was probably related to basin-derived "oil field" brines, with open space textures in the mineralization quite comparable to textures seen in Canning Basin dolomitic hydrocarbon reservoirs. Fluid inclusions in the host dolomite have typical MVT homogenization temperatures of 70-1150 C, and contain minor organic phases. The Van Emmerick Conglomerate, with its high porosity, dolomitization and weak Pb-Zn anomalism, was probably the aquifer for the mineralizing brines. Access of ore solutions to the Wagon

Jan 1, 1986

By J Naude

The TauTona (Sotho for Great Lion) Mine near Carletonville, which is one of AngloGold AshantiÆs most profitable operations in South Africa, has started a multi-million dollar expansion project that is expected to extend the operational life of the mine by at least three years. The project will also secure some 1900 jobs for existing workers and contract workers. The $US140 million project entails the development of the orebody to a record depth of almost 4 km underground. It means that TauTona, which already mines gold at the deepest levels in the world, will deepen its mining activities from 3600 m to a new record depth of 3910 m. There is great anticipation about the expansion program, especially because of new technology that will contribute to a safer working environment. It includes a simplified hoisting system that will minimise safety risks in conveyance activities. Due to the unique nature of this project, depth below surface and working through a three-tier shaft system, various innovative measures were incorporated into the planning of the endeavour. Special support equipment was designed to reduce cycle times and enable the crews to install the extensive support, prescribed by the mineÆs rock engineering department, right up to the face before every blast. Both declines dip at 23¦. The personnel/material (P/M) shaft is 4.4 m wide x 3.9 m high. This shaft is unique in that the conveyance will have an onboard driver. The rock shaft is 4.5 m wide x 3.6 m high. Rock will be hoisted with two, ten-tonne overturning skips. In both cases, P/M and rock, the winders were designed for the highest duty cycle, which is encountered during sinking.

Jan 1, 2005

By M McGeough

Following the success of calcrete sampling at Challenger, calcrete sampling has been widely adopted as the primary exploration technique for gold exploration, in the Gawler Craton. Calcrete is uniformly distributed over large areas and produces discrete gold anomalies. This allows drilling to focus on specific gold anomalous targets. However, despite widespread use of calcrete sampling, very little is known of the origin of calcrete in the Gawler Craton, and the link between calcrete gold anomalies and primary mineralisation. In an attempt to understand this association Lisa Gibbons recently completed an honours project at the Old Well Prospect approximately 45 km SSE of Tarcoola. Her work is part of a collaboration between CRCLEME, MESA and MIM Exploration. At Old Well, a calcrete anomaly (>10 ppb Au)covers an area approximately 7 km x 2 km with a peak value of 97 ppb Au. The study looked at the regolith as a whole, processes of its formation and nature of mineralisation within it. She was able to combine previous calcrete and drilling results with her own observations. The results from this study highlighted problems in relating surface calcrete anomalies to in situ gold mineralisation.

Jan 1, 1998

By T C. McCuaig, D B. Mapleson

The Wannaway Deposit is a structurally modified komatiite-hosted nickel-sulfide deposit. Until recently, nickel sulfide accumulations surrounding the Widgiemooltha Dome had been studied with a focus on understanding volcanological aspects of komatiite flow regimes and nickel-sulfide accumulation. Although volcanological features can be observed at Wannaway they are overprinted by several generations of structures associated with multi-phase deformation of the Dome. On the mine scale, two significant deformational events can be distinguished that control ore distribution. The first deformational event is represented by the formation of a layer parallel foliation within the footwall metabasalt and boudinaging of the ore into two distinct orebodies (mega boudins) during a north-south compressional event. Evidence of a second compressional event (east-northeast-south-southwest) is defined by reverse > dextral thrust-folding of the ore zone. The latter deformational event focussed the sulfide ore into thrust front positions where folded ore sequences are mined with stope widths up to nine metres wide. Later stage compressional and extensional deformation phases are observed but have minor, localised effects on the geometry of the ore zone. Four orders of control on the geometry and distribution of ore are interpreted through a combination of primary and secondary features observed at Wannaway. Extending the structural aspects of the secondary overprint features into areas of potential mineralisation has not only defined targets for extensions to the Wannaway Deposit, but has also aided to delineate high grade mineralisation and aid mining decisions. Obtaining an understanding of the volcanological conditions of formation, and more importantly, the structural evolution of the Wannaway region has been an integral part in optimising production.

Jan 1, 2003

By L Terrusi

The Bungaroo Valley hosts a concealed Tertiary channel iron deposit (CID) along a 17 km stretch of its length. Bungaroo Valley is approximately 0.5 km wide upstream at its easternmost extent, and 3.5 km wide downstream where it joins the Jimmawarrada Creek. The valley follows the axial trace of an anticline that plunges gently to the southeast, and the CID infills the valley. Mineralisation extends to a depth of 230 m below the surface, and almost the entire deposit occurs below the water table. Bungaroo Valley cuts through the Buckland Hills and is bounded to the north and south by steep scarps capped with the resistant Dales Gorge Member of the Brockman Iron Formation. Basement rocks are believed to be mostly Wittenoom Formation shales and dolomites, with Mount McRae Shale and Mount Sylvia Formation also present. Deep, localised depressions appear at the base of the CID sequence towards the north edge of the upstream section of the valley, while downstream the basal CID contact is relatively flat and shallow. In both cases the profile of the CID surface closely mirrors that of the basal contact. The localised depressions seen in the upstream basal CID contact produce significant variations in CID thickness of up to 100 m over short strike distances. This uneven palaeotopography is most likely due to eddying and waterfalls forming within the riverbed prior to CID deposition during a time when the water table was much lower than at present. It may also be associated with possible karsting in an underlying dolomite unit and subsequent syn- or post-depositional collapse of the overlying CID. The irregular basal contact of the Bungaroo CID sequence has implications for mining in terms of pit design and resource accessibility.

Jan 1, 2007

By H Allday

The mining industry’s attention has shifted over the last decade with the recovery from the downturn resulting in greater development of innovation and new work methods in a bid to remain competitive and deliver higher productivity. The emphasis on cost reduction to improve profit margins has primarily been the focus of the “work smarter” campaigns embraced within the industry. But is this strategy holistically the best-for-business, or does it place a ceiling on revenue opportunities and inhibit mining companies from truly maximising value? Businesses need to maintain a balance between active cost management and revenue generation often resulting in cost reduction strategies at site level. These strategies have merit, assessing areas of cost wastage across operations and creating space for opportunity. However, this potentially can create distractions from the goal of enabling growth and lead to the sacrifice of quality and delivery. Focusing too heavily on cost reductions without addressing revenue generation is an unprofitable lens to look through, and the relationships between cost, revenue, quality and profit margin can often be overlooked resulting in missed opportunity to maximise value. How these relationships are effectively employed by mining companies to reap the rewards from an overarching corporate perspective down to site level remains a fluid concept depending on the nature, operating market and strategy of the business. A common directive from businesses to their operations is to strive for greater profitability and productivity. The quantification of these requirements, and the nature of the cascading message delivered, impacts the methods employed by the operational team to meet the expectations of the business. Cascaded strategies, if not delivered with appropriate participation and buy-in can often be perceived to be knee-jerk and create frustration for operations who are squeezed to deliver on expectations by slashing site costs. This squeezing is not only felt by the mining operation but at the individual level and can result in increased team stresses. In some cases, this may also steer behaviours towards activities that result in corner cutting and an elevation of operational risk, potentially increasing associated incidents and injury. Driving down costs by any means can create an unhealthy tunnel vision where value is no-longer assessed for best-forbusiness results. By flipping the viewpoint to a value-based approach revenue opportunity may be realised and potentially exceeded, however this opportunity may be missed if value is over shadowed by a cost heavy focus. By analysing a selection of real operational cases (ranging from mining contractors through to in-house mining giants), it becomes apparent that practical revenue maximisation strategies are not only key to an increase in value and cash flow but to a stronger understanding of business drivers for sites and operators alike. In the cases evaluated additional revenue opportunities are foregone in favour of cost reduction strategies resulting in negative impacts on the associated operations and wider businesses. Alignment towards value generation is king. If strategies are not implemented focusing towards value and revenue maximisation, the opportunity loss experienced by mining operations could continue be great and the question should be posed; when the next up-turn hits will operations be ready to reap the rewards or still have a glass ceiling above their heads?

Mar 15, 2021

By Richmond A

Like many industries the coal mining industry has, since the beginning of this century, undergone many changes. Technological advances and the increasing demand for fossil fuels have introduced new mining methods and techniques which allow the extraction of thicker and deeper coal seams at higher rates of production. Most new methods of mining (or for that matter any other processes) introduce problems which the engineers of the industry are expected to face and resolve. Unfortunately, spontaneous combustion has plagued the coal mining industry since the first attempts to mine coal, and is no doubt partly responsible for the reputation that coal mining is a hazardous industry. The financial loss and toll of human lives due to the occurrence of spontaneous combustion of coal in coal mines is enormous, if not incalculable. Its occurrence today is less likely to claim lives, due to both improved methods of working and in the detection of spontaneous combustion sites.

Jan 1, 1983

By Sewell L. G, White H. S

OWING to two large falls of ground which resulted in serious accidents occurring towards the end of 1908, it became evident that the "open chamber" system then in use was unsuitable for the conditions existing in the Mount Morgan mine. It will be admitted that in all mining operations the first consideration is the economy of the system adopted, combined with its safety and ability to give the desired output. A sectional system with square sets has been introduced into the mine, in which due attention has been paid to these factors. In this paper a brief description of this system will be given. An outline of those previously used will be included, as it is necessary to understand the conditions which existed in the mine at the initiation of the sectional system. Outside the actual mining methods employed, various points that might prove of interest will be touched on.The square set system of mining has been in use throughout, the stopes in the gold ore in the upper levels of the mine since underground operations were started in Mount Morgan. In the oxidized zone the ore was of a friable nature, and in some cases rImning ground was encountered. In the lower levels the ground became heavier, and although the stopes were for the most part long, wide, high, and irregular, and not sectionalized, no difficulty was experienced in winning the ore, and no accident of a serious...

Jan 1, 1911

By Giuli M, Barnaba P, Sacerdote R, Tammaro F

Following a theoretical consideration of the effect of flooding, fluidisation and softening on blast furnace blowing limits, results are presented which show the effect of these parameters on operation. Industrial trials on Oscar Sinigaglia No. 4 BF are reported and results compared with those obtained theoretically and in the laboratory. It is shown that in these trials the furnace operated at levels of fluidisation very much (80-90%) below those theoretically calculated whereas in some cases (high proportion of sinter) actual hot metal output was near the calculated flooding limit. However, it was observed that as the sinter percentage decreases also actual productivity becomes lower than the one caused by flooding. This gap, which increases as other ferrous components (essentially acidic) replace the basic sinter was explained by the softening of the burden under bosh conditions. Softening indices measured on the individual materials yield support to this explanation. Coke rates data show that for approximately every one percent increase in the basic sinter in place of blended sized ore, a coke rate decrease of 1.1 kg/thm results. For acidic pellets this value is 0.6 kg/thm. Results of breakdown and reduction characteristics are also given and their indices compared with actual pt oduction. Measures to improve operations are proposed.

Jan 1, 1975

By Kobayashi M

Particulate chalcopyrite samples (78 ~ 98 mole per cent chalcopyrite, screen size fraction from 710 to 250 µm) were prepared by crushing and sieving lump ore samples from 12 locations in the Mt Isa Mine. Measurements of thennoelectric power (which does not involve the passage of a current) were made using a packed bed that was compressed by loading with a weight and placed in a temperature gradienL Details of the apparatus are described.The effect of particle size was investigated by preparing 12 fractions, with mean particle sizes ranging from 605 to 2.2 µm, from one of the ore samples. Values of thennoelectric power decreased with both increasing particle size and loading pressure; however it remained fairly constant for particle sizes above 80 µm, when loading pressure exceeded 3.3 MPa.Measurements of the chalcopyrite samples gave an average value of -260 JlV/K (-248 ~ -268 µV/K) for nine samples and about -290 µV/K for three samples, showing that these samples were all n-type semi-eonductors.

Jan 1, 1990

With the sinking of the No. 3 Shaft at North Broken Hill Limited, it was necessary to construct adjacent to the shaft a new changehouse for mining and surface personnel.It was also probable that as the older sections of the North and British leases were worked out, all employees at present working in these sections would be transferred to the No. 3 Shaft area. This could ultimately result in all personnel employed by North Broken Hill Limited being concentrated in this area, requiring the construction of new administration offices, workshops, mine store, etc., also in this area.

Jan 1, 1957

By Barnes GJ

The gabbroid-hosted nickel sulphide deposits of the East Kimberley constitutes one of Australia's most prospective emerging nickel provinces. Sally Malay Nickel NL (SMN), a wholly owned subsidiary of Gindalbie Gold NL, has established the East Kimberley Nickel Project (EKNP). The EKNP project tenements cover about 2000 sq km. The tenements cover the northern potion of a corridor containing mineralised or potentially mineralised layered mafic-ultramafic intrusions which includes the Ni-Cu-Co sulphide deposits at Sally Malay and Keller Creek. The Sally Malay deposit is located 225 km south-south-west of Kununurra (Figure 1). The sealed Great Northern Highway passes 3 km to the east of the deposit.

Jan 1, 1996

By Higuchi K

Intorducing the hypothesis that the cause ,òi spontaneous combustion of coal is depending un the accumulation of heat produced by its oxidation, the authors derived the equation expressing the temperature change in a heap i fine coal. To solve the equation, thermal conductivity, specific heat and rate of heat ,eneration of fine coal (-48 mesh) were measured at various temperatures in the range _'0-65¦C. The equation was solved numerically and the volume of fine coal which would ignite spontaneously was estimated as the function of ambient temperature. Using 170 Kg of fine coal, everal experiments for confirmation were conducted. At the ambient temperatures of 60¦C nd 50¦C, coal began to fire spontaneously brut 00 and 110 hours later respectively. Iii addition to this, the measured t,,rp,i,itures in the coal heap agreed with the ,aLulated ones comparatively well, If more volume of fine coal were used, experi;:ontul ;,eneration of spontaneous combustion from ...,n-, , 1-1 I'd Sill al r..

Jan 1, 1981

By Edmonds W, Giles C. W, Webb R. J, Gum J. C

Gold production from The Granites - Tanami Goldfield during 1993 is expected to exceed 8 t, eclipsing that of the traditional Northern Territory gold mining districts of Tennant Creek and Pine Creek. This is the result of dedicated and successful exploration, and the consequent discovery of new orebodies such as those at Dead Bullock Soak.Following granting of access to regional exploration areas in 1988 and identification of favourable host rocks in the Schist Hills area, North Flinders Mines (NFM) began a methodical exploration program of detailed geological mapping, rock chip sampling, costeaning and various types of drilling. The first resource of 600 000 t of 3.3 g/t gold was announced in mid-1989. This has grown progressively with systematic exploration to the currently published resource inventory of 6.6 mT @ 5.4 g/t, (as at 31.12.92) contained in six separate orebodies within the Dead Bullock Soak Mineral Lease at Schist Hills.

Jan 1, 1993