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By Russell F. M

Following the accident in the Peterson section of Mufulira mine in September, 1970, a method had to be found of extracting up to 300 000 tonnes of ore per month from this area without inducing caving. Sandfill mining methods were chosen, necessitating a plant capable of producing both cemented and uncemented fill on a large scale. The paper covers the design and construction of this sandplant which is thought to be unique for its size, as it incorporates three 3 000 tonne capacity settled storage silos, a 500 tonne capacity cement silo, mixing tanks and a control room situated underground. The plant is designed to handle an aver- age of 440 tonnes per hour with a maximum of 660 tonnes per hour for limited periods, delivering either uncemented fill or cemented fill in proportions varying from 1:6 to 1:30. The instrumentation and equipment necessary to give one man operation of the plant is described and the fill mining methods now in use at Mufulira are briefly outlined.

Jan 1, 1973

The New Southern Railway (NSR) involves the excavation of approximately 10 km of single bore tunnel from Tempe Reserve, Tempe, to Prince Alfred Park (PAP). PAP is located just south of Central Railway Station in SydneyÆs Central Business District (CBD). From Tempe Reserve the alignment takes the tunnel under Sydney Airport including the main north/south runway. Sydney Airport is approximately 8 km south of the CBD. The NSR is being constructed by a private group, the Transfield Bouygues Joint Venture (TBJV). Transfield is a major Australian contractor and the French contractor, Bouygues, is providing the soft ground tunnel construction expertise and is also responsible for the design of the concrete segmental lining. This paper sets out to present in some detail the issues involved in tunnelling under the airport and in particular under the north apron, the main north/south runway and the new elevated roadway. The paper concentrates on these three areas on the airport with an emphasis on the following. The risks involved and measures taken to minimise the risks in tunnelling under the International Terminal north apron (with Jumbo Jets parked immediately above). Secondly, settlement predictions, settlement and runway operation criteria and the actual settlements that have occurred on the main north/south runway. Finally, the criteria that was developed during the construction of the deep bored piers for the elevated roadway at the Domestic Terminal as the TBM passed through this area of construction activity.

Jan 1, 1999

By Haskard R. W

A method of raising has been developed at Cobar Mines Pty Ltd's CSA Mine which has achieved advance of up to 6 m in a single blast and raises are now developed which have averaged 4.2 m per blast. The method is a form of Long Hole Raising and is applicable to short raises of less than 50 m length. Blast holes are column charged and initiated sequentially with short delay detonators (millisecond). The equipment used to drill the raising blast holes consists of normal production drilling rigs and accessories and no other special equipment is required. The method has significant advantages in rates of performance and fits neatly into production drilling and blasting schedules. The method is also far safer than any non-mechanical or conventional means of Raising.

Jan 1, 1983

By Muller GP, van Deventer JSJ

A mineralogical analysis has shown that in the Hartebeesfontein ore studied, uranium is associated mainly with uraninite, sulphides such as pyrite and to a lesser degree carbonaceous material such as thucolite. Little could be learned from the literature regarding the mechanism of flotation of these uranium-bearing minerals. A wide variety of reagents were used so that conditions enhancing the flotation of either the sulphides, carbonaceous material, oxides like uraninite, or combinations thereof, were created. As could be expected, the xanthate based floats gave-better selective recovery of sulphides than oleic acid. A substantial fraction of the uranium is associated with pyrite, so that addition of oleic acid to a xanthate float did not enhance the recovery or grade of uranium. After a pre-leach with sulphuric acid in which the pH and Eh were controlled so as to destroy the uraninite, higher uranium recoveries were obtained for the combined float (xanthate, DTP and oleic) and the DTP float. This was most evident when iron was added before flotation. Roasting, which destroyed the sulphides and thucolite, caused a significant decrease in uranium recoveries. The uranium liberated in this way was obviously not flotable in the same way as the uranium liberated from uraninite. A small amount of iron (2 kg/t) added before milling resulted in slightly higher grades and recoveries of sulphur for xanthate based floats. Higher iron additions had a detrimental effect on sulphur recoveries. Even in the case of oleic acid the addition of small amounts of iron had a positive effect on the recovery of sulphur and uranium.

Jan 1, 1993

By Bromley JC

Eimco Great Britain, a division of Baker Mining Equipment Company, was contracted to develop a hardrock tunnelling machine in conjunction with British Coal. The objective: a machine to cut rock up to 170 MPa compressive strength yet retaining the flexibility of roadheader type machines. This flexibility to encompass mobility, wide range of excavation shapes and sizes, simplicity of design and use, compact size, and efficient cutting operation. Current roadheaders operating in hard material are characterized by: 1. Severe machine vibration 2. Bouncing of the boom away from the rock 3. Very high pick wear 4. Inability to sump head in bad floor conditions The reasons for this poor performance can be attributed in part to: 1. High speed of cutting head rotation 2. Inability to hold boom against rock while cutting variable hardness strata. To overcome the problems described, a new articulation method was developed utilizing four hydraulic rams to "lock" the boom in position on one axis and four hydraulic motors to rotate the boom for cutting via a turret arrangement. The slide mounted turret is hydraulically advanced for sumping into the face, independent of the machine base. To transfer cutting forces back to the rock, the machine base is held rigidly in the excavation by floor to roof or side to side rams. A cutting head mounted on the boom rotates at very low speed, but with very high torque.

Jan 1, 1987

By Plumridge C. L, Lynch J. E, Forresty R. J

The Amanda Bel Goldfield (new name) is an area of approximately 1000 sq. km centred 65km WSW of Ingham and 150km due east of Kidston (Camel Creek homestead to Ryeburn homestead area). Gold mineralisation has been located in tightly folded sediments of the Silurian Greenvale Formation as well as in the Early Devonian Kangaroo Hills Formation and the Early Carboniferous Clarke River Formation. The area is traversed by a major NW-SE structural corridor, with many of the numerous basaltic, andesitic and rhyolitic dykes of the region sharing a similar trend. So far fourteen gold-bearing zones have been located, all of which are new discoveries delineated by bulk cyanide leach sampling and subsequent geological reconnaissance. The region has undergone three periods of deformation with gold mineralisation introduced syn-D1, post D1 - pre D , syn-D and post-D2/D , thereby revealing an involved metall~genic history. Mineralisation types include Sb, Sb-Au, Sb-Au-As, Sb-Au-As (-Pb-Zn) and Au-As. Minor occurrences of W, Pb-Zn-Ag and Pb-Zn-Ag-As-Sn are also present as are alluvial (deep lead) tin Drosoects.

Jan 1, 1989

By McCarthy P. L

A distinctive feature of the goldfields of Victoria was the extrac- tion of gold from deep leads, that is the buried river beds of Vic- toria's ancient rivers and streams. It is estimated that about 265,000 kg of gold was produced from Victoria's deep lead mines which comprises about 11.5% of Victoria's total production of gold (Bowen, 1974). The significance of deep lead mining for Victoria, however, went far beyond its economic contribution to Victoria. If Profes- sor Blainey is correct it was the frustrations of mining gold from deep alluvial leads in Ballarat during 1854 which precipitated the Eureka Stockade (Blainey, 1963, 46-52). This event resulted in the implementation of a fair mining administration and was an emphatic statement of the rise of democratic movements in Australia. Much of the technology and skill for mining deep leads had to be developed locally because at that time no other major gold- field elsewhere in Australia or the world had gold deposits with comparable problems. Deep lead mining in Victoria was there- fore largely a home grown industry and the equipment for that industry was often designed and produced in Victoria.

Jan 1, 1988

By Large RR

Underlying the 15 million tonne, high grade Hellyer volcanogenic massive sulphide deposit of western Tasmania is an extensive, well developed, and well preserved stringer system. Pervasive alteration of the footwall mafic volcanics occurred as the hydrothermal system initiated. Mineralogical zoning exists within the footwall alteration pipe, with a central siliceous core giving way to zones of chlorite, chlorite-carbonate, sericite-chlorite, and finally sericite-quartz on the margins (stringer envelope zone). However, the alteration morphology and zonation is not symmetrical around the central siliceous core; eastward the alteration zones are steeply dipping and terminate abruptly under the massive sulphide, while westward they extend out under the ore body in a blanket fashion. Geologic evidence indicates that the pervasive alteration started with the development of sericite-quartz which was subsequently overprinted by chlorite and finally quartz-sericite as the hydrothermal system became focused towards the centre of the stringer system.

Jan 1, 1990

Attempt has been made to determine the nature of charge on activated carbon surface by studying the electro-kinetic properties of the carbon in the presence of cations, anions and aurocyanide solutions. The zeta-potential measurements were made in the presence of individual ions and also in combinations. The cations and anions chosen were those commonly associated with gold bearing ores in Kalgoorlie area. It was found that the iso-electric point of Norit Carbon was at pH 4.45; below this pH the charge was positive, while above, it was negative. In the absence of gold cyanide solutions and in the presence of individual cations the i.e.p. shifted to the alkaline range (pH 7.2-8.5) while in the presence of anions the i.e.p. was shifted to less than pH 3.5. In the presence of aurocyanide solutions, the iso-electric point was still in the acid region irrespective of whether anions or cations were present. The probable mechanism for such a behaviour has been attempted after measuring the specific conductivities of solutions before and after gold adsorption, by studies using the electron- probe-mirco-analyser, and S.E.M. on the carbon surface.

Jan 1, 1982

Australia is a highly significant hub in the global minerals business. This paper will present the results of global and national studies looking at the potential 20 to 30 year future evolution of the mining and metals industry.   Globally, the World Economic Forum launched a Mining and Metals Scenarios project in January 2009 to explore the question: 'How will the environment for the global mining and metals industry look in 2030?'. As part of a structured strategic foresight process, eight workshops were held across the world over the course of a year which brought together over 200 leaders from the private sector, government, academia and non-governmental organisations. The workshops were supplemented by personal interviews and guided by an international advisory board.   Critical uncertainties for the future of the industry were identified and compare extremely well with the outcomes of a national survey of AusIMM members identifying the key issues and drivers shaping the future of their operations. Global context was one of the most significant issues identified by The AusIMM membership, which is expanded in the World Economic Forum study in terms of: geopolitics; global governance; action on climate change; and economic outlook. More specifically, this global study developed three divergent yet plausible scenarios describing potential environments for the global metals and mining industry in 2030. These scenarios are compared with ground-breaking global foresight work coordinated by the Stockholm Environment Institute in the 1990s. The scenarios will help decision makers rehearse alternative futures, anticipate potential hazards and identify business opportunities - new solutions, new markets and new connections. The presentation will present these scenarios as a way of challenging thinking, testing established wisdom, and stimulating imagination about the business case for the mine of the future. As Marcel Proust put it, 'The real voyage of discovery consists not in seeking new landscapes but in having new eyes'. This is an ABSTRACT ONLY no paper was prepared for this presentation.

Jun 1, 2010

By Ward B

Central Colliery was developed to exploit large underground reserves in the German Creek lease. It was planned from the outset as a retreating longwall operation and is the first longwall mine in Queensland. Longwall mining is not new to Australia but all previous experience has been confined to the coalfields of New South Wales. There was no precedent for longwall extraction in the markedly different geological setting of the Bowen Basin in Central Queensland. Various investigations were thus carried out during the initial development of Central Colliery, prior to the installation of the longwall, to ascertain the geotechnical characteristics of the coal seam and the adjacent strata and to predict the performance of the heading and pillar design as mining proceeds to depth. Laboratory tests showed the coal to be weak with an unconfined compressive strength of 9.6 MN/m2. Site inspection and geophysical correlation revealed a shear zone and extensive intraformational shear planes in the seam. The latter were found to exert a controlling influence on rib reaction in the headings. This behaviour was predicted by finite element modelling of the development headings which indicated that mining induced stresses in the coal would be relieved by block movement of the ribs. A chain pillar width versus depth curve was established for yielding pillar design based on empirical and computational methods. This gave pillar widths from 25m to 48m over the proposed depth range of 150m to 300m. Finite element modelling of the 25m pillars chosen for the first gateroads confirmed the overall stability of the design but suggested that rib spall could be significant in the adjacent tailgate. (1) Chief Mining Engineer, Capricorn Coal Management Pty. Ltd., German Creek Mine, Queensland (2) Senior Engineering Geologist, Coal Division, The Shell Company of Australia Limited, Melbourne

Jan 1, 1986

LITHOPROBE is a national, collaborative research grogram with the general objective of understanding the teotectonic evolution of the North American continent through multidisciplinary lithospheric studies in carefully selected areas of Canada. Six transect areas are investigating Precambrian evolution, although only in two of these is the research well evolved. The Archean Kapuskasing Structural Zone in Ontario is confirmed as an upthrust slice of upper to mid crust exposed at the surface. The Late Proterozoic Keweenawan mid-continent rift is shown to be the deepest known rift on Earth and the Grenville collisional zone of Ontario and Quebec involves crustal scale imbrication and ramping of deeply buried rocks to the surface. Two transect areas are investigating Phanerozoic evolution. In the Newfoundland Appalachians the geologically defined tectonostratigraphic domains do not coincide with lower crustal blocks defined by seismic reflection data. The Southern Cordillera Transect in western Canada is examining the nature, timing and dynamics of the assembly of the Cordillera, and particularly the role of accreted terranes. Work in the eastern and central segments has extended the known western limit of the North American craton at least IOO km westward and crustal-scale ramps associated with metamorphic core complexes have been identified.

Jan 1, 1990

By Thirumalai K, Peluso R. G

The United States has more than 45 billion tons of economic coal reserves in seams above 10 feet thick and current underground production from thick seams represent less than three per cent of the total production. A tripling of underground production from thick seams is necessary within the next 10 years to meet U.S. coal production demands. An analysis of underground accident and production data is presented in the paper. A study of accident and injury distribution in different coal seam heights in the eastern and western part of the United States in seams ranging in thicknesses from 5 to 15 feet indicates that the seam thicknesses do not produce adverse impact on underground injury incidence. Accidents associated with roof falls and haulage account for about 70 per cent of underground mining injuries.

Jan 1, 1976

By Nevolina VG, Zakharova IB

The results of a study on the flotation of baddeleyite and associate minerals are presented, together with effective flotation reagents. Detailed microcrystallomorphological analysis of the benefication products were made to find out the features of distribution of different baddeleyite generations between froth and chamber products. To reveal the dynamics of interaction of technological properties of minerals with their morphology and constitution, a method of onthogenetic analysis was used. It is well known that the difference between technological properties of the particles of the same mineral depend greatly on its genesis, but also the relation is direct - by means of constitution (habit). Thus, flotation behaviour of minerals depends on morphology microinclusions, distribution of impurities, dislocations and physical properties of individual particles. The microrelief of baddeleyite grains and crystals from froth and chamber products was studied with an electron scanning microscope. Chemical composition was determined by means of laser, microprobe and chemical analyses. The difference between baddeleyite generations, their distribution in benefication products, and the effects of grain sizes, number of inclusions and chemical compositions were valuated. Conclusions on baddeleyite flotation properties were made. Mineralogical study on eudialite grains from rough ore and eudialite concentrate was carried out. The interrelation between eudialite and associate minerals and negative effect of aegirine on technological properties of eudialite were revealed as well.

Jan 1, 1993

By Scott IR

In stratigraphic orebodies, estimation of footwall and hangingwall location is often of more importance than grade estimation. Contoured grade estimates often produce smeared boundaries and the use of accumulations and thicknesses as variables re-introduces the original problem: location of the point at which the estimate is to be made. The paper introduces statistical and geostatistical techniques for the solution of the problem and illustrates the techniques with a case study from Mount Isa, one of the world's largest producing silver-lead-zinc deposits. Solutions for calculating variograms in orebodies of variable dip, strike and plunge are presented together with relative variograms for individual metals, metal accumulation and orebody thickness. Optimal methods for hangingwall and footwall location are introduced and illustrated with an example. Orebody boundaries are then kriged after which individual metal grades are kriged within the estimated boundaries. The boundary estimates are compared with manually interpreted boundaries and known boundaries in mined-out areas. Grade and tonnage estimates are compared in mined-out areas.

Jan 1, 1986

Conventional narrow vein mining, utilising hand held methods, is expensive and requires specialised miners who are becoming a rarity. Hand held mining techniques (shrinkage stoping, leading stoping and cut and fill) have the advantage that they can be selective. The methods allow continued sampling of the face, control of hanging wall conditions and are adaptable to changes in strike and dip. On the other hand, more productive longhole stoping methods can allow excessive dilution due to drill hole deviations and changes in orebody dip and can be subject to unexpected hanging wall or footwall failures. Development of small scale equipment (as narrow as 0.8m wide) used for drilling or bogging very smallaccess drives has been ongoing over the past decade. In this paper, types of equipment are examined and compared, particularly with respect to their produc- tivity, size, and working environment. The introduction of electric hydraulic equipment has provided a better working environment with reduced noise, exhaust fumes and heat. The concept of the "hydraulic cherry picker" may have application in mining steeply dipping orebodies. The system requires orebodies to be reasonably consistent in dip over 15 metre sub-level intervals. The system involves the basic concept and skills of machine and airleg mining, combined with the safety and productivity of a mechanized work platform. The platform or basket is stabilized between the hanging wall and foot- wall by hydraulic rams and is extended by a tilting hydraulic boom mounted to a small prime mover or trailer. Design concepts (including remote controlled charging of explosives, adaptation to the boom for rock cutting and the overall electric hydraulic mining concept) are put forward in the paper as a view as to how narrow vein mines will be mined in the future.

Jan 1, 1987

By Mimura K

The carbon reduction of tantalum pentoxide was investigated in a plasma-arc furnace. The sample was a mixture of tantalum pentoxide and graphite, vacuum pressed into a briquette and was reduced at about 3100¦C. Argon was used as the are gas. The optimum mixing ratio of carbon and tantalum pentoxide, C/Ta205 is 5.10--5.15. The sample, weighing 7 g is fused within 60^ 70 seconds by plasma-arc heating and the reduction of molten tantalum oxide with solid carbon pro- ceeds rapidly to approximately 99.5 % Ta during this period. The reduction that follows in the molten state is slow. Within about 10 minutes, the maximum tantalum content of the massive metal product reaches 99.9 % and the oxygen and carbon remaining in the product are 50 ppm and 400. 500 ppm respectively.

Jan 1, 1980

By Cotton R. E, Cox R

Digger Rocks is one of several nickel-bearing sulphide deposits localised within komaLiitic volcanics of the Forrestania Greenstone Bell within the Archaean YiIgam Block of Western Australia. Exploration and evaluation to April 1990 have delineated a resource, at a nominal cut-off grade of 0.5 per cent Ni, of 1.9 Mt at 1.1 per cent Ni within a lensoid sulphide body which strikes NW, dips 50°SW, and occurs at a depth of 30 - 110 m below surface. There has been no production from any of the Forrestania nickel deposits to-date. The deposit, comprising both disseminated and massive sulphides, has maximum dimensions of 400 m strike, 115 m vertically and 90 m true width. Generally the massive sulphides occur at the base of the disseminated sulphides, on or close to the base of the Digger Rocks dunite. The two main massive sulphide lenses have maximum dimensions of 120 m strike, 75 m vertically and 16 m true width (northern lens) and 60 m strike, 25 m vertically and 4 m true width (southern lens). The average grades of the massive and disseminated sulphides are 5.9 per cent i and 1.2 per cent i respectively. The massive sulphides generally have sharp hangingwall and fOOlwall contacts and display strong internal grade anisolropy.The massive sulphides are mainly within the supergene zone and consist of violarite, pyrite and marcasite. The disseminated sulphides are mainly within the primary zone and consist of pentlandite, pyrrholite, pyrite and minor chalcopyrite. Alteration zones, up to six in number, are complex in detail. The sulphides are capped by an average of 30 m of sub-economic, leached, siliceous, oxidised material.A genetic model for the deposit is described which places Digger Rocks in Category 2 (sulphides in large layered dunite bodies) of the latest classification of komatiitic nickel sulphide deposits in the Yilgam Block of Western Australia by Hill and Gole (1990).

Jan 1, 1992

Western Mining Corporation has grown from a small gold exploration and mining company, funded by large established mining companies, into a large multi-commodity and multi-national mining company with shareholders who no longer have the same understanding of mining as the founders. Ore reserve calculation methods and reporting procedures have gradually changed throughout the group during this growth. These changes have been led by the newer mines, in particular the Kambalda nickel mines, where the need for more global, less conservative reserves were required to justify capital and forward sales contracts and to inform shareholders of the true worth of their company. This change in attitude to reserves has flowed back to the gold mines and has allowed a better informed management and investing public to plan for the future. Management of the calculation of reserves remains the responsibility of individual mining operations, but a corporate reporting and management structure exists through the office of the Director of Exploration and divisional chief geologists who strive to maintain standards of calculation and reporting. Specialist ore reserve geologists are starting to justify their place in the organisation, particularly at the larger operations. Reporting to the new AusIMM Standards is fully supported, although the amount of supplementary information requested will need to be considered carefully because of the large number of factors that make up even the simplest reserve.

Jan 1, 1990

The South Junction deposit of St Barbara Mines Limited was discovered in 1989 by the geologists of Ross Atkins Mining.The deposit occurs in the lower part of the Gabanintha Formation of the Lukes Creek Group in the Mt Magnet -Meekatharra greenstone belt. Country rock is predominantly talc-chlorite schist. Gold mineralisation is associated with north-south shear zones, quartz-carbonate-fuchsite alteration of the ultramafic rocks and in particular close to deeply weathered quartz-albite porphyry. For a detailed description of the geology of the South Junction Deposit see Fiala (1992).

Jan 1, 1993