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By Menne D. M, Ladyman R

Camel Creek Mine operated by Lynch Mining Pty Ltd is located 65 km west of inghain and 160 kin north west of Townsville in North Queensland. (Figure 1). The Camel Creek gold mineralisation was discovered in mid-1987 in an area previously known for its tin workings. Mining commenced in January 1989 after an oxide reserve of 1.2 million tonnes @ 2.1 g/t gold had been delineated. The first gold pour was in May 1989. The mine developed into a medium sized open cut operation, with full site facilities. The initial mining rate was 500 000 tpa utilising run-of-mine (ROM) heap leaching to recover the gold. By the end of 1990 the wider orehodies were mined and efforts were focused on the narrow orebodies, of width typically less than three metres. Smaller earth moving equipment was employed to selectively mine the narrow orehodies leading to a decrease in the mining rate to 200 000 tpa. The Red Gold deposit (80 000 tonnes « 3.0 g/t to 18 in vertical) was mined in mid-1990 and ore was hauled approximately 8 kin to the Camel Creek heap leach operation. The ore was hauled in a dedicated campaign after being stockpiled. The cost of dedicated ore haulage ensured that only the more exceptional of the remote orebodies could be mined in this manner. The Golden Cup orebody, some 20 km from Camel Creek, was too distant to permit ore haulage. However, this prospect contained sufficient gold (initially 90 000 tonnes @ 3.0 g/t) to warrant the installation of a small mobile adsorption facility. Construction of the second heap leach operation commenced in late-1990. Gold production commenced in early April 1991. Mining of several smaller orebodies remote to the second heap leach facility has been undertaken and further mining is planned. This paper outlines heap leaching practice at Camel Creek Mine and summarises the success of the Golden Cup heap leach.

Jan 1, 1994

By Nekitel S, Arumba J, Kopi G, Findlay RH

The Kainantu area lies within the composite Scrapland terrane which is composed of Mesozoic metamorphic and intrusive units, overlain by Cenozoic marine sediments, volcanic and intrus-ive units and Quaternary fluvial sedi-ments.Four deformations (Dl, D2, D3, D4) are recognised within the Mesozoic sequences, which consist of greenschist to amphibolite facies schist derived from felsic to intermediate pyroclastic rocks and pelitic sediments. The second, third and fourth fold events are present in the Cenozoic sequence, and these rocks are broken by thrusts related to northwest trending D3 folds. South-dipping, possibly lystric, normal faults are recognised and may be related to uplift and exposure of the metamorphic rocks as core complexes.Known mineralisation in the area consists of gold and copper skarn deposits, porphyry copper deposits, shear-hosted gold deposits, epithermal vein deposits and gold placer deposits. Over 35 hard rock and 18 gold placer deposits are known within the area. Of significance are the Kathnell shear-hosted auriferous quartz veins; such structurally controlled veins may be more widespread than proposed prev-iously and offer a new exploration target.

Jan 1, 1994

By Woodcock J. T, Sparrow G. J

Activated carbon particles obtained from a number of Australian CIP operations were examined with an optical and a scanning electron micro- scope and an electron microprobe. External surfaces, and polished sec- tions through individual particles, were examined with special reference to materials on the surface and to calcium and gold distributions. Photographs are presented of surface contamination of the particles by salts precipitated from the pulp such as calcium carbonate (calcite), calcium sulphate (gypsum), and a magnesium salt; ore minerals such as quartz, hematite, pyrite, arsenopyrite, pentlandite, and various alumino- silicates; and other substances such as grinding media and a fungus. Calcite was very abundant but the other materials were less common. Contamination in the interior of carbon particles was almost exclu- sively calcium carbonate, and extensive contamination extended to the centre of some particles. A possible mechanism for the formation of cal- cium carbonate inside the carbon particles is noted. Gold X-ray dot maps of sections through carbon particles indicated that gold was distributed throughout coconut shell carbons and that although gold was more concentrated near the outer surfaces of extruded peat carbon particles, it was also present to depths of at least 500 ¦m. The gold distribution throughout the carbon particles was similar to that rf alrit~

Jan 1, 1988

By Mathew P. J

The CSIRO Division of Mineral and Process Engineering in Melbourne has been developing on-stream analysis sensors based on neutron and gamma radiation for better control of quality and process operations. This has resulted in the development of Ironscan, an on-stream analyser that measures the iron content of both lump and fine iron ore on conveyor belts. It can be mounted under existing conveyors with minimal modifications to the conveyor structure and can cope with steel cables in the belt. An interface gauge and an on-stream coal ash analyser have also been developed, both based on measurement of natural radioactivity. The interface gauge monitors the interface between liquor and mud in thickeners and washers, provided the natural radioactivity of the mud is sufficiently high to detect it above background. The natural-gamma ash gauge is a valuable addition to the Coalscan range of ash gauges. It is applicable to heavily laden coal conveyors or bins where the coal bed thickness exceeds 30 cm, and also to lightly laden conveyors, provided the coal is profiled on the conveyor.

Jan 1, 1991

The Kidston breccia pipe is situated approximately 280 km west northwest of Townsville, north Queensland. It is currently Australia's largest gold producer with production varying between 8,000 and 16,000 tonnes of ore per day. Current reserves are estimated at 36.2 million tonnes averaging 1.74 C/t Au and 2.21 g/t Ag. Alluvial gold in the gullies surrounding the deposit was first discovered in the 1880's and between 1907 and 1948 small scale open cut and underground mining was undertaken. Advances in extractive metallurgy and an increase in the gold price were major factors influencing the recent exploration and development of large scale mining of the deposit by Placer Pacific and Kidston Gold Mines. The breccia pipe is trapezoid in shape with surface dimensions of 1100 m by 900 m. Clasts show only limited evidence of mixing during brecciation, with the pre-breccia stratigraphy still discernible on the basis of clast types. This lack of mixing together with the intimate association with intrusive activity, suggests that the brecia formed by collapse, probably associated with the escape of a large volume of irothermal fluid from a crystallising hatholith. Mineralisation and alteration are also sratially and temporally associated with rhyolite emplacement and brecciation. Pre-breccia mineralisation consists of laminated stockwork quartz veins associated with muscovite, quartz and orthoclase-epidote alteration. Stockwork veins contain either anomalous molybdenite or gold. Uneconomic early stage post-breccia mineralisation and alteration consists of cavity infill quartz-epidote and calcite associated with potassic and propylitic alteration respectively. Economic late stage post-breccia cavity infill and sheeted veining consists of quartz-carbonate-sulphide infill associated with phyllic alteration. The grade of gold mineralisation generally decreases downwards in the system with an increase in the amount of pyrrhotite relative to pyrite. Pre-breccia stockwork quartz veins mineralisation is genetically related to the

Jan 1, 1987

By M Littlefair, D Gribble, R Rounsley, I Te

Low-density explosives (LDE) have applications where the explosive properties of ANFO are not well matched to the rock. In particular, rocks that are of low strength and/or well fragmented in situ. Dyno Nobel Asia Pacific (DNAP) has developed a new LDE, BlastLiteTM, which can be used as a cost-effective replacement for ANFO with excellent detonation characteristics. The product is based on ANFO with the addition of a bulking agent. The key to the product lies in the ability of the bulking agent to form a homogeneous blend with ANFO without the need for any emulsion matrix to bind the product together. This results in an LDE of low cost and high weight strength compared to existing commercial LDE products. The product has been trialled extensively and has proven to provide results that are equivalent to, and often better than, ANFO with reduced powder factors. This paper details the laboratory development and results of field trials for DNAPÆs LDE solution: BlastLite.

Jan 1, 2004

By J Krawcz, S Wasilewski, W Mironowicz

Barometric pressure and its variation in deep underground workings have a considerable effect on ventilation conditions. Pressure changes which create transient states of air flow and air parameters in workings are especially significant. Experiments have shown that pressure changes have a remarkable effect on air parameters at mine workings and hence, attempts to evaluate the scale of this phenomenon are of value. Continuous monitoring of the barometric pressure on the surface of mines allows for the detection of changes in pressure which undoubtedly influence alternations of pressure in the underground areas of mines. Very important factors are the internal disturbances of pressure within a mine ventilation system due to variable conditions of fan operation and the operation of a winding machine where a mine cage moving in a shaft causes piston like disturbances. Local transient disturbances caused by temporary opening/closing of air stoppings due to personnel or underground transport traffic are of importance. The results of over two years of observations of barometric pressure and its influence on pressure variation in underground mine workings are presented in this paper. The observations were possible through the installation of pressure sensors at selected points of the downcast shaft in a mine. Of interest are the observations of the transient states of pressure and other air parameters caused by emergency fan stoppage, movement of a mine cage and changes due to the opening of air stoppings. Data acquired during experiments of opening and closing air stoppings were used for the validation of a flow model in a long working.

Jan 1, 2005

Twelve years ago, Jeffrey Mining Machinery Division of Dresser Industries Inc. developed the 120H HELIMINER. This machine was the world's first fixed-drum continuous miner and soon became the standard among manufacturers of continuous miners throughout the mining machinery industry. This paper will first outline a brief history of continuous miner development, then discuss significant parameters which are essential to a successful continuous miner design, and finally describe a number of specific applications of Jeffrey continuous miners in a variety of materials, such as coal, potash, iron ore, and trona, around the world.

Jan 1, 1978

Data logged on mineral beneficiation processes during normal operation are analysed using time series (correlation and spectral) methods to identify the dynamics of the processes for on-line computer control. Recursive least squares estimation techniques are used to identify parametric models for a cassiterite flotation circuit and a coal washery. Identification problems such as the determination of model order, process time delays and the 'contamination' of the data by process recycle streams (feedback) are discussed. Typical results are presented in which optimised models are identified from data logged during normal operation.

Jan 1, 1985

The fast rate of development in the micro technology industry is enabling computer based systems to be used in ways never considered before. Micro technology can be used to great advantage in the mining industry to improve both safety and productivity. The planned use of electronic 'IN/OUT' boards at The Zinc Corporation, Limited and New Broken Hill Consolidated Limited (ZC/NBHC) mines will provide a much improved system for checking that the mines are clear before firing. The provision of remote ocaputerised core logging facilities made possible by small remote data entry terminals will greatly improve the productivity of the personnel involved in all stages of core Logging.

Jan 1, 1983

By Fuller P. G, Dugan K. J

Artificial support can be used to improve wall stability in open pit mines. This is examined for a particular case where the factor of safety for a slope is kept constant by using artificial support as the slope angle is increased. It is demonstrated that the savings in excavation generally exceed the cost of support. However, in order to correctly judge the eco- nomic impact of artificial support on the project, all the elements relat- ing to the use of artificial support must be taken in account.

Jan 1, 1989

By Shiels O. J

The major Permian coal deposits of N.S.W. are in the Sydney-Bowen Basin and associated small deposits occur in structurally isolated areas; a further deposit is present in the Oaklands Basin. - The Sydney-Bowen Basin in New South Wales comprises the sub basins, the Sydney Basin and the Gunnedah Basin. Coal measures in these basins are near the top of the Permian succession and within and below an underlying marine sequence. The coal deposits can be conveniently described in units in which the coal geology is homogeneous. The Clyde Coal Measures and Yarrunga Coal Measures contain no seams of economic significance and occur beneath the marine beds in the south of the Sydney Basin. The Greta Coal Measures are economically significant and represent a brief interlude in the marine sequence in the north of the Sydney Basin and equivalents are present in the east of the Gunnedah Basin. The Tomago Coal Measures crop out above the marine sequence east from the Lochinvar Anticline and dip southeast to uneconomic depths. The Newcastle Coal Measures are historically and economically very important and overlie the Tomago Coal Measures and these measures will continue to be important although future mining will be faced with greater depths. To the west of the Lochinvar Anticline the Singleton Coal Measures, equivalent to the Tomago and Newcastle Coal Measures, crop out. This unit represents the thickest development of coal measures in the State and has a very large potential for both open cut and underground mining. Equivalents of the Singleton Coal Measures, the Black Jack Coal Measures and the Booroomin Group crop out on the east side of the Gunnedah Basin and probably are widespread across the Basin. They have less economic potential than the Singleton Coal Measures. In the southwest of the Gunnedah Basin, Illawarra/Singleton Coal Measures crop out over extensive areas and possibly have a large potential for underground mining under low cover. The Illawarra Coal Measures are exposed along the western margin of the Sydney Basin and thicken as they dip into the Basin across a shelf. The outcrop area is currently mined and the shelf has considerable potential for future mining. The highest rank coals in the State are in the Illawarra Coal Measures in the south of the Sydney Basin. The deepest coal mining is in this area and its continuing success is of great importance to the future exploitation of the resources of the Basin. The Tomago, Newcastle, Singleton and Illawarra Coal Measures extend into and meet in the central area of the Sydney Basin but they are under thick cover and are not considered to be economic at present. Permian coal measures occur in isolated areas in the New England Fold Belt and have limited economic potential. The Oaklands Basin in the south of the State contains a large reserve of low rank coal.

Jan 1, 1975

By Cripps-Clark CJ

Sulphur partition between metal and slag has been examined on a cast-by-cast basis for BTIP furnaces. Partition values. were calculated from thermodynamic equilibrium data together with oxygen activities computed from the manganese partition. The S-C interaction coefficient, esc , was treated as an adjust- able parameter and the agreement between calculated and measured S partition values optimized. In the case of furnaces operating with low viscosity slags this procedure led to estimates of esc in close agreement with previously measured values. The same analysis applied to daily average data for several Kawasaki Steel furnaces led to the same esti- mates of e c s , indicating a similar approach to equilibrium. Silicon partition between metal and slag has been examined on a time average basis and found to be far removed from thermodynamic equilibrium for most Australian furnaces. A study of Japanese furnaces of comparable size reveals a temperature dependence of Si parti- tion which appears to be close to equilibrium. Australian furnaces approach this behaviour only when operating with low viscosity slags. A preliminary examination of the effects of burdening with TiO 2 on the silicon partition is also reported.

Jan 1, 1980

A relationship is predicted between oxidic nickel in slag, oxygen in matte and Ni/Fe ratio in matte after the examination of thirty sets of contiguous matte and slag samples taken from industrial nickel smelters. Oxidic nickel in slag is found to increase with increase in oxygen content of matte of constant Ni/Fe ratio, and it is proposed that the relationship may be used to predict nickel solubility in slag from a knowledge of matte composition alone.

Jan 1, 1979

The Fosterville goldfield, situated 25 km east of Bendigo, Victoria was at its peak between 1894-1910 with some 47 600 ounces produced (Figure 1). Since that time intermittent mining and tailings retreatment was undertaken until Bendigo Gold Associates delineated a viable resource and commenced an open cut heap leaching operation in early 1991. Unfortunately they encountered financial difficulties and Perseverance Exploration purchased the mine in April 1992. Perseverance operated a successful heap leach operation nearby Nagambie, 100 km east of Fosterville. Based on its acquired heap leaching experience, Perseverance Exploration was able to instigate operational changes to create a successful small gold heap leach operation. The major change was the using of the original multi-use leach pad as a single-use leach pad. The available data allows for a comparison of the two operating systems.

Jan 1, 1994

By Chamberlain A. C, Fisher N, Avraamides J

The thermal decomposition of sodium ethyl xanthate (SEX) adsorbed onto activated carbon was studied by coupled thermogravimetric analysis-Fourier transform infrared spectroscopy (TG-FTIR). Two discrete mass losses were observed, in the temperature ranges 100 - 230¦C and 200 - 340¦C. The same two gases, carbonyl sulphide (COS) and carbon disulphide (CS2), were the main gases evolved in each of the mass losses. Samples of activated carbon from two industrial plants were obtained and analysed by TG-FTIR. COS and CS2 were not detected in one of the samples. The other sample did show evidence of COS and CS2, which indicated that fouling of the carbon by SEX was still present. Other organic compounds were detected in the evolved gas stream of both samples, indicating the presence of organic reagents other than SEX.

Jan 1, 1996

The application of new and currently practised mining techniques in new areas and at greater depths necessitates considerable and immediate research effort. This effort is aimed at identifying the factors which make a particular method suitable and economically viable in a given geological, structural and operational environment. These factors, together with greatly enhanced knowledge of a deposit at the exploration and planning stage, allow selection of the most appropriate and efficient mining method in a new area such that coal resource recovery is maximised in a cost effective manner. Current research and future requirements for research into mining methods and associated equipment and mine services are reviewed.

Jan 1, 1981

Confirmation of significant mineable reserves of high grade silver ore at Elura Mine has led to the development of a high cost, high recovery mining system. At the contact of oxidised and sulphide ores lies a supergene zone of enrichment which has provided a contrast, not formerly imagined, to Elura's primary development and stoping operations. Because of the soft nature of the ore, intense ground support practice has been combined with a panel cut and fill continuous mining system to extract a reserve of small, but most valuable Proportions.

Jan 1, 1988

Between, 1980 and 1984, the demand for non- ferrous metals in the free world grew annually by 1.5 per cent for copper, 0.4 per cent for lead, 1.4 per cent for zinc, and 2.5 per cent for nickel. The growth rate decreased substantially compared to the rate experienced before 1980, and was far lower than the GNP growth during the corresponding period. The main reasons for this are considered to be 1. resource-saving efforts by industrialized countries resulting from the first and the second oil crises, 2. saturated demand for durable consumer goods, and 3. substitution of non-ferrous metals by new materials such as optical fibers.

Jan 1, 1986

Geostatistical analysis, resource estimation and three-dimensional modelling of the gold grade distribution was undertaken using exploration drillhole data taken from the Mt Leyshon gold mine. The main aims of the project were to provide an independent estimate of the primary gold resource and to improve the estimate by better understanding the statistical distribution of gold and the establishment of more robust variograms. These criteria have been achieved by the removal of low grade sub-populations, increased sample size and access to data from the most recent drilling program. The outcome of this statistical study has led to a lowering of the sill and nugget variance of the variograms used. Distinct geometric anisotropy was identified in all the resource estimation zones and was used to model gold grade distribution.Two independent resource estimates were established from the primary gold resource, one based on a geostatistical estimator (kriging) and the other on a traditional estimator (inverse distance weighting). Both methods were compared with a contemporary kriged estimate by Mt Leyshon Gold Mines Ltd.

Jan 1, 1993