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By Baynes F. J, Bermingham A. G

The 6000m long King Headrace Tunnel will be driven through hard Owen Conglomerate in the Eastern third and feldspar porphyry in the Western two thirds, with the anticipated hardness up to 350MPa unconfined compressive strength. Since the Commission had not driven a long, large diameter tunnel for some twenty years, major research was undertaken to assess the current tunnelling trends. Tunnel boring machines were compared with drill and fire equipment. Rail equipment was compared with rubber tyred equipment. Tenders were called with tenderers invited to submit alternatives if desired. Commissioning and production excavation using the equipment is discussed with the final conclusion being that the individual items of equipment purchased combined to make an efficient hard rock drill and blast system capable of progressing through all rock conditions likely to be encountered on the King and Anthony Schemes.

Jan 1, 1987

This paper describes a case history of using an integrated geochemical and hydrogeological approach to predicting solute transport from gold mine tailings in highly fractured volcanic terrain. Two modes of transport are identified, namely discrete fissure flow and diffuse seepage through the intervening weathered rock. A simple mass balance approach is used to predict concentrations at points of emergence because most of the seepage migration will be by way of the discrete fissures where advective transport will predominate. The mass balance method has been modified to allow for natural degradation of weak acid dissociable cyanide. The long term effects of diffuse seepage are also examined.

Jan 1, 1988

Roadheader tunnelling machines have been used in Australia by both mining companies and contractors involved in the mining and con- struction industries since the early 1970's. They have both advantages and limitations, and this paper discusses machine excavation from the point of view of a contractor who has both reaped the benefits and suffered the conse- quences of using roadheaders. The paper also includes brief descriptions of three projects tackled by roadheader, all the projects being Declines.

Jan 1, 1987

Consideration was given to the.applicab on of a solvent extraction circuit to be'included in the process'for the-recovery of a high grade product from.:-the Rum Jungle Creek.South uranium ore body.The economics of two alternative processes, firstly the Eluex process which uses an ion exchange process followed by solvent extraction.-of a.high grade sulphuric acid eluate, and secondly a process using direct solvent' extractioh of pregnant leach liquor, were studied. There was a small cost advantage favouring the Eluex process but when other factors were considered, the installation of a direct solvent extraction process appeared the better long term investment. A solvent extraction plant was installed at Rum Jungle in 1962.

Jan 1, 1963

By Bertrand D. L

Although investigations into treatment of Mt. Keast (a hill of tailing) began as early as 1940, it was not until the Imperial Smelting Furnace (I.S.F.) was installed at Cockle Creek by Sulphide Corporation that its treatment became eooncmically feasible. Early investigations and milling operations which began in mid-1976, with their developments are described. Metal recovery involves sulphide flotation, oxide flotation and gravity techniques.

Jan 1, 1983

This address is set deliberately in the broadest possible terms. A review of the place of mining in Australian life today will serve to point up the changes that we can see in the life of people in the industry. Some of the influences on the future welfare of mining people bear also on the progress of this Institute, now approaching its 90th year. As mining becomes more and more dependent on higher technology and therefore, on the higher skills of the people in the industry, the role of The Institute, I suggest, becomes more and more significant.With investment per employee in mining generally continuing to rise, our ability to handle problems of manpower and human relations becomes a matter of greater importance.Questions that flow from these general thoughts form the substance of what I have to say.

Jan 1, 1982

By Carter J. P

A two year study into the effects of coal mining induced subsidence on cliff lines was undertaken by the Department of Mineral Resources with the support of a grant under the National Energy Research, Development and Demonstration Program. A new monitoring technique, using an Electronic Distance Meter and acrylic reflectors attached to the cliffs, provided safety for the surveyors and extensive and accurate three dimensional displacement data on the movement of the cliffs as they were being undermined. The study report included many graphs showing the measured vertical and horizontal displacements, differential subsidence, tilts and strains and included analysis of these movements with various parameters, such as, seam thickness, depth of cover and distances between the reflectors, longwall face and the edge of the chain pillar. Some of these graphs are presented in this paper and could be used, with caution, to predict subsidence movements around other cliff lines, after allowing for differences in geology and mining layout. A mechanism is suggested as an explanation for the observed high horizontal movements around the cliff lines. Sixteen percent of the overall lengths of cliffs that were undermined during the monitoring study fell and the contributions of various factors that appeared to influence the cliff falls are discussed. It is concluded that no single factor dominated as the major cause of the cliff falls and, often, many factors combined to cause cliff face instability.

Jan 1, 1992

By Thompson D, Burgess G. C

Subsequent to large scale trials in 1987, the installation of a submerged lance Sirosmelt furnace system was approved in late-1988 for the cupellation of retort bullion to dore silver. Commissioning work commenced in June 1990. During the process air is lanced into a molten slag bath contained in a cylindrical vessel to rapidly oxidise the granulated feed bullion from 15 - 25 per cent silver to rough dore grade. The process is now an integral part of the Precious Metals operation replacing the first stage reverberatory cupellation furnaces to achieve productivity improvements, lower silver inventory and increased silver Recovery.

Jan 1, 1992

Routine, in-pit geological mapping of highwall at Central Queensland Coal Associates (C.O.C.A.) deep strip mines has proved too slow for the increasingly greater highwall lengths which require mapping. This realiz- ation has encouraged the search for faster mapping methods and after trial of ground photographic methods has resulted in the adoption of interpretive mapping off stereo cover, oblique -- aerial photography. This entails using a Cessna 182 light aircraft flying at its slowest speed, the aerial meth- od finally employed consisting of two Vinten, air reconnaissance cameras mounted in parallel and simultaneously taking both colour and black and white photographs of the mine high- wall. The respective 1:500 scale enlargements produced from the 70mm format films combine to present the sharpest resolution attainable under the field conditions pertaining and such information on weathered material as only colour photography can fully render. Total costs for the aerial photography method are estimated to be about the same as those for conventional in-pit mapping. Whilst total costs are comparable, geo- logist's time for mapping a 10 km. length is reduced to less than half that for in-pit mapping (for Stage 1, fully accurate mapping) and accuracy and detail are greatly improved. A permanent, accurate record of overburden

Jan 1, 1981

By Morrison R. D, Davis J. J, Fraser B, Kojovic T

1991 saw the completion of a three-year $1.1 million research and development program in mineral sands beneficiation, funded in two associated projects by the Australian mineral sands industry through AMIRA, and carried out by the Julius Kruttschnitt Mineral Research Centre. It is believed to be the largest R&D project in mineral sands ever conducted by a university research group. It covered dry plant operation, and delivered several products to the industrial sponsors, including: ò A detailed characterisation of the radiation properties, mineralogy and size distribution of inhaleable dust arising in dry plants. ò New process models of magnetic and electrostatic separators. ò New on-line instruments for elemental assay (in association with AMDEL) and bulk conductivity measurements of dry process streams. ò Demonstration and evaluation of the Magstream magnetohydrostatic separation technology.

Jan 1, 1992

By Schmincke H-U

The Pleistocene basanite-tephrite Rothenberg cone complex was built by an alter- nation of strombolian and phreatomagmatic phases of explosive eruption. Two main centres, on a one km long NNE-trending fissure, were active during its construction. The strombolian deposits from three discrete facies corresponding to the crater-fill and inner wall and outer wall environments on the cone. The outer wall facies consists of an alternation of 1. 'normal' coarse-grained, relatively well- sorted lapilli and bomb beds, and 2. finer-grained poorly-sorted lapilli beds. Evidence suggests that the former was pro- duced by open-vent lava fountaining, with balanced magma supply and discharge rates, and the latter are the products of eruptions during partial blockage of the vent, by collapse of wall-rock, and formation of a degassed crust on the magma. The resulting explosions there- fore ejected a mixture of fresh actively ves- iculating magma, older partially degassed lava and material recycled from the wall of the cones. The phreatomagmatic deposits are an alternation of moderately-sorted fall beds and thinner ash-rich pyroclastic surge and rain-flushed units. The clast populations are much more diverse than strombolian ones, including abundant wall rock fragments from 0-100 m depth. The juvenile (magmatic) particles range from highly vesicular scoria to dense 'bread-crusted' clasts, and contain abundant small wall rock inclusions. The phreatomagmatic phases are products of explosive interaction of small batches of magma with shallow groundwater. Vesiculation of this magma played a small but significant role throughout the fragmentation.

Jan 1, 1987

By A Sinuhaji, H Kalangi, T B. Setyoko

Ore fragmentation at the DOZ block cave mine is highly variable, both as a function of rock type and column height of draw. Initially, the mine was constructed and equipped with limited capability to handle drawpoint oversize material. Significant issues with drawpoint availability and achieving overall mine production targets resulted. A suite of secondary sizing tools was added to the mine equipment fleet over a one-year time frame. Although significant oversize continues to be experienced, use of the correct secondary breakage tool for each particular oversize or hang-up occurrence has resulted in increased drawpoint availability, production rate, draw compliance, and operator safety. Currently, a range of secondary breakage techniques is being utilised to size material for delivery to the primary crusher. Run-of-mine material (3) is directly mucked to ore passes fitted with grizzlys that have one-metre square openings. Ore containing small boulders (>1 m3, 3) is loader-trammed to ore passes fitted with rockbreakers. Medium-sized boulders (>2 m3) accessible from the drawpoint are drilled with Sandvik Tamrock Commando drills. Boulders hung-up within the drawbell are drilled and charged with a Sandvik Tamrock Secondary Breakage Unit. Compacted, fine-grained muck is blasted utilising 55 mm cartridge powder concussion bombs.

Jan 1, 2005

Operations at two open cut mines have so far commenced on two out of the five potentially mineable seams in the Fair Hill - German Creek Coal Measures. Due to seam splitting, up to seven mining units are present in the Dysart Seam interval at Peak Downs giving a total of 12 mining units in the section. The coal is low to medium volatile type and produces strong coke. Rank increases and fluidity decreases in the southern part of the area.

Jan 1, 1974

By Jaczkowski B. M, Cox T. J, Domfeh I. A, Stalker I

Mining and treatment of gold ore in the Ashanti region at Obuasi, Ghana has been continuous for more than 100 years. Earlier production from this world class deposit can be traced far into the history of West Africa's gold trade. As part of a general development and expansion program, Ashanti Goldfields Corporation (Ghana) recently undertook a program to heap leach oxidized near surface ore. Kappes, Cassiday & Associates was given a major role in the design, equipment supply, installation and start-up management of the 3000 tonne/day heap leach. Unusual conditions included a high annual rainfall and an ore which could be characterized as a soft, decomposed, water saturated schist. Production began in March 1990. Startup problems and their solutions are discussed.

Jan 1, 1991

Material hardness and environmental factors can limit or restrict conventional blasting techniques and this has led to advancements in the performance and efficiency of ripping. Not all materials can be ripped, however today's technology and experience can help make a reasonable prediction. A ripping versus blasting decision will depend on the total volume of material to be moved, the production capabilities and costs of the ripping tractor(s) and on the size and relative efficiency of drilling and Blasting.

Jan 1, 1995

A comparison is made between bord and pillar and longwall coal mining. Longwall mining presents a challenge to raise the level of management and engineering practice. To maintain a competitive position in the world export market, the Australian coal mining industry must continue to use and develop the most advanced, cost benefiting, safe mining systems.

Jan 1, 1987

By Barnett J. C

The arid and semi-arid region of Western Australia occupies about two-thirds of the State equivalent to an area of about 1.8 million sqkm. Groundwater demand in this area has historically been linked to the pastoral andmining industries commencing with the gold discoveries in the Eastern Goldfields some 100 years ago. Substantial increases in demand have occurred in the past two decades initially as a result of nickel discoveriesin the early 1970's and more recently the rapid resurgence of the gold mining industry. Mineral exploration and development in the Great Sandy Desert at Telfer (gold) and Kintyre (uranium) and in the Great Victoria Desert at MulgaRocks (uranium) has also been accompanied by detailed groundwater investigations.

Jan 1, 1988

By R M. Hough, G Duclaux, M A. Pearce, M F. Gazley

"An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation. Microcharacterisation, such as that described in this paper, provides understanding of a mineral system at multiple scales, and understanding microscale variations is the key to understanding the large-scale variations in a mineral system. More than 50 high-grade lode samples from across Plutonic Gold Mine (Plutonic), Marymia Inlier, Western Australia were analysed by a variety of techniques, including micro X-ray fluorescence (µXRF) mapping, micro X-ray computed tomography (µCT), scanning electron microscopy (SEM), field emission gun SEM, electron back-scatter detector (EBSD), proton-induced X-ray emission microprobe and synchrotron XRF mapping. These data demonstrate that competency contrasts are the key to governing the location of Au mineralisation at Plutonic. Micro CT imaging of high-grade samples shows the Au filling in voids and pore-space in the rock, after having travelled along more permeable layers and already existing or reaction-induced pores formed during hydrothermal circulation. Using 3D visualisation, the Au is seen to form a connected network that appears undisturbed at the scale of the samples, and a high-grade Au deposition event was one of the last events to affect the rock. This interpretation is supported by SEM analyses on high-grade samples that reveal calc-silicate (epidote-clinozoisite) alteration that is not present in lower Au grade samples, which are typically dominated by potassic alteration, and that sulfides are typically less abundant close to the Au. The replacement of biotite by chlorite is an alteration associated with the high-grade Au-mineralising fluid. Gold is coarsest where Au particles are located on the margins of minerals, typically sulfide and quartz grains, suggesting the importance of rheological contrast at the microscale. Furthermore, EBSD data reveals that Au is undeformed and overprints peak metamorphic and retrograde minerals. Data confirm recent deposit-scale observations, suggesting that deposition of high-grade, visible Au was related to a hydrothermal fluid circulation event late in the geological history of Plutonic.CITATION:Gazley, M F, Duclaux, G, Fisher, L A, Hough, R M and Pearce, M A, 2015. High-resolution characterisation of gold mineralisation at Plutonic Gold Mine, Western Australia – evidence for the late-stage deposition of high-grade gold , in Proceedings PACRIM 2015 Congress, pp 51–58 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 18, 2015

By Arnold J. J

The design of a coal preparation plant using bore core data cannot be discussed without some reference to the wider considerations of design. A thorough knowledge of coal preparation processes and processors as well as ancillary equipment is essential if the coal properties determined from bore cores, are to be fully utilised. Whilst generalised information of processes is available from a wide range of publications and equipment suppliers for the intending plant designer, local operational experience must be taken into account where there are similarities. However it would be wrong to assume that satisfactory plant design can be achieved merely be repeating previous design parameters. A detailed examination of bore cores used in conjunction with well proven design 'criteria will identify important differences in design parameters without which efficient and economic plant/sectional sizing cannot be achieved.

Jan 1, 1977

This paper addresses the area of utilising automatic data capture systems in the metalliferous mining environment for the purpose of tracking personnel and vehicles, for both safety and productivity purposes.As automatic data capture systems in the form of barcodes have revolutionised the stock control procedures in retail establishments in recent years, so too will similar systems in the form of radio frequency identification products (an electronic version of the barcode) transform the way in which many aspects of mining operations will be managed.

Jan 1, 1992