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Mineral exploration conducted over a wide area of the State during the period 1960 to 1973 has resulted in the discovery of a number of significant deposits. Base metals, particularly copper, have been of prime interest while, more recently, the search for uranium and coal have assumed import- ance. Expenditure of $27.6 million by companies during the period under re- view has located 580,000 tonnes of cop- per, 370,000 tonnes of zinc, 350,000 tonnes of lead, 24 million Kg of uran- ium oxide and 2,500 million tonnes of coal. A variety of other metals and non metallic and industrial minerals have been investigated in a diversity of geological environments.

Jan 1, 1975

By P Bethune

Back Creek is a tributary of the Condamine River. It flows in a northerly direction across the existing Commodore coal reserves. The diversion of Back Creek was proposed to minimise sterilisation of the reserves. The approval process required a Waterworks Licence application, under the Water Resources Act 1989 (Qld), for the construction of a stream diversion channel and floodway. The diversion was designed using the æreference reachÆ approach, which mimicked existing properties of Back Creek. The following design standards were developed for the diversion: the diversion corridor width was 500 m; the diversion geometry was specified for both the low-flow channel, and the floodplain; material properties were specified for both the low-flow channel lining and the diversion bund; compaction standards for both the low-flow channel and floodplain were set; and the diversion rehabilitation included a riparian corridor and pasture land with clumps of native trees and shrubs. The following performance criteria were developed for the diversion: velocity regimes were replicated for the design events considered, in an attempt to avoid increasing the diversion flow velocities in comparison with the existing creek flow velocities; sediment transport calculations indicated that no significant change in sediment transport was expected within the diversion; overburden settlement estimates for the spoil placed in the corridor were summarised, and will be monitored throughout the construction process; geotechnical stability of the proposed Eastern Pit Buttress and the diversion bund configurations was confirmed; and groundwater impacts were assessed. Construction techniques, monitoring and further investigations are also discussed in this paper.

Jan 1, 2003

By Sullivan BJK

The 1100 orebody is a massive copper sul- phide orebody which contains a major portion of the Isa Mine copper ore reserves of 130 million tonnes at 3.2%. The underground mining of a deposit as large as the 1100 orebody is technologically a complex operation as extraction strategies have to be evaluated with reference to 1. rock mechanics considerations, 2. safety and environmental standards, 3. production and operating require- ments and 4. metal recovery and costs. The mining philosophy in the orebody has undergone considerable change over the past five years as a result of experience and improved technology. At this stage, primary stopes are extracted by high rise sublevel open stoping and pillars by slot and mass blast drawn either under rock fill or as an open Stope.

Jan 1, 1978

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 Field R. V, Graieg O, George T. J

The design, construction and operation ofa laboratory scale rotary pot kiln are outlined. Charges ofup to 3 kg can be heated to temperatures up to 1200°C in a controlled atmosphere. Some examples of pyrometallurgical investigations carried out using the kiln are briefly described, including thermal reactivation ofcarbon using steam at 550-850°C, high temperature testing ofkiln liners for corrosion resistance to fluoride, and calcination oflimestone. Results obtained from these trials allow either direct scale-up to the Engineering Chemistry Laboratory's pilot-scale (50-100 kg/hr) rotary kiln or modifications to be made to commercial scale processes and/or equipment.

Jan 1, 1986

By D S. Clarke, W M. Prebble

Potential waste rock products from the mining of epithermal deposits in the Hauraki Goldfield are characterised to facilitate their management. Hydrothermally altered andesites and their weathered near surface equivalents have been examined from the Golden Cross, Karangahake and Monawai gold deposits. These materials vary in both their clay content (smectite, illite, kaolinite and chlorite) and the degree of silicification resulting from alteration and weathering. The simulated degradation (slaking tests) of waste materials cannot be explained purely by consideration of clay content, siliciflcation, or the resultant variations in porosity.   Microstructure is considered to be essential in predicting the physical degradation of waste rock. The scanning electron microscope is an effective tool in such an investigation. Increasing alteration results in clay particles becoming more randomly orientated (matrix microstructure); this causes a reduction in the surface area of contacts between components resulting in increased potential for degradation. The extent of skeletal microstructure (commonly characteristic of weathering) is an important control on effective porosity and the long term potential for degradation. Management requirements for these materials include the minimisation of moisture content variations (with the prevention of initial drying being of primary importance) and the containment of sediments produced.

Jan 1, 1991

By Ooms M, Scott OJ

This paper is concerned with the design and operation of storage and discharge facilit- ies for bulk solids handling. It presents an overview of the basic design philisophy emphas- ising the influence of bulk solid flow propert- ies and bin geometry on the flow patterns developed and how these, in turn, affect the reclaim efficiency and the bin structural in- tegrity and wear characteristics of both bins and chutes. The salient aspects of feeder design and operation will be discussed and the need to consider feeders as integral parts of the bin discharge system will be stressed.

Jan 1, 1978

Sampling and analysis of mineral deposits need to be executed without fear or favour of financial or personal impacts. Examples are given to illustrate the effects of departures, witting and unwitting, from correct use of appropriate techniques and/or equipment with emphasis on exploration and mining of porphyry copper deposits of the Pacific Rim. Some of the results of errors on the low and high sides of true value in exploration, resource or reserve estimations and in production caused by sampling and/or sample preparation mistakes, faulty practices, equipment and/or analysis are considered.

Jan 1, 2004

By D P. Telionis, P P. Vlachos, R-H Yoon

Industrial processes involving multi-phase flows such as flotation require understanding of the relationships between bubbles, solid particles and the flow. Modern experimental tools are employed in this effort to measure with great accuracy the basic features of the motion of all three phases in turbulent flow. We employed a unique digital particle image velocimeter (DPIV) that can record with great accuracy and kHz temporal resolution, velocity vectors of all three phases, namely the fluid, the solid particles and the air bubbles. The interaction of these three phases was studied in homogeneous isotropic turbulence generated by cylindrical grids. Particles and bubbles were released into the turbulence and the motions of the three phases were monitored. The experimental results obtained in the present work were compared with the predictions of the models published in the literature.

Jan 1, 2005

Investigations of the Mineragraphic Section; Commonwealth Scientific and Industrial Research Organisation, have included most of the known stannite-bearing ores in Australia, and have revealed several new occurrences of this relatively uncommon mineral. They provide information about its paragenesis, and its possible effect on tin recovery, that may be of general interest.Several of the investigations used in the preparation of this paper, were made in the first instance by pr. F. L. Stillwell or in collaboration with him.CASSITERITE-SULPHIDE ORES IN NORTH-WEST- TASMANIA Stannite is a minor component of most of the cassiterite sulphide ores of north-western Tasmania. These include the orebodies of Mount Bischoff, the Cleveland mine, Moina, the Stanley River district, Renison Bell, and the Heemskirk-Zeehan district, and form a well defined metallogenetic provence which is related to the Devonian granites of this part of Tasmania.In these ores mineralisation began. with deposition of cassiterite, a little wolfram, and quartz, topaz and tourmaline. With falling temperature, deposition of cassiterite ceased and arsenopy-rite, pyrite, and especially pyrrhotite, formed in abundance, tending to give massive sulphide ore. A little chalcopyrite; stannite, sphalerite and native bismuth accompanied the pyrrhotite. Deposition of quartz ceased after the pyrrhotite, was formed, and the later-formed nonsulphide gangue consists chiefly of carbonates and fluorite. With, the advent of the carbonates the pyrrhotite was altered to fine-gained intergrowths of marcasite and pyrite. Excess iron from the pyrrhotite entered the intergrown carbonate, or was precipitated as magnetite. Some solution of the cassiterite occurred at this stage, the tin being redeposited chiefly as stimnite replacement rims around the residual cassitellrite grains. Varying, but small, amounts of sphalerite, galena, tetrahedrite and silver minerals were depoSited at this stage, bringing the mineralisation to a...

Jan 1, 1951

A brief descri;tioki is given of nuclear power reactors and their fuels. These fuels are made from a variety of uranium compounds such as uranium dioxide, and uranium carbide as well as uranium metal and its alloys. The various processes used to produce some of these compounds from yellow cake are outlined. Using the natural uranium, heavy water reactor by way of illustration, fabrication of fuel elements is dis- cussed and the characteristics of U02 powder required for this partic- ular fabrication are indicated. The flowsheets and equipment presently in use overseas for production of this type of U02 powder are described. Possible areas where improvements might be made to this conventional process are enumerated and some details are then given of the programme of work which has commenced at the A.A.E.C. Research Establishment to gain experience in the general field of nuclear grade UO20

Jan 1, 1968

By I M. Platten, Y Xie

Narrow vein gold mineralisation generally contains both fine (<100 ¦m) and coarse (>100 ¦m) gold particles. The in situ size and shape, deportment, distribution and abundance of the particles controls deposit sampling characteristics, grade distribution and metallurgical properties. Particles can range from individual disseminated grains, clusters of particles and masses above 1 cm in size. At each end of the coarse-gold to fine-gold spectrum, the samplability of a deposit ranges from relatively simple for fine-grained disseminated gold particles, through to extremely difficult for very coarse particles. Deposits generally show a background grade of mineralisation dominated by disseminated fine gold particles. Drilling will resolve the background grade well, though is likely to considerably understate the grade related to the coarser gold particles. Gold mineralogy has a significant impact on metallurgy, with key factors affecting recovery being particle size, deportment, liberation parameters and silver content of gold minerals. For coarse gold particles the focus should be on liberation and the early removal of the particles from the mill circuit by gravity concentrators and gold traps. Finer particles will require more grinding to liberate prior to flotation or cyanide extraction. The determination of gold particle sizing is thus required to minimise evaluation and geometallurgical uncertainty and lower project risk.

Jan 1, 2008

By Yoshii Y

Many kinds of shield machines are being driven in the soft ground of Tokyo metropolitan area. Tunnel alignments for underground power transmission lines are generally planned to pass under public roads where facilities, especially life-line facilities, are densely located. Therefore, it is frequently required to drive the shield machines along very sharply curving routes. This paper reports on the performance of the new shield machine - the Sharp Curve Excavation Shield Machine - developed by Tokyo Electric Power Co., Inc., which can freely drive along a much sharper curve than conventional machines. Some of features of the developed devices of this machine are, maximum flexing angle of 6.5 degree in all deirection at the middle of shield body, maximum bending angle of 3.5 degree in all direction at the cutter disc, and so on. This shield machine can there- fore drive along curve of minimum radius 15m. The machine was confidently applied to the const- ruction of tunnel in soft clay strata at N values 2 to 5. Outer diameter 3.7m. Length 202m. Horizontal curve; radius 15m, length 20m x 2. Vertical curve; radius 30 m, inclined driven up 29%. The behaviors of the shield machine, segments and surrounding ground were monitored during construction for safety and efficiency check of this machine.

Jan 1, 1987

Tailings facilities tell a story to the public about how the mining industry manages its activities. They also create a risk that must be managed for the long term. All the knowledge and technology is available to safely design, build, operate and decommission tailings facilities.   Tailings at Waikato North Head Minesite are pumped as slurry, over long distances and against high static discharge heads to backfill the excavated area. WNH is, under the mining licence, obliged to reconcile the topography of mined areas to the closest possible resemblance of the original terrain. The active tailings areas are located near main operational facilities and detailed plans and procedures have been developed to ensure a safe and continuous operation.   The concentration plant is designed as two identical and independent plants. Each plant has its own tailings slurry pumping system.   This paper represents a general overview of the tailings disposal practice at WNH mine site. It discusses tailings delivery, construction and water management.

Jan 1, 2004

By Katom M

Each of the two 32 feet diameter Semi Autogeneous Grinding (SAG) mills at Ok Tedi's copper and gold concentrator was treating at best 1500 tph at about 65 per cent mill availability in 1988. The process was effectively unmeasured and used manu

Jan 1, 1997

The products from beneficiation present themselves at opposite ends of the spectrum, and yet numerous synergies exist in the preparation of coking coal and hematite iron ore products for their common export markets. Returning to the coal side of the business with Anglo Coal following a five-year sojourn in WA with Hamersley Iron, has provided the opportunity for comparing and contrasting some of the key synergies of the supply chains of both bulk commodities.Comparisons include consideration of things like: resource evaluation (especially quality aspects), run-of-mine handling and preparation, beneficiation, product handling and transportation, quality assurance and customer awareness, value-in-use and impacts on iron and steelmaking, and supply chain environmental aspects.Inherent within these are several other notable contrasts including: æseamsÆ and æorebodiesÆ, rocks and minerals, rejects and tailings, oxidation and weathering, suppliers and users, and marketing and purchasing, to name but a few.This paper covers some of the more interesting of these synergies and raises some potential opportunities for sharing knowledge and innovation between the two areas of activity in the future.

Jan 1, 2005

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

By Smith CB, Boxer GL

The Argyle diamond deposits in the East Kimberley were found as a result of a long term exploration programme, begun in 1972 by the Kalumburu Joint Venture (KJV), to search for diamonds on the Kimberley craton. When CRA Exploration Pty. Limited joined the KJV in 1976, it was re-named the Ashton Joint Venture (AJV). The Kimberley craton was considered prospective by analogy with structural settings of diamondiferous kimberlites in Africa. Diamonds were found during regional drainage sampling in Smoke Creek in late 1979, which led directly to the discovery of the rich Argyle lamproite diatreme (AK1) and associated alluvial deposits of Smoke and Limestone Creeks. The diatreme intruded into quartzites, sandstones and shales of Adelaidean age, and consists predominantly of lapilli ash tuff, with minor coarse and fine ash tuffs, 'non-sandy tuff' and olivine lamproite dykes. Erosion of the diatreme has produced the alluvial deposits of Smoke Creek and Limestone Creek to the north and east. Argyle diamonds are of predominately industrial quality, and the typical diamond is a brown, irregularly shaped, frosted, heavily resorbed form with abundant graphite inclusions, well developed etch channels and prominent hexagonal surface depressions. The pre-feasibility evaluation of AK1 comprised diamond drilling, surface and underground sampling, metallurgical sampling, marketing studies and ore reserve estimation. The proven AK1 ore reserve is 61Mtonne at 6.8ct/tonne. Evaluation of the alluvial deposits gave results of Upper Smoke Creek, 580 000 tonne at 4.6ct/tonne and Limestone Creek, 1.7Mtonne at 3.5ct/tonne. Commercial production from the two alluvial deposits began in 1983 with production for the year reaching 6.2 Mct. Mining of the alluvial deposits at three to five Mct/year is proposed to continue until the start of mining of the AK1 deposit in late 1985 or early 1986 at which time a new processing plant and associated infra- structure will have been constructed adjacent to the AKl deposit in the Limestone Creek area. Production is planned at three Mtonne/year, producing 25Mct/year, which will make Western Australia the largest producer of natural diamond (by weight) in the world.

Jan 1, 1984

By A F. Cooper

The northeast-southwest trending ~25 km2 area incorporating Bald Hill is located 18 km northeast of Haast, and 5 - 7 km west of the Alpine Fault in South Westland, New Zealand. The geology consists of Greenland Group greywacke overlain by a Cretaceous-Tertiary sedimentary sequence and fluvio-glacial/marine terrace deposits of Quaternary age. Alluvial gold in Cole Creek, draining west from the summit of Bald Hill, may be derived either from vein mineralisation in basement rocks or from fluvial or marine terraces.   This paper focuses on the potential for in situ gold and base-metal mineralisation in sporadic, siderite-rich quartz veins that cut basement greenschist facies metasediments that have been overprinted by contact metamorphism.   Throughout the area, vein compositions are dominated by quartz and commonly feature zoned plagioclase. Alteration adjacent to veining within the contact aureole is dominated by 1 - 2 mm, coarse grained biotite, with small amounts of sulphide, and is pervaded by abundant siderite veinlets. Outside the aureole, wall rock alteration to veins consists of fine grained chlorite. Trace element XRF analysis has been used to ascertain base metal concentrations within samples of vein and alteration zones collected from throughout the area. Vein and alteration zone mineral assemblages containing <5 per cent sulphide, with low concentrations of As, Cu, Pb and Zn indicate low potential for gold and base-metal mineralisation in the Bald Hill region. Contact metamorphism of Greenland Group basement in the northeast of the region, is likely due to emplacement of a poorly exposed Cr- and Ni- enriched gabbro. The presence of biotite and andalusite in hornfelses indicate contact metamorphism occurred at temperatures >350¦C and at depths <10 km. Widespread vein distribution does not appear to be related to contact metamorphism or gabbro emplacement. Further research is required in order to establish the fluid source from which the veins were precipitated.

Jan 1, 2007

Mine closure is a legitimate element of the mining cycle and like mine development involves technical planning, permitting, and finally construction. Closure begins with the mine's operational footprint and transforms the site so that it meets the explicit requirements of the owners and regulators. Implicitly, the closure will increasingly need to meet the requirements of other interested parties such as the local community, workforce, and future land users. Golden Cross is the first modern mine closure in New Zealand. It operated for 6 + years as a mid-size gold and silver mine winning ore from both underground and open pit sources, and processing via a carbon in leach circuit including a cyanide recovery stage prior to tailings disposal. The mine is situated in a sensitive high rainfall environment, and is complicated by the existence of a large ancient landslide underlying most of the tailings dam and waste rock embankment. The regulatory process for mine closure in New Zealand is not clearly understood by operators or regulators alike. The Golden Cross mine was permitted under the Mining Act 1971 and closed primarily under the Resource Management Act. This switch of legislation, the parallel reorganisation of many government departments, and change in societal expectations with respect to long term environmental stewardship during the life of the mine resulted in the requirements of closure being significantly different to the expectations at permitting.

Jan 1, 1999