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By Mauk JL, McOnie A, Simmons SF

Three cross sections, 200 m apart, display the distribution of indicator hydrothermal minerals across the Empire zone of the Golden Cross epithermal Au-Ag deposit, Waihi, New Zealand. These minerals are used to interpret the temperature and composition of hydrothermal fluids. The distribution of interstratified illite-montmorillonite and illite indicate that temperatures ranged from 140 to >220¦C, with temperatures above 220¦C predominating. The mineral assemblage of quartz-adularia-chlorite-illite-calcite-pyrite envelops the Empire vein system and stockwork, and reflects formation from an alkali chloride water, whereas the mineral assemblage of replacement calcite-interstratified illite - montmorillonite- kaolinite forms a carapace and reflects formation from a C02-rich steam-heated water. Alkali chloride waters appear responsible for the epithermal Au-Ag mineralisation.

Jan 1, 1995

Spatial data processing using geographic information systems produces qualitative results which are superior to those from other existing software tools. However, the answers to various quantitative questions in mining operations is often limited by the capacity of the GIS to process appropriate spatial data. The efficient operation of a large underground mine demands that an adequate GIS be put in place.

Jan 1, 1995

By Lang SC

The Broken River Province, in the northern part of the Tasman Orogen, is divided into the Camel Creek and Graveyard Creek Subprovinces. In the Late Cambrian to Early Ordovician, and again in the Late Ordovician, the northern part of the Tasman Orogen was probably a convergent margin with calc-alkaline volcanism. These episodes may have been separated by a passive phase in which quartz-rich flysch and tholeiitic volcanic rocks were deposited. Subsequently, in the Silurian, the region underwent extension forming a large turbidite basin which included the Camel Creek Subprovince and the Hodgkinson Province to the north. Melange is pervasive in the Camel Creek Subprovince which was folded twice in the Devonian. The melange may be related to thrusting accompanying D1. No rocks younger than Early Devonian have been recognised whereas, in the Hodgkinson Province, deposition continued until the latest Devonian. The Graveyard Creek Subprovince formed adjacent to the Camel Creek Subprovince, probably as a pull-apart basin on stable crust. The deformation history of the Graveyard Creek Subprovince contrasts markedly with that of both the Hodgkinson Province and Camel Creek Subprovince. In the Graveyard Creek Subprovince, melange is only present in Early Ordovician rocks. No major angular unconformities have been recognised in the overlying marine to non-marine sequence, which ranges from Early Silurian to Early Carboniferous. Several hiatuses and a slight angular unconformity, all within the Devonian, may be related to the major events in the Camel Creek Subprovince. A major deformation in the Graveyard Creek Subprovince in the Early Carboniferous had only slight effects in the Camel Creek Subprovince. Movement on the Clarke River Fault was probably an important influence on sedimentation and deformation in the Broken River Province.

Jan 1, 1990

Selective open pit mining for gold has been in progress at Harbour Lights since the onset of mining in March 1985. Selective mining techniques used are similar to those in other recently opened gold mines in Western Australia. However certain practices have been introduced to accommodate the irregular distribution of mineralisation and comparatively high mill tonnage throughput. These include selective mining with large bucket excavators, sequential waste stripping - ore mining normal to the strike of the orebody and sample line preparation and ripping on bench floors. Application of these selective mining practices at Harbour Lights enables the operation to maintain delivery of approximately forty by 50-tonne truck loads of ore to the mill crusher everyday, with limited rehandling of material through ore stockpiles.

Jan 1, 1986

By S Hapugoda, A Edenton, M Adam, R J. Holmes, J R. Manuel, R Smyth

Lump ore is one of the key ferrous feeds used in the blast furnace ironmaking process, normally accounting for ten to 20 per cent of the blast furnace burden. Like other feeds, the characteristics of lump ore have an important impact on the stable operation and productivity of the blast furnace. Lump ore is usually assessed chemically, physically and mineralogically to establish its likely blast furnace performance. The physical characteristics of lump ore are strongly related to the chemistry, mineralogy and texture of the ore involved. In this paper, the blast furnace ironmaking process is reviewed, with particular emphasis on the key quality requirements for the ferrous burden material. A variety of key physical characteristics of lump ore measured using standard and non-standard methods are then described and subsequently correlated with the chemical and mineralogical characteristics of the ore wherever possible. Finally, the impact of these physical characteristics on blast furnace operation is assessed.

Jan 1, 2009

It is proposed to deal with those raw materials which are produced in South Australia to meet the needs of the country's steel industry. They are chiefly, iron ore, limestone and quartz.Iron ore and limestone are fed to the blast furnaces of Newcastle and Port Kembla together with coke to produce the hot metal charge for the open hearth steel furnaces.They are also qsed in the raw state in the steel furnaces to assist in the conversion of the hot metal to steel. The iron ore is quarried from' Iron Knob and shipped from Whyalla to Newcastle and Port Kembla, whilst the limestone is supplied from the deposits at Rapid Bay and shipped in the same manner.Quartz is used in the manufacture of ferro-silicon, an alloy which is added to the ladles of molten metal tapped from the open hearth furnace in the case of almost every grade of steel. It is obtained from a quarry situated between Iron Knob and Whyalla, and shipped to Newcastle.IRON OREWith the exception of several small quarries situated at Breadalbane, Cadia, Cowra, Crookwell, Michelago, Jerrawa and lerraama in New South Wales, the iron ore requirements of Australia's steel industry to date have been met from Iron Knob and the Middleback Range in South Australia.Several of the small deposits in New South Wales were worked during the war years of 1941-44 during the shipping emergency and produced 1,355,417 tons, compared with an output of approximately 43,000,000 tons from Iron Knob between 1901 and 1949.

Jan 1, 1951

By Lindner E, Bosio M

South Australian coals are all low in rank and generally poor in quality, with difficult combustion characteristics. This circumstance makes the selection of a fuel source for future power generation difficult, requiring careful study and detailed analysis of the various alternatives. Combustion characteristics can have a significant effect on plant design and costs, and need early attention in any exploration and evaluation programme. The physical location of the deposits, often remote from established infrastructure and centres of population, is also a major factor in the ultimate cost of power at the poirl use.

Jan 1, 1977

By Higuchi K

For the mechanisation or automation of mining, recognition of the shape of mined cavities is basic information. A three dimensional shape measuring system, developed and tested, includes an ultrasonic range finder which is attached to the tip of a serial link manipulator. The range finder can be moved to any position and direction in the operational space of the manipulator. The position of a point on the surface of the object is obtained from the position of the range finder, the direction of the beam of the ultrasonic waves and the measuring distance of the range finder.To avoid collision between the sensor and the object, the manipulator is controlled to trace the surface of the object For the tracing control, another ultrasonic range finder is employed. The test results show that the developed system has high performance.

Jan 1, 1991

By Gillies A. D S, Supriyadi

The landed cost of coal to the international customer is a major parameter which determines market competitiveness. Rail, port and shipping charges represent 30 to 50 per cent of landed costs for Australian mines selling to Asia. This prop

Jan 1, 1994

By D Bradshaw

The recovery of molybdenum at Kennecott Utah Copper (KUC) has become increasingly important as its demand and price have risen dramatically in the last few years. Consequently, the flotation behaviour of the molybdenum bearing mineral, molybdenite, has received a significant amount of attention. The flotation performance of molybdenite generally lags that of the copper sulfide minerals and is much more variable. There are many factors including particle size, liberation, surface slimes and oxidation that contribute to this and also much speculation as to the relative contribution of each of these factors. This paper discusses the morphology of the molybdenite found at KUC, the mineral associations in the different lithogical ores types and the effect that each of these has on flotation performance. Quantitative mineralogical analysis and an assessment of particle shapes are used to explain that flotation behaviour does not necessarily follow expected trends and that some behaviour is counter-intuitive. This unique behaviour can be explained by the morphology and anisotropic nature of molybdenite.

Jan 1, 2008

Ranger Uranium Mines (RUM) operates an open cut located in the Top End of the North- ern Territory. Strict environmental controls govern all operations and the water management requirements have the greatest impact on mine planning. The two main goals of planning are to provide mill feed and to mine sufficient suitable quality waste rock for ongoing con- struction of the tailings dam. Early planning concentrated on staged development of the pit to provide access to as much ore as possible for a given amount of development. All waste was considered to be suitable construction material. Grade control of crusher feed was the main problem in planning, as wide vari- ations occur in ore grade over relatively short distances. Water management for the site ope- rates a no release' system for contaminated waters. Design storage has proven inadequate, and the open cut has been used as the extra storage. As construction of future stages of the tailings dam requires non-mineralised rock materials which meet specific quality criteria, the mine has had to re-examine long term plan- ning and pit development strategies. This has entailed the collection of much data not re- quired under normal mining conditions, such as the assaying of waste drill core. The overall impact on mine planning of the environmental regulations has been to alter the philosophy of earlier planning, making it necessary to create a new strategy for pit development with

Jan 1, 1984

Over the last 100 years in the Polish mining industry considerable work has been done to assess optimum slurry, develop flexible delivery systems and adjust the fill technology to a wide variety of mining and geological conditions. Sand or industrial mineral waste materials for the backfilling of underground voids are used to control ground movement and surface deformation. This paper discusses various criteria to be considered in the preparation of a fill, including slurry properties, mine infrastructure, mining geometry, placement methods and the purpose of the backfill. This paper presents laboratory and in situ test data on the influence of materials parameters on the slurry flow in a pipeline system, stiffness, permeability, binding time and strength of a backfill, on the distribution of mixture in underground voids or the penetration between roof fall materials.

Jan 1, 1998

By Piotto P

Pit optimisation algorithms are designed to produce a pit with maximum value, but for certain minerals like iron ore, limestone, coal, etc, it is also necessary that the designed pit contains ore which meets the customer's chemical specifications. This paper describes a technique of using linear programming for blending optimisation and the Lerchs-Grossmann algorithm (as in Whittle's 3D software) for pit optimisation in tandem, to achieve pit designs of targeted grade specifications.

Jan 1, 1996

By Coulborn W. T, Glasby G. P, Maylan M. A

Research cruises by HMNZS 'Tui' (1986) and RV 'Moana Wave' (1987) investigated the geology, geophysics and seafloor mineral resources of Manihiki Plateau in the central Pacific Ocean.Manihiki Plateau is a large (500,000 km2) mid-ocean platform that rises 3000 m above the abyssal plains of surrounding ocean basins (depth -5500 m). Its foundation evolved about 112 Ma ago by massive outpouring of basaltic lavas at a plate triple junction. The plateau is blanketed by a 900 m thick sedimentary section comprising (i) mid-Late Cretaceous volcaniclastic sandstones / siltstones grading upwards to limestones / chalks and (ii) -500 m of Tertiary nanno-foram chalks and oozes. Cores from DSDP 317 drill-site on the Manihiki High Plateau indicate that the volcaniclastic sediments contain native copper and some thin beds rich in organic carbon.

Jan 1, 1990

By J J. Jiang, M Reimnitz

The Kalgoorlie Consolidated Gold Mines (KCGM) Fimiston Open Pit is mining through a dense network of disused level workings and open stopes of greatly varying sizes. The condition of the stope crowns and remnants is often unknown, and ultimately these structures become a significant proportion of the production floor and pit walls. Significant seismic events and occasionally rock bursts often occur in the underground workings. Seismicity is becoming an issue to the viability of the KCGM Fimiston operations. KCGM needs to take a leading role in understanding mine-induced and regional seismicity. The seismic system trials were initiated in the Fimiston Open Pit in 1996 using the ISS system. The initial system included two triaxial geophone arrays and two triaxial accelerometer arrays installed into two boreholes. The main objectives of the trial were to investigate the suitability of the two types of sensors and the detectability of seismicity in the pit. The trial was regarded as a success and the system has been expanded and improved. The current system consists of 12 triaxial geophone and accelerometer arrays and nine uniaxial geophones. The 12 triaxial arrays are installed in nine boreholes drilled from the pit and the nine uniaxial geophones are installed from underground level workings about 660 m below the original surface elevation. The system is designed to provide seismicity coverage for the entire pit area that is about 2.7 kilometres long, 1.5 kilometres wide and about 300 metres deep. The accuracy of the source location has always been a challenge due to the existence of the dense concentration of stopes and lack of the sensors. It is uncommon to have direct ray path for the seismic waves to propagate to the sensors across the strike, hence sensors have been located along strike and under the old workings. This paper discusses some of the challenges associated with seismic monitoring near mine remnants and seismically active faults. The results of the seismic monitoring are presented, and contrasted to results of three dimensional boundary element numerical modelling. The impact of the seismicity upon pit slope stability is briefly discussed.

Jan 1, 2003

Carbothermal Reduction and Nitridation of Ilmenite Concentrates and Chlorination of the Reduced Samples

Sep 13, 2010

By T Ueda an, T Sasaoka, A Yabuki, H Shimada

The basic concept of auger mining is to extract coal beyond the economic limits of surface mining technology by drilling holes of an appropriate diameter size into the exposed seam of the highwall as deep as is technically, economically and operationally feasible. This method of mining is used at the final highwall of typical surface mining operations. This paper describes the auger mining systems and discusses the methods to increase the coal recovery in auger mining from a field trial in Australia.

Jan 1, 2003

By Glastonbury J. R

The kinetics of the direct chlorination of, zircon in the presence of carbon was studied at temperatures between 9000C and 12000 C. From the experimental data it is prop- osed that the most likely mechanism for metal oxide (MeO2) chlorination is as follows: At I Surfaceon zMeO2+ZMeCl - MeOC12 (1) At Carbon MeOC12+C+Cl MeC14+CO (2) Surface It.is envisaged that this type of mechan- ism would occur for both the zirconium and, silicon. constituents of the ore. In the above mechanism; the surface re- actions appear to be fast and not rate controll- ing. In a carbon surface deficient bed the diff- usion of oxychloride intermediate through the boundary layer to the carbon surface becomes the rate controlling step. In a zircon surface deficient bed the diffusion of oxychloride away from the zircon surface controls the reaction. This postulated mechanism can be used to ex-, plain the observed experimental effects.

Jan 1, 1973

By E Yurakov, D J. Ashelford, M I. Slate

The push for increasing coal production rates continues to place increasing demands on mine management to safely and effectively control seam gas. Gas drainage strategies applied vary in both effectiveness and form. Methods employed are a function of assessed risk, gas reservoir characteristics, surface and underground access, budgetary constraints and gas utilisation potential. With the aim of establishing and optimising the effectiveness and efficiency of gas drainage systems, Australian coal miners in cooperation with gas management specialists are embracing the use of gas reservoir simulators and gas emission models. This paper discusses the evolution of gas drainage practices in Australian underground coal mines and the role of gas reservoir assessment methods in optimising gas drainage systems and gas production forecasts.

Jan 1, 2005

By D La Rosa, A Jankovi, A Dance, W Valery

This paper presents the methodology for optimising blasting and comminution processes in terms of fragmentation developed by Metso Minerals Process Technology Asia-Pacific and South America (MMPT). The methodology is called process integration and optimisation (PIO) and involves a number of steps: benchmarking, rock characterisation, measurements, modelling/simulation of blasting and comminution processes and where required, material tracking. The measurements collected while at site are combined with rock characterisation and definition of ore domains to model the complete process chain. These data are used to develop site-specific models of blast fragmentation, crushing, grinding and flotation. This allows customised blast patterns to be developed that optimise both crushing and grinding performance. For each domain, blast designs are recommended to generate the optimal fragmentation size for downstream processes. The objective is to minimise the overall cost for the entire process and the changes often have a positive impact on the mining operation. Process constraints such as wall stability, ore dilution, muck pile characteristics, size of mining equipment, size and installed power of crushing and milling equipment and other process bottlenecks are considered in the blast designs. This methodology has allowed many operations around the world to significantly increase their production: generating typically five to 20 per cent higher concentrator throughput. A number of case studies will be discussed in this paper to describe the structured approach taken and demonstrate the benefits that are achievable. This paper will focus on the role of blasting in the optimisation of the entire mine to mill process chain and discuss elements of the PIO methodology: rock characterisation, fragmentation modelling and measurement, the relationship between fragmentation and mill throughput and material tracking.

Jan 1, 2007