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Intensive exploration for iron ore in the banded iron-formations (BIF) of the Pilbara region of Western Australia began in the early sixties and almost immediately established the Hamersley area as a major iron province. The early genetic models for the BIF-hosted ores were based mainly on macroscopic examinations of ores from the "hardcap" zone, and generally accepted a direct relationship with weathering effects on a Mesozoic to Tertiary land surface. Brandt (1964) was the first to suggest a difference in age between the high-grade hematite ores and the more common hematite-goethite types. He initially accepted a supergene origin for both, but later opted for a hydrothermal origin for the hematite ores. Apart from MacLeod (1966), the published views of the next decade reflect a largely parochial interpretation of individual ore bodies, centred mainly on supergene models but with some support for hydrothermal concepts. Except for Ayres (1971), none of the models were backed by detailed mineragraphic data. In 1976, an AMIRA-sponsored CSIRO group began a Province-wide investigation of the wide variety of ore types and BIF, with emphasis on geochemical and textural studies. The resulting conceptual model for a world-wide unified supergene and supergene-metamorphic hypothesis is generally accepted in the Hamersleys.

Jan 1, 1986

By Koh P. T L, Varnas S. R

Fluid flow, heat transfer and combustion in a nickel flash smelter have been investigated by numerical modelling and flow visualisation. The three-dimensional numerical model incorporates turbulent two-phase fluid dynamics, radiative heat transfer and combustion. The main features include the use of the k-E turbulence model, the Lagrangian tracking of particles, radiative heat transfer based on the spherical harmonics method, and chemical reactions. The predicted flow fields are in good agreement with data obtained from a series of flow visualisation experiments on a cold water model. The interaction mechanism between the fluid flow and the solid particles is examined for a range of particle sizes both with and without injected oil in a series of simulations. The heat transfer in the shaft is dominated by combustion and radiation, whereas the ignition of particles is influenced by the particle size and the added oil. Flow and temperature fields for both gas and solid particles are presented as well as the fraction of sulphur removed from the particles.

Jan 1, 1992

By D Obeng, D Alexander

Over the past five years, commodity prices have been high and the focus of many plants has been æthe more metal the better, at whatever costÆ. In the recent economic crisis, the focus has shifted more to reducing the cost of production and operating at higher efficiency. Since 2002, JKTech has partnered with the Century mine in north-west Queensland to transfer technology and understanding through the good, bad and ugly economic environments, using methodology and techniques arising from research at the Julius Kruttschnitt Mineral Research Centre (JKMRC) and other research institutions around the world as part of the AMIRA International P9 Project. The JKTech studies were concentrated around the primary zinc circuit. During this period, Century expanded the primary zinc regrind capacity, installed additional scavenging capacity, installed and commissioned a Jameson cell for concentrate cleaning in the carbon preflotation circuit, and installed additional primary grinding capacity. Flotation circuit models were developed for each of the survey campaigns and enabled opportunities for further improvement to be identified, implemented and tested in the subsequent campaign.

Jan 1, 2009

By Parkes DB

The excavation of sandstone of generally medium strength for the Liverpool Link Line by Dosco Mark 2A Roadheaders has demonstrated the versatility and good performance of road- headers in suitable rock formations. A description is given of the strata traversed by the tunnels together with descriptions of equipment and crews, excavation sequences, operating difficulties and the results achiev- ed. In addition tunnel construction is des- cribed for a difficult section where there was only O.Sm clearance between invert and a four lane vehicular tunnel below, and O.5m clearance between tunnel crown and a century old sewer above.

Jan 1, 1976

By Orrock G, McKee DJ

Mathematical models of autogenous and semi-autogenous grinding mills have now reached a stage of development where they can be usefully applied to practical problems. In particular, the models are suitable for inclusion in simulations of grinding circuits to study the effects of cir- cuit changes, variations in ore type and changes in throughput. The paper describes a simulation study of the Elura grinding circuit where the empha- sis was on investigating methods of reducing product size from an autogenous mill-ball mill grinding circuit.

Jan 1, 1988

By F D Durao, Muge F. H, Rogado J. Q

In the scope of the project named CAPUME II (EEC BRITE/EURAM contract - project MA2M-CT90,-0042(SMA)) for the development of an integrated mine planning system for underground mines, two of the main tasks were the development of a short-term mining planning procedure (module) and a numerical simulator of the mineral processing plant of Pirites Alentejanas - PA. The short-term mining planning module defines the mining sequences by solving a constrained minimisation problem. The ore grade variability is the objective function subject to the geometrical constraints of the mining method and to the maximum of `internal blending'. The optimisation problem is solved by applying a dynamic programming algorithm. The plant simulator is an essential tool of the planning system allowing the preview of metal grades/recoveries of copper, lead and zinc of concentrates streams, given the corresponding metal assays of the run-of-mine ore, defined by the short-term mine planning module. This way, the management can plan the short-term mining operations (the weekly sequence of exploration blocks and the internal planning) in order to fulfill given required conditions, based on a shipment schedule and on a purchaser's formula. In this paper, after a short description of the short-term mining planning module and of the simulation package named SIMUL, a synthesis of the main model development steps and the results of some simulation runs are presented and discussed.

Jan 1, 1995

Reservoir Engineering has developed into an art. One phase of this art is forecasting the futi. perf ormance of oil and gas reservoirs for property valuations. A discussion of the necessity for oil property valuation isgiven. A brief 'discussion of the four most common methods is included and the engineering method is explained in more detail. As an example of oil property valuations, a producing oil lease in Shackelford County, Texas, USA is evaluated.' The recommendations and conclusions arrived at frun the results obtained are presented.

Jan 1, 1962

By Moon N. T, Torrance A. C

This study has considered the effect of mechanical shock on the resilience of the glass microspheres commonly used to sensitize an explosive emulsion. The damage to the glass microspheres caused by detonating cord, emulsion manufacture and the manufacture of the glass microspheres were considered along with the effect of sensitizer concentration on explosive performance. Reductions of up to 50% in the glass microsphere concentration of an emulsion explosive can result from poor initiation practice, such as the use of high strength detonating cord as downlines during initiation. Laboratory results suggest that detonating cords of strength greater than 3.5 g/metre should not be used as this can seriously affect explosive performance, particularly in small diameter charges. This reduced performance results from damage to the sensitizer elements and recrystallization of part of the emulsion phase.

Jan 1, 1990

By Scott SD

The 1986 PACLARK Expedition established that propagation of a seafloor spreading zone into continental crust has created a complex series of volcanic basins on the floor of the Western Woodlark Basin. In addition to abyssal basalts, felsic volcanic rocks were recovered - especially at the leading edge in the extreme west. A recent deposit of hydrothermal Fe-Mn oxides was discovered on an axial seamount of basaltic andesite, and seawater plume anomalies suggest current hydrothermal venting elsewhere. As a modern analogue for the settings in which ancient volcanogenic massive sulfide orebodies probably formed, the Western Woodlark Basin warrants further investigation.

Jan 1, 1987

By Corbett GJ, Leach TM

ABSTRAC'T' Although hosted within an Ordovician magmatic arc, the Peak Hill high sulphidation system displays features typical of younger Pacific Rim high sulphidation epithermal gold deposits. Regional NW trending transfer structures are inferred to localise the magmatic source at their intersection of the NS trending arc. Fluids have migrated from the magmatic source along NW structures and thence exploited permeable horizons, which have become silicified. Alteration displays typical zonation from silicification through assemblages characterised by alunite, pyrophyllite and kaolinite and is followed by breccia/fracture controlled sulphide and gold deposition. Sinistral rotation on the NS arc has dilated NW trending fractures to produce the WNW to EW dilational fractures which host the higher grade ore. Mineral assemblages are typical of formation distal to the magmatic source in an epithermal environment. The combination of alteration and mineralisation zonation with structure provide fluid vectors which target a magmatic source to the SE of Peak Hill.

Jan 1, 1995

By Zenari L, Kent D

As our mines introduce more sophisticated production technology into their operations, the dependence on communication systems is markedly increased to allow the management of the technology. However the attention given to the communication systems has lagged that given the production equipment - namely LHDs, trucks and jumbos. At times it was treated as after thought. However, this is changing as the degree of automation increases in our mines. The communication system is now being given much more priority and is genuinely becoming a part of the mine design. The transfer of information around underground, as well as between the surface and underground, is an essential day-to-day activity, with the aim being a smoothly run operation. However the mine environment is far from static, and situations arise - such as breakdowns or other incidents - that require swift analysis of the issue, its cause and its remedy. Also, as communication systems become more sophisticated their use in areas, other than direct data flow, become available. The importance of communication, its development, and new areas being impacted by communication is the subject of this Paper.

Jan 1, 1997

The geology and mineral deposits of the West Pilbara Goldfield are described and comparison is made with the Pilbara Goldfield,, In the West Pilbai'a Goldfield two adjacent environments are represented by a predominantly clastic succession and a predominantly volcanic succession. These two successions are lateral equivalents and lithologically they are similar to the classical successions at Warrdiwdbna and Mosquito Creek. How- ever, no evidence of a significant erosional break has been found. It is suggested that the Archaean rocks of: the Pilbara Block represent a single geosynclinal cycle, which culminated in orogenesis, within which-local disconformities have been developed in various places: and that the sub-Mosquito; Creek unconformity at Eastern Creek may be the most widespread of these disconformities, Widespread evidence of'preconsolidation movement, aid the intrusion of igneous rock into. unconsolidated sediment, suggest that tectonism and igneous activity began at a very early stage, This was localised along lines of fracture in an unidentified basement.,.Moveme.nt was primarily vertical and persisted into the older Proterozoic, The sediments were enriched in metal by vulcanicity, chemical sedimentation, and possibly detrit`1' contribution. Diagenesis and metamorphism caused the remobòliyation of the metallic constituents of igneous and sedimentary, rocks which were then localised-in loci of dislocation-formed both before and after consolidation.,.. . . , . .

Jan 1, 1964

By Jackson D. G

Iron ore mineralisation in the Paraburdoo environs is known to extend almost continuously over a strike length of 55 kilometres. Six formations of the Mount Bruce Supergroup con- tain high grade mineralisation in varying degrees of importance. Ore is currently being mined from the Joffre and Dales Gorge Members of the Brockman Iron Formation, with smaller, less significant amounts, occasionally taken from the lowermost units of the Weeli Wolli Formation and the upper parts of the Mount McRae Shale. Regional mapping has demonstrated the existance locally of a major unconformity at the base of the Wyloo Group sediments out- cropping south of the minesite. The basal con- glomerates at the unconformity are sometimes mineralised at Paraburdoo. A supergene enrich- ment process controlled by structure, strati- graphy and topography is the only one which can satisfactorily explain the disposition and chemistry of the Paraburdoo iron orebodies.

Jan 1, 1979

By R Austerberry, S Green

Highly weathered ground, limited collar options and the need to achieve a desired outcome at the lowest possible cost led to the need to adopt a construction approach that had no established design methodology. The newest ventilation shaft at Mandalay Resources’ Costerfield Operations had to be established to a depth of 30 m through poor ground best described as ‘sticky swelling clay’, some of which was contained within an old backfilled pit.The ability to excavate a traditional presink was not possible due to limited space and the introduction of men into the shaft was to be avoided due to the associated safety risks and corresponding increase in cost. Piling in conjunction with raise boring and remote fibrecrete application was identified as a possible solution that could achieve the desired outcome at an acceptable level of risk.Construction of the piles was challenging and required continual refinement until an acceptable level of productivity could be achieved. Limitations on concrete delivery was taken into consideration to ensure hole stand-up time was acceptable and re-drills were not required. The adoption of a set process from alignment, drilling, concrete placement and testing ensured the desired design was achieved. Mine operators should consider the use of piling as a method of shaft stabilisation for the portion of raise bored shaft that passes through the weathered zone.The importance of quality control and attention to detail through the entire shaft construction process cannot be underestimated as issues such as insufficient geotechnical investigation, pile and pilot hole deviation, concrete and fibrecrete quality, as well as delays in the application of fibrecrete can place the success of the project at risk.This paper outlines key learnings from a client’s perspective with regards to the concept, planning, design, execution and completion of a 3.1 m diameter raise bore shaft through both weathered and highly structured ground at the Augusta Mine.CITATION:Green, S and Austerberry, R, 2014. Piling and raise bore construction – key learnings from a client’s perspective, in Proceedings 12th AusIMM Underground Operators’ Conference 2014 , pp 35–42 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Mar 24, 2014

By Clark I, Stockton N, Warren L

Nickel flotation circuits currently experience difficulties in recovering fine particles of pentlandite less than ten microns. By agglomerating these particles using shear-flocculation it is hoped to improve the recovery of these fine particles. A sample of massive sulphide ore from the Kambalda region was separated using magnetic separation to obtain a high grade pentlandite concentrate (> 90 per cent). This was finely ground to produce a sample with particles of 50 per cent minus 10 um in size. This sample was then shear-flocculated using a variety of reagents, including xanthates, dithiophosphate and mercaptobenzothiazole (MBT). The effects of reagent type and concentration, conditioning time, impeller speed and type, and pulp density were studied. Froth flotation tests were also conducted on the shear flocculated pulps to compare the effects of xanthate and MBT on the recovery of pentlandite.

Jan 1, 1992

A co-operative research project, combining Commonwealth Scientific and Industrial Research Organisation (CSIRO) research scientists findings and company iron ore geologists' expertise, resulted in new concepts about the origins, distribution and complexitie of iron ores and their parent rocks (banded iron-formation or BIF) in the Hamersley Iron Province of Western Australia. Understanding these problems was important to the efficiency of exploration, development and ultimate mining of iron ores. This genetic model, based on a detailed mineralogic background, was modified by Mt Newman geologists to obtain a user oriented classification for practical application in the field.The proposed Pilbara Iron Ore Classification (PIOC) gives iron ore geologists a basis from which to understand, identify and record the various mineralogic and physical characteristics of the many genetically different ore types occurring within and between orebodies in the Pilbara. More definitive quality control over ore products can be achieved based on the detailed understanding of ore types which the PIOC allows, compared to current classifications which deal only with the physical nature of ores. Of equal importance, the classification remains sufficiently simple to enable owners, operators and buyers to achieve a basic appreciation of ore type variations.With little modification, it is believed the classification has applications beyond the Pilbara, to iron ore worldwide.

Jan 1, 1984

Over the last five years Du Pont (Australia) Ltd has developed a commercial range of new generation emulsion based explosives concurrently with the development of new explosives-placement systems. The paper outlines Du Pont's emulsion technology and history of product development from the initial emulsions (Tovex E & EL) to emulsion/ANFO blends (Tovex BE) through to the most recent development of Du Pont's SOL emulsion component. The paper also outlines the development of materials handling systems on site to load waterproof bulk explosives from the original pumper trucks through to the multipurpose agitator bowl blending and pumping units at the heart of Du Pont's SOL emulsion system currently available within Australia. The last section deals with some of the more important features of enhanced agitator bowl truck designs and outlines examples of the complete SOL emulsion system and methods of operations currently practiced at specific mines within the Bowen Basin coalfields.

Jan 1, 1986

By Johnston S

A blending trial was conducted on 60 per cent Perseverance/40 per cent Rockys Reward underground ore at WMC Resources Leinster Nickel Operations to compare the benefits between batching and blending treatment of the two ore sources. Milling, f

Jan 1, 1997

The karst water system in Han-Xing District is charaterised by heterogeneity in karstification and permeability of the limestone aquifer, unsteady flowing of the groundwater along karst runoff zone system, periodic recharge related with the periodic precipitation, and concentrative discharge of the groundwater in the form of karstic spring groups. The basic law is that the quantity of the water is very large during waterflood period and rather small in dry period, which has brought about difficulties and contradictions in mining and water supply. The measure to bring the karst water under control must be based on the principle of comprehensive ways and on the systems engineering method. Macroscopiclly, it is the reasonable countermeasure to retain surface water in the upstream section of the karst water system and to strengthen infiltration in the midstream section and to combine exploitation and utilization of the groundwater with water protection and mine dewatering in the area in which mines are distributed.

Jan 1, 1988

The Shamrock Gold Mine has been brought from exploration to production within three years. Mining of the openpit is scheduled for June 1990 with commissioning in April of the 180 000 TPA carbon-in-pulp mill on old tailings and rock dumps. The development of a small openpit containing 344 000 tonnes at 3.6 g/t Au in a complex sulphide ore has required extensive metallurgical testwork to optimise recovery, and ensure profitability. The project has been undertaken in a changing economic climate, with increasing restrictive legislation. The decision to mine was further complicated by the escalating cost of installing a heap leach operation in South East Queensland. Decreasing costs of consumables, in particular sodium cyanide, and the opportunity to purchase a suitable transportable mill at a reasonable price made the project robustly viable as a CIP operation.

Jan 1, 1990