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In the introduction to a recent paper dealing with, the relationships of magnetite and hematite in the banded iron formations or "jasper bars" of the Western Australian pre-Cambrian(17)t the author made a brief mention of these interesting rocks, of the principal series in which they occur and of a few of the rock and mineral types to be found within them.He drew attention to the essential shnilarity of these Western Australian banded iron formations to those of the pre-Cambrian of such other countries as the United States Lake Superior region, Sweden, South Russia, India, South Africa and Brazil, and gave a brief summary of his views as to the origin of the formations in Western Australia. Furthermore he stated that the banded iron formations have proved of considerable direct economic importance in the goldfields and other' regions of Western Australia, and he referred to the assistance they have provided the field geologist in geological mapping and the determination of geological structures.It is in elaboration of this last statement that the present paper has been written. In the following pages will be found some examples of the use to which the jasper bars have been put in the determination of the geological structure of critical areas in the goldfields of the State.Firstly, however, it may be as well to recapitulate the features of interest in these rocks. The true jasper bars or banded iron formations including the types jaspilite, banded hematite quartzite and banded magnetite quartzite or chert, together with their higher grade metamorphic derivatives such as banded magnetite-gruneri~ quartzites, magnetitegrunerite schists, fayalite ,and hedenbergite bearing handed magnetitegrunerite quartz rocks and' to 'a lesser extent magnetite-hypersthene grunerite quartz rocks, are abundant in the older series of the Western Australian pre-Cambrian. They are best developed in the older Greenstone or Kalgoorlie series of the goldfields districts, interbedded with metamorphosed basic lavas, tuffs and sediments. The mineralogy andpetrology of these rocks, the history of their metamorphism and their origin have been discusseq elsewhere in some detail by the author(19), (20). In one of the papers(20) it was clearly demonstrated that in the light of the true facts the old silicified shear zone theory of the origin of the jasper bars is quite untenable and that the formations undoubtedly represent sedimentary horizons as was recently pointed out by McKinstry(14).It has also been shown that banded ferruginous cherts, quartzites and cherty carbonate rocks of much lower metamorphic grade are well developed...

Jan 1, 1943

By Maxwell HW

Pacific Coal Pty Limited (a wholly owned subsidiary of CRA Limited) managed the interests of six members of a joint venture formed to mine and export eight million tonnes of export quality steaming coal from a mine developed at Blair Athol in the Bowen Basin of the Central Queensland coal fields. The mine is now operated by Blair Athol Coal Pty Ltd. Crooks Michell Peacock Stewart Pty Limited (CMPS) was awarded a project management and engineering contract for the total mine portion. Following a feasibility study, CMPS carried out an Optimisation Study which produced changes to the design of the project, thus resulting in the project budget being reduced by some A$13 million. In spite of a number of late additions to the scope of work, the project was completed at a final cost of A$148 million, many millions below the reduced project budget. The project was also completed several months ahead of schedule. Total services were provided to take the project from feasibility stage through to the establishment of an operational facility and included project management, planning and control, accounting and financial control, as well as the organisation of engineering, procurement, construction, industrial plant commissioning, and technical training matters.

Jan 1, 1986

A new lead refinery with a. capacity of 230,000 tons per year com-menced operation at*Port'Plsie in October, 1959. This plant' superseded the refinery which had operated from 1933 with the advent of thecontinuous lead refining process. The incorporation of new equipment following local metallurgical developments, together with the overseas demand for lead of extremely low antimony content, created difficulties in operating the original plant. The new refinery project was under-taken to cover this disability and to gain the full advantage of the new processes.Desilverising and softening are carried out in units identical in size to those used previously. Metallic'zinc is now recovered from the entire output of desilverised bullion by vacuum distillation. Final refining is then carried out by batch'treatinent with caustic soda yield-ing lead of purity previously unattainable at Port Pirie.These two processes have replaced continuous dezincing by oxidation, a high temperature process which caused large quantities of lead and antimony to be recirculated. As the final stage is a .batch process the product composition can be.checked before casting. Individual batches can be adjusted to produce special alloys to,consumer's specification.Improved casting equipment has allowed the quantity production of pigs of good physical characteristics either as 56 lb bars or 2000 lb pigs. This, together with the high purity of the lead, has assured the B.H.A.S. position in world markets.Automatic control systems have been extensively employed particularly on the vacuum dezincing unit.The anticipated financial benefits have been achieved mainly by a reduction in the tonnage of recirculated materials, a smaller labour force, and reduced maintenance requirements.

Jan 1, 1963

Acclaimed as one of the most remarkable orebodies anywhere on account of its length and richness, the Oroya Shoot occurs on the eastern side of the Kalgoorlie gold mining district close to the contact of a fine-grained with a coarse-grained greenstone, and in association with sediments. In the same stratigraphic position on the synclinal flanks of a large drag fold there are a number of other flat ore pipes, smaller, but almost as rich in tenor. Although differing in control structure they are believed to be related genetically as all show a characteristic development of a bright-green ore known locally as "green leader". Folding and bedding structures have played an important part in formation of the ore shoots.INTRODUCTIONThe Oroya Shoot is the biggest individual bonanza of Kalgoorlie's Golden Mile. It has been stoped almost continuously over a length of 4,300 ft., and about 2,000,000 oz. of gold have been won from it. Naturally pillars are not left in the best sections of such an orebody and the detailed geology of stoped out portions can only be inferred from examination of adjacent workings.No mention is made in the literature of the actual makeup of the orebody although a few structures are shown on some of the old cross sections. A diagrammatic cross section, Fig. 1, adapted from Stillwell (1929) illustrates the form of the Oroya Shoot.Gustafson (1937) drew attention to the role of folding, previously unrecognized, in Kalgoorlie geology, and indicated that the Oroya Shoot is associated with a minor drag fold on the east limb of the Brownhill Syncline, itself part of a larger left hand drag on the Central Anticline. The latter in turn appears to be part of a regional right hand fold system as shown by Campbell (1953).

Jan 1, 1959

By Girnau G

The necessity of effective dust suppression measures during excavation work is just as uncontroversial in tunnelling as it is in mining. In many respects, in fact, the applied technology is comparable. Notwith- standing, given more careful appraisal, it becomes evident that very different starting conditions exist in both these fields: In mining, there are for instance, well organised firms, which in many cases have been active for several decades, carrying out the required drivage and winning operations - and although there are also experienced firms in tunnelling, these generally speaking form a joint venture in order to accomplish a certain project. These "tunnelling firms" which are formed for a short term, normally only exist for a period of two-to three years. They con- stantly reorganise themselves: from the site supervising engineers by way of the foremen and shift overseers to the gangs working on site. The "firm's headquarters" are also re- located when a new project is started up. Then of course, there is often pronounced fluctua- tion among the crews of a single tunnelling project. Seen from this point of view, a safety expert in tunnelling has a far more difficult task than one in mining. He has not the advantage of knowing every corner of the mine for years if not decades on end, of being familiar with the overall organisation of the enterprise let alone knowing many of the men at the face. This ideal prerequisite for effec- tive decisions pertaining to suitable measures for industrial safety and accident prevention taking all weaknesses into consideration given the interplay of the most varied system com- ponents, can practically only be arrived at in mining.

Jan 1, 1987

By A D. T Goode

Data Metallogenica (DM) is unique as a global mineral sample collection and deposit database with over 70 000 rock samples and a wide range of descriptive, photographic and measurement data. Subscribers have access to approximately four gigabytes of on-line data with many examples included on the public pages. DM commenced its life on the Pacific rim in 1971 and much recent growth has focused on countries of the Pacific margin, particularly Australia, Fiji, Chile, Indonesia and Peru. Approximately 600 separate deposits and mineral occurrences in this region are represented in DM. The sets of rock samples have been photographed at high resolution and included on the web site, together with unpublished descriptions, deposit cross-sections, bibliographies, field and mine photographs, petrology and reflectance mineralogy. Figures and abstracts from PhD theses are a new addition and the donation of proprietary databases by companies and individuals is an encouraging trend. DM increasingly is being viewed as an acceptable and important repository for æfragileÆ and irreplaceable personal and company data, it is also being recognised in its true light as a high level information system, not solely a collection of rock samples. Data Metallogenica is a not-for-profit venture of AMIRA International that requires self-funding from December 2004. Growth and development must be funded entirely out of subscription and sponsorship revenues because no government subsidy is provided. The Pacific rim is in the mainstream of mining and exploration activities worldwide and those involved have much to gain from a dynamically sustaining DM. The home page at www.datametallogenica.com contains much example data and details of subscription and membership rates.

Jan 1, 2004

The kinetics of chlorination of alumina and bauxite with CO/CI2 mixtures were studied in the range 300-1100°C. The temperature of prior calcination is critical in determining the reaction rates. An optimum chlorination temperature in the range 600°C-750°C was demonstrated such that there is no increase in reaction rates with increasing temperature. This lack of rate sensitivity to rising temperature is largely a function of the influence of gaseous diffusion gradients in the porous alumina together with a progressive decrease in surface area.

Jan 1, 1976

By Finlayson J. F

The advantages of rapid and accurate analyses are becoming appreciated in many industries today and have resulted in a great increase in the number of samples received by their laboratories. This has caused some firms to consider the installation of one or more of the instruments available for analytical chemistry. In this country there are relatively few people with experience of instrumental methods and it is difficult for a firm considering the installation of such equipment to assess the advantages which instruments may give them, and to decide which instruments, if any, will be of most use to them. The object of this paper is to give a brief survey of instrumental methods in the field of inorganic analysis. Instrumental methods of analysis have numerous advantages when used correctly. They enable extremely rapid analyses to be made in many cases, e.g., analysis of refined lead by purely chemical means takes about two days whereas spectographically the analysis can be completed in approximately one and a half hours. The accuracy ofinstrumental methods, generally between 1 and 5%, is higher than most chemical methods for small percentages of impurities. Furthermore, if the instrument can be calibrated against absolute standards the errors are usually random and not biased to one side of the correct result. The sensitivity is high, enabling in many cases the detection and determination of smaller percentages than can be detected chemically. This high sensitivity enables and, in some cases, requires the use of very small samples, and results in considerable savings in reagents, allowing the analysis of considerably more samples without undue loss...

Jan 1, 1951

By M, C A. RosiFre, R C. Figueiredo e Silva

Jaspilites and underlying basalt contacts of the Archaean volcano- sedimentary Grpo Parß Group, Carajßs, host giant iron mineralisation in the ~100-km long, E-W trending Carajßs fold. Preliminary, unpublished geochronological data point to a Palaeoproterozoic mineralisation event. Geochemically, jaspilites are typical volcanogenic banded iron formations. Basalts exhibit evidence of spilitic seawater interaction. Iron-associated hydrothermal alteration of mafic rocks was induced by fluid infiltration in amygdales, with development of chlorite- and hematite-dominated zones. In the case of jaspilites, iron mineralisation encompasses: partial replacement of jaspilitic microcrystalline hematite by blasts of martitic magnetite; jasper recrystallisation, producing fine-grained, hematite-free granoblastic quartz; martite recrystallisation, forming lobate¦subhedral hematite; pervasive porosity development by quartz-chert leaching; incipient cavity filling by microlamellar hematite; and advanced filling by coarser, euhedral and comb-textured, tabular- shaped hematite.Peak hydrothermal ore textures indicate typical epithermal-crust conditions, supported by preliminary fluid-inclusion calculations at 160 - 200¦C. Such temperatures and extreme fluid-to-rock ratios during alteration must have exceeded the ambient metamorphic conditions, with the infiltrating fluid relatively hot and capable of leaching SiO2. Therefore, mineralisation developed over exhumed, Archaean, brittly deformed rocks, with mineral associations representative of very low- to low-grade metamorphism. Considering that chlorite (¦talc) abounds in mafic rocks; hydrothermal albite is developed; dolomite fills veins and vugs; the typical rare-earth-element (REE) pattern of jaspilites is significantly modified in higher-grade hard hematite ores (higher LREE); pyrite, copper sulfide minerals and rare gold occur in association with carbonate-quartz-rich alteration zones, it is suggested that an alkaline, H2O-Fe-CO2 mineralising fluid dominated, also containing species like S¦Cu¦Au. Peak-mineralising conditions are likely to have resulted from a single, evolving fluid, via incipient- through advanced-stage alteration phases. The porous, high-grade soft hematite-type ore (SH), rich in microlamellar and anhedral hematite, must have derived from interaction with this relatively hot SiO2-leaching fluid, whereas the high-grade massive hard hematite-type ore (MH) developed due to closer fluid-rock temperature equilibrium conditions, attained by mineral reactions, with relative increase in the Fe/Σcations ratios allowing the precipitation of subhedral-tabular hematite that partially cements the soft-hematite ore. SH and MH hematite ore types must thus reflect intermediate and high fluid:rock ratios, respectively. Since the N5 deposit is to date understood to contain the largest amount of the MH ore, its units are interpreted as the loci of the highest fluid:rock ratios in the district. Preliminary mineralogical information regarding the S11 deposit of the Serra Sul (south range) implies higher-temperature conditions. The near-equant grain size and the granoblastic intergrain relationship, coupled with the presence of riebeckite, augitic pyroxene and garnet, suggest hornfels textures. The data collected, though still relatively sparse, permit the speculation that the immense driving force for the Carajßs world-class iron deposits was a relatively shallow, igneous-related hydrothermal system. If such a model is correct, then the Carajßs Palaeoproterozoic iron deposits could represent an end-member of the iron oxide-copper-gold hydrothermal system in the province.

Jan 1, 2005

By C Pypno, P Nowakowski, T Opasiak, C

Belt conveyors are machines for continuous transport with most applications in mining industry in Poland. This is a result of simple construction and cheap operating costs. But conveying materials by belt conveyors are often in the powder state (eg small coal, gypsum, etc) and during the transport there is a possibility of polluting the environment around conveyor route. A good solution for this problem is the pipe conveyor, where a belt is closed on the route in circular shape and flat on unloading point. Another problem which is indicated in the paper is dusting on the belt conveyor boosters. In Poland a new solution of booster has been designed, whereby dustiness of transportation powder materials is reduced by up to about 90 per cent.

Jan 1, 2003

By A J. Ryan

The Ernest Henry copper-gold Mineral Resource is the major asset heldby Ernest Henry Mining Pty Ltd, comprising A$6.4 billion of containedmetal. The case history presented below describing the evolution andevaluation of this resource generally observes best industry practice and is a good example of effective due diligence in the resource delineation and estimation process. Early reconciliation data from mine production confirms the accuracy and validity of the resource estimate, providing valuable assurance to the mine owners.

Jan 1, 1998

By S Januszewski and, G Dirom, D Christensen

Four field test plots were constructed in 1998 on a sloped waste rock surface at the Myra Falls Operations of Boliden Westmin (Canada) Limited to evaluate hydraulic performance of alternate cover system designs. The field test plot cover systems were designed to control oxygen ingress and water infiltration to the underlying waste rock while providing a medium for a grass and legume vegetation cover. The test plots consisted of a bare waste rock surface (control plot), and three additional plots consisting of native compacted till placed directly on the waste rock surface, overlain by non-compacted till. Two of the test plots included a compacted till layer ameliorated with flyash and bentonite, respectively, to improve moisture retention and reduce permeability. The third test plot consisted of a compacted layer of native till overlain by non-compacted till. A performance monitoring system was installed in each test plot to evaluate net percolation and oxygen ingress to the underlying waste rock. In addition, each test plot has profiles of matric suction, water content, and temperature sensors installed at up-slope and down slope locations. A review of four years of monitoring data shows that the compacted till/bentonite cover system has been most successful in limiting the infiltration of meteoric waters and oxygen ingress to the underlying waste rock material. The compacted till/flyash and compacted till cover systems have produced similar net percolation results and neither have functioned well in maintaining an oxygen ingress layer throughout the year. The amelioration of bentonite with till to produce a compacted barrier layer shows promise in reducing water and oxygen ingress at the MFO site, while the incorporation of flyash with the till did not result in a significant increase in performance. The field performance data clearly demonstrates the need for developing field trials prior to full-scale construction, as opposed to relying solely on an un-calibrated numerical modelling to design the full-scale cover system.

Jan 1, 2003

Australia is presently the world's principal producer of rutile and zircon, and also provides a major share of the world's ilmenite. Since 1980, Australia's share of the world's output of these minerals has fallen. Exhaustion of known resources, together with the changing composition of new deposits, is expected to result in Australia's share of the rutile and zircon output continuing to decline. Its role as a major supplier of upgraded ilmenite, that is synthetic rutile, is expected to increase. In 1994, the Bureau of Resource Sciences assessed Australia's demonstrated resources of mineral sands as follows: rutile 14.4 Mt, ilmenite 132.5 Mt, and zircon 21.0 Mt. These resources are located along the coast of Queensland and New South Wales, in the Murray Basin of New South Wales and Victoria, in the southwest corner of Western Australia, and in the Eneabba region, north of Perth. However, some 45 per cent of rutile and zircon resources along the coast of Queensland and New South Wales are not available for mining because of environmental concerns. World demonstrated resources are estimated at 40 Mt (contained TiO2) for rutile, 50 Mt for zircon and approximately 312 Mt (contained T1O2) for ilmenite. Outside of Australia, the most important resources of rutile, ilmenite and zircon are in South Africa (rutile, zircon , and ilmenite in the form of titania slag), Sierra Leone (rutile), India (ilmenite, zircon and rutile), and Canada (hard rock ilmenite). Significant resources of ilmenite occur in Madagascar and Mozambique.

Jan 1, 1996

There has been a significant increase in exploration and development of mineral wealth in South East Asia over the past five years. This paper describes the foreign investment laws in the region as they relate to the mining industry.

Jan 1, 1993

By B P. Banerjee, S Raval

In the recent past there have been dramatic advancements in the development of remote sensing platforms (satellite, aircraft and unmanned aerial vehicles – UAVs) as well as sensor systems (multispectral, hyperspectral, thermal, light detection and ranging (LiDAR) and radar). However, selection of the appropriate remote sensing technique for a mining application is complex and requires scrutiny on multiple scales including spatial, temporal and imaging capabilities. This presentation highlights various conventional and emerging remote sensing approaches over a mine’s life.CITATION:Banerjee, B P and Raval, S, 2016. Applications of advanced remote sensing systems during a mine life, in Proceedings Life-of-Mine 2016 Conference , pp 116–120 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jun 28, 2016

By J Rola

This paper outlines a laboratory-based design method, founded in critical state soil mechanics, for identification of an appropriate compaction specification to ensure dilative conditions prevail across the design TSF stress range. The method makes use of the critical state line (CSL) and consolidation tests prepared at varying compactive efforts. The CSL and consolidation curves are plotted together in e-log p’ space, with the compaction curves transformed from vertical effective stress to mean effective stress using the coefficient of earth pressure at rest (K0). Consideration is given to the sensitivity of K0 as it is generally not available during the design phase. An example of the design method is illustrated with laboratory data.

Jul 1, 2021

By C R. Sundberg

Despite nearly a half-century of continuous production, the low-grade iron ore (taconite) deposits of North America remain economically competitive sources of raw materials for the domestic steel industry. The continued viability of these mature integrated mining-concentrationagglomeration complexes requires highly efficient utilisation of assets, especially the mineral resource. At Cleveland-CliffsÆ five North American managed operations, enhanced ore characterisation techniques are playing a critical role in their continued success. Due to the low-grade nature and complex mineralogical composition of these deposits, ore characterisation cannot solely rely on assay grades. Historically, taconite ore characterisation has augmented assay grades with bench-scale concentration tests to quantify recoverable mineral. The economic necessity for improvements in mill efficiencies and final product quality has mandated significantly greater knowledge of ore-related impacts. Cliffs Technology Center has met this challenge by developing a variety of novel iron ore characterisation techniques. The applications developed include both in situ and laboratory procedures, plus unconventional data integration methods uniquely suited for these deposits. This paper details the evolution of these novel ore characterisation techniques and their application to each phase of the operation: mining-concentrating-and pelletising. The improved ore characterisation techniques have contributed to successes at individual Cleveland-Cliffs managed operations including mineral recoveries exceeding 95 per cent and productivity increases exceeding ten per cent while consistently achieving customer product quality objectives.

Jan 1, 2002

By Mishra S. N, Mishra R, Sen P. K

Control of silicon in produced through the submerged-arc furnace can result in reduced power and coke consumption in addition to improving the quality of the hot metal. A thermo-chemical analysis of the production of ferro-chromium was carried out to devise strategies to control the recovery of silicon during the manufacture of ferro-chromium. The presence of three thermochemical zones in the furnace with respect to the reduction of silica was recognised from this analysis. Any strategy for the control of silicon recovery has to take cognizance of these thermochemical zones. The effect of various strategies on the silicon level in the hot metal have been evaluated. Possible strategies, such as the reduction of coke level in the charge; the replacement of quartz; pre-reduction of the ore and the control of the temperature profile are discussed in this paper.

Jan 1, 1999

By F Schoenbrunn, T Laros

Deep paste thickeners have been proven capable of consistently producing medium to low slump material for disposal without the need for filters. However, proper design of the entire system is critical for a paste project to be successful. Some of the factors that must be carefully considered in design of a paste system include thickener sizing, tailings impoundment design, underflow pumping, and control system.

Jan 1, 1998

At Yucca Mountain, USA, a tunnel is being built according to nuclear quality standards. It has proved possible to meet very high quality demands while at the same time achieving high advance rates. To be able to do this, routines on how to record and store quality related information have been established. This has meant that a new philosophy has entered the tunnelling industry. Especially for nuclear waste projects, of which Yucca Mountain is one of the first ones to be built, the experiences made and the quality assurance program established will be of great importance for future projects. The paper gives examples of what the Nuclear Quality Assurance system has meant in practice for the tunnelling at Yucca Mountain. And, it also explains why a non-grouted bolt, Super Swellex-, was chosen for long-term reinforcement in the tunnels which might host nuclear waste for thousands of years.

Jan 1, 1999