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By D Pastars, J L. Mauk

Located at the southern end of the Awhitu Peninsula, the Waikato North Head ironsand mine is approximately 50 km southwest of Auckland . The ironsand deposit consists of Quaternary sands, clays and peats, formed by aeolian and marine processes. We sampled on widely- and closely-spaced intervals to test variability within the mining area. X-Ray powder diffraction shows that samples contain feldspars, quartz, pyroxenes, amphiboles, clays and titanomagnetite. Densities range from 1.6 to 2.5 grams/cubic centimetre, with porosities from 30 to 43 percent. The percentage of magnetic minerals values range from 0 to 75 percent, slimes (clay minerals) values of 0 to 26 percent and non-magnetic minerals from 20 to 95 percent. Mineralogical differences in the Mitiwai Formation and Waiuku Blacksand Member cause bimodal populations in the density, magnetic minerals, nonmagnetic minerals and slimes plots. The Mitiwai Formation has higher non-magnetic mineral values and lower density, slimes and magnetic mineral values than the Waiuku Blacksand Member.

Jan 1, 2001

Blasthole cone samples are used for grade control in most of the iron ore mines of the Pilbara of Western Australia. This method of sampling is straightforward when the target sampling interval matches the mining bench height but is problematic when the blasted bench is 'flitch' mined in two or more passes. Crucially, the sampler needs to decide which part of the blast cone represents the upper and lower flitches to be mined. This sampling selection decision is usually made by assuming a certain proportion represents the subdrill component of a sampling face in a blasthole cone and the two flitches are split equally from the remaining portion. In this study of a West Australian channel iron deposit, sampling experiments were carried out to determine the actual proportions of a sampling face in a blasthole cone by spray painting the blast cones at flitch and subdrill boundaries during the drilling process. Measurements were then taken to assess the differences between assumed sampling face proportions and actual proportions. A set of paired samples was also collected from a number of blastholes with one set using the assumed proportions of each flitch for each sample, while the other set sampled the actual proportions, which were identified from the cone painting process.

Mar 1, 2010

Magnetic anomalies in the Southern Coalfields have been subdivided into two characteristic types. Each type is attributed to a separate cause, one being basement structure, and the other near-surface igneous intrusions.Detailed geological mapping of the area and the ability to sample throughout the coalmines greatly assisted in this subdivision.The Triassic sequence contributes no magnetic effect of its own except to diminish the effect of sources within the underlying formations by raising the level of observation.Detecting the presence of igneous intrusions ahead of colliery working faces by magnetic observations within the coal mines may be of value in preventing accidents caused by gas outbursts and in planning the workings so as to avoid loss of production time.

Jan 1, 1967

By B Mead, N D. Pascoe

The Grasberg block cave rail haulage system will be located in the Grasberg mining district on the island of Papua, Indonesia at an elevation of almost 3000 m above sea level. It will transport 160 000 t of ore per day from multiple chute galleries to the underground crushing systems. The design entails approximately 23 km of rail (ballasted and embedded track), over 120 ore chutes to deliver ore to the muck cars and three unloading stations to deliver ore to the crushers. The rail haulage system is a closed-loop system entirely within the underground mining complex.The GBC rail haulage project will be a substantial operation. Trains consist of 11–12 bottom-dump 20 m3 muck cars driven by a 40 t electric locomotive, about 400 t per trainload. Approximately 12 trains and one spare are required to maintain full production at 160 000 t/d. All rail installations will be 1435 mm (standard) gauge with AS60 steel.The rail system is designed to operate in full automated mode, including chute loading, hauling and dumping. The operation will be controlled from a surface control room.The rail haulage project has been divided into five stages, which will be brought online over the course of ten years. Current development and construction are focused on Stage 1 for initial production that will occur beginning in late 2017. This stage includes 24 chutes in three chute galleries, one unloading station, workshop areas and almost 7 km of track (3 km of embedded and 4 km of ballast).This paper describes the key components of the rail haulage system and reports on the current status of development and construction of the system. This paper also overviews the challenges, successes, issues and risks of this project in areas such as scheduling, development, construction and operation.CITATION:Pascoe, N D, Mead, B and Vega, H, 2016. Grasberg block cave haulage project – design and construction update, in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016), pp 585–598 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016

By A L. Withy

This paper is intended as a review from a planner's viewpoint, of the relationship between town and country planning, a primarily government activity, and the minerals industry, which, with the exception of coal, is a largely private enterprise activity. The paper first considers the nature of the system of planning in New Zealand, and the objectives sought by planners in relation to minerals are discussed. The reasons why these objectives are not generally being achieved are investigated. A final section deals with the gap between objectives and achievement, and suggests a number of ways in which this gap may be narrowed.

Jan 1, 1976

Minerals processing needs a step change in energy efficiency. While the search for new technology breakthroughs is important, huge gains are still available by better using existing research outcomes. This potential remains untapped due to a combination of organisational 'silos', inappropriate performance measurement, and poor science in some areas. It is time to see the elephant in the mill.

Sep 13, 2010

Disasters are often tragic outcomes of high-risk technologies such as mines. In Australia, more mines are being developed every day, and the risk of disasters is ever increasing. No matter how effective our conventional safety devices are, there is a form of accident that is inevitable. These relate to accidents that result from æinteracting failuresÆ in a way that could not be foreseen by the designers. In so-called ætightly coupled production systemsÆ (processes that happen very fast, such as on a high producing mine) the risk is even higher and our risk controls mostly introduce some sort of a technological fix. While we are at the one hand attempting to control the risk, we are also introducing another level of complexity. Are we really controlling the risk? This is one of the fundamental questions that will be addressed in this paper: Do we have the ability within the mining industry and other industries to effectively prevent these catastrophes, or are we, on the contrary, faced with an increasing risk as a result of increasing complexities of our technology, management systems and practices. This paper will contend that perceived improvement in risk control is an illusion of activity, and that the likelihood of mining catastrophes may be exponentially increasing. Although the paper focuses on the mining sector many aspects may be applicable across a range of industries. This paper will further contend that we are applying the right solutions to the wrong problems. Our focus is technological and procedural, while our problem is one of production cultures ripe for error and failure.

Jan 1, 1999

Study on Basic Theory of the Grain Settlement in Fluidised Bed This paper takes thick goal grains (less than 1.5 cm) as research object. According to different densities and particle sizes, thick goal grains are divided into 20 kinds of narrow density and narrow size level average grains. Free settling and hindered settling tests are respectively carried out in ?100 fluidised bed thick goal separators. Hindered settlement includes hindered settling velocity test and measurements of suspension density. Results show follows. (1) Fluid state in separator belongs to transition region. Alien's law is the appropriate formula of thick coal particles free settlement terminal velocity. (2) The main factors affecting hindered settling velocity are the number of solid particles in medium and the structure feature of the particle group. The bigger volume fractions of solids ? is, the smaller decreasing velocity coefficient of particle hindered settlement ¯ becomes. In the organism from bottom to top, density of suspended particles in fluidised bed gradually decreases, but near the top of the suspended particles, the density increased slightly. With increase of density and size, suspension density reducing extent increases from bottom to top of separators.

Sep 13, 2010

By Shepherd J

Megascopic and microscopic studies of cleats and mining induced cleavage in Ihe first workings at Leichhardt Colliery reveal the presence of four distinct fracture sets. Microscopic studies confirm underground observations of the fracture sets.The most likely order of formation of the fractures is (i) "butt" cleats (ii) facc cleats (iii) shallow dipping faults (iv) mining induced cleavage. Three fracture sets apparently formed by tensiIe failure. Microscopy shows that the mining induced cleavage surfaces have preferred starting or lerminating points at the extremity of a "butt" cleat and a vitrite-dull coal band boundary. It is postulated that the induced cleavage begins at 'butt' cleats which behave as Griffith flaws under high compression around Leichhardt Colliery faces. Instantaneous outbursts of coal and gas are associated with only those workings which are affected by mining induced cleavage and occur at or adjacent to working faces.

Jan 1, 1981

The mineral industry is an important element in the human environment and in varying degrees contributes to the general standard of living throughout most of the world, both by supplying the basic materials required for heavy industry, transportation, construction, scientific equipment, and many labour saving tools and also by its contribution to the international economy.When projecting population growth and per capita resource utilization against a finite amount of nonrenewable mineral resources, it is apparent that at some future time, if the established trend continues, the supply of industrial minerals will progressively become exhausted according to their relative scarcity and world demand.In one way or another all of nature's mineral resources are used in the sel'vice of man. Some of the products of their manufacture are essential to the survival and further development of our civilization, others are luxuries, desirable but not essential. Marine vessels are essential to maintain a flow of resollrces around the world, and as trade increases the size of the fleet will grow and the quantities of metals needed will be greater.The commodities they transport, may be used in an inefficient or extravagant manner causing unnecessary depletion which may adversely affect the activities of future generations. An example that comes readily to mind is fuel oil, the international transport of which uses a vast tanker fleet. When refined, large quantities of motor spirit are used in motor vehicles. The U.S.A. alone uses 70 billion gallons annually in the 90,000,000 automobiles in use.Much of this is used in private cars-of which there is one for every 2'3 people-for transport between home and city. Well organized community transport would serve the same purpose, conserve a scarce commodity, take some of the stress out of livingdriving in a major city can hardly be considered a relaxing experience-and minimize the problem of atmospheric pollution.Whilst man has demonstrated his great versatility...

Jan 1, 1973

A review is presented of developments in mill liners to improve performance in terms of wear, impact, as well as mill grind and throughput. These developments are in response to the growth in size of SAG mills and the use of larger ball loadings and ball sizes in modern SAG milling practice. Shell liner developments include specific mechanical design features such as special bolting, directed metal flow to prolong liner life and a focus on the process aspects of the mills to provide more effective grinding motion with reduced wasteful ball-on-liner impacts. Grate design developments aim to provide high throughput of material, especially in the larger size fractions, while providing good impact and wear life. Curved pulp lifters are designed to ensure, at high mill speeds, complete discharge of coarse solids from the mill.

Jan 1, 1999

By F K. Buckley

Currently, Kanieri Gold Dredging Limited operates the only large scale gold dredging operation in New Zealand. It dredges a claim in the Taramakau River using the bucket dredge 'Kanieri'. This dredge, a 'Yuba' type, was designed and built in the 1930s. On the current claim it works about 12 hectares of ground a year. Because of its design, the tailings from the 'Kanieri' make land restoration difficult. This was unimportant until it commenced its new claim ML-32-310 in 1978. The conditions, attached to this licence required it to restore the land for afforestation, the designated use fur the Crown land being mined. With the company planning to work future claims on the Grey River, it decided to undertake restoration work on the Taramakau to demonstrate its capability of establishing pasture land on tailings, a more difficult task than restoring the land for afforestation. After two years and the restoration of two blocks totalling 22 hectares, reasonable pasture establishment has been achieved. Much has been learned to date and further refinement of the techniques used will take place over the next two years. The quality of the tailings produced has improved as a result of the limited modifications possible on the existing dredge. This has been significant in achieving better results. The knowledge gained will be taken into account in future dredge design. Both the Company and its Consultant are confident of achieving satisfactory restoration of dredge tailings for pasture land.

Jan 1, 1981

By J Euston

In the 1990s round flotation tanks were introduced as a result of the lower fabrication costs for larger cells. It was soon observed that round tanks held a number of further advantages over the traditional rectangular cells, such as better hydrodynamics, lower costs and reduced footprint per unit volume.In the last twenty years flotation cell sizes have increased almost exponentially and designs of 250 to 300m3 are a well established standard with plans for full scale pilot installations of 500m3. The option to install these large cells gives flexibility in circuit arrangements and allows efficient and economic matching of flotation lines with modern mill designs. The benefits of scale up are well known with reduced numbers of cells required, lower power costs per unit volume, etc. These benefits will be briefly reviewed with specific reference to the installation of 300m3 to 350m3 flotation cells at the Copperton Concentrator of Kennecott Copper in Utah, USA.The sophisticated techniques required to model these ‘supercells’ have led to a critical review of the fundamentals of flotation science and engineering. In addition to outlining the advantages of large flotation cells, this paper will review the science which supports, and occasionally challenges, the ongoing trend to larger flotation cells.

Aug 8, 2011

Mr. President, Ladies and Gentlemen, it gives me great pleasure to welcome you, on behalf of the Council and Administration, to this University and extend to you our very best wishes for a most successful and stimulating symposium. We as a College of the University of N.S.W. were always proud of the excellent support we received from your Institute members and the close association that existed between our organisations. Now we have matured into the University of Wollongong and have to stand on our own feet, we will need all the support we can get from such bodies as yours to ensure that we are not only producing graduates but are also playing a vital role in the community. Although there is no planning for a school of Mining Engineering in the near future, we do look forward to this being a viable proposition eventually and we will then be able to offer to your Institute wider facilities for your activities and ones which will embrace both the Mining and Metallurgy phases. Thank you Mr. President.

Jan 1, 1975

(Published by courtesy of the Great Boulder Pty. Gold Mines, Limited)1. INTRODUCTIONThe faults described in the following paper are of a somewhat unusual character, and have presented a serious problem both in the development and mining of many ore-bodies on the Eastern side of the Boulder Belt. They are mentioned only briefly in the literature of the field, but were observed by, both Stillwell (1)t and Gustafson (2), and have been studied by other geologists and operators in various parts of the "Belt." Their effect on the lodes of Hamilton Section, Great Boulder Mine, was described by King (3) in 1937, and, during recent years, they have been encountered in most of the Great Boulder workings extending east of the Boulder Dyke.Although this paper is based mainly on a study of faulting and development problems on the Great Boulder mine, the general conclusions reached may be applicable to the solution of similar faulting problems in other mines throughout the field.In order to arrive at a clear understanding of the somewhat complicated relationships which the east-dipping faults bear to the lode systems it will be necessary to give a brief outline of the salient geological and structural features of the "Belt" before proceeding to describe the faults themselves.2. GENERAL GEOLOGYThe most recent descriptions of the geology of Kalgoorlie are those by Stillwell (1) and Gustafson (2) and the reader is referred to these as representing the basis of current knowledge of the geology of the field.The Boulder Belt is comprised of a central core of altered quartz dolerite which is flanked on either side by fine grained greenstones and lavas, usually referred to as the calc schists. Down the centre of the quartz dolerite mass there is an infolded bed of slate (2, p. 105) which has been intruded in lit par lit fashion by albite porphyry; the composite body of slate and porphyry so formed is known as the "Boulder Dyke." Numerous smaller porphyry dykes intrude both the quartz dolerite and the calc schist; these vary in composition and range from chloritised hornblende porphyrites to albite porphyries.The whole of the rock assemblage has been subjected tG a considerable amount of folding, faulting, shearing and fracturing, the greater part of which took place before the formation of the lodes.

Jan 1, 1941

By Worner H. K

Education has always been a topic to rouse the interest of mining and metallurgical engineers, but the recent activities of the Education Committee of the Australasian Institute of Mining and Metallurgy 1, 2, together with the moves throughout the Commonwealth to extend the field of technological education, have made the subject a very live one at the present time. The authors have felt it would be appropriate that on the occasion of the First Ordinary Meeting for 1950, in Victoria, some contribution should be forthcoming concerning the history, present status and possible future trends of mining and metallurgical education in this State. As for the past, the time approaches when there will be none having personal recollections of the beginning of Victorian mining schools or of the men who started them. As for the future, it is obvious that rapidly expanding metal-producing and metalconsuming industries will demand a greater output of competent graduates and diplomates. The era immediately ahead seems to be bristling with opportunities, but mining educators need to temper their enthusiasm for various policies and programmes with the realisation that they are helping to train men who will be leaders 15-20 years hence when the problems of industry and trials of life generally may be very different from what they are to-day.

Jan 1, 1950

Common brattice cloths in use in Australian coal mines are compared by permeability measurements. The respective advantages of twill weave and tarpauling* weave cloths are listed, and the improvements to be obtained in the ventilation of a mine by using tarpauling cloths instead of the commonly used twill cloths are stressed. Plastic cloths are widely used overseas and are briefly discussed.INTRODUCTIONThe onset of extensive full-scale mechanization in Australian coal mines during the past few years has increased attention given to the ventilation of working places. Many inadequacies of the present system have been brought to light and not the least of these is connected with the use of brattice cloth, both in directing the flow of air around the face and in acting as a temporary sealing mechanism. A well-constructed line of brattice will only provide fair ventilation for a distance of 100 ft. Beyond this point the volume or air reaching the face falls off rapidly.Some of the shortcomings associated' with the use of brattice cloths are:1. Hurried installation, necessitated by a rapid advance, often results in poor workmanship with, consequently, an excessively high leakage rate.2. High places caused by falls of roof are difficult and time-consuming to seal.3. Curtains, in lines of brattice crossing transport routes, are difficult to maintain.4. Lines of brattice interfere with rock-dusting and clean-up of fine coal.5. Repair and maintenance of brattice consumes much...

Jan 1, 1959

The mineralogy and textures of a portion oC ore from the 25 level northern orebody, North mine, Broken Hill are described. This ore, in places, contains up to 70 per cent cubanite (CuFe2S3 ) which has crystallized directly with other sulphides and associated gangue minerals.Several breakdown reactions involving the cubanite are also considered.

Jan 1, 1969

By D Craw, L Cox, R J. Norris

The Rise and Shine Shear Zone is a mineralised low-angle deformation zone traceable for at least 7 km through biotite zone schist of the Dunstan Range, central Otago. The zone is commonly believed to be similar to the actively mined Macraes deposit. The Rise and Shine Shear Zone occurs in the immediate footwall of the Thomsons Gorge Fault, a regional scale Cretaceous normal fault that juxtaposes chlorite zone schist against biotite zone schist. Most mineralised rocks are deformed and record a progression from early stages of semiductile deformation to more brittle cataclasis. Folds in mineralised rocks trend northwards. The mineralised schist is hydrothermally altered with variable silicification, sericitisation, chloritisation, replacement of titanite by rutile and carbonate alteration. Gold is associated with pyrite and arsenopyrite and occurs in both ductile and brittle microstructures. Sheared and mineralised schist is cut by north-striking fault zones which host mineralised quartz veins. Veins in the shear zone contain hydrothermal albite. Trace element analyses show enrichment in As, U, Th and rare earth elements. Many of the above features are similar to Macraes deposit, but there are important differences. In particular, the Macraes deposit is hosted in lower grade rocks and truncated beneath by a normal fault, Macraes has no U or Th enrichment, Macraes veins have no albite and folds at Macraes trend NW-W. Rise and Shine mineralised rocks have no Cr enrichment and no hydrothermal graphite.

Jan 1, 2005

By V P. Elpatyevskaya, V S. Arzhanova

Main geochemical problems concerning the environment and mining industry interrelation are connected with the transformation of natural water chemistry by mining wastes. The investigation of many mines in Primorye, the southern part of the Russian Far East, showed that their mining waters have high concentrations of heavy metals and aluminium. Water acidity is primarily connected with the amount of acid-forming sulphide minerals in ores and also depends on the neutralising capacity of rocks. Considerable quantity of metals occur in the waters in dissolved form. Metal concentrations in mining waters exceeds the natural levels by two to five orders of magnitude and can't be reduced to the background levels even after multiple dilution. It is necessary to develop and put into practice new technologies so that to reduce the geochemical impact upon the environment.

Jan 1, 1995