Search Documents

A review is given of the development of the author's ideas on the relationship of ore occurrence to regional dislocations in the earth's crust, presently identifiable in particular areas as linear discontinuities in patterns of geological and geophysical data. Ideas originating from field observations in Broken Hill were developed in conjunction with three-dimensional kinematic deformation models which were devised to simulate rock structures, and to illustrate their response to assumed linear and planar movements at the scale of mine and regional geology. These led to the study of linear features in the pattern of Broken Hill district geology, and to the observation that the Broken Hill lode occupies a "cross-roads" position at the intersection of regional geological lineaments where they cross through and deflect the host rocks. A genetic association was therefore proposed. The recognition of significant regional lineaments requires special techniques and treatments of field data originally developed for the Broken Hill situation. The subsequent application of the work to the Western Australian shield revealed that known major nickel and gold deposits also occur where the host rocks are crossed by one or more regional lineaments. These lineaments were recognised as part of a continental tectonic pattern of major linear trends with which major ore deposits are associated. The ideas were later used in exploration leading to the discovery of the Olympic Dam deposit at Roxby Downs, South Australia, which is related to regional lineaments.

Jan 1, 1983

By Kagl J, Publlier M, Nekitel S, Arumba J, Rangin C, Mosusu N

Since the advent of plate tectonic modelling, the Ramu-Markham valley has been thought the site of a classical island-arc/conti- nent collision zone. In this interpretation the units south of the Markham Valley are held to be island are / micrcontinental mate- rial accreted to Australia and those north of the valley are thought to represent a separate Finisterre island-arc terrane. Recent remapping by the Geological Survey of Papua New Guinea shows: (1) there is no terrane boundary along the Ramu-Markham valley (2) the Finisterre Volcanics are probably part of either a fore-arc sequence or oceanic plateau obducted onto a microcontinent/ volcanic-arc composite terrane, accreted to the continental Australian plate. A new tectonic model is proposed for northern PNG and involves: (I) Eocene to Late Oligocene subduction below a microcontinent remote from Australia to produce the Sepik are and related intrusives, the Finisterre Volcanics (fore-arc or possible oce- anic plateau), together with the Alife blueschist. (2) obduction of the Sepik arc in Late Oligocene-Early Miocene times over the advancing Australian plate. This resulted in crustal melting, some of the products of which are the Mid- dle to Late Miocene Akuna and Bismarck intrusive complexes of the Maramuni arc. (3) obduction of the Finisterre Volcanics began in Early Pliocene times and continues today. (4) post-Middle Miocene mineralisation is the result of melting after obduction of the Sepik microcontinent.

Jan 1, 1997

By Muldoon T

Water sprays on mining machines are generally put there to reduce dust; however, research by the Bureau of Mines and others has shown that considerable airflows may also be generated by these sprays. This recognition of water spray-gen- erated air movement led to the "Spray-Fan" - a continuous miner auxiliary ventilation system which was shown to reduce methane peaks by a factor of 15. Recent successes and failures of the Spray Fan are reviewed. More recently, the same principles were used in the design of the "Shearer- Clearer" for reducing dust at longwall shearer operators. The original design was successful; however, a new design is now available which is more practical to install and does a much better job of holding the dust against the face downwind of the shearer. The latest research objective is to eliminate the negative impact of spray- generated air turbulence on continuous miner dust control. Most coal faces in the USA are ventilated in the exhaust mode using "line curtain", and the forward airflow on the side of the heading opposite the curtain is inevitably weak. Air turbulence generated by sprays which are incorrectly located and/or operated at excessive pressures can cause roll back - in which the dust cloud at the face is forced unwind against the ventilation and spreads over the miner cnerator. The general approach to reducing "roll back." is reviewed and art anti-roll back water spray system is presented.

Jan 1, 1983

By Stewart R, Manson RA, Haig DW, Perembo RCB, Kruman B

Since the advent of plate tectonic modelling, the Ramu-Markham valley has been thought the site of a classical island-arc/conti- nent collision zone. In this interpretation the units south of the Markham Valley are held to be island are / micrcontinental mate- rial accreted to Australia and those north of the valley are thought to represent a separate Finisterre island-arc terrane. Recent remapping by the Geological Survey of Papua New Guinea shows: (1) there is no terrane boundary along the Ramu-Markham valley (2) the Finisterre Volcanics are probably part of either a fore-arc sequence or oceanic plateau obducted onto a microcontinent/ volcanic-arc composite terrane, accreted to the continental Australian plate. A new tectonic model is proposed for northern PNG and involves: (I) Eocene to Late Oligocene subduction below a microcontinent remote from Australia to produce the Sepik are and related intrusives, the Finisterre Volcanics (fore-arc or possible oce- anic plateau), together with the Alife blueschist. (2) obduction of the Sepik arc in Late Oligocene-Early Miocene times over the advancing Australian plate. This resulted in crustal melting, some of the products of which are the Mid- dle to Late Miocene Akuna and Bismarck intrusive complexes of the Maramuni arc. (3) obduction of the Finisterre Volcanics began in Early Pliocene times and continues today. (4) post-Middle Miocene mineralisation is the result of melting after obduction of the Sepik microcontinent.

Jan 1, 1997

ATTENTION has recently been directed to the subject of dust production and methods of allaying same in the Broken Hill mines, so that the time would seem opportune for the local branch of the Institute to discuss certain features of an important phase of the health question in connection with underground work. Tests conducted in the Broken Hill South mine and at other mines at Broken Hill have shown that the ordinary operatioils of mining, such as boring, blasting, and shovelling, may be accompanied by the production of considerable dust unless water is judiciously used.In South Africa·dust particles under 5 microns size are regarded as dangerous, becailse they are so small as to be invisible to the naked eye, and wm esc'ape the protections set up by nature in the nose and throat, and thus may be inhaled in large quantity. A micron is 1 25000th part of an inch. This paper contains an account of the work done on the Broken Hill South mine chiefly, though some tests were done on other local mines.An acknowledgment is due to Mr. T. A. Reid, of the Broken Hill South mine, who conducted some of the tests herein mentioned, and under whose supervision most dust counts were made. Numerous dust samples have been taken by means of thekonimeter, an instrument designed by Dr. Kotze, the Government mining engineer of the Union of South Africa, and fully described...

Jan 1, 1921

By F R. M Pires, R M. Carvalho

Supergene processes in banded iron formation (BIF) result in important dissolution, material transport and simultaneous disorder of the residual bands. The rock physical properties such as density, porosity and rheology change during the weathering attack. The itabirite, Paleoproterozoic metamorphic BIF from Quadrilßtero Ferrffero (QF) û Brazil, shows several weathered facies. Strong linking between topographic surface, rock density and iron grade occurs within the weathered zones. This linking is due to partial dissolution of silica and carbonate from itabirite and gravitational rotation and break of the remaining blades, generating kink-like slump structures. The original itabirite density, 3.7 t/m3, decrease at the first leaching steps, until 2.7 t/m3, and increase at the end of the leaching process until 3.6 t/m3. Iron grade increases from 38 per cent to 68 per cent and depressions (sinkhole), subsequently filled by Cenozoic basinal sediments, are developed over the enrichment zones. The formation of important supergene iron ore deposits of QF is intimately related to such a process. Several iron deposits at QF, such as Pico do Itabirito, Fßbrica Nova, Casa de Pedra, Tamanduß, -gua Claras, Cappo Xavier, etc., reveal the aspects related to the proposed evolution, implying that the formational process of the soft iron ores had a regional character. Granular medium model helped in the understanding of the development of the structure and the formation of the deposits. A numerical model has been developed in order to simulate a leaching system in a two-dimensional matrix, composed of two types of materials: leachable and unleachable. Equal volume proportion and vertical banding were considered. Drilling data was used as multipoint attractors to remove leachable matrix nodes.

Jan 1, 2002

Since the earliest recorded prospecting of the 1860's mineral exploration and mining in Fiordland has been discouraged by the formidable physical difficulties presented by its isolation, extremely rugged relief, treacherous coastal waters and generally unfavourable weather conditions. Government assistance was often sought by the miners and prospectors but little, if any, support or encouragement was received after the initial period. During the 1840's decorative marble was quarried at Caswell and Dusky Sounds. A prospector discovered and attempted to mine copper sulphides to the north of Dusky Sound (Parks Mineral Beds) and near Mt Solitary. A small Pb, Zn, Cu, Ag, Au bearing quartz reef was discovered and driven on in the granite coast line of Preservation Inlet (Bradshaws Reef) and the ore roasted on site. Alluvial and quartz lode gold was discovered at Preservation Inlet in the 1890's and led to the recorded recovery of 11 000 oz of mainly lode gold. Falloff in grades with depth, thinning and splitting of the reefs and the high mining costs at this location led to a virtual abandonment of the field by 1906. In the late 1950's and early 1960's the geology of Fiordland was mapped by the Geological Survey at 1:250 000 scale, but field work was largely confined to the shore lines of the coast and fiords. In view of the physical difficulties it is not surprising that mineral exploration and mining up to 1970 was limited to the scant attention outlined above.

Jan 1, 1977

By S Szylkarski, D N. Graham

In mining, water management is an operational necessity, requiring planning and detailed engineering, as well as risk assessment. Yet, the hydrology of streams and aquifers typically extends well beyond the boundaries of mine operations and intersect with environmental and social values. Mine managers often plan, design and assess the impact of water management activities (such as dewatering, excess water disposal and flood management) with a mine site or process specific focus. The challenge is that the impacts are spatial, long-term and complex – and may be cumulative across multiple mine sites. Further, there is usually little consideration of the feedbacks and interactions between surface water, groundwater and catchment hydrology. Failure to understand these processes can lead to poor decisions and increased costs. This presentation outlines an approach to simulating integrated hydrology in mining catchments that addresses the shortcomings of traditional modelling techniques.CITATION:Graham, D N and Szylkarski, S, 2016. Simulating integrated hydrology in mining catchments from planning to closure, in Proceedings Life-of-Mine 2016 Conference, pp 101–105 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jun 28, 2016

By P A Ferenczi

The Proterozoic iron oxide related Au-Cu-Bi (Tenant Creek style') deposits at Tennant Creek can be classified as syntectonic polymetallic hydrothermal replacement type mineralisation. These deposits have characteristics in common with a number of other Proterozoic iron oxide (Cu-U-Au-REE) hosted deposits in regions which include Southeast Missouri, USA; the Kiruna district, Sweden; the Great Bear Magmatic Zone, Canada; the Stuart Shelf, South Australia; and the Wemecke Mountains, Canada. Similarities between these and Tennant Creek style deposits include: 1. Tectonic Setting: Formed at shallow crustal levels (

Jan 1, 1994

By Y S. M Tabatabaei, R Hosseini Tabata

Application of Acidithiobacillus ferrooxidans bacteria to flotation of Sarcheshmeh low-grade copper sulfide ore was studied. Sarcheshmeh low-grade ore contains pyrite, which causes some problems in the flotation of copper minerals. In this study, A ferrooxidans was used to change the surface chemistry of pyrite and copper sulfide ores and consequently, their flotation behaviour. In the presence of A ferrooxidans and xanthate as a collector, pyrite was depressed whereas chalcopyrite and other sulfide minerals were unaffected. In addition, the pulp pH remained unchanged. It was shown that the surface chemical properties of the bacteria could be manipulated successfully to achieve the desired effects in a flotation process. The results showed that the recovery of pyrite in the presence of the bio-depressant is 50 per cent lower than when no bacteria were present. At the same time the recovery of chalcopyrite remained unchanged.

Jan 1, 2004

By Nava-Vasquez E, Torres-Torres J, Mendez-Nonell J

The ZA-27 zinc base alloy was poured into cylindrical moulds and solidified under different conditions ie normal freezing and unidirectional freezing. In addition a cylindrical ingot with rheocast material was obtained by stopping the stirring action and, at a specific solid fraction, gravity casting it into a graphite mould. It was observed that the material obtained under normal freezing conditions is likely to present both segregation and inverted pipe. In contrast, the unidirectional solidified and the rheocast cylinders showed the absence of inverted pipe. The segregation pattern was quite irregular in the rheocast ingot while such segregation was more uniform in the unidirectional solidified cylinder. By virtue of these observations, the inverted pipe formation may be ascribed to the interdendritic flow, while the irregular segregation pattern in the rheocast ingot may be attributed to an irregular distribution of the liquid and solid fraction along such a cylinder.

Jan 1, 1993

By G Bournival, Y Pan, S Ata

A custom-made set-up that measures bubble coalescence time and the thin film balance (TFB) technique were used to explore the role of residual xanthate (potassium amyl xanthate, PAX) and salt (NaCl) on the adsorption of two frothers (methyl isobutyl carbinol-MIBC, and di-propylene glycolDPG) at the air-water interface. This paper is primarily focused on the comparison of these two techniques in studying the interaction between the flotation reagents and salt emphasizing their capabilities and limits. The results from the coalescence rig showed that the presence of PAX improved the stability of bubbles in both frother solutions and led to a bubble coalescence inhibition at 50–500 ppm DPG. These measures were compared with the results from the TFB. Findings from the TFB were overall in good agreement with the bubble coalescence time, but a higher stability level was observed in thin films under the same condition. The effect of salt on the frother and PAX mixture was also explored, and the results showed an adverse impact of the salt on the interaction of frother and PAX with both techniques. However, variations were found between them in some cases. The TFB is much more sensitive to the presence of dissolved gas and oil droplets.

Aug 24, 2022

By D Q. Zhu

In this paper, the pretreatment of concentrates by roller press was present to improve the granulation of blends comprising some 30 per cent iron ore concentrates and enhance the sintering performance. It is shown that by pretreatment of fine concentrates through roller press, the content of +3 mm fractions of granulation mixture and sinter mixture permeability are elevated by ten per cent and 35 per cent. In the meantime, a sinter productivity increase from 1.51 - 1.62 t.m-2.h-1 is attainted in pot tests with similar sinter tumble index and at lower coke rate. The mechanism of the pretreatment of concentrates process to improve sintering performance of fine iron ore concentrates was demonstrated by mineralogy that better permeability help form more calcium ferrite and good microstructure of sinter, further proven by the better metallurgical performance of sinter.

Jul 11, 2011

By Yucheng H, Baogui Y, Wenyong L

High-water rapid-solidifying material, called 'high-water material', is a new material developed by the authors over many years. The material can solidify nine times its volume of water into solid. The material is a fine kind of binder with special properties. The solidifying body of high-water material with water has quite a high early strength. The compressive strength of the material within three days can reach the same strength as conventional Portland in 28 days. One ton of the material can replace three tons of conventional Portland cement as binder. Some important achievements have been made in application of high-water material. In metal mines, based on the material, a new full-tailing cemented backfill technology has been developed. The characteristic of the new technology is that high-water material is used as binder and full tailing or alluvial sand is used as backfill aggregate. Because of the application of the new technology, major technical problems in backfill technology such as classifying of tailing, dewatering, transportation of pulp, low strength of hackfill body. environmental contamination and so on, have been solved.

Jan 1, 1998

By Liu Wenyong, Huang Yucheng, Yang Ba

High-water rapid-solidifying material, called æhigh-water materialÆ, is a new material developed by the authors over many years. The material can solidify nine times its volume of water into solid. The material is a fine kind of binder with special properties. The solidifying body of high-water material with water has quite a high early strength. The compressive strength of the material within three days can reach the same strength as conventional Portland in 28 days. One ton of the material can replace three tons of conventional Portland cement as binder. Some important achievements have been made in application of high-water material. In metal mines, based on the material, a new full-tailing cemented backfill technology has been developed. The characteristic of the new technology is that high-water material is used as binder and full tailing or alluvial sand is used as backfill aggregate. Because of the application of the new technology, major technical problems in backfill technology such as classifying of tailing, dewatering, transportation of pulp, low strength of backfill body, environmental contamination and so on, have been solved.

Jan 1, 1998

By M Barden, G Lane, B Quilliam

NQ Minerals PLC, through Hellyer Gold Mines Pty Ltd, plans to reprocess the contents of the Hellyer tailings dam to produce lead/silver concentrate, zinc concentrate and pyrite concentrate (containing Au and Ag). This paper discusses the project development, mineralogy, metallurgy and chemistry of processing Hellyer tailings and the associated environmental benefits. The Hellyer and Fossey orebodies were volcanic hosted polymetallic massive sulphide deposits located within the Mount Read volcanic arc of western Tasmania. Mineralisation was hosted in massive sulphide (pyrite) and comprised predominantly of sphalerite, with lesser galena, chalcopyrite and arsenopyrite. The Hellyer orebody was mineralogically complex (fine grained) and was treated through differential flotation with initially modest recoveries. Fossey ore processing characteristics were similar to those of Que River ore and simpler than Hellyer but treatment still resulted in significant grades in flotation tailings. CITATION: Lane, G, Barden, M and Quilliam, B, 2018. Hellyer tailings – complex mineralogy but higher grade than many ore bodies, in Proceedings Complex Orebodies Conference 2018, pp 35–38 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 21, 2018

By P G. Bourke, A Yáñez, G J. Jameson, N M. L Kupka

The kinetics of fine and ultrafine particles in conventional mechanical flotation cells are limited (Feng and Aldrich, 1999; Trahar, 1981; Wang et al, 2016). Accordingly, even limited recoveries with such machines require long residence times. Theoretical investigations into the rate of capture of fine particles by flotation, have indicated that a key parameter is the rate of shear in the fluid surrounding the bubbles and the particles. Achieving fast flotation rates of ultrafines requires a new method of bringing the particles and bubbles into contact, utilising the beneficial properties of highly dissipative flows to break through the water boundary layer. In 2010, a new type of flotation cell known as the Concorde Cell was described, in which bubbles and particles are brought together in a sonic shock wave (Jameson, 2010). Earlier research had shown that when a dispersion of fine bubbles in liquid passed through a converging nozzle at the local speed of sound, the resulting shock wave downstream generates a mass of even finer bubbles in the flow as it passes through the shock wave. The fluid within the shock wave is highly turbulent, and an environment is created that is very favourable to particle-bubble collision and capture. In this paper, we briefly describe the Concorde Flotation Cell and give examples of its use.

Aug 24, 2022

By P Craig, A Crosky, H Ramandi, S Saydam, H Chen

Frequency of reports on premature failure of rock bolts and cable bolts have increased in past two decades. Such a failure threatens both the safety of underground mine workers and the economic viability of the operations. Herein, we report on analysis of rock bolts and cable bolts failed recently in three underground mines in Australia. Magnetic particle inspection (MPI) and scanning electron microscope (SEM) techniques were used to study the failed bolts. MPI showed a number of subcritical cracks on the surface of the bolts. The majority of the cracks in both cable bolts and rock bolts were initiated from the base of ribs (indentation) where the stress concentration was high. SEM examinations showed tearing topography surface (TTS) in all failed rock bolts and cable bolts. These indicated that the failure occurred through hydrogen assisted stress corrosion cracking (HISCC). The results of this study enhanced the understanding about the failure of rock bolts and cable bolts in underground mines. CITATION:Chen, H, Ramandi, H, Craig, P, Crosky, A and Saydam, S, 2018. Analysis of premature failure of rock bolts and cable bolts failed in underground coal mines, in Proceedings The Fourth Australasian Ground Control in Mining Conference (AusRock), pp 407–413 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 30, 2018

By L Abrahamsson

The aim with this paper is to discuss experiences from the ongoing research project ‘Attract: A roadmap to attractive, inclusive, and safe mining workplaces’. The project’s aim is to analyse possibilities, effects, and consequences of the green and digital transformation in the Swedish mining industry from workplace, socio-technical and gender equality perspectives. The research project (2022–2025) at Human Work Science at Luleå University of Technology is financed by the strategic innovation program Swedish Mining Innovation (a joint venture by the national research funds Vinnova, Formas and the Swedish Energy Agency). The project includes a multidisciplinary research group of five senior researchers and five PhDstudents and a broad repertoire of methods, eg literature reviews, qualitative interviews with both managers and workers, workplace observations, workshops, surveys, and project seminars where the researchers and the company representatives together analyse the results. One important part of the project is the applied approach where the researchers work together with two mining companies and one subcontractor company. The project has two parallel main subprojects.

Sep 1, 2024

By Mike Sharwood

This subject is to be discussed in greater depth by Mike Sharwood. It has also been the subject of a mini-symposium by the Melbourne Branch of the AusIMM in October, 1993. The papers from this symposium were distributed to the membership late last year "to raise their consciousness and to promote greater awareness and understanding of the wide range of liabilities that may arise". An introductory paper by Nicholson outlined the many areas in which liability may arise with particular emphasis on expert reports, eg: Takeovers Schemes of arrangement Acquisitions from associates Prospectuses Related party transactions Directors' duties Continuous disclosure Other influences (environmental, occupational health and safety, trade practices)

Jan 1, 1994