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In August, 1975, North Broken Hill Limited announced that an intersection of 37.3 m of high grade lead-silver-zinc mineralisation, assaying 26.2 per cent Pb, 495 g/tonne Ag and 21.2 per cent Zn had been obtained at its Mine at Broken Hill, 520 m north-east of its No. 3 Shaft and slightly below the No. 36 level (1581 m). Subsequent drilling confirmed the presence of the extension of the Broken Hill Orebody on the north-western side of the Globe Vauxhall Retrograde Shear Zone and defined 1.8 million tonnes of high grade mineralisation. The area containing this mineralisation was subsequently named the Fitzpatrick Area in tribute to the late Mr. W.E. Fitzpatrick a former Member of the the Board and Manager of the Ccnpany's Broken Hill operations. This paper describes in brief the exploration programme leading up to the discovery, the general geology of the area and the proposed future exploration progranme for further extensions of the orebody within the mining leases of North Broken Hill Limited.

Jan 1, 1983

By J Whittle

This paper describes what is involved in carrying out a comprehensive optimisation of a long-term operating schedule for a mining complex. It details the data that must be assembled and discusses the different approaches to optimisation and what limitations they put on the variables and constraints that can be handled.CITATION:Whittle, J, 2014. Not for the faint-hearted, in Proceedings Orebody Modelling and Strategic Mine Planning Symposium 2014 , pp 3–6 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 24, 2014

By T Ireland

The Rosedale Outfall Project utilised an earth pressure balance (EPB) tunnel boring machine (TBM) for only the second time in Auckland. Although the tunnel was excavated fully through East Coast Bays Formation (ECBF), the downhill gradient along with some unexpected areas of extreme water posed some significant challenges during construction.The Rosedale Waste Water Treatment Plant Outfall Tunnel project was commissioned in response to the growing needs of North Shore City, New Zealand. The outfall tunnel comprises a 3 km long segmentally lined tunnel and a 2.1 km buried marine pipeline, and discharges 2.7 km offshore. The capacity of the new outfall is 6 m3/s compared to the existing outfall capacity of 1 m3/s.Following previous project experience, and with the tunnel located along its full length in the bedrock weak sandstone/siltstone bedrock of the East Coast Bays Formation, tunnelling conditions were expected to be benign. However during construction six high inflow events were encountered, including a full face (3.4 m diameter) of Albany Conglomerate over a 48 m length of tunnel. This material comprised cobbles in an uncemented sand matrix, and inflows were recorded at over 25 L/s.This paper describes the design challenges on the project including the design of a steel fibre reinforced segmental lining for internal pressures. The specification of the machine is discussed including the modifications required to enhance the risk mitigation measures already in place. The ground conditions encountered are discussed and have improved the knowledge of the range of conditions that can be expected in Auckland.Despite the challenges presented during construction, excellent progress rates were achieved and the tunnelling was successfully completed ahead of program.

Mar 8, 2011

Recent work on computerised mineral resource databases at the Institute of Geological and Nuclear Sciences Limited has concentrated on the development of the GERM, REGCHEM, and MINLIT databases, and their integration in a Geographic Information System using MapInfo software on an IBM-compatible microcomputer local area network. GERM (GEological Resource Map) is a mineral deposit inventory with national coverage and more than 10 300 entries. REGCHEM (REGional Exploration GeoCHEMistry) is a database of stream sediment analyses from open-file mining company reports, containing more than 14 000 sample sites from the Coromandel and west Nelson regions. MINLIT (MINeral LITerature bibliography) is an annotated bibliography of literature on topics relating to the exploration and geology of mineral deposits in New Zealand, and includes more than 5000 entries for published books and papers, and unpublished mining company reports, university theses, and government reports. Master sets of GERM and MINLIT continue to be maintained on a VAX mainframe network but REGCHEM is operated only in the PC environment using the Microsoft ACCESS database management system software.

Jan 1, 1993

By Hochwimmer B, Baxter JL

Heavy minerals are mined from two fossil strandlines on the southern Swan Coastal Plain. The Capel shoreline, 7 km inland, and the Yoganup shoreline, 15 km inland are arcuate, northwest-facing, and remote from the modern coast. Based on foraminiferal and molluscan assemblages, the shorelines are probably of Pliocene age. The Yoganup shoreline is adjacent to the Whicher Scarp, which is cut into the Leederville Formation (Lower Cretaceous) at the southern boundary of the Swan Coastal Plain. Stratigraphic relations and detailed sedimentology have been studied from temporary exposures in the Yoganup Extended and Yoganup North mines, within a strandline complex at 27 m and 18-33 m above sea level respectively. Heavy minerals were deposited in thin, shallowing-upward sequences along a wave-dominated clastic shoreline cut into pre-Cainozoic sediments. Lithofacies units deposited in eolian, foreshore, shoreface and lagoonal environments are the most significant sites of heavy mineral accumulation. The data collected provide a basis for further exploration.

Jan 1, 1986

By Verma UK

Mining for sand was active in South Delhi during the last four decades disregarding all norms of safety. The aim of the paper is to highlight what is proposed to be done for mining in Delhi. Apart from the damage to the landscape, the earlier operations gave rise to visual pollution to the scenic Delhi area and there is immediate need of land restoration and landscaping. Future mining should be planned so that the resultant land surface completely merges with the topography and gradually assimilates with the green belt. Restoration of old workings, land reclamation and details of plantation in old pit areas are included. The project also provides a demon- stration site to show the impact of eco-development leading to new legisla- tive measures, as it is in the Capital of India itself and therefore more accessible than any other area. What has been suggested for mining is not the latest and the most modern equipments from the Western point of view but the right equipment to meet the specific requirement of the country. Financial projections are included alongwith technical details of the project to show the benefits to the society. It is concluded that eco-development is essential for the mining in the Twenty- First Century.

Jan 1, 1986

By M K. Singh

Mining is nothing but an art - besides being a science - of extracting valuable minerals from the womb of the mother earth. In this gigantic task, a large number of machinery and equipment are employed judiciously. Wire ropes play a vital role in lifting or hoisting men and materials under hostile/adverse working conditions and constitute a major item of investment on machinery/equipment. The economy of using a wire rope is a concern for engineers, users and the planners. The economic use of wire ropes for mining purposes largely depends on the following factors;Mechanical design considerations - which include tensile strength of wires, elasticity, resistance to abrasion and crushing, fatigue values, static and dynamic loads on wire ropes, factor of safety, fleet angle, etc. Metallurgical consideration - Composition and heat treatment of wire materials, defects like inclusions and voids, surface quality factor, lubrications, micro structural parameters. Operational consideration - Seizing and cutting of rope, storage, care and maintenance, cutting back, etc. Environmental consideration - Temperature and humidity, pit condition, dust, corrosive atmosphere, etc. In the present paper, an attempt will be made to suggest steps for achieving optimum economy while using the wire ropes for extraction of precious minerals and coal keeping in view the points noted earlier. Once technical viability is established, economy is the ultimate consideration for an industry for safe hoisting of men and material.

Jan 1, 2000

By Lorenzen L, Van Der P F

It is the aim of this paper to review recent research in understanding the role of cyanide in the elution of gold. Under conditions of severe pre-treatment (high temperatures and levels of cyanide), the dynamics of elution are determined mainly by the adsorption equilibrium and the flow conditions in the column. When conditions are less favourable for desorption, transport phenomena are rate controlling. The most important sub-processes of elution are the changes in cyanide, potassium and gold concentrations, as well as the change in passivation of the carbon surface. Mathematical models to simulate the various sub-processes are described briefly.The presence of an irreversibly adsorbed species such as AuCN on the carbon is determined mainly by the pH, temperature and the type of carbon. Cyanide in the pre-treatment step will convert the AuCN to reversibly adsorbed Au(CN)2. Competition between cyanide and Au(CN)z for adsorption sites will enhance the elution of gold, but plays a minor role at elevated temperatures. The most important effect of cyanide is its reaction with the functional groups on the carbon to passivate the surface for the adsorption of anionic metal cyanides and thereby promote the elution of gold. This passivation, caused by the degradation of cyanide, is strongly temperature dependent. Free cyanide in the elution step of an AARL elution is of lesser importance than the cyanide in the pre-treatment step. Elution without cyanide is possible only after cold acid washing, and has been proven on plant scale.

Jan 1, 1992

By A Black, J H. Youngson

At least 85 000 tonnes of mine tailings were discharged into Deepdell Creek, east Otago between 1890s and 1940s. The tailings contained about 1 wt % arsenic, so about 850 tonnes of arsenic in the form of arsenopyrite was discharged. Annual floods have removed nearly all tailings within c. 60 years. Small amounts of arsenic-bearing sediments (<250 ppm) remain in Deepdell Creek. About 7 kg/year dissolved arsenic was discharged in groundwater from mineralised Hyde-Macraes Shear Zone rocks in the vicinity of the historic mine sites. Adsorption of this arsenic on to iron oxyhydroxides in the stream sediments may have contributed to the elevated As content of those sediments. Even less arsenic remains in the main Shag valley below the Deepdell Creek confluence (15 - 25 ppm As). Rare relict arsenopyrite grains are trapped in bedrock crevices 25 km from source. No tailings deposition is detectable in theShag River estuary, and the tailings have presumably been discharged into the sea. Natural rehabilitation of the Shag catchment has been rapid and effective.

Jan 1, 2004

Dartbrook mine is a new greenfields thermal coal longwall mine located n the Upper Hunter Valley ten kilometres north of Muswellbrook Figure 1). Construction began in April 1993 with coal extraction starting n October 1994. Longwall production is scheduled to commence in the first quarter of 1996 with production expected to exceed 3.5 million onnes per annum. The permanent workforce will number 150 full-time ,mployees and productivity rates will be 22 000 per employee per annum m a ROM basis. Being a greenfield site Dartbrook has had the opportunity to develop and operate the mine using the best practices and latest technology available to meet high standards of safety, quality and production.

Jan 1, 1995

By A Atkins

Six recent case studies were selected based on the eight main causes of mine disasters (Table 1; Quinlan, 2014) and where credible information sources, such as Royal Commission Reports, Coronial Investigations and textbooks, were available. The six case studies are listed below. Details are available via this link or the conference PowerPoint accompanying this paper. 1. Beaconsfield, Tasmania – 2006 Fall of Ground/Seismic Event (Chandler, 2009; Melick, 2007; Wright, 2012). 2. Bingham Canyon, USA – 2013 Manefay Slide (Ross, 2017). 3. Bronzewing, WA – 2000 Hydraulic Fill Inrush (Hope, 2002). 4. Brumadinho and Samarco, Brazil – 2015 and 2019 Tailings Storage Facility (TSF) failures (Bowker, 2019; Darlington et al, 2019; Demajorovic, Lopes and Santiago, 2019; Morgenstern, 2016). 5. Northparkes, NSW – 1999 Cave Air-blast (Bailey, 2003; Hebblewhite, 2003). 6. Pike River, NZ – 2010 Methane Gas Explosion (Macfie, 2013; Panckhurst, Bell and Henry, 2012.

May 5, 2022

By R W. Shaw

The MTM Process targets treating lower grade and/or problem concentrates that are not attractive to smelters. The process has been developed at laboratory scale for copper and is based on a related development for zinc that has been extensively developed both in the laboratory and through pilot testing. The basis of the process is novel ammonia-ammonium chloride leach chemistry adapted to give high copper extraction whilst being selective over iron, arsenic and many other elements. The preferred flow sheet depends on location, especially infrastructure and utilities. These impact upon the leach and crystallisation stages more than copper reduction.

Aug 24, 2022

The Blackwater Coal Mine is a modern open cut operation using large draglines for over- :)urden removal and shovels, loaders and trucks to mine and haul coal to the crushing and coal ?reparation plant. Operations at the mine are described in sequence following through overburden removal to the railing of product coal from the mine site. The close operating connection between the mine and washery, which results from the blending of raw coal into clean product via the qashplant bypass system, is stressed. Some features of special interest at Blackwater Mine, such as land reclamation and slope stability,are outlined.

Jan 1, 1974

By Lewis RW, Tullemans FJ, Gallo JB

Gold mineralization at Kidston occurs in a semicontinuous zone near the margin of a large, late Palaeozoic breccia pipe. The pipe is ovoid in plan, funnel-shaped in cross section and straddles a contact between Proterozoic metamorphic and granitoid rocks which are intruded by a swarm of late Palaeozoic acid dykes. Rock fragments within the breccia pipe reflect the enclosing country rocks and mix in various proportions to form gradational lithological domains. Most of the gold is free and is located in the breccia matrix and in a set of inwardly dipping sheeted quartz veins which kink around the pipe margin. Sulphide minerals, dominantly pyrite, occur as disseminations in the breccia matrix and as aggregates in the cores of quartz veins. Hydrothermal altLration is pervasive within the breccia and is most intense in areas with the highest percentage of acid dyke fragments. Sericite and carbonate are the main alteration minerals. An empirically developed genetic theory for the formation of the breccia pipe and attendant mineralization involves magmatic and post-magmatic processes associated with the intrusion of a granitoid body to a shallow level in the crust. Economic evaluation of the deposit relied heavily on the results of diamond drilling. Both polygonal and geostatistical reserves were calculated and found to be in close agreement. Geostatistical reserves are considered to more closely reflect the tonnes and grade achievable during mining. Daily geological mine routine is strongly biased towards grade control allied with the practical aspects of open-pit mining. Tonnage/ grade correlations between ore blocks geostat- istically generated from exploration diamond core results and ore blocks generated from high

Jan 1, 1986

Underground space can be defined as space below natural ground level which can be used as an alternative to an above ground location. While many of our above ground structures inherently involve underground excavation for foundations and services, the term underground space specifically refers to organised development of underground openings and of the underground domain. For example, the services to a city such as power, gas, sewerage, water and communications are installed in a congested array which usually requires roads to be dug up when the services need to be accessed. An underground space installation of services would involve a well planned conduit which is easily accessed without any excavation. The concept of using this virtually untapped land resource to the advantage of our expanding cities is gaining considerable interest in Australia. Overseas, in the Scandinavian countries and some Asian countries, underground space has been used for centuries; in Great Britain, France and the United States of America over the last century and in Japan for over a decade. This paper focusses on the types of underground space usage which should be competitive with above ground use and suggests areas in which the competitive edge may be improved in favour of underground space. In particular, considerable advantage is seen by using well-planned underground space developments in major cities, where the strategic central location of the development takes advantage of proximity to potential users. However, the largest single factor affecting the acceptance of underground space is the high capital cost of construction, even though an underground space development may result in lower operating costs and reduced long-term maintenance costs. While excavation methods and associated costs are very much site-specific, the importance of applying the latest technology in rock breakage, with consideration of ground vibration, excavation rates and ground support, remains a major challenge to the development of underground space.

Jan 1, 1995

By Chander S

Properties of surface films on chalcopyrite and pyrite differ due to variations in the mechanism of oxidation of the two minerals. In the case of chalcopyrite the first step in the oxidation is the release of iron as ferric ions, which hydrolyse depending upon conditions prevalent in solution. The iron oxide/hydroxide layer formed by hydrolysis of ferric ions is quite porous and easily detachable from the surface of chalcopyrite. When the surface oxide layer is detached a sulphur-rich layer is exposed making chalcopyrite hydrophobic. The thickness and properties of the sulphur-rich layer determine its flotation response, both in the absence and presence of collectors. In the case of pyrite, on the other hand, iron is released as ferrous ions which require much higher pHs to hydrolyse. These ions remain adsorbed on the surface of pyrite making the surface hydrophilic. When the iron species are complexed with chelating agents such as ethylene diamine tetra acetic acid, pyrite was hydrophobic. Siderite forms in the presence of carbonate ions, which might be present in several flotation systems. Siderite nucleated on isolated sites at the surface. The presence of such a precipitate is likely to influence the interaction of pyrite with various reagents thereby altering its flotation behavior. To determine the mechanism of oxidation, kinetics of oxidation of chalcopyrite and pyrite was studied using several electrochemical techniques, namely, cyclic voltammetry, polarisation and impedance spectroscopy. Floatability of the minerals was investigated by measurement of contact angles on mineral electrodes and by Halimond tube flotation. Impedance spectroscopy was especially useful for estimating various properties of surface film for both the minerals. Properties such as charge transfer resistance, porosity, and capacitances of the surface films on the two minerals are compared under several conditions of oxidation. These properties were found to be a strong function of the rate and the extent of oxidation.

Jan 1, 1993

By Hatherly P, Holt GE, McNally G

The current methodology for delineating and subsequently evaluating coal reserves is based on the use of vertical drill holes and surface based geophysics/geology. These techniques have three major problems, these being respectively:-a) Vertical drill holes can only provide a small sample of the coal seam and stratigraphy. Therefore the planar variation in coal reserve and environment parameters can only be approximated.b) Although surface based geophysics has had its fair share of success in recent years, there are still environments which have masked the finding of major structures.c) Access to drill sites is difficult at some locations due to mountaineous terrain, standing water and environmental impact.

Jan 1, 1985

By R O’Sullivan, D Taylor, J G. McLellan, B Miller

The Mount Isa copper deposit is located adjacent to the city of Mount Isa, Queensland, and lies within a series of Palaeoproterozoic to Mesoproterozoic Superbasins. The deposit is hosted almost entirely within the Urquhart Shale (US), a unit of the Mount Isa Group sediments and part of the Isa Superbasin. The copper mineralisation is separated into two distinct orebodies: the X41 mine (1100 and 1900 orebodies) and the Enterprise mine (3000 and 3500 orebodies). The orebodies are situated in the hanging wall of the major controlling structures, the Paroo Fault, which has juxtaposed older basement Eastern Creek Volcanics against the younger Mount Isa Group sediments cf 1655 ± 4 Ma. Conjecture remains over the exact timing of this thrust event. However, it is clear that inflections on the Paroo Fault have a close association with the orebodies and are an important structural feature in the mineralisation of the Mount Isa copper deposit.The life-of-mine is reducing steadily and new geomechanical modelling techniques were employed to target structurally controlled mineralised zones in three dimensions. Following a structural review of the mine using underground mapping, structural data and core shed observations, a conceptual 3D mine model was constructed utilising existing data modelled in MineSight®. This conceptual model included all the main lithological units and structures. The conceptual model aimed to test the effects of deformation on the main lithological and structural components of the system and attempted to highlight areas of anomalous stress and strain that may indicate a higher likelihood of fluid focusing and mineralisation potential. This project was focused on testing the latter stages of a D3 event (NE–SW compression) and D4 event (SE–NW compression), which are considered to be responsible for the current location of the mineralisation.The fully coupled 3D finite element analysis models resulted in highlighting anomalous patterns of stress and strain and subsequent fluid flow as a result of the two deformation events. The NE–SW D3 simulation provided the best correlation with the known distribution of mineralisation. This event also indicated several areas on the Paroo Fault and within the US that have potential to host further areas of mineralisation. The SE–NW D4 simulation provided less of a correlation with known mineralised zones. However, this event may have been responsible for post mineralisation re-mobilisation of copper on a relatively small scale. Areas of maximum shear strain, shear stress, volumetric strain and fluid flow correlated well with areas of minimum principal stress and provided the best overall match with known mineralised zones. Furthermore, several additional highlighted areas provide a high potential for further discovery of copper mineralisation. Recent exploration drilling north of the Enterprise mine 3000 orebody, utilising geomechanical modelling as part of the targeting criteria, intersected copper mineralisation, providing further validation of the modelling results.CITATION:McLellan, J G, O’Sullivan, R, Miller, B and Taylor, D, 2014. Geomechanical modelling of the Mount Isa copper deposit – predicting mineralisation, in Proceedings Ninth International Mining Geology Conference 2014 , pp 197–206 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 18, 2014

By A R. Sale

This paper highlights two aspects of the mineral sands industry in Australia: the development of the industry from approximately 1870 through to 1980, and the author’s experience in the industry from 1966 to date.The first real heavy mineral (HM) mining in Australia started in 1870 with the mining of heavy mineral slicks on the beaches along the east coast of Australia. The real potential of Australian heavy minerals was however only realised in the 1920s with the first production of a heavy mineral concentrate that was shipped to Canada for processing. Post WW 11 and the Korean War, Australia was the largest producer of mineral sands products in the world as well as a significant developer of associated separation equipment and technology. The number of producing companies in the east coast peaked at 33 in 1957, was reduced to ten by 1965, and subsequently further reduced to five in 1980 as a result of potential mining areas being declared National Parks or Conservation Reserves. Today there is one company, Unimin Australia Pty Ltd (formally Consolidated Rutile Ltd) operating on the east coast. In contrast there were three companies on the west coast in 1965, four companies in 1980, and four companies today (albeit not the same companies).There have been considerable ups and downs for the industry in Australia, however world wide it was renowned in the past as being an industry that attracted numerous interesting and innovative characters that played a major role in developing it into the vibrant industry that it is today. This, given the current climate, is predicted to continue into the future.The author has been continuously involved in the industry for over 45 years from 1966, initially as an electrician at Consolidated Rutile Ltd culminating in the role of General Manager/President of Iluka Resources Limited USA, prior to his retirement in 2009. His exposure has been world wide and has covered all aspects of the industry but in the main focused on project development and operational areas. During this time there have been significant technological advances, yet to some extent the basic principles have not changed at all. Some of the most noteworthy advances include the development of the Wright Spiral in 1977, the development of the Reading High Intensity Wet Magnet (WHIMS), the rare earth magnets, the CRL floating thickener and the improvement of analytical techniques. From a safety, health and environmental perspective there has been significant advances that the industry has much to be proud of. These include wetland restoration both in Australia and in the US, the restoration of farmland in Virginia and Capel, and the re-establishment of native species, for example at Eneabba and Richards Bay to name but a few.

Oct 5, 2011

By Fejes A. J

The U.S. Bureau of Mines installed surface and subsurface instruments at a mine site in Colorado to monitor and characterize the overburden response to longwall mining. Instrumentation included a time-domain reflectometry (TDR) cable, a multiple-point borehole extensometer (MPBX), vertical- deformation surface monuments, and in-mine pressure cells for monitoring abutment, pillar, and gob loads with respect to the longwall face position. The purpose of the study was to collect data that could be analyzed to correlate the design of the mine layout to the resulting overburden failure response. Determining the extent of caving and fracturing is important in the and and semiarid Western United States because of the possible consequences to the fragile underground hydrologic systems upon which the land owners and users depend. This study is unique from past investigations because the overburden contains massive sandstone members that impose special conditions on the caving process and pressure redistribution above the longwall panels. This paper presents the results of this correlation study.

Jan 1, 1992