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By Windsor C. R, Thompson A, Bywater S

A new high tensile strength, steel cable, that may be grouted into boreholes has been developed for use as rode reinforcement. The manufacturing technique produces a birdcage pattern in which the cross section varies along the length of the cable. The load transfer from cement grouts to birdcage cables has been demonstrated in laboratory tests to be better than that of standard 15.2 mm diameter seven wire cables. The manufacturing process also allows for a wide range of capacities which may be specified by design engineers. The various birdcage cable configurations have been applied as rock reinforcement in a number of Australian underground and surface mines.

Jan 1, 1990

By S Hanke, J Burden, P Spies

The Waterview Connection will complete Auckland’s long-planned Western Ring Route, a 48 km north-south motorway alternative to State Highway 1 that bypasses the central city to the west. The project involves construction of 5 km of new motorway – half of it underground in tunnels – to connect the Southwestern (State Highway 20) and Northwestern (State Highway 16) motorways.The Western Ring Route will link the major population and industrial centres of Manukau, Auckland and North Shore to give the region the connected and resilient strategic road transport system it needs to underpin economic growth and sustainable development. It will also provide a direct motorway link between Auckland’s central business district (CBD) and international airport.The project involves construction of twin 2.4 km driven tunnels with an outside diameter of 14.41 m beneath residential suburbs, a major arterial road and a rail corridor. Enabling works began in January 2012 while tunnel construction using an earth pressure balance (EPB) tunnel boring machine (TBM) began in November 2013.This presentation introduces the Waterview Connection project, its role in the development of the Auckland motorway network, its procurement process, the alliance delivery model and an overview of the project’s design features and construction progress to date.Design and construction highlights of the presentation include the TBM start-up, turnaround and breakthrough arrangements as well as the experience gained during the first tunnelling drive. The presentation also covers an innovative process developed for invert construction behind the TBM that is independent of tunnel excavation.CITATION:Spies, P, Burden, J and Hanke, S, 2014. The Waterview Connection Project – progress to date, in Proceedings 15th Australasian Tunnelling Conference 2014 , pp 519–540 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 17, 2014

By S Phinn, V Glenn, P McKenna, P D. Erskine, D Doley

The key goals for mine site rehabilitation require mine managers to demonstrate that rehabilitation is safe, stable, self-sustainable and non-polluting. Within this context, it is reasonable for stakeholders to expect that mine site rehabilitation is resilient to disturbance impacts such as fire and drought. However, mine managers actively avoid fire on rehabilitation; and as a result have limited understanding of fire behaviour on revegetated landforms, the long term implications for site stability and the potential risk to site relinquishment. An experimental fire that was conducted at the Curragh Mine site in May 2015, burnt 117 ha of 19- to 21-year old mine site rehabilitation, mimicking wildfire conditions and creating a mosaic of fire impacts across the landform. Using a combination of ground surveys and remote sensing assessments, we demonstrate that over a two year period, ecological metrics such as species richness, woody density and understorey biomass all recover to pre-fire levels for both grassland and open woodland areas. This is supported by WorldView-3 satellite imagery and the remote sensing assessment using the differenced Normalised Differenced Vegetation Index (dNDVI) which shows high regrowth within the burn area in 12- and 24-month image captures. The results suggest that within the recorded conditions, this site is resilient to fire impacts, and has the capacity to recover to pre-fire levels within the first two years following the fire.CITATION:McKenna, P, Erskine, P D, Phinn, S, Glenn, V and Doley, D, 2018. Measuring the recovery of coal mine rehabilitation following fire in Queensland using remote sensing and ground surveys, in Proceedings Life-of-Mine 2018, pp 141–146 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 25, 2018

By Edmonds W, Giles C. W, Webb R. J, Gum J. C

Gold production from The Granites - Tanami Goldfield during 1993 is expected to exceed 8 t, eclipsing that of the traditional Northern Territory gold mining districts of Tennant Creek and Pine Creek. This is the result of dedicated and successful exploration, and the consequent discovery of new orebodies such as those at Dead Bullock Soak.Following granting of access to regional exploration areas in 1988 and identification of favourable host rocks in the Schist Hills area, North Flinders Mines (NFM) began a methodical exploration program of detailed geological mapping, rock chip sampling, costeaning and various types of drilling. The first resource of 600 000 t of 3.3 g/t gold was announced in mid-1989. This has grown progressively with systematic exploration to the currently published resource inventory of 6.6 mT @ 5.4 g/t, (as at 31.12.92) contained in six separate orebodies within the Dead Bullock Soak Mineral Lease at Schist Hills.

Jan 1, 1993

By M Hassall, E Humphries

Personal risk assessment processes, also known as Take 5 or SLAM (Stop, Look, Assess, Manage) have been utilised in high hazard industries for over 30 years. However, there is limited research to understand if a personal risk assessment process improves safety and health outcomes. The author’s learnings during discussions with training participants in G3/G-MIRM (Risk Management Systems) and G2 (Risk Assessment for Supervisors) courses have provided them with significant insight into understanding if a personal risk assessment process is valued across a number of mining industry organisations. These discussions arise when the four-layer model is presented (Figure 1) where ‘Layer 4’ represents the last resort risk checking activity. In this context, training participants agree that this process has value. However, the consistent opinion is that the personal risk assessment process is not effective, that it is a ‘tick and flick exercise’ and is not achieving the desired outcomes.

Apr 16, 2024

By Freeman N

A microcomputer based control system has been developed and implemented at ZC Mines (now Pasminco Mining). The control system maximises throughput at a product size set point while maintaining a "safe" cyclone underflow and mill operating pulp density.To characterise mill and cyclone operation over a range of ore types, 60 circuit surveys were carried out by ZC Mines personnel over a period of four months. The data for each test were model fitted to check for data consistency and to accurately estimate circulating loads.The model fitted results were combined with instrument readings (including in-stream analysis probe assays) and the data checked for ability to predict key variables such as product size and underflow density from measurable inputs.In the resulting control scheme, panicle size and underflow density are not monitored directly, but are predicted by regression equation models based on directly measured variables. The tonnage control loop uses a dynamic model to maximise responsiveness.The system provides a data log output to an mM compatible personal computer at programmable intervals. Comparative data logging over a period demonstrates substantially smoothed circuit performance.The grinding control system was originally implemented using Fischer and Porter micro-DCI controllers. The program has also been implemented on a distributed control system using a sequence oriented programming language.

Jan 1, 1990

By B Arthur, K Sexsmith, D Hockley, S D

At the proposed Crandon Project, mill tailings would be depyritised for upland disposal. The resulting pyrite concentrate would be disposed of in the underground workings as a cement-amended paste backfill. In the long term, the underground workings would be flooded and the potential for the paste backfill to generate acid would be limited. However, while the mine is operational, there is potential for oxygen ingress to the backfill that may lead to sulfide mineral oxidation and acid generation. A series of humidity cell tests were completed to assess the potential for groundwater contamination. To assess effects of surface area on oxidation, the humidity cell tests were conducted on moulded cubes of paste backfill. The tests were terminated at different intervals, and the cubes were dissected and examined mineralogically. Various leach extraction procedures were also used to assess the progress of oxidation and secondary mineralisation within the paste backfill. The test results showed that: the cement amendment significantly contributes to acid neutralisation and results in a lag in excess of one year before the onset of acidic conditions (in comparison to less than three weeks for the pyrite concentrate); the depth of oxidation in the paste backfill is restricted to about 1 mm after 107 weeks of testing; and secondary minerals form a distinct ærindÆ at the surface of the paste backfill. The results indicate that acid generation in the backfilled stopes would be minimal. The importance of including the surface area effect in the testing (ie using moulded cubes) is clearly demonstrated.

Jan 1, 2003

Comminution Kinetics equations are developed to take into account difference of grindability of mineral components. The equations describing both batch and closed circuit grinding or crushing processes are given. These equations are applied to industrial data to derive comminution kinetic and classification characteristics of the component minerals in a multi-mineral ore. Control strategy based on these concepts is presented.

Jan 1, 1985

By S C. Dominy

The Minerals Education Australia program is offering a tertiary learning environment for the global mining industry. The Minerals Council of Australia has instigated this initiative, which is run by the Minerals Tertiary Education Council. The program is a pioneering partnership between the Australian minerals industry, Australian governments and key Australian universities. It is designed to deliver key undergraduate and postgraduate courses for tomorrowÆs minerals industry professionals in the fields of geoscience, mining and minerals engineering and metallurgy. The flagship course for geoscience professionals is the G3 Masters program. This is a coursework-based degree supported by the Minerals Tertiary Education Council, and a partnership between James Cook University, the University of Tasmania and the University of Western Australia. These partners represent the leading-edge providers of minerals geoscience education and R&D in Australia. The G3 program provides the full spectrum of post-graduate training skills in exploration, mining and economic geology topics.

Jan 1, 2003

By C Preston, T Williams, D Roy

The easiest way to mine valuable orebodies is through the use of explosives and well-planned blasting layouts that produce fragmentation profiles designed specifically for conveyance equipment in underground mines. The design of blasting patterns is specific to not only the explosives being used but also the rock or ore type being fragmented. Many blasting designs are based solely on the experience of those developed for similar orebodies in terms of properties and orientation or individuals that have some blasting experience.The primary technical objective of this paper is to outline a unique methodology for determining underground blasting methodologies (developing specific blasting parameters) commensurate with explosive energies and rock/ore equations of state for a narrow-vein gold property located in Northern Quebec and for underground mines in general.The procedures developed are to define the desired fragmentation specification so that a specific thermodynamic break is generated, taking into account powder factor, energy factor, tonnages, explosive energies and distribution along with blasthole diameter and orebody orientation for a specific set of explosive and dynamic rock/ore properties. Determining dynamic modulus values for the ore using seismic sensors to measure P- and S-wave velocities, the aforementioned parameters will be utilised to set the design constraints to maximise recovery and minimise overbreak and dilution.New underground blasting software (AEGIS) will use thermodynamic break in conjunction with defined fragmentation profiles to create an array of blasting parameters used to design and plan ring layouts. This software will also allow mining planners, prior to drilling and loading a production blast, to appraise future intended blasting patterns to minimise the potential of diluting ore with host rock and the likelihood of damaging mine support structures.CITATION:Roy, D, Williams, T and Preston, C, 2015. Underground stope drill and blast designs optimisation program, in Proceedings 11th International Symposium on Rock Fragmentation by Blasting, pp 137–148 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 24, 2015

By B Tutmez

Determination of stress-strain behaviour of rocks plays a crucial role in understanding the response of rocks during loading. However, it is a tedious, expensive and a time-consuming process to obtain such characteristics both in the laboratory and in situ. On the other hand, non-destructive testing methods such as ultrasonic velocities can produce a reliable and fast solution to indentify state of strain and stress in rocks. The present paper aims to provide insight into the relations amongst ultrasonic wave velocities, amplitudes and deformability properties of porous siltstone under compressive loading. For this purpose, pulse (vP) and shear wave velocities (vS) along with amplitudes (AP - AS), and applied loads with resultant strain were measured simultaneously so that response of siltstone to compression can be evaluated. In addition, initial vP and vS were recorded at the beginning of each test to calculate dynamic elastic properties of the specimens. This provided a comparison between static and dynamic elasticity properties of siltstone. Crack damage associated with the onset of dilation was also investigated. The results showed that there is a non-linear logarithmic relation between velocities and stress-strain level for siltstones.

Sep 26, 2011

By Gregory L. M, Phillips G. N

Although it has long been recognised that there is a diversity of minerals associated with Victorian gold deposits, the degree to which this mineralogy is systematic or haphazard has remained uncertain. Recent work by the authors and students under their supervision permits a sharp delineation of the boundaries between different mineralogical domains, and these are interpreted in terms of recent rapid advances in Victorian tectonics, and the regional framework of Victorian gold geology described in Phillips and Hughes (1996).

Jan 1, 1997

By Moskovits EE

Spodumene was recovered from pegmatite by flota.ticn in lAoretory tests and ;pilot-plant, operation using an anionic collector e1 ulsi3.n. i sir_tilar process applied to beryl pegmatite g^.ve encouraging results.

Jan 1, 1963

Deposits of chromite are in associated with ophiolite complexes in Papua New Guinea. No deposits which are currently exploitable have been recognised, but large resources that may be economic in the future are present at Ramu area and on the Morobe coast. These are contained either in laterites or in sediments derived from ultramafic members of the ophiolites. There are possibilities of establishing further resources either in similar settings or associated with ultramafic members of alkali intrusive Complexes.

Jan 1, 1987

By J Rayner, R P. Langmead, J A. R Coote

Gosowong is situated within the Neogene magmatic arc of Halmahera island in the Maluku province of eastern Indonesia. It was discovered as the result of a rigorous ground reconnaissance program in an area with no previous mining activity. The broad structural setting in the Gosowong District comprises an elongate dome formed by the forceful upward intrusion of magma along a deep-seated structure, resulting in associated tensional fracturing trending parallel to the long axis of the dome. Four copper-gold porphyries and numerous low-grade epithermal veins occur within this mineralised corridor, with the Gosowong Deposit being the only economic occurrence discovered to-date. Gold mineralisation is hosted within multiphase epithermal quartz-adularia and quartz-chlorite fissure veins, breccias, and stockworks. High-grade gold mineralisation is emplaced in two gently south-plunging ore shoots along a 400 m section of the north-striking, east-dipping, Gosowong Fault, the primary control on mineralisation. The Gosowong Fault is believed to be a tensional fracture associated with uplift of the dome. Lithological variation and structural intersections play a large role in grade distribution within the vein zone. Host rocks comprise a wide range of shallow marine, intermediate-basic volcanic and volcaniclastic rocks of ?late Miocene age. The Gosowong gold deposit is a classic example of a low-sulphidation epithermal gold deposit, based on the abundance of adularia and illite in the alteration assemblage, and low base-metal sulphide content within quartz-adularia veins. The indicated resource is estimated at 0.99 Mt at 27 g/t Au and 38 g/t Ag for a total of 870 000 ounces Au, using a cut-off grade of 2 g/t Au.

Jan 1, 1999

By Dredge K, Becker G

The successful dissolution of the valuable metal components of a solid phase is often a basic requirement for a successful hydrometallurgical treatment process. Sulphide concentrates are often an intermediate product in the production of refined metals. These concentrates need to be further processed to realise the contained metal values in a useful form. Pyrometallurgical techniques have tended to dominate, at least the initial treatment of metal sulphide concentrates. The technology described, Activox«, has been developed specifically for the hydrometallurgical treatment of these sulphide mineral concentrates, in particular those containing copper, nickel or gold. The Activox« dissolution technology coupled with the use of existing, or newly developed, downstream processing techniques, offers alternative processing options for the recovery of full value, saleable metal products. The technology is suitable for application down to relatively small scales opening up the opportunity for on-site production of metals even at modest scale mining Operations.

Jan 1, 1995

By M Chen, W S. Ng, Y Liu

In the processing of refractory gold-bearing sulfides, pressure oxidation (POX) is commonly known for its role in liberating the gold in solid-solution via oxidation of the sulfide occlusions. For deposits that contain arsenic-bearing species including arsenian pyrite and arsenopyrite, POX serves an important secondary function in the fixation of arsenic, via the hydrothermal precipitation of stable arsenates such as scorodite and basic ferric arsenate sulfate (BFAS). There have been various investigations on the impact of different POX conditions on arsenic precipitation and the stability of the formed phases, but less is known about the changes to the arsenic carrier that occur in the curing stage, which follows directly from POX. The primary function of curing is to coax the dissolution of sulfates to reduce lime consumptions during cyanide leaching, and the slurry is kept at elevated temperatures near 100°C to achieve this. While the arsenic-bearing phases are expected to undergo transformation during this stage, there has thus far been limited experimental evidence. In this study, the effect of curing time and curing temperature on the arsenic-bearing species and arsenic deportment in the POX product has been investigated. Leaching of the curing products was also conducted to examine the stability of the arsenic species in the solid precipitates.

Aug 24, 2022

The coal basins that formed near the margin of Permian Australia were comparable in size with the Appalachian coalfields and with the European fields between Wales and Poland. They formed on the foreland side of a growing orogen in a system of linked transform basins formed by transtension on strike-slip faults. They were terminated and compressed when the Gympie volcanic arc was accreted to the orogen. Another huge system of Permian coal basins extending far inland from the Permian coast was also terminated when the Gympie Terrane was Accreted.

Jan 1, 1987

Hoisting ropes are constructed of wires and strands positioned helically around the axis. This helical positioning causes that, in the rope loaded at the end with the weight Q, the longitudinal displacement u, axial force P, torsional displacement v and constant torsional moment M are generated. More over, the proper weight of the rope q gives the force acting along the axis of the rope. This force changes its value from 0 at the bottom to qL at the top. This force gives, along its length, a variable torsional moment making the rope rotate. During the movement of the conveyance downwards the falling part of the rope rotates, which makes it untwist on the section up to the half-depth of the shaft and twist on the other half-depth. As the result, the twisting lay of the rope changes increasing in the upward direction and decreasing downwards. The angle of twist of the strands changes in an apposite way. When moving upwards, the uplifted rope does not twist and retains its state of deformation up to the moment when it passes over the pulley. Next, the cycle of untwisting and twisting repeats during the movement of the other conveyance downwards. This phenomenon is known from mining practice. It was also analysed, in the works of Glushko (1966) and Popowicz (1963).

Jan 1, 1995

By Baafi EY, Chatterjee PK

The quality of mine planning decisions ultimately depends on reliable estimates of the characteristics of the orebody. The quant- ifiable factors such as grades or thickness can be estimated from field data gathered from outcrops or exploratory drillholes. Since outcrop data is necessarily limited to the periphery of a deposit, extensive drilling generally is required. This paper outlines a method for selecting the number and location of additional exploratory boreholes using an iterative procedure based on a mathematical optimization concept called fixed point theory. The method is illustrated through its application to an exploratory drilling program for a coal mine where optimized locations gave a lower estimate of regional and block variances than a manual Choice.

Jan 1, 1986