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By Hussey K. J, Morrison R. S

Recent mapping (1989-1992) by the Northern Territory Geological Survey in the Tennant Creek 1:250 000 map sheet area has resulted in substantial revision of the lithostratigraphy of the Tennant Creek Block (Donnellan, Hussey, and Morrison, in press). Briefly, the former Warramunga Group (Dunnet and Harding, 1967; Dodson and Gardener, 1978) is divided into the Warramunga Formation, and an overlying less deformed volcano-sedimentary succession, the Flynn Subgroup. The latter is conformably overlain by the Tomkinson Creek Subgroup of the Tomkinson Creek province in the north of the Tennant Creek Inlier. These two Subgroups constitute the Churchills Head Group which is essentially equivalent to the Hatches Creek Group of the Davenport province to the south of the Inlier.

Jan 1, 1994

By Rosmus P

Improper use of auxiliary ven- tilation units during heading operations may often result in the appearance of hazardous methane accumulations. This is the case especially when roadways are ventilated by a combined system with a short sucking pipe at face end performing as the dedusting installation. Uniform air inflow to the face end facilitates sucking off the dust clouds and creates conditions favourable for formation of local methane accumulations. The highest methane concentration occurs in the cutting zone between the rock cut and the pipe inlet, under the roof and by, the sidewalls. Permanent monitoring of methane concentration at face end employs methane sensors. The most important are: one on the road- header's boom behind the cutting head, and one at the air outlet from the dedusting installation.

Jan 1, 1988

Gold mineralization belt of eastern China in the adjacent part of the northwestern Pacific rim is orientated NE to NNE and as-sociated with Mesozoic faults and igneous intrusives and Mesozoic to Cenozoic volcanism and subvolcanism extending more than 3000 km in length and 300 to 800 kni in width affected by the movement from the Pacific Plate subducted against the Asian Plate.The relative movement between the Pacific and the Asian plates give rise to two types of fracture zones, the tensional ones providing the space for the formation of fissure-filling type of auriferous quartz veins and the shear zones providing the space for the formation of hydrothermal replacement type of gold de-posits in Shandong Peninsula. The fissure filling type of quartz vein, is represented by Linglong gold deposit which is hosted in Mesozoic Linglong Granite and consists of hundreds of quartz veins filling fractures trending NE to NNE and the hydrothermal replacement type is represented by Sanshandao gold deposit which is hosted in crushed and hydrothermally altered Mesozoic Linglong Granite in contact with Archaean metamorphic complex of Jiaodong Group along a Mesozoic upthust fault zone trending NE.

Jan 1, 1990

By A Annor, L J. Chen

The production of paste backfill has typically been accomplished through the adaptation of existing technology. Thickeners and disc filters have several drawbacks when applied to production of tailings paste backfill. Personnel at CANMETÆs backfill research laboratory in Sudbury, Ontario, Canada have been carrying out research into and development of methods to produce paste backfill using total mill tailings since 1991. Using a silo for production of paste is not a new concept but has been refined to a marketable level. This technology is based on a fluidization principle that assists in settling the tailings to an homogenous state in a silo. Other developments include patented de-watering technology for use in the silo to speed the settling of the solids to a suitable solids content, optimisation of silo geometry, and instrumentation related to paste backfill production and transportation. The advantages to fluidisation technology are in reduced capital cost, reduced operating costs and in the environmental benefits of using full plant tailings over classified tailings or alluvial aggregates. Another major advantage is in the ability of this technology to be retrofitted to existing hydraulic backfill plants to further reduce capital cost. This paper details the development of the new technology as well as the associated cost savings over other technologies. It will also look at the research and development of unique components that make this technology work.

Jan 1, 1998

By Chitombo GPF

The dilution of blasted ore with cemented backfill materials has been recognised as a significant factor influencing the economics of some underground metalliferous mining operations. Several mechanisms have heen identified as possible causes of fill failures. The purpose of this study was to determine the possibility of damage as the result of one mechanism, that of production blasting adjacent to bodies of cemented hydraulic fill (CHF). A vibration amplitude transfer function has been developed to model the transmission of blast vibrations from the source, through ore, across the ore to CHF interface and into the CHF mass. The model may be applied in the near field. The model has permitted estimation of vibration amplitude at a point in a CHF mass, to which damage criteria may be applied. A number of assumptions and simplifications have been made to render the problem relatively tractable. Ore and CHF material characteristics recorded by a number of authors were utilised to formulate preliminary damage estimations. A simple application of the amplitude transfer model indicated that a zone of plastically deformed CHF would be produced, and would extend to a distance of approximately 0.5 metres from the interface into the CHF. A sensitivity analysis was also conducted, that indicated that the zone of plastic deformation would be more extensive given appropriate conditions. Recommendations for further model development and future laboratory and field investigations have been made.

Jan 1, 1998

By M Noakes

EcoTechnology refers to a series of potential metallurgical processes for complex ores, concentrates, tailings and slags that are all based on an initial chlorination step at low to moderate temperatures probably in a fluid bed chlorinator (FBC). Examples of the research and development (R&D) results are provided in this paper for a high grade Au/Sb Leach Tailings (EcoGold<sub>®</sub> Process), a very refractory sulphide Au concentrate, a refractory gold calcine tailings, a Cu/Au tailings (EcoCopper<sub>®</sub> Process), bulk polymetallic sulphide concentrates and polymetallic sulphide/oxide complex ores (EcoZinc<sub>®</sub> Process and EcoLead<sub>®</sub> Process). R&D on over thirty different ore types has been conducted at a bench scale as discussed. Latterly a dedicated pilot plant was designed and constructed by EcoTech Mining Pty Ltd (EML) and several of the different feed stock results have been confirmed by pilot plant testing. It is planned to scale up to a commercial demonstration plant. To demonstrate the versatility of EcoTechnology, bench and pilot plant test results on five of the projects are used as case studies as follows: Fosterville ‘leach tailing’, VIC; Wiluna flotation concentrate – BIOX Feed, WA; Wiluna calcine facility tailings, WA; Mt Morgan Cu/Au tailings, QLD; Polymetallic sulphide concentrates from Pegmont Deposit, QLD and Polymetallic sulphide/oxide ores from Commonwealth Mine Project, NSW. CITATION: Noakes, M, 2018. Improved recoveries and environmental outcomes from complex ores utilising EcoTechnology, in Proceedings Complex Orebodies Conference 2018, pp 122–123 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 21, 2018

By S Sullivan

The key skills for a competent geologist are observation, documentation, analytical thought and the ability to communicate. These attributes have served the geological world for the past two centuries since the field of geology was separated out from natural philosophy. The understanding of the structural setting, lithologies, alteration and 3D distribution of the target mineral species are essential precursors to resource evaluation and potential economic extraction. The advent of artificial intelligence and machine learning has matured to the point where observation by dedicated sensors and analysis by customised AI algorithms can replace manual processes and deliver credible results. In combination with analytical data such as assays, various sensors now collect physical properties of rocks which are used as proxies for mineral identification and rock mass classification. These sensors include X-ray and infra-red spectra, magnetic susceptibility, gravity/density, EH/pH measurements, conductivity, colourimetric readings, porosity, fracturing and fracture intensity. Analysis using machine learning techniques trained using known data sets can determine rock type classification, rock density, quantification of grade/quality attributes, mineral alteration, weathering and geotechnical attributes such as rock quality. This type of data relies on calibration and quality control of a variety of different types of electronic hardware. The resulting data is non-additive, has error ranges and will be suitable for consumption by fast AI methods providing probabilistic analysis. A second stage could include geometallurgical constraints to provide an ‘extractability index’, which is of more interest to miners than pure geotyping. Using resultant interpreted geological criteria, 3D domain models with spatial attributes will be built.

Sep 1, 2024

By Watson DF

Calculation of the amount of metal in an ore deposit or mining block should be approached by multiplication and integration of appropriate numerical manifolds describing the spatial distribution of the relevant variables, viz. grade, specific gravity and also thickness for bivariate data. Construction of a numerical manifold necessarily involves some form of interpolation but detailed characteristics of this are often not specified in various automatic methods, some of which even provide manifolds with discontinuities. A manifold used in calculations should describe in a geologically plausible way the spatial distribution of the variable of interest. Different approaches to the problem are discussed and compared. Particular computational inconsistencies emerge when "accumulation" is used as a variable in calculations of average grade. If an ore deposit is variable in relation to its sampling and especially if selection of mining blocks according to grade cut-off is a necessary operational decision, the biases introduced by accumulation methods can bring about serious problems of over-evaluation. Modern computational techniques make unnecessary the use of accumulations; because of potential inconsistencies it would seem unwise to use them in any ore reserve computation.

Jan 1, 1987

The basic methods to remove material from underground mines are to: convey continuously, batch in trucks, or batch in a shaft hoisting system. A critical aspect in shaft hoisting is accurately batch loading the conveyance or skip. During the 20th century, the almost universally accepted method of loading was via a measuring flask. A measured quantity of material was filled into the flask as the conveyance traveled through the shaft and then, when the conveyance arrived at the loading position, it was ædumpedÆ into the skip for hoisting. Two skip loading conveyor systems have been developed in Australia: BHP BillitonÆs Cannington Hoisting System, installed in 1996, is believed to be the first conveyor loading system designed for two skips. Two parallel conveyors were installed with a two-way gate controlling feed onto each belt. Cannington was ideally suited to conveyor loading as the very high ore density and relatively low production rate required a relatively small volumetric storage capacity on the weighed belt. Newcrest MiningÆs Telfer Hoisting System, which is to be commissioned in 2005, consists of a single slewing conveyor loading each skip with 32 tonnes of ore. The development of this system eliminates the two-way transfer, improves the accessibility and minimises the excavation required. While every hoisting system must be considered on its merits, conveyor loading offers significant advantages to the Mining Industry in the 21st century.

Jan 1, 2005

By Morrison R. D

This paper describes major events in the design, construction, camtissioning and operation of the Elura concentrator. It covers the period fran September, 1974 when laboratory testwork on drill core cotmenced to March, 1983 when the concentrator catmenced operation on run of mine ore following successful completion of initial ccnmissioning tests. The concentrator was designed to treat 1.1 million tonnes of lead-zinc-silver ore per year with a plant availability of 89 per cent. This treatment rate has been achieved for test periods.

Jan 1, 1983

By J J. Cilliers

The aim of this paper is to give an overview of the FrothSim flotation simulator and to demonstrate its ability to predict the performance of real flotation circuits. Example simulations are presented in which the feed rate to the circuit is varied, followed by simulations in which a cleaner section and recycle loop are added to the rougher bank.The simulator is able to predict both the recovery and the grade produced by the cells at all locations in a circuit and the simulator is shown to produce plausible grade recovery curves. It also demonstrated that the performance of banks of cells improve as the feed rate to the bank increased (improved grade for a given recovery), but that more cells are required to give the same overall recovery.

Jan 1, 2005

To gain further understanding of the operating efficiency of the BHP Slab and Plate Products Division (SPPD) RH vacuum degasser, physical and mathematical model studies of the process have been undertaken. The purpose was to investigate how the various process parameters affect the liquid circulation rate, to visualise the flow patterns, and to identify and eliminate the cause of localised wear in the downleg. In the physical model mixing times were measured using an acid tracer technique. The results were applied to predicting trends in times required to obtain homogenous melt composition under varying conditions. A 2-dimensional mathematical model describing the liquid metal flow has been developed using the PHOENICS fluid-flow package. The physical model results were simulated and incorporated into the mathematical treatment and an improved design for vessel geometry is proposed. The effect of rounding the downleg entrance or installing a baffle between the legs is discussed.

Jan 1, 1987

By J Sigda, T Jones, D Staggs, J Ewing, C Cheng, J Pickens, S Paulka

Mine-derived solutes from Energy Resources of Australia’s (ERA’s) Ranger uranium mine have been closely monitored for decades. Ranger is surrounded by the Northern Territory’s Kakadu National Park and is upstream of Ramsar convention wetlands. Modelling of groundwater flow and solute egress from mine wastes to surface waters has helped ERA successfully assess closure options and secure intermediate regulatory approvals during the site closure process. Potential environmental impacts were assessed using groundwater modelling in support of three ERA applications involving disposal of tailings-derived mine waste. Model results were an important part of the basis for obtaining regulatory approval. Three case studies are presented describing the three applications and how the groundwater modelling supported approval of the applications. For case study #1, INTERA supported ERA in addressing stakeholder concerns in 2017 regarding two aspects of tailings deposition in Pit 3. The first was the potential for flow of tailings fluid into the surrounding formations during tailings deposition. The second was the difference in post-closure magnesium (Mg) loading to surface water for two tailings deposition scenarios. INTERA developed a two-dimensional (2D) model that showed excess tailings pore pressures would not cause outflow and solute egress from the pit during deposition. INTERA’s three-dimensional (3D) models demonstrated that post-closure Mg loading to creeks for both tailings scenarios differed marginally and would be a small fraction of natural creek Mg loads. The modelling results helped avoid delays in completing tailings deposition driven by stakeholders’ environmental concerns. Case study #2 consisted of supporting ERA’s 2019 request for approval to change the tailings deposition method and final tailings level in Pit 3. INTERA’s model results for the permitted and proposed deposition methods showed minimal differences in post-closure Mg loading to creeks. The model results helped ERA obtain the needed approval for the tailings deposition method and water and tailings levels in Pit 3. For case study #3, INTERA modelled the comparative impacts from leaving the entire contaminant plume from the temporary tailings storage facility (TSF) in situ or excavating a portion of the contaminated material from beneath the TSF floor and placing it in Pit 3. The modelling results supported an approved TSF contaminated material application important for ERA to stay on schedule and minimise both closure costs and environmental impacts.

Jul 1, 2021

Alcoa of Australia's Del Park mining op eration is centred 9 km. east of the Pinjarra alumina refinery, and is centrally locatedwith- in the 10, 000 sq. km. lease which the Company holds for bauxite in the Darling Ranges. An- other mining operation is situated near the township of Jarrahdale, and supplies bauxite to the Kwinana refinery. Definition of the bauxite ore, development works and mining to the ore haulage stage, are identical for both mining operations. Exper- ience, and production cost figures, obtained from the Jarrahdale mine, where 100 tonne trucks are used to haul ore to a fixed crushing plant, led to the development of the Del Park mining concept with increased mobility of op- erations. The crushing-conveying-stockpiling arrangement at Del Park consists of a 1200 t. p. h. mobile crusher feeding bauxite to an overland conveyor system which transports the ore approximately 6. 66 km. to the stockpile area in the refinery. In the refinery raw mat- erials area the bauxite is distributed into 200, 000 tonne stockpiles by means of a travel- ling boom stacker.

Jan 1, 1973

Structural assemblages of veins, shear zones, and wallrock alteration zones arising from fault-valve action on steep reverse fault systems are reviewed using observations from mesothermal gold-quartz lodes in the Archean Yellowknife, Abitibi, and Yilgarn greenstone belts of Canada and Western Australia, the Cretaceous Mother Lode system in the Foothills Metamorphic Belt of the western Sierra Nevada, California and the Victorian goldfield hosted in a folded quartz-turbidite succession of Paleozoic age in Australia. Despite differences in the host rock assemblages, the deposits have many structural characteristics in common. These form a useful exploration guide when re-evaluating comparable, but poorly described gold-quartz vein systems such as those in the Reefton area of New Zealand.

Jan 1, 1992

By P SSrkkS

Mining is commonly seen as a typical basic industry with rough and even dangerous working conditions, heavy environmental load, and a low level of high-technology and automation with much manual work and operations. A mining operation (open pit or underground) is a very complex one consisting of many manual, physical, mechanical and logistical operations with different human interfaces and decisions. For this reason it is a demanding and potential area for all applications of automation and information technology: controlling difficult non-linear, time varying multivariable processes and machines; solving of ergonomic safety and environmental problems; automation of logistical systems; applying robotics, mechatronics, and information handling, etc. In addition to that, big economic sums are involved with these operations. On the other hand, automation technology has developed towards intelligent and adaptive systems including some from the above mentioned fields of automation. Connecting them with modern information and communication technologies makes the idea of an intelligent and unmanned mine more and more feasible in the near future. This requires intensive co-operation and co-ordination between the mining industry and manufacturers of mining machinery. This has been successfully accomplished in the five-year Intelligent Mine research and development program as well as the three years of subsequent implementation of its results in Finland. The basic elements of an Intelligent MineTM concept are:mine-wide information and data acquisition system; high-speed two-directional mine-wide communication network for real-time monitoring and control; computerised information management, mine planning, control and maintenance systems; automated and tele-operated machinery and equipment which are connected to the information system; and links to the public information networks. The degree of automation of an intelligent mine depends on many technical and economical factors. The basic precondition for such an approach is that it will improve the total economy of the mine. This paper will describe the Intelligent Mine Technology Program with the results. Also the implementation which took place during starting of a new underground mine (Outokumpu Chrome Oy Kemi Mine) will be described.

Jan 1, 2000

By Nolan D. P, Balales M

Over the last two years work has been undertaken within the Pasminco Metals - BHAS Zinc Plant to improve the efficiency and maintain the production capacity of the operation. The work has centred upon the installation of suitable process instrumentation to improve process control and the development of new unit operations to maintain control of the circuit water and sulphate balance. A key aspect of the new process instrumentation has been the development of an on-line analyser to monitor the total antimony concentration during zinc dust purification. As a result of changes made to the Zinc Plant in order to contain all effluent within the circuit, a problem developed with control of both the water and sulphate balance of the circuit. A new neutralisation plant to treat all cell house waste water so that it can be contained within the circuit has been developed and installed. In addition changes have been made to the existing circuit to control deliberately the circuit sulphate concentration by precipitation of sodium and potassium jarosite.

Jan 1, 1993

By Neill T. J, Howarth D. F, Malcolm J. McPhersqn

For many years Isa Mine has seen the need for a continuous mining machine which will economically cut hard rock. Tunnel borers are unsuitable due to the size and inflexibility of the machine and the shape of excavation mined. The design of roadheader type machines will not permit the use of the necessary cutting technology. in 1983 a joint project was undertaken by The Robbins Company and Mount Isa Mines Limited to develop and to trial a machine suitable for cutting hard rock in an operating mine. The project was based on the proven technology of raiseboring applied to horizontal development. The Mobile Miner was fabricated and trialled in a disused quarry in the U.S.A. during early 1984. Following these trials, the machine was transported to Mount Isa and commenced mining in September that year. The initial duty was to continue the development of a decline commenced by conventional mining for a conveyor system to serve the deeper southern areas of the 1100 copper orebody. This system will permit direct tipping of copper ore to a new crusher complex and conveying of the - crushed ore approximately 2 kilometres to the central hoisting shaft facilities. The Robbins Mobile Miner MM120-3001 uses a vertical rotating cutting wheel mounted on a horizontal swinging boom to excavate a nominally rectangular shaped heading. The cuttings are collected on an apron and conveyed back through the machine. The resulting excavation is smooth-walled with no blasting damage to the surrounding rock. This provides a safer working environment than does conventional drill and blast development mining. Ground support requirements are considerably reduced.

Jan 1, 1986

By May J. R

Exploration, including research, has fuelled the enormous expansion of the Australian mineral industry in the last three decades. Analysis of success and failure in exploration and research has therefore potentially powerful lessons and messages which may be used to influence the future shape and direction of the mineral industry. Research has been an integral part of organised corporate mineral exploration since its beginnings in Australia in the 1930s. In corporations, the activity generally called project generation or new project development is the main expression of exploration research but mostly it goes unidentified and poorly documented except perhaps when a successful discovery is made and reported on. The competitive nature of exploration means that extended and detailed analysis of corporate exploration research across the industry is impossible to achieve.

Jan 1, 1992

The development of the SECV brown coal open cut at Loy Yang will require depressurisation of aquifers both within and below the coal seam sequence in order to maintain open cut stability. Prediction of future open cut dewatering requirements at Loy Yang Open Cut and evaluation of the regional consequences of dewatering has required development of a detailed hydrogeological model of the Loy Yang area. The complex stratigraphy of the coal seam and aquifer/aquitard sequences at Loy Yang have been analysed and integrated with the hydrogeological concepts developed from regional groundwater studies to formulate a realistic hydrogeological model as a basis for finite-element flow modelling.

Jan 1, 1988