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Address by the President (Mr B T Loton) in presenting the Institute medal for 1981 to Charles Wooller Marshall AO. Address by Charles Wooller Marshall AO after accepting the medal.

Jan 1, 1982

By Denby B, Miles N. J

The underlying theory behind the construction of an on-line size analysis system is described together with an introduction to the Artificial Intelligent techniques that it is founded on. Previous systems based on more traditional technology such as edge detection and dilation algorithms have been restricted by the significant processing power they require, this has resulted in the production of systems with either reduced functionality or severe hardware requirements. A neural network approach offered a new perspective to the problem of size analysis; the ability of a network to learn and recognise subtle patterns in training data before on-line processing is initiated opened up the possibility for the production of a fully functioning practical system. The format of the training data had to be carefully analysed prior to its implementation in a neural network as the capability of a neural network solution depends as much upon a suitable data preparation as it does on the system architecture. To facilitate experimentation with various profile quantification techniques such as fourier and fractal analysis an Image Profile Analysis System was constructed (IPAS) in software on a personal computer. The IPAS system was produced with the aim of pre-processing image data to create data sets for experimenting with external neural network packages. The system allows the analysis of both real images obtained by image capture and simulated images created by an in-built in simulator. A measurement comparison scheme is also included together with a case study concerned with the frequency analysis of simulated images. The power of neural networks combined with the data compression provided by profiling removes the need for direct measurement of individual particles. This has obvious implications on the level of hardware necessary, and ultimately the expense of a stand alone system. The extrusive nature of data collection via an image analysis system will also permit simple installation of a shipped system; eliminating any requirement for interference with existing machinery.

Jan 1, 1995

Mining companies often view water quality as an environmental issue. The importance of water quality as a production related issue in mineral beneficiation is greatly underestimated at many mineral processing operations. While most mine sites have comprehensive water balance data for water quantity, the information regarding the quality of water supplies available on site is limited, inadequate or non-existent. The seasonal variations in process water quality and changes in the composition of various water streams are not known. Despite the fact that water represents about 80 to 90 per cent of the volume of mineral pulp processed in a flotation plant, the influence of process water composition on flotation performance is often poorly understood. The process water used at mineral processing operations is made up from a number of available water sources, which can be classified as recycled water streams or make-up waters. The recycled water streams are commonly the tailings and concentrate thickener overflows, filtrate from the concentrate filtration plant and tailings dam return water. Make-up waters can originate from a variety of sources: surface waters (rivers, lakes, reservoirs, dams), groundwater (wells and springs), mains water (potable water), treated and untreated sewage waters and industrial effluents. Mineral processing plants are increasingly recycling water to reduce demand for fresh water and minimise the discharge of wastewater to the environment. However, increasing water recycling can have adverse effects on process water quality and ultimately on the performance of mineral separation processes. The main reasons for reduced plant performance due to water recycling are the accumulation of organic and inorganic compounds in the process water and increased microbiological activities. Other detrimental effects of water recycling can be increased reagent consumption and inefficient dewatering of tailings and concentrates. Recycling of water also tends to accumulate very fine suspended particles. Excessive amounts of slimes in the process water can also have an adverse effect on mineral beneficiation processes. The main constituents of process water are dissolved gases (oxygen, nitrogen, carbon dioxide), colloidal and suspended solids of inorganic and organic nature (including micro-organisms: dead or alive), dissolved organics (natural organic matter, residual reagents, reaction and decomposition by-products of chemical reagents, impurities in the reagents and metabolites originating from microbiological activities) and inorganic compounds (acids, alkalis, inorganic salts, metal ions, anions and heavy metals). Inputs to the chemical composition of process waters are: dissolution of soluble mineral phases present in the ore, surface oxidation followed by dissolution of mineral particles during grinding and mineral processing, the chemical composition of various make-up waters and recycled water streams, and reagent additions during mineral processing. The beneficial or detrimental impact of process water quality on flotation performance can be attributed to a number of subprocesses: adsorption and/or precipitation of inorganic and organic species present in the process water onto the surface of mineral particles, chemical reactions between process water constituents and the chemical species present on the surface of mineral particles and interactions between the chemical and microbiological species present in the process water and the various reagent species added in solution during mineral processing. Dissolved chemical species such as calcium, magnesium, iron, copper, lead, zinc, nickel, sulfates, phosphates and carbonates can have a strong effect on the electrokinetic properties of oxide and sulfide minerals, at certain pH ranges. Several reactions can occur at the solid-liquid interface that can play an important role in determining surface adsorption of reagents. Solid-liquid interfacial properties of mineral particles can be significantly affected by the conformation of adsorbed and precipitated reagent layers, which in turn are determined by solution chemistry. The chemical and microbiological constituents of process water can have a significant effect on liquid-gas interfacial properties and have a strong influence on froth height, strength and stability during flotation. Water chemistry can play an important role in determining the interactions between minerals present in the ore and the chemical reagents added in the mineral processing plant by altering the reagent-solution and mineral-solution equilibria. These interactions can include dissolution, micellisation and precipitation of reagents, dissolution of minerals contained in the ore followed by hydrolysis, complexation, adsorption and precipitation of dissolved chemical species and reactions between dissolved ions and various reagent species present in solution. All of the above mentioned subprocesses can ultimately have a significant effect on the efficiency of mineral processing operations. In this presentation, a systematic approach for assessing the composition of water supplies available at the mine sites and for investigating the influence of process water quality on the efficiency of mineral processing operations will be discussed. The consequences of mixing different quality water streams to produce the required volumes of process water for some flotation plants will be highlighted. To substantiate the water quality issues described in this paper some examples are given from a metalliferous processing perspective. However, the topics described in the paper are not only relevant to metalliferous processing but to all other type of mineral processing operations as well. In fact the principles described in this paper have also been successfully applied to the coal flotation industry.

Jan 1, 2006

By Callcott R

Prediction of raw coal size distributions and those generated by processing are examined using spreadsheets and the matrix analysis of breakage processes. Run of mine coal size distributions are predicted from the lithotype properties using a

Jan 1, 1998

During the period May to July 2003, East Mine overcored and recovered from goaf edges a total of 55 1.8 metre CVX grade bolts to analyse installation quality. Some 95 per cent of the pneumatically (hand-held Gophers) installed bolts show gloving, with 75 per cent showing gloving of at least one-third of the effective bolt length. Hydraulically installed (continuous miner-mounted bolting rigs) bolts show in some areas less gloving but do have significant unencapsulation lengths. Trials of newly developed bolt end profiles show considerable improvements in eliminating gloving but do show variable and unacceptable variations of unencapsulation.

Jan 1, 2003

By Mandzic E. H

The Dome Mine of Timmins Mining company is located in South Porcupine, N.W. Ontario. The orebody being mined partially lies in the No. 3 shaft pillar. Stability analysis has been carried out to establish the influence of nearby mining on ground movement in the shaft vicinity. Mathematical modelling of shaft displacement has been done for stope layout at depths from 180-210 m and distances of 10-50 m from the shaft. Analysis indicated that ground displacement around the shaft is below 1 mm/m and one third less for cut and fill than in the case of open stope mining. The result of the investigation was later confirmed by cut and fill mining of this orebody.

Jan 1, 1986

By M A. Ward

On 23 May 1977 the Hon Mr George Gair announced an amalgamation of the present Ministry of Energy Resources, the New Zealand Electricity Department and the Mines Department. Hopefully it will prove to be the solution of many national problems in energy planning and policy making, in energy distribution and use, and energy discovery and production. The name of this new giant is the Ministry of Energy which gives a firm indication of its future direction. For those amongst us involved with mineral energy resources the establishment of this new department must be encouraging. For those amongst us who are involved in non-energy side of the mineral industry it is the very opposite. The loss of the Mines Department a year short of its centenary is a loss for the mineral industry without a doubt - but how much of a loss?

Jan 1, 1977

By Cresswell G. M

The international coal industry is becoming increasingly aware of the economic impact of coal dewatering in terms of plant yield limitations, attainment of product specifications and freight costs. This paper examines the current position of dewatering within coal process plant design and reviews equipment developments over the past decade.

Jan 1, 1993

In the last two decades, equipment used in the coal mining operations has become much more sophisticated. The way that work is organised and performed in the industry has also changed significantly. Changes in equipment specification or procedures inevitably means that the risk associated with that equipment or procedure also changes. In an attempt to address this the Joint Coal Board Occupational Health and Safety Trust (JCB) commissioned the University of New South Wales Mining Research Centre and Mine Site Technologies to perform a feasibility study into the development and deployment of Virtual Reality (VR) based training simulators in the New South Wales coal industry. The main aims of the study were to identify, the key providers of VR Technology, the VR options available to the JCB and the information that would need to be included in any simulator. It was anticipated that a critical assessment of these components would produce a format for a cost effective, state of the art simulator that could be readily accessed by all mines. The expectations of the feasibility study were that VR should offer three-dimensional (3D) simulations that are interactive, high-resolution models of real environments based on best practice Safety Management Plans. It was anticipated that the simulations would allow trainees to experience the consequences of poor decision-making and allow them to learn from their mistakes in a safe and forgiving environment. It was envisaged that such simulators would become an addition to the existing training methods used in the industry.

Jan 1, 2003

While reaction to immediate demands may be required from time to time, the principal concerns of a Geological 'Survey should be proaction, with respect to the systematic production of maps, reports and data in order to meet exploration needs in the longer term, and interaction, which involves a complex matrix of relationships - firstly within the Department between disciplines and at various levels of responsibility, secondly with the exploration industry, thirdly with Commonwealth authorities particularly the Bureau of Mineral Resources (BMR), and fourthly with university researchers in related fields.

Jan 1, 1987

The Professional Standards Act responds to the growing problem of professional liability by introducing a mechanism whereby professional associations can have schemes approved. Those schemes include a cap on liability; a requirement for compulsory insurance; the development of risk management strategies; and the establishment of a complaints and disciplinary system. The Act is also designed to support and develop the concept of self-regulation by the members of occupational associations who provide services to the community by providing them with those tools. It implicitly accepts that self-regulation is preferable to statutory regulation and that self-regulation serves the interest of the community and of the providers of services. The Act arose from a review of professional liability commenced in 1988. The Attorney General's Department produced an Issues Paper, released in September 1989, which outlined in detail the extent of the problem. This was widely circulated and an extensive number of comment were received.

Jan 1, 1995

Brisbane based and listed on the ASX, Eastern Corp is pursuing the development of coal projects in New Zealand. There are various reasons why New Zealand coals are of interest û substantial resources, stable political/economic environment, close to Asian markets. In just over 12 months, Eastern has secured an operating coal mine (Cascade) and a prospective exploration area (Whareatea West), both on the Denniston plateau region, on the south islandÆs west coast. A key focus of activities is the development of relationships with key stakeholders and the promotion of the local economy.   Certain barriers may exist to the entrance by foreign companies into the New Zealand coal mining sector. These include geological challenges provided by the heavy faulting of the coals, port and rail infrastructure constraints, and the ægreenÆ factor.

Jan 1, 2005

The introduction refers to observations made in the early days of the Nationalisation of the Coal Industry in the United Kingdom, indentifying the underground transportation problems. Statistical information is presented, highlighting the considerable developments which have been made in recent years with an evaluation of the manpower and cost involvement.

Jan 1, 1985

By Bhaskara Sarma P V R

Solvent extraction of cobalt from an ammoniacal ammonium sulphate medium was carried out using Di(2-Ethyl Hexyl) phosphoric acid in kerosene as diluent. The effect of ammonium chloride and ammonium sulphate on the extraction efficiency was studied. The extracted species in the ammonium chloride and sulphate systems were CoAz2HA.NH4CI and CoA3.HA.2(NH4)2SO4, respectively. Ammonia scrubbing and cobalt stripping studies were carried out from loaded and ammonia free organic Respectively.

Jan 1, 1992

By P J Savory

Ranger is a uranium mining operation located within one of the most environmentally sensitive regions of Australia. Geology has played an important role in mine planning, operations and rehabilitation since discovery of the deposits 25 years ago. The Ranger orebodies have a reserve total of 166 300 tonnes of U308 including 90 400 tonnes of U308 at North Ranger. At current milling rates these reserves give a mine life greater than 40 years. The uranium is hosted in Lower Proterozoic rocks of the Cahill I ormation and is associated with strong chlorite alteration. In pit grade control involves the use of calibrated probes and a radiometric truck discriminator allowing fast, accurate grade determination of material. Ore is defined at a cut-off grade of 0.2 per cent U308. Mineralised material is defined by the Uranium Mining (Environmental Control) Act 1979 (UMEC Act) at a grade of 0.02 per cent U30s. Natural water levels in the #1 Pit area vary as much as 7.5 metres between wet and dry seasons. Ground water inflow into the pit during the dry season is 600 m3/day. No significant slope failures have occurred in the pit. The environmental impact of mining operations is constantly monitored. Rehabilitation of non-mineralised stockpiles is ongoing. This paper discusses the interaction between geology, hydrogeology, rock mechanics and grade control with the present mining operation.

Jan 1, 1994

The Government Mining Engineer of South Africa has decided to legislate that Self Contained Self Rescuers (S.C.S.R.) become a mandatory piece of equipment for all those persons proceeding underground. It is envisaged that: * employees in underground coal mines will be fully equipped with S.C.S.R.s during 1988; * those persons employed in gold mines during 1988/89; and * personnel in all other mines by the end of 1990. It is the intention of this paper to discuss the introduction of these auxiliary life support systems, and to give an update on current market developments.

Jan 1, 1988

Successful management is ultimately measured by return on shareholders' funds. This is the inescapable and inexorable discipline that ultimately rules every investment. Shareholders today are predominantly, and increasingly, the superannuation funds and insurance funds of almost all of us. We have already reached the situation in Australian investment history in which the best interests of employees can be very directly identified with the best interests of the owners of the capital invested.

Jan 1, 1992

By C Donnelly

Redpath Australia is using a unique mining method for the Australian underground coal industry at Kestrel Mine Extension in the Bowen Basin, Central Queensland.The project involves completing two separate drifts from the surface for access to the German Creek Coal Seam located approximately 230 m below the existing surface. The scope of work is primarily the construction of two drifts; the first is 1577 m at 1 in 6 gradient and the second 1874 m at 1 in 8 gradient. Each drift has been developed by a Mitsui S200 roadheader with modifications to allow for a continuous tunnelling/mining cycle operation. A shotcrete boom has been fitted to the left hand side of the machine with the operators console located at ground level. Another operators console is elevated on the right hand side of the machine to allow operation of the rotary drill boom which is mounted on a slide rail to allow flexibility of positioning depending on the stage of the cycle. In support of the roadheader activities, an integrated conveyor system mounted on a sliding floor arrangement is able to be advanced as the mining face progresses. This sliding floor consists of four 1.5 m × 6 m sections that utilise hydraulic rams to ‘walk’ inbye, allowing room for installation of precast concrete floor panels for final floor completion. This method borrows from the tunnelling and construction industries to eliminate place-change delays in the mining cycle by enabling complete ground support installation without retreat of the primary development machine from the face. The aim is to reduce the project duration with the completion of final floor and services to within 30 m of the operating face as it advances.

Mar 21, 2011

During mapping in the Bijerkerno area (Fig. 1), well-preserved sedimentary structures were found at three separate localities. The structures are of four varieties, which are 1. small-scale cross-bedding (Fig. 2),2. convolute bedding (Fig. 3),3. minor scour and fill (Fig. 4), and4. flame structures.Ripple-marking is also doubtfully present.These structures are best preserved in what was...

Jan 1, 1971

By Campbell D. L, Nutt C. J

The Delta two-degree quadrangle is located in west-central Utah, in the eastern Basin and Range physiographic province but near the intersection of the Basin and Range, Rocky Mountain, and Colorado Plateau provinces (Fig. 1). The quadrangle lies in the region of interior drainage that includes western Utah and most of Nevada, and, like the rest of that province, it has an arid climate. This work is part of the United States Geological Survey's ongoing CUSMAP (Conterminous United States Mineral Assessment Program) project in the Delta quadrangle. Trace-element geochemical data presented here includes information from approximately 600 heavy- mineral-concentrate and 2500 rock sample sites from throughout the Delta quadrangle.

Jan 1, 1988