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By Kay JR

In 1984 a new Regional Geological Mapping Program (RGMP) was commenced by the Geological Survey of Queensland (GSQ); the new program was in response to the withdrawal of the Bureau of Mineral Resources from regional mapping. Areas for mapping were selected in northern and south-eastern Queensland on the basis of potential for mineral discoveries, level of company interest, inaccuracies in the first edition mapping and interests of other organisations (government and universities) in joint projects.Geological provinces of particular interest in northern Queensland are the Hodgkinson Basin, parts of the Georgetown Inlier not covered by earlier BMR-GSQ mapping, Broken River Embayment, Burdekin Basin, Lolworth-Ravenswood Block, Campwyn Block and Anakie Inlier. The 1:250,000 sheets covering these areas of interest are shown in Figure 1 including those already completed, those in progress and those planned for future investigation.A flow chart showing the various phases for RGMP projects is shown in Figure 2. Data collection has two facets: (i) field recording and (ii) office work including air photo interpretation, study of company reports, literature research, petrography and various laboratory studies. Two main strands of information collected are represented by a data base and compilation sheets. Compilation sheets are generally at 1:25,000 scale and are available for purchase. The current data base is very fragmentary and can be accessed only by direct contact with the relevant geologist or via written reports. A more accessible field data base is in the process of being introduced this year; this field data base (REGMAP) is based on standardised data recording and computer storage.

Jan 1, 1986

The problems of the as-built water supply system are discussed. Recent modifications to the collection dams and the water cleaning station using wedge wire screens to resolve these problems are outlined.

Jan 1, 1978

Mining software packages are used extensively in industry for resource estimation as well as for mine design and operation. Research undertaken in the W H Bryan Mining Geology Research Unit at the University of Queensland has shown that modifi

Jan 1, 1994

At 9.45 pm on Thursday, 12 July 1962 glass began to flow in an endless stream from a massive melting tank in a new Whangarei factory and a vital new industry was born û right on schedule. It wasn't good glass. It was ridged. It cracked. It rippled. It obstinately refused to emerge upstairs in the cutting room in one solid continuous sheet. But all through the night, drawing speeds were adjusted, temperatures changed. And on Friday morning, at 8:30, it finally came through as sheet û not perfect as yet, but sheet glass all the same. The rest is only a matter of time. Unfortunately, the buoyant enthusiasm displayed by the founders of the sheet glass industry in New Zealand, and the technical expertise of their European consultants, failed to bring the glass quality up to commercially acceptable standards and within six months, the company was in receivership. Taking over the role of producing New Zealand's sheet glass requirements, New Zealand Window Glass Company was formed as a partnership between two companies with long experience in sheet glass manufacture û Pilkington Brothers (NZ) Limited and Australian Consolidated Industries Limited. This paper sets out to identify the raw material requirements and controls necessary for the successful manufacture of sheet glass, and the availability and supply of suitable materials for use at Whangarei.

Jan 1, 1978

By P B. Hills, R J. Walton

Narrow vein tabular orebodies are prone to mining induced seismicity. The Tasmania Mine is a complex example of a seismically active tabular orebody, where the contrasting material properties of the host strata and of the orebody itself, serve to exacerbate the seismic response. Analysis of a continuous record of seismicity over a period of seven years has provided significant insight into the fundamental mechanics of the rock mass. Understanding seismicity to permit safe extraction of the orebody has been enhanced by instrumentation of rock mass behaviour in response to mining and mining induced seismicity. It is the purpose of this paper to explore that understanding in respect to the adoption of an alternative down-hole Avoca stoping method for use in particular circumstances.Intensive instrumentation of the Tasmania Mine over a period of four years has provided insight into the behaviour of the rock mass in response to extraction of the narrow vein orebody it encompasses. A range of instruments have been installed in clusters or single installations in order to measure changing stress conditions and the impact of those changes on the rock mass and the reinforcement system.Instruments are often installed in very close proximity to active production stoping. While it has been possible to observe the impact of the mining and mining induced seismicity at very close quarters, instruments installed in these locations are vulnerable to damage and consequently, the level of instrumentation is high. Instruments are continuously logged, typically on a six hourly basis coinciding with the end of regular blasting times. The response of the instrumentation to changed rock mass conditions is considered against the background of development and production blasting and against the seismic record to assess the viability of downhole Avoca stoping.CITATION:Hills, P B and Walton, R J, 2012. Continued observations of rock mass behaviour in response to stoping at the Tasmania mine, Beaconsfield, Tasmania, in Proceedings Narrow Vein Mining 2012 , pp 169-178 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Mar 26, 2012

Problems associated with gas management become more significant as exploitation of coal reserves in the Bowen Basin in Australia becomes deeper. At Oaky North mine, relocation of production from one area of the mine to another with a higher gas content required the use of pre-drainage, post drainage and inertisation techniques to enable production activities to continue largely uninterrupted. Innovative surface to inseam drilling techniques were developed for pre-drainage of reserves close to mine workings and have proven to be largely successful. The gas management techniques adopted and specific experience gained are discussed in this paper.

Jan 1, 2005

By Cleghorn JH

Underground mining operations on Kalgoorlie's Golden Mile were suspended in 1976, suffering the combined effects of low gold prices and grades. A subsequent substantial increase in the gold price led to the decision by Kalgoorlie Mining Associates to reopen their mines in 1979. The two shafts selected for access required excessive maintenance. The geological assessment and development parameters prescribed have been successfully used to establish reserves to maintain production at a 390 000 tonnes per annum rate. While ore reserve grade is being maintained from primary stoping sources, supplementary lower grade ore is drawn from remnant pillars and stopes at lower cost.Performance by the workforce has reached levels previously attained and a record tonnage was hoisted in the fourth year after recommencement.Keywords : Golden Mile lodes, geological research, payruns, cut and fill, mill holes, gold price, ore grade, amalgamation.

Jan 1, 1984

By McGuckin P. H

The Cadjebut orebody is a MississippiValleyType (MVT) zinc-lead deposit, and is located approximately 80 km southeast of Fitzroy Crossing in the Kimberley region of Western Australia. It is one of five zinc rich orebodies discovered by BHP Minerals in the region.The participation in the Cadjebut Joint Venture is BHP Minerals limited (Manager), 58 per cent and Billiton Australia Limited, 42 per cent.The mineralisation is contained in gently dipping dolomitised limestone sediments (part of the Lennard Shelf carbonate sequence) with an orebody width of between 60 and 120 m and a strike length of approximately 3 km. The deposit consists of two thin, stratabound shallow dipping orebodies, one overlying the other, to provide discrete but not independent mining areas. The orebody contains approximately 2.1 million tonnes of recoverable ore at an approximate grade of 12 per cent zinc and four per cent Lead.

Jan 1, 1992

 Increasing concern about the impact of alluvial mining discharges on the water quality of some West Coast rivers lead to a joint West Coast Gold Miners Associate, Trade and Industry funded study by Water Technology (NZ) Ltd. The objective of the study was to assess the treatability of West Coast alluvial gold mining discharges and to develop simple treatment systems which could be effectively adapted to a variety of sites in the region.   The approach was to apply standard water treatment techniques to field situations using low cost technology. Initially the various types of alluvial gold mining operations were identified then after preliminary site investigations and laboratory studies were carried out, site pilot plants were set up. The results of the trials particularly those using chemical aids were encouraging and it was found that chemical aid performance was largely dependent on the degree of mixing at and downstream of the chemical addition point. Design alterations to settling pond configurations in conjunction with optimised chemical addition yielded dramatic results in the form of reduced effluent turbidities.   A generalised approach to effluent treatment was developed and some of the specific 'mix and match' requirements were identified for different types of sites. The general conclusion is that improved physical treatment combined with good plant management and operation and (where necessary) chemical treatment, will produce water of acceptable discharge quality.

Jan 1, 1989

The King River Power Development on the West Coast of Tasmania has involved the storage of the waters of the King River in the new Lake Burbury and their diversion through a 7 km tunnel to a 144 MW power station. The last kilometre of this tunnel descends through 160 m under a ridge before emerging from the bank of the King River at the power station site. The decreasing cover over the tunnel as it approaches the power station meant that a steel lining was required in the last few hundred metres of the tunnel. This paper describes the geotechnical investigations which were carried out to establish the necessary length of the steel lining.

Jan 1, 1993

Swedish sulphide mining is presented. Dry filling is described. Fill properties with and without cement addings are dis- cussed in relation to various studies in la- boratory and in situ.

Jan 1, 1973

This paper describes the application of a three-dimensional finite element modelling tool to help assess the stability of a highwall at a Central Queensland mine following the weakening of its base due to highwall mining. With traditional stability assessment techniques, likely failure modes are identified on the basis of previous experience and structural, sedimentological and geomechanical data and a mechanistic analysis of these individual modes is performed. The value of the full three-dimensional model over these traditional techniques is that it provides a coherent approach to assessing highwall stability without the necessity of initially deciding upon the dominant failure mechanism and gives a useful adjunct to the traditional tools. The three-dimensional model assumes the rock mass is made of elasto-plastic blocks, incorporating possible planes of weakness, separated by near horizontal joints. The model includes the relaxation of stresses due to the excavation of the highwall and incorporates estimates of blast damage near the highwall surface

Jan 1, 1995

By Leach B. G

A geostatistical study was made of diamond drill hole intersections within 18CC stope block at the C.S.A. Mine, Cobar, N.S.W. The stope block is located in 18CC orebody which is a massive sulphide - multiple vein, Copper-Zinc type, lacking clear definition on gangue mineralogy, base-metal assays and total sulphide considerations. Of the variograms constructed for inter- section width and copper, lead and zinc grades and accumulations, only zinc displayed behaviour amenable to model fitting and kriging procedures. Zinc grades were calcu- lated for sub-blocks comprising the total stope block and comparison with equivalent grades determined by traditional methods showed them to be generally less extreme in the highest and lowest grade sub-blocks. The total-block grades derived by the two methods were almost the same. It is suggested that the failure of copper to show variogram continuity might reflect the difficulty in defining the actual 18CC orebody, a proposition which is supported by the poor continuity in the variogram of horizontal width. In the case of lead the poor continuity may be due to the frequent manner of occurrence of galena as coarse grained patches of limited extent. The results of the study, did not provide a convincing reason to depart from the traditi- onal methods of grade estimation at the C.S.A. Mine.

Jan 1, 1979

The development of reliable and accurate solution sampling systems plus on-line atomic absorption spectrophotometers and voltammetric analysers at Pasminco Metals - EZ's (PMEZ) zinc refinery at Hobart, Tasmania, has led to extensive implementation of On-Stream Analysis (OSA) throughout the hydrometallurgical circuit. These systems complement industrial autotitrator and colorimetric analysers and with the comprehensive use of a powerful integrated Distributed Control System (DCS), provide extensive monitoring and control of all the important in solution' parameters for the plant. Samples can be left unaltered, or filtered or settled, to remove solids. They are then precision diluted and pneumatically transported to analyser shelters, where they are analysed for zinc, acid, copper, cadmium, lead, antimony, cobalt, nickel, mercury and ferrous, ferric and/or total iron. The range of analyses depends on the sample itself. The results are used for feed forward and/or feedback control of reagents where possible, or simple trend monitoring and out-of-specification alarming when closed loop control is not practical. The overall system reliability and accuracy is such that many daily composite plant samples are no longer analysed off-line. Operator sampling has also been reduced, and in two places, autotitrators with automatic sample pre-treatment have been installed for preparing and analysing samples collected by operators.

Jan 1, 1993

Trucks are the primary means of bulk material transport in Open Pit hard rock mines worldwide. They are considered to be the most- flexible system available. The large number of trucks used in some mines provides flexibility. Spare units allow for the reduced availability of the single units. Trucks have however very poor energy efficiency. Only 40% of the consumed energy is for transport of the payload, the remaining energy is required to move the dead load of the trucks. With the increase in cost, pressure, mine operators are now looking for alternative methods to make their operation more economical. Energy conservation and increasing haulage distances and uphill haulage are major factors in many well established operations. New methods have already proven themselves as more economical alternatives. Belt conveyors are an alternative means of transport with much higher energy efficiency. They use up to 80% of the consumed energy for transportation of the payload. Energy costs for conveyors are 30% of the energy costs for trucks on level transport and as little as 15% for elevating payloads. Belt conveyors require much fear spare parts and wear components than trucks. A factor of one to two times applies for level transport and ten to twenty times for uphill transport.

Jan 1, 1986

It is always difficult to sum up an open forum adequately and instantaneously, so, with the privilege of hindsight, and also with some time to reflect, I am exercising the Chairman's prerogative to put together my view of the overall conclusions. Hopefully, these may provide a focus for each Institute to formulate its own programme with respect to mineral industry education. First, in answer to the question, "Should there be Schools of Mines?", there was a very clear 'yes'. However, I reiterate what I said in the introduction to this forum, specific professional education for the mineral industry exists only because the mineral industry sees a need and wants it. If the mineral industry should decide that it does not need professionals with specific mineral industry training, then such training will cease to exist. As alluded by Dr Hackett, if such training ceases to exist, one must then question the need for Institutes of Mining and Metallurgy. Now, there's some food for thought! Specialist schools of mines (metallurgy and geology) can only exist in an environment of genuine interaction with, and support by, industry. For their part, schools of mines, used here in a generic sense, require leadership that is strong but responsive to industry needs. It is the leader that puts his stamp on a school, and, to a large extent, determines whether that school is 'good' or only 'mediocre'.

Jan 1, 1986

A simulation of the fluid flow, minera- logical and chemical aspects of in situ leaching is being developed for application to the recovery of metals from unbroken, naturally jointed rock. The fluid flow aspect has been developed. The rock is assumed to have a double-fracture property. A major joint set is responsible for bulk flow of solution, while a minor joint set, intersecting with the major set, allows the solution to contact the reactive minerals. The two-dimensional fluid flow through the major joint set is analysed by a streamline model for a particular well pattern. The other important components of the model are described briefly.

Jan 1, 1984

By He F, Zhu D

How to monitor and control the support and surrounding strata system on a longwall face effectively is one of the major research problems in ground control. Based on observations on movements of the support and surrounding strata of face No. 2703 of Dongpang colliery, the relationship between the downtime related to support and surrounding strata and other influential factors is analysed systematically in this paper. Monitoring indices and control measures are then determined by taking corresponding downtime as an objective function. When the monitoring method, developed from the above findings, was used on face No. 2703, the downtime due to support and surrounding strata was remarkably reduced, and the face advanced Normally.

Jan 1, 1992

By Lu T. K

A new type of rockbolting system, the self drilling rockbolt, has been studied to develop a 'single pass' bolt for use in rockbolt installation in underground engineering. This single pass bolt forms the basis of a Rapid Face Bolting system which will reduce the amount of time spent in securing a roof during the operation of a continuous miner in the development of a panel.The installation efficiency and anchorage tests were performed in the laboratory on the self drilling bolt and the traditional resin anchorage. bolt. The results of both bolts are cmmnared.

Jan 1, 1993

Over the longer term, the adoption of new technology is an essential component in the endless tasks of reducing mining costs, improving safety and improving environmental standards. However the choice of which of the many available new technologies to adopt and which not to adopt is not easy and the price of mistakes can be very high. The most important issue for mine developers faced with making such choices is knowing whether or not a new technology has been developed to the stage where the timing is right for its adoption. A system for categorising new mining technologies is provided. It provides a basis for more easily reaching common understandings about various new technologies and the background information supplied provides an understanding of what it takes to get new technologies to the proven stage and the risks of never getting there. Wherever possible, new full-scale mine developments should not rely on unproven technologies. Approaches to handling situations where a proposed new mine development is not feasible on the basis of proven technologies are also provided. If any commitment to the use of unproven technologies is made, a guarantee of high quality development support from the supplier of that technology is essential. Several case studies of successful and unsuccessful new technology development programs at BHP are Provided.

Jan 1, 1997