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By R M. Anderson, S P. Pigdon

The production of stabilised backfill at mine sites commonly uses Portland cement as the binder. Calcined gypsum has cementing properties and is cheaper to produce than cement. This paper discusses the strength of fills stabilised with calcined gypsum. Laboratory tests were carried out on specimens prepared from tailings obtained from four different sites to allow for the wide variety of tailings found in practice. The results show that the gypsum-based fills can achieve a strength of 1 MPa using around two and a half to four times the corresponding amount of cement.

Jan 1, 1998

By P A Ferenczi

The Proterozoic iron oxide related Au-Cu-Bi (Tenant Creek style') deposits at Tennant Creek can be classified as syntectonic polymetallic hydrothermal replacement type mineralisation. These deposits have characteristics in common with a number of other Proterozoic iron oxide (Cu-U-Au-REE) hosted deposits in regions which include Southeast Missouri, USA; the Kiruna district, Sweden; the Great Bear Magmatic Zone, Canada; the Stuart Shelf, South Australia; and the Wemecke Mountains, Canada. Similarities between these and Tennant Creek style deposits include: 1. Tectonic Setting: Formed at shallow crustal levels (

Jan 1, 1994

By Miskelly N

Construction of the Ranger uranium project located 230 kiss east of Darwin in the Northern Territory commenced in January 1979. Energy Resources of Australia Ltd (ERA) was incorporated in February 1980 to acquire all the rights in the project. The total cost to ERA of these rights was $407 million, made up of $125 million in cash to the Federal Govern- ment and the issue of 125 million $1.00 shares at par, plus a payment of $16 million in cash to each of Peko-Wallsend Ltd (Peko) and EZ Industries Ltd (EZ).

Jan 1, 1983

Samples weighing O·25 g are fused with 1 g potassium hydrogen sulphate, leached with 5 ml. of hydrochloric acid, and then diluted with another 5 ml. of acid. After settling, an aliquot of the clear solution is reduced with stannous chloride, and then a zinc dithiol solution is added to form a coloured tungsten complex which is extracted with petroleum spirit for comparison with standards.Concentrations down to 4 p.p.m. may be analysed at a rate of 100 determinations per man-day of 8 hr.

Jan 1, 1970

R F Johnston 1 ABSTRACT The possibilities for bacterial leaching of refractory gold ores found in the Central Victorian region of Australia are examined. The behaviour of bacteria, especially 77iobacillus ferroaridans is outlined and the effects of these when they are exposed to pyrite, arsenopyrite and stibnite are examined. The factors which are particular to Central Victoria are outlined and the possibility of adapting a bacterial culture to suit the conditions is discussed. It is concluded that a bacterial leaching system is a feasible proposition and that it could enhance leaching rates and yields.

Jan 1, 1994

By Horiszt G

his report is going to point to that the effect of the mining dewatering on the area of Transdanubian Mountain Range has reached a phase when the cost of dewatering and providing damages can seriously jeopardize a profitable mining operation. Up to 60s the interest of mining had been dominant only, but since the begining of 80s the conceptions of industrial development and the value of enviroment protection have been changed. The natural karstwater balance of the TMR can be presented (Figure Land 2.) and the present situation of it points to that the descharge has exceeded the reacharge in 50 %. During the past 10 years the decreasing of the stored karstic water resourches was 1.1 km . The decreasing of the spring yields reached 80-82 % of the natural ones. (Figure 3-4.). Conservation of the present discharge may lead up to the totaly drain of the karstwater regime. A computer aid control system had been to develop by the bauxite mining and using of it the yield of dewatering decreased and a moderate rising of the water table has started since 1986. A recunstruction was made at the biggest thermal-medicinal lake its springs have had their source in 40 meter depth inside a spring cave at the bottom of the lake. Earlier the spring yield decreased due to the dewatering activity of mines. As a result of using of the CAC system and the providing works at the thermal sprino,the karstwater balance has got in the state of equilibrum, the first cost was decreased and spring yield was increased and the enviromental limits were adverted from the way of mining.

Jan 1, 1988

The purpose of this paper is to present a detailed account of the development of the Blasthole Diamond Drilling method of stoping now used at the property of Big Bell Mines Limited, in Western Australia.The ore body is one of the large low grade gold deposits of this State, being a continuous lens 1,850 ft. long and ranging in width from 15 ft. at the ends to 120 ft. at the widest part, the average width being 59 ft. It was first worked in 1913 by a local syndicate, and up to 1924, when operations ceased, 64,448 tons of 3.4 dwt. ore were mined from a shallow open cut. Between 1928 and 1932, 15 deep diamond drill holes were put down to test the ore body at vertical depths ranging from 100 to 700 ft. On the information gained from these drill holes, Premier Gold Mining Co. Ltd. began underground explQration. A level was driven at a depth of 253 ft. and crosscuts put out to the full width of the, orebody at intervals of 100 ft. along the strike, all ore broken being put through a sampling plant. On completion of this sampling,' Big Bell Mines Limited was formed as the operating company, and a plant with a capacity of 1,000 long tons per day was erected and mining and milling operations were commenced in 1937. Ore was first mined from glory hole stopes, 65 ft. long, separated by 35 ft. pillars, by benching using conventional steel with changes up to 20 ft., all broken ore being hauled to the main shaft on the...

Jan 1, 1948

The common notion that the Box Hole Bore mineralization represents a variant of the Mississippi Valley type, has not been supported by the present investigation. Most of the common characteristics of Mississippi Valley type, namely 1. saturated saline brines; 2. low temperature domain; 3. mineralization in intraformational breccias and collapsed anticlinal structures; 4. hydrocarbon-rich or foetid carbonates, and 5. very simple geochemistry seem not to be applicable. The Box Hole Bore mineralization features: 1. moderately saline brines (18% NaCl); 2. very high temperature (495¦-520¦C) and low density brines, of critical vapour:water ratio and low pressure of formation (700 bars); 3. mineralization confined by faults and ex- tending laterally into carbonates of high pore volume such as stromatolitic dolo- mites; 4. ore environment characterized by oxidizing conditions, such as ferruginous carbonate and silica sands of high energy environment (heavy mineral banding) and 5. more complex geochemistry than is normal for Mississippi Valley type deposits (copper sulphosalts, and appreciable silver content). Additionally, the ore has un- usual textures formed by the replacement of carbonates and barite by large idiomorphic galena crystals. The pressure and temperature domains of the Box Hole Bore mineralization indicate post- Devonian emplacement and local high heat flow, possibly related to the Alice Springs Orogeny. Because of high lead and zinc trace element con- tents (100-600 ppm) of the carbonates, even out- side mineralized areas, it is possible that the mineralizing fluids have derived their metal con- tent from a local source, possibly aided by evap- oritic concentrations of the tidal to supratidal sequences. The new model for Box Hole Bore gives treater importance to the confining faults.

Jan 1, 1984

By Juniper LA

ERM Consultants Pty Ltd was established in 1980 for the purpose of introducing a disciplined coal technology and power station planning service, to support Australia's efforts in establishing a major export steaming coal industry. At that time, major coal exploration programs were mounted on more than 50 potential export coal deposits with proven open-cut reserves to export 200 Mt/a of coal. The fact that Australia achieved an export trade of only 30 Mt/a, equivalent to the energy requirements for a population of around 5 million people, illustrates the very small achievement to date. The main reasons for this small export steaming coal growth have been: 1. Failure to convince potential overseas coal buyers of the benefits of coal-fired power generation, and the ability of proper power station design to overcome environmental problems, and achieve reliable operation and long life when burning Australian coals. 2. Failure to promote Australian power engineers to advise on the use of Australian coals, resulting in Northern Hemisphere power station experience dominating in market countries. 3. Failure of governments to draw on privately practising Australian power engineers and coal technologists in technical workshops, presentations and assistance to overseas countries, to ensure that personnel whose business it was to serve the follow-on needs of countries were readily available. The result of these failures has been that: 1. Only a fraction of prospective overseas coal-fired power projects have proceeded. 2. Australia has had no influence in the design of overseas power stations to ensure that potential customers would be confident that Australian coals could be reliably burnt in their boilers.

Jan 1, 1987

By Binns MJ

Gold/silver orebodies of the Golden Plateau deposit, Cracow, Central Queensland, are currently being exploited by the Cracow Mining Venture. A geostatistical block model has been prepared to assist with long term mine planning. The Golden Plateau orebody, of inferred epithermal origin, is a multiply brecciated, silicified fault complex containing irregular, tabular and pipe- like oreshoots. Historically the lode has been stoped and open cut over a strike length of 750 metres at widths of up to 15 metres and to a depth of 250 metres. The Golden Plateau mine produced 1.55 million tonnes of ore at an average grade of 12 g/t Au and 13.5 g/t Ag over a 42 year period. In the preparation of the reserve model much reliance has been placed on recent diamond and reverse circulation drilling (71 holes in total). However a significant volume of data has been derived from historical level assays and underground diamond drilling. Over 3,000 level assays and 50 underground drill holes contributed to the database. Similar lognormal populations were observed for 1 metre composite grades from each major drilling campaign once corrections were made for core loss. Cumulative frequency plots revealed only one outlier which was cut to the population line. The population statistics from the historical level assays showed a significant difference from those derived from the drill hole composites. Level assay populations were cut to local drill hole populations before incorporation into the ore reserve model. The resulting data has yielded interpretable variograms, the parameters of which have been applied to the preparation of a kriged block model of the deposit.

Jan 1, 1987

Comminution of solids is surely one of the oldest technologies which even in this day and age of DNAs, chips and space exploration continues to challenge our scientific acumen and engineering ingenuity. In essence, this challenge is two-fold. One, as much as three to four per cent of all electric power generated world-wide is consumed in crushing and grinding primarily because the utilisation of energy is woefully poor. Studies have shown that the efficiency of mechanical size reduction processes is of the order of 1.5 to 12 per cent only (Schoenert 1986). Two, with the grinding technologies available to us, we have, at best, inadequate and, at worst, almost negligible control over the shape of the comminuted particles, size dispersion of the ground mass, and the sharpness of mineral liberation. Low energy efficiency and lack of control in the sense mentioned above have far-reaching implications for resource conservation, performance of down stream unit operations, and damage to the environment. Our problem is in fact central to the mineral-energy resources triangle shown in Figure 1 which depicts the close interrelationships among mineral resources which are becoming poorer in content and more complex in mineralogy each day, energy resources which are depleting rapidly without any viable alternate on the horizon, and environmental concerns which can no longer be ignored. It is evident that any improvement in the efficiency of the comminution process impacts directly on the control of environmental damage, conservation of energy and the economics of the operation. These concerns have special relevance for the processing of non-ferrous ores.

Jan 1, 1992

The Maddingley brown coal seam at Bacchus Marsh, where mined and bored, tends on the whole to a higher content of volatile matter than the Latrobe Valley brown coals, and this masks the presence of lignitic or earthy coal bands in the bore core analyses. Visits to the Lucifer Open Cut, at Bacchus Marsh, during 1948, revealed, however, a banded condition in the coal seam, as shown in Fig. 1. This banding showed in a face that had been exposed for a considerable period of time, permitting partial drying out and oxidation of the surface coal. The bands consist of different coal types, ,comparable with those found in the Yallournand Latrobe brown coal seams(l).The' light coloured bands in Fig. 1 consist of a buff to light-brown earthy coal of low specific gravity, that closely resembles the pollen coal, that occurs, as similar thin bands in the Yallourn and Latrobe seams. The 40 ft. of coal above the uppermost of these light coloured bands dries out on exposure to a black, closely cracked surface, composed of small dice-like fragments of a lustrous vitrain-like substance, and in every respect resembles the lignitic coal bands of the Yallourn and Latrobe seams.The coal between and below the light-coloured bands develops fewer and more widely spaced shrinkage cracks on drying out, and remains brown in colour and earthy in appearance, resembling the earthy coal of the Yallourn and Latrobe seams.Representative samples were cut of these coals, taking care to exclude surface coal, and analyses were made of them by the Metropolitan Gas Company, through the kindness of Dr. R. S. Andrews, Chief Chemist to the Company...

Jan 1, 1948

By Konishi Y, Morioka Y, Okabe K

A part of the results of dissection survey of Chiba No.1 blast furnace, Kawasaki Steel Corporat- ion, is presented. Distributions of coke size and of slag and metal holdup are shown in the region of the dropping zone. A similar relation to the irri- gated packed bed is obtained. The distribution of coke size, coke temperature and liquid holdup are measured in and around the raceway. The shape of raceway in the horizontal and vertical sections indicates that each raceway worked individually. Liquid flow in the dropping zone and around the raceway on the basis of holdup measurements is Discussed.

Jan 1, 1981

By Phipps P. J

The rate of precipitation of ferric iron as ammonium jarosite, NH4.Fe3(SO4)2(0H)6 from acidic solutions near 100¦C, was found to increase with weight of jarosite seed crystals, and with concentration of ammonium ion, but to decrease with increasing acidity. The particle size of the product crystals was larger at low sulphate concentrations and at high ammonium concentrations. Particles appeared to be agglomerates, with diameters ranging from 0.5 up to 25 um, and composed of individual crystals of diameters ranging from 2 um apparently down to 0.1 um or Lass

Jan 1, 1977

In any open pit mine some slope instability may be expected. This can range from small scale sliding on individual benches to large scale overall slope failure. This paper presents two case histories which illustrate how mining has successfully continued despite major pit instability. The common threads in each of these are listed below. 1. The recognition of the type and nature of movement (either regressive or progressive). 2. The successful application of simple monitoring techniques to minimise the potential impact on the mining operation, and 3. The management of the waste and ore excavation to avoid potentially damaging and costly situations.

Jan 1, 1986

Queensland hosts vast deposits of brown and black coal, significant accumulations ranging in age from Permian to early Tertiary. The great diversity of coal resources in the State to some extent reflects the proximity of Queensland to plate-marginal tectonic processes through much of the Phanerozoic eon. Coal is contained within sedimentary basin fills of four fundamental types; 1. extensional, 2. foreland, 3. strike-slip, and 4. intracratonic. Thick (10 m+) though laterally restricted coal bodies are characteristic of extensional and strike-slip basins, whereas coals of more modest thickness but much greater lateral extent are typical of foreland and intracratonic basins.

Jan 1, 1991

The Olympic Dam copper-uranium-gold-silver deposit, located approximately 520 km north-northwest of Adelaide, South Australia (Figure 1) was discovered in 1975 by Western Mining Corporation. A joint venture to facilitate development of the deposit was formed in mid-1979 between WMC (51 per cent) and the British Petroleum Group (BP, 49 per cent). Production commenced in 1988, and current annual output from the mining and treatment of 2.2 Mt of ore is approximately 65 000 t of refined copper and 1400 t of uranium oxide. Significant amounts of refined gold and silver are also produced.

Jan 1, 1993

By Walton S, Wheeler D. J, Sargent D. M, Ting L. Y

Goonyella-Riverside mine is an open cut coal mine in Central Queensland. One component of the mining operations at this site is an uncompacted spoil dump some 50 m above the natural ground surface and over 300 ha in extent formed as a result of bucket wheel excavator operations. Plateau area slopes are 0.5¦ to 1.5¦ with irregular outer dump slopes of 9.5¦ - 17¦Investigation was undertaken and a series of trials planned to assess the suitability of a variety of stabilisation proposals to meet the client's requirements and to conform with Department of Resource Industrystabilisation guidelines.

Jan 1, 1992

Against a background of deeper pits, the introduction of prestripping fleets and the need for closer control of operating costs (especially the waste removal component), Australian coal operations utilising draglines have in recent years become increasingly focused on:1. assessment of more efficient excavation methods; and2. application of explosive products and initiation systems which offer more flexibility than ever before.Additionally, developments in blast performance assessment techniques and equipment, and computer modelling and excavation monitoring systems have provided an improved opportunity to design a blast to achieve a desired profile suited to the excavation equipment and Sequence.

Jan 1, 1992

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