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By Gabriella Mendez

Worthy of note in Miss Bailey's paper are her comments on the attitudes of mining companies and their managers where women were employed, she says, "..another possible pitfall is reverse discrimination where in an effort to avoid being branded as having shown a person favouritism, supervisors end up treating the person in a manner much less than they deserve. This is manifested in denying an employee such things as challenging work, educational opportunities, promotions, or in the case of staff, fair merit increases." and further she says, "It has been observed that the treatment of women in non-traditional roles such as mining is different than for men in the same environment. There are people who treat women worse and some who treat them better simply because they are of the other sex." These statements may sound unjustified to today's audience, and whilst we need to credit pioneering women with having tolerated, understood and worked towards improving the mining culture, the move towards total inclusion of women in the workplace is still growing.

Jan 1, 1995

By Gardner CE

Uranium occurrences and the probable Australian reserves are discussed and the recovery and processing methods used in treatment plants at Radium Hill and Port Pirie, S.A., Rum Jungle and Moline, N.T., and Mary Kathleen, Qid. are reviewed. The broad aspects of the application of nuclear power in Australia are then considered, and those factors of greatest significance are highlighted. It is these factors that are most likely to dictate the future role of nuclear generation in Australia. In commenting on private industry applications, the paper emphasises that each case must be considered on its own merits, and a warning is given that general statements can be misleading. In the long-term situation nuclear power is considered to be capable of playing a leading role and the discussion covers desalination and high load industries although short term applications appear difficult to justify. In non-power applications for nuclear energy reference is made to isotopes and the uses of nuclear devices in mining and civil engineering with a pertinent comment on safety.

Jan 1, 1970

By David J. Dyet

Computer applications in the past five to seven years have become a typical and necessary practice in most modern geological offices. Manual calculations, interpretations and plotting of data can be, at times, quite tedious, inefficient and lacking in ac- curacy. The introduction of geostatistical and geological software can eliminate these problems. Computer applications in the uranium industry are not new; however, they are constantly being developed. A variety of soft- ware programs are available. Generally, these programs support most geological and geostatiscal applications in uranium mines. The Rabbit Lake Operation - Eagle Point mine in Northern Saskatchewan is a high grade mine, as one such case. Computer applications at the Eagle Point mine have been a mainstay in the geology department, since the mine's collaring in 1991. This paper presents a discussion on descriptions of programs, operations and applications of computers. It also explains and de- scribes the radiometric equipment used at Eagle Point. This pa- per will demonstrate how, by using computer systems, mine site information flows reliably with the involvement of computers.

Jan 1, 1996

Differentiation of a basaltic (?) magma occurred in an active volcanic area during the late Miocene and Pliocene, and a change in the general mode of extrusion from fissure flow for the basalt to explosion for the andesite reflects an accompanying increasing magmatic viscosity. A caldera formed after the flow phase was completed and was filled with coarse agglomerate, much of which has a fused appearance. After an erosion interval its shape was modified and it became gradually deeper as repeated explosions from growing andesitic volcanoes caused large quantities of pyroclastic material to be deposited. At the close of this phase the floor abruptly collapsed when a, large block of the underlying crust was engulfed. The incompetent pyroclastics filling the caldera steepened in dip and the ensuing fractures were filled by the rising magma as dykes and sills and a chonolith formed below the caldera at a shallow depth. The ensuing activity reveals a further stage in differentiation and biotite is an important new ferromagnesian to be observed in the new rocks.Fracturing of the surrounding basalts was most intense in the rocks forming the periphery of the caldera where steeply and flatly dipping faults resulted from increasing horizontal pressure directed towards the caldera.Further differentiation resulted in the increased crystallization of orthoclase felspar, as evidenced by the numerous intrusives of trachy andesitic composition. Magmatic freezing caused mineralizers to accumulate at the top of the chonolith. These eventually escaped and auriferous pyrites, tellurides, quartz, and calcite were deposited in the surrounding rocks.The flatly dipping fractures are the most important and can be expected at various depths in a zone about 4,000 ft wide surrounding the caldera. Latest movement along these was controlled by magmatic consolidation rather than the shape of the caldera. Some flat faults were able to remain open during mineralization and acted as a feeder for the shallower fractures, thus limiting the depths to which the steeper dipping fractures were mineralized with the possible exception of one particular Nw.-striking lode (the Crown-Crescent).INTRODUCTIONThe gold deposits of the Tavua district were discovered in 1932 and from 1935 to June, 1961, 1,985,041 fine ounces of gold were produced from 4,202,504 tons of ore. Of the original three producers, only the Emperor remains active in the...

Jan 1, 1962

By Claus Becker

The Mixshield is a tunnelling machine for water bearing soft soils. Developed on the basis of the Hydroshield, it extents the application of this machine to cohesive soils. The design of the drum-type machine allows three different applications 1. As shield with liquid supported face and hydraulical mucking 2. As Compressed-Air-Shield 3. As Earth pressure balanced shield. The Mixshield is employed on three big contracts 1. a 6.3 km ring tunnel in Hamburg, outer diameter 5.95 m, with a new developed segmented concrete lining 2. a 1.9 km pipe-jack job near Cologne, o.d. 3.6 m 3. Metro Lot 3 in Lille/France, o.d. 7.7 m, 3.2 km long with segmented concrete lining and a most sophisticated separation-plant The site experiences will be reported.

Jan 1, 1987

By T. P. Smirnoff, R. J. Redmond, K .. N. Murthy

To minimize disruption to the Hollywood District of Los Angeles, a mined station using the New Austrian Tunneling Method (NATM) was developed. This paper presents the key factors contributing to the settlements and dynamic behavior of the unique binocular station design.

Jan 1, 1993

By Ann G. Kim

Samples of gas were obtained directly from the coalbed during drilling of horizontal and vertical boreholes in six different formations. The samples were analyzed by gas chromatography for C1 to C5 hydrocarbons and for O2, N2, H2, He, and Co2. Methane in the gas varied from 63 to 99 percent; carbon dioxide from 0.1 to 15 percent. The CH4/CO2 ratio varied and showed no apparent correlation with age, rank, or bed. The majority of samples contained ethane, propane, and butane; hydrogen and helium were found in some samples. Oxygen and nitrogen were usually present, possibly as a result of air contamination. A more extensive sampling program would be necessary to establish relationship between the amount and composition of the gas in the coalbed and other factors.

Jan 1, 1973

By E. J. McKee

THE area discussed lies south of Canadian River in Hutchinson County, Texas, covering approximately 10 m. east and west and 4 m. north and south. Development is carried on in the manner usual in standard tool operations. No outstanding divergence from the usual methods is necessary as wells are completed in 35 to 55 days to approximately 3000 ft. Most of the time is lost in the upper part of the hole and is usually caused in driving pipe of larger sizes. After approximately 1500 ft., little trouble occurs. A comparison of 13 contractors drilling for Phillips Petroleum Co. gave the following averages: Drilling time from 32 to 63 days with a daily footage of from 49 to 87 ft. per day. The rigs furnished are National turnbuckle type with 6-in. irons and steel wheels.

Jan 11, 1926

By Kenneth N. Han, Xinghui Meng, A. J. Monhemius, G. W. Warren, E. Peters

The leaching of gold in ammoniacal solutions containing various oxidants in an autoclave has been investigated. Also studied are thermodynamic and kinetic aspects of the ammonia leaching of gold and silver. The variables studied included stirring speed, temperature, concentration of ammonia, ammonium, and various anions. Arrhenius activation energy values were found to be between 47.1 kJ/mol and 86.2 kJ/mol depending upon the kinds of oxidants used. An electrochemical reaction controlling mechanism has been proposed for the dissolution reaction. The leaching behavior of gold and silver from various ores in ammoniacal solutions containing various oxidants has also been investigated. The samples tested included sulfidic as well as carbonaceous refractory ores. The recoveries of gold and silver from these refractory ores were better than 96% within 2-3 hours of leaching time.

Jan 1, 1993

By Adele Garkida

Compacts of crushed waste window glass, fluorescent tubes, drinking glasses and laboratory glass wares were made at various proportions from 106 microns and minus 75 microns powders in combination with 5% bentonite as binder for each glass type, after several trials to determine compatibility of particle sizes. They were made using the uniaxial press at 10,000 psi and sintered at a temperature range of 700- 750oC. The results showed anisotropic shrinkage behavior for all the samples, exhibiting an axial shrinkage lower than the radial shrinkage. Sintered compact from waste drinking glass which comprised of 60% 106 microns and 40% minus 75 microns powders showed the least sintering shrinkage factor of 1.125, fused at 700oC and the highest shrinkage factor of 1.286 obtained at 750oC. This shrinkage behaviour connotes that sintering can be employed to utilize these waste glasses up to the maximum of 95% recycled glass content in ceramic tile production.

Jan 1, 2008

New technology is a significant factor in the present upsurge in world, and Australian, gold extraction and production. The main technologies in current use for gold production are described, referring to overseas developments. Areas where existing techniques have shortcomings or new methods are needed are pinpointed and discussed. Much research work on gold metallurgy is under way round the world, and many new developments have potential. Many of the current research activities round the world are covering unusual and striking areas, with surprising results starting to come through. Some of the "blue sky" techniques reportedly under investigation are identified, together with consideration of when changes in technology are of value. The consequences of new technology for personnel involved in gold plant operations will be raised, including the new education now required.

Jan 1, 1986

A new branch of the Institute-the Zululand Branch- was formed at the end of last year. After many months of preparation and perusal of address lists, it was realized that branch serving our members north of the Tugela was long overdue. A small steering committee consisting of Messrs John Selby, Dawid de Wet Smith, and Bill Kluckow got the branch of to a roaring start. They organized the inaugural meeting, which was held at the Richards Hotel in Richards Bay on 28th October,1993. Out of a possible 70 members residing in a 100 km radius, over half attended that first meeting!

Jan 1, 1994

By Gordon F. Revey

Hanging Lake Joint Venture recently excavated two conventional 42 foot diameter highway tunnels in the difficult ground conditions of Glenwood Canyon, Colorado. This paper outlines the type and success of the various Controlled Blasting Techniques that were used to minimize overbreak in the portal and tunnel excavations. The different Smoothwall and Cushion Charge loads used in the different ground types are described in detail. Delay Timing and Drilling Pattern variations are also discussed.

Jan 1, 1991

By J. Harrison Daniel

Increasing concerns of industrial hygiene and worker health issues and resulting regulatory actions, coupled with continuing advances in mining systems, are placing new burdens on the industry and Federal Government; particularly, mine ventilation departments. More encompassing worker health programs are required to respond to Federal promulgation of regulations and to keep abreast of techno- logical advances in the mining industry. The relationship between the mining industry and Federal agencies involved in rulemaking is presented, along with the rationale of an Industrial Hygiene Management Plan. This plan or strategy focuses on developing partnerships and collaborative research groups to address the controversial health issues facing not only the mining workforce, but our society.

Jan 1, 1993

By Freeman Bishop

The Nation's capital has one over- riding minerals-metals question: How long will prices and wages continue to move upward at the inexorable pace of the last year? Is the wage pattern to settle this year around 10%? The big industrial unions are coming into line, some of them later this year. Steel is standing in the wings for next year. Copper, steel, nickel and most other industrial metals have taken big hikes in their stride. Aluminum, which is making inroads into areas of industrial use formerly sacred to copper and some other metals, seems to be fighting to hold down its prices to attract customers from the higher-priced metals.

Jan 1, 1970

By Charles Willard Hayes

Shortly after the discovery of black phosphate on Swan creek, in Hickman county, Tennessee, prospectors familiar with the Florida phosphate came to the region and began the search for rock similar to that found in Florida. Among these was Mr. E. Slattery, who located at Linden, in Perry county. He gave a piece of the Florida rock to Mr. C. C. Sutton, and the latter discovered on Tom's creek a deposit which bore a strong

Jan 1, 1896

By Ritchie IC

Spiral separators have been used to treat heavy mineral sands in Australia for some thirty-five years. They were used as the primary treatment method until the advent of the Reichert cone, which largely replaced them, due to its compact design and relative ease of operation. Spirals continued-to be used as the final cleaning stage before dry separation of the heavy minerals as they remained the most efficient separator for this purpose.

Jan 1, 1986

By Eric Konigsmann

"The Pogo project is located on the Goodpaster River, 38 miles north of Delta Junction in east central Alaska. Sumitomo Metal Mining and Teck Corporation are planning to develop a 2,500 ton per day underground mine and mill at Pogo. A preliminary resource of 5.5 million ounces of gold has been identified in two flat lying lenses. An underground adit has been developed to facilitate underground drilling of the deposit and to provide samples for bench and pilot scale metallurgical testwork.Flowsheet development included the evaluation of several processing options. The final flowsheet selected includes SAGhall mill grinding, gravity concentration with intensive cyanidation and direct electrowinning, sulfide flotation with ultrafine regrinding, and cyanide leaching and CIP gold recovery from the flotation concentrates. Flotation tailings will be filtered for placement in a dry stack storage facility or disposed of as paste backfill underground. All of the CIP tailings will be disposed of underground as paste backfill. A pilot plant was carried out to evaluate the proposed flowsheet described above and to confirm the gravity recovery predictions.Great care was taken in the development of the flowsheet and site layout concepts to mitigate the environmental impact of the proposed operation. An overview of the site water management concepts is presented and the impact of water issues on the process flowsheet is discussed."

Jan 1, 2002

By Leon Lorenzen, Charlene Gokhale

"In excess of 24 x 106 tons (Eskom, 1997) of coal-derived fly ash is produced annually in South Africa for the production of electric power. A large quantity of this ash is disposed of as a solid waste in landfills, thus posing a serious environmental problem. Due to the shortage of landfill sites, new ways of utilising fly ash are needed. Recently several authors have shown that various combustion fly ashes can be converted into zeolites to obtain industrial products with applicability in environmental management. Geopolymerisation has emerged during the last few years as a possible solution to some waste stabilisation and solidification problems. henolic compounds have been shown to be toxic to soil microorganisms at the parts-per-million level. Indeed several of the organic compounds classified by the U.S. Environmental Protection Agency as priority pollutants, are phenols. Immobilisation of phenols by adsorption on zeolites and encapsulation in a geopolymer appears to be a promising solution to this problem.This paper reports a technique for the production of a low-silica sodium zeolitic material from fly ash (zeolite NaP1), and its application for the stabilisation of phenols by adsorption and subsequent encapsulation in a geopolymer matrix. A commercial zeolite, clinoptilolite was also utilised as an adsorbent. Due to their uniform pore sizes and large surface areas, zeolitic materials are suitable for ion exchange and adsorption of certain organic substances. Adsorption data show that the commercial zeolite, clinoptilolite was an effective adsorbent for organics. Adsorption data showed that between 51.2 ppm and 74.3 ppm of chlorophenol or between 15.4 ppm and 32.5 ppm of phenol could be adsorbed. Physical encapsulation of the coated zeolite loaded with organic within a geopolymeric matrix increased the compressive strength of the matrix from 28.80 kN to 40.79 kN. Leaching data for the various geopolymer matrices with encapsulated and loaded zeolites show no organics being leached from the system at a detection level of 2ppm. According to the SABS these would have been acceptable organic concentrations within a waste water stream."

Jan 1, 2003

As it is probable that a large proportion of the members of the Institute attending this meeting are connected with the metalliferous side of mining, the writer thought that, as coal and coke are required for various purposes in considerable quantities by their companies, some particulars of the coal industry might be of interest, especially when visiting such an important coal-mining centre as Newcastle. It is proposed to deal with the matter from the mining and economic point of view, as the geology has been so well and exhaustively dealt with in various publications referred to in the bibliography at the end of this paper. In the immediate vicinity of the city of Newcastle the collieries are gradually being abandoned, and during the past few years the Wickham and Bullock Island, Stockton, Hetton, Newcastle Coal Mining Company's "B," and the Australian Agricultural Co's Sea pit, have disappeared from the coal-producing list of collieries. AIl of these collieries worked the Borehole seam, from which, up to date, the largest quantity of coal has been produced in the northern district.It is the bottom seam of any present commercial value in the Upper or Newcastle coal-measures, and although the coal-in this seam has not been entirely 'exhausted in the collieries referred to, they have been abandoned for various reasons. For example, although about 60% of the seam (18 to 20 ft. thick) was left in the workings in the form of rectangular pillars under the city of Newcastle, this was not sufficient to 1?revent'the subsidence which took place about twelve years ago.Again, large quantities of coal in the Borehole seam have been left to protect the shipping arrangements at the Dyke, and other...

Jan 1, 1918