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The discovery of copper and nickel sulphides in the Riwaka Complex in 1967 led to considerable exploration activity by a number of companies. Various exploration techniques used by these companies are summarised and discussed. Activity of these companies shows that mineralisation is mainly confined to the southern, ultramafic section of the Riwaka Complex where geological mapping recognised sixteen units within, or associated with the Riwaka Complex. Significant pyrrhotite, pentlandite chalcopyrite mineralisation is restricted to biotite feldspar pyroxenites and to clinopyroxenite units. Lesser and more erratically distributed pyrite chalcopyrite pyrrhotite mineralisation occurs in poikilitic pyroxene hornblendites, melanocratic gabbros, and in marginal diorite lenses. It is suggested that a linear belt of layered ultramafic and mafic rocks described in Fiordland by Williams (1974) may be a southern extension of the Riwaka Complex. The Riwaka Complex has been classified as belonging to the Picritic subtype, (Tholeiitic suite), of Naldrett and Cabri, (1976), and as such it is concluded that it exhibits substantial potential for the discovery of economic copper and nickel deposits. It is considered that the complex is a multiphase differentiated intrusion emplaced in a major tensional fracture zone that developed in a relatively stable tectonic environment, namely a succession of middle Paleozoic shallow water shelf sediments. Based on sparse available evidence it is suggested that the Riwaka Complex was intruded in the lower to middle Permian. It is further suggested that the tensional fracturing was initiated by the onset of subduction process which were responsible for the development of the Permian volcanic arcs and ophiolite belt in the north west Nelson area.

Jan 1, 1977

By M Robotham

In April 2013, Rio Tinto Kennecott Copper’s (RTKC) Bingham Canyon mine experienced what is arguably the world’s largest ever in-pit slope failure. The failure initiated along a major, continuous, low-strength bedding fault, named the Manefay bed, and comprised approximately 145Mtonnes of rock and waste dump material. Initial East wall slope deformations were detected some months prior to catastrophic slope collapse by RTKC’s slope monitoring systems. However, the failure mechanism was different to that which had historically been experienced in the prior more-than-100 years of open pit mining. Failure occurred as two separate events, the initial one likely consisting of a frictional failure of rock materials along the Manefay bed itself, before a second phase of failure occurred, which included a large mass of old rail dump material. The combination of these events led to a much larger failure run-out than had been anticipated by the RTKC team which led to loss of, and damage to, mining equipment and infrastructure as well as significant interruption to mining activities. Due to the diligent monitoring of the slopes no safety impacts were experienced at the mine, and as such the details and learnings from this failure can readily be shared with the broader mining and geotechnical industries to avoid similar recurrences elsewhere. This is an extended abstract only. CITATION:Robotham, M, 2018. Bingham Canyon Mine – from adversity to excellence, in Proceedings The Fourth Australasian Ground Control in Mining Conference (AusRock), pp 3–4 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 30, 2018

This paper describes the programing and specification requirements which affected the choice of excavation methods on the Melbourne Underground Rail Loop (M.U.R.L.). The various methods that were chosen are briefly described, and the three most used are compared in more detail. Excavation rates, cycle times and other statistics are compared for full face tunnel boring, full face drill and blast, and heading and bench using a road header excava- ting machine. The length of tunnel excavated is sufficient to enable meaningful statistics to be presented and the significant specifi- cation and geological factors are described to weight the statistics where necessary for purposes of comparison. Average tender prices are given for excavation and primary support to indicate the reimbursement sought by contractors to carry out this type of tunnelling.

Jan 1, 1981

By C Deacon

It is common practice to include microspheres or similar density reducing agents in inherently insensitive water-based commercial explosives to achieve detonative sensitivity in the absence of chemical sensitisation. It has recently become possible to similarly include microspheres in LDAN (low density ammonium nitrate). Further to previous studies and publications to determine the benefits resulting from the use of microsphere enhanced LDAN technology in blasting, additional advantages are described in this document. These include range tests at independent testing facilities (Universal Tech Corporation û USA) which reflect results observed in the field, and support theoretical assumptions made when the products were introduced. Additionally, on-site studies in opencast pits using Heavy-ANFO blends incorporating modified LDAN, show that monetary savings can be realised through significant advantages gained in plant throughput and explosives use.

Jan 1, 1999

The purposes of defining the mining environment for underground mass mining and the uses of characterisation data are outlined. The requirements for data in the areas of geology, surface and groundwater hydrology, topography and environmental constraints and geotechnical studies are identified. Emphasis is then placed on the collection and interpretation of geotechnical data for establishing the in situ stress regime and for rock mass characterisation. Methods used for diamond drilling, core logging, borehole logging, data analysis and presentation, rock mass modelling and rock mass classification are outlined. Finally, recent and potential advances in the state-of-the-art are identified in areas such as geophysical methods, measurement while drilling, computerised data collection and analysis, rock mass modelling, in situ stress measurement data presentation and interpretation, and some applications of rock mass characterisation data.

Jan 1, 2000

By Guo H

The importance of using disc cutters for rock excavation is reflected by their wide application in hard rock cutting machines such as tunnel boring machines and raise borers. The forces involved in the cutting process are those due mainly to thrust and rolling forces and are greater than that required by cutting picks. An interesting feature of cutting with discs is the formation of surface crushing, surface and sub-surface chipping and primary crack formation. Experimental, as well as analytical, work has been carried out to determine the optimum spacing between the disc cutters to control primary crack orientation. Wedge bit indenters were used to simulate disc cutters. The paper concludes by proposing a new approach to rock excavation by hybrid cutting based on controlling the primary crack Orientation.

Jan 1, 1992

By Summers DA

Faculty at the University of Missouri-Rolla have carried out research on the application of high pressure water jets as a means of excavat- ing coal for over 15 years. During the course of this time, a number of different concepts have been explored--the most recent of which has been to use high pressure water jets as a means of extinguishing an underground coal seam fire. This paper will examine the use of some of these technologies and will consider the results as a basis for discussion of further applications of water jets in the future. The structural pro- perties of coal which distinguish it from other adjacent geotechnical material and provide a considerable advantage to water jet cutting, will also be presented and the advantages of using this tool will be discussed.

Jan 1, 1986

By Urabe T

In June 1989 a diving cruise of the French submersible Nautile has been carried out on the North Fiji basin spreading ridge. The objective of the cruise was the geological and geochemical study of the active spreading axis and associated hydrothermalism processes. This operation was the third cruise of the French-Japanese STARMER project following two cruises of the R/V Kaiyo in 1987 and 1988.INTRODUCTIONAfter the Seapso III cruise (Auzende et al., 1986, 1988a and b) of the R/V Jean Charcot in 1985, the objective of the Kaiyo 87 and 88 cruises was the complementary Seabeam mapping of the North Fiji Basin spreading axis between WS and 22'S and a systematic sampling (water and rocks) and deep towing (TV and photos) at about every ten milles along the axis.

Jan 1, 1990

The treatment of beach sands in'' the Bunbury/Capel' area for the extraction of ilmenite is a very recent development in the mining industry in'J7estern Australia. Nevertheless since the commencement of production in 1956, ilmenite has become the sixth most important mineral produced. The increasing world recognition of W.A. as a major' Iiroducer of ilmenite is due primarily ' to its low chromic oxide. ; (Cr203 content,, 0,03% to 0.04%, combined with a medium to high grade TiO2 content, 54% - 6 , supported by large reserves, a'. stable government with close access to good shipping facilities.. Ilmenite is produced from-these deposits at low-costs, enabling the industry to compete on world markets despite high rates for sea freights because of the distance from.major markets.

Jan 1, 1964

The epizonal Ag-Pb-Zn vein deposit at San Bartolome is characterised by a base-metal sulphide assemblage containing the spectacular development of interpenetrating, bladed networks of pyrrhotite which have been replaced by marcasite and pyrite. A similar assemblage displaying the same crystal habits and textures are also a diagnostic feature of the Sn and Sn- Ag deposits of Bolivia. On this basis, it is reasonable to conclude that both deposits were formed from fluids of similar nature and origin. Although no economic accumulation of Sn is known in San Bartolomr, further comparison of the geologic setting, age, mineralogy, fluid inclusion data and magmatic association of this deposit with the Bolivian systems has highlighted additional similarities consistent with a hypothesis that more extensive Sn mineralisation might exist in the San Bartolomd area.

Jan 1, 1995

By Longworth C. R

This paper descrioes a case history of a coal mine which developed un'tahle roof conditions due to mass sliding of the overburden strata on a claystone band within the coal seam. The sliding is believed to have been initiated by stress relief associated with the removal of overburden alongside the entry portal of the underground workings. Once in motion, the roof block was kept moving by bulking due to roof collapse in the normal underground goafing operations. Control measures in the form of an earth and rockfill buttress against the entry portal and a sequential mining plan to create goaf areas alongside the entry portal have been initiated to attempt to limit movement. The operation has been continually monitored and a gradually decreasing pattern of movement is being re, orded.

Jan 1, 1981

During the last 20 years, manufacturers of Australian iron have given increasing attention to development of external markets for processed blast furnace slag. Slag has been in widespread use overseas and data on the performance of Australian slag in concrete lave shown it is suitable for that use. Chemical and physical properties of typical Australian slag products including air cooled, granulated and pelletised slag are discussed and compared with local natural aggregates. Special attention is given to pumping achieve- ments with slag concretes and the observed durability of concrete after many years service. More'recent applications for granulated slag as a sand replacement are discussed. It is concluded that'whilst more wide- spread use of slag is possible, the cost of marketing and transporting slag are likely to restrict opportunities unless for local usage.

Jan 1, 1979

THE Taranaki oil-field is situated on the western side of the North Island of New Zealand, at about its widest part, and may be said to be the most compact and fertile part of the Dominion, for, with the exception of the. upper half of Mount Egmont and of the ranges adjoining, which absorb 36,000 acres, the whole of the area, miuus what is taken up by the rivers land streams-is suitable for settlement, and certainly two-thirds is good land. The gross area oE the district is 2,417,299 acres.The principle rivers are the Wanganui, Mokau, Waitara, Patea, and Waiwakaiho. Mount Egmont, which is 8260 ft. high, used to be called Taranaki, and from it the district takes its name (the Maori meaning of which is "sloping peak ").

Jan 1, 1911

By Turco E, Pelizza S, Castellani F, Stanganelli V

Excavation are in progress for the building of tunnels of the waterworks in West Campania (Naples). The works afferent to part II envisage tunnelling through a miocenic clay formation over consolidated by two tunnels whose sections are respectively 50 and 10m2. Tunnel blasting is carried out by mechanical means. An excavator is used in the big tunnel, whereas in the small tunnel a roadheader machine is used for a short tract and a mechanized shield is used over a long stretch. The tunnel feature complex problems regarding stability. This is particularly so for the big tunnel whose face appears unstable. For this reason the clay on the face is sistematically bolted by means of 3-metre and 12-metre bolts. This prevent the use of a TBM for tunnel Excavation.

Jan 1, 1987

By Grieveson P, Rajakumar V

The reduction of an ilmenite concentrate with coal at 1000, 1050 and 1100¦C was investigated using thermogravimetry and X-ray diffraction, optical microscopy and electron probe microanalysis of the product. The effects of temperature, coal particle size, addition of ferric chloride and preheating of the concentrate in argon on the reduction kinetics and mechanism were determined. The rate of reduction increased significantly with temperature and was enhanced by the addition of the catalyst. The morphology of the iron was primarily determined by the degree of weathering of the particle. Significant coarsening of iron was obtained in the dense particles by the addition of ferric chloride. The sequence of reduction and the enhancement in the rate of reduction by preheating the concentrate in an inert atmosphere are discussed.

Jan 1, 1991

By Sheridan GD

Fifteen samples 'of clays and shales from the Adelaide area were selected from a total of 84 as representing material of possible value for the manufacture of light-weight aggregate. A detailed examination of the bloating. characteristics of these revealed four likely to be suitable. for expansion.' in a rotary kiln. One of these, a Tapley. Hill shale., was-fired in an 8 in. diameter rotary kiln, but con-tinuous bloating without ring formation in the kiln was not achieved. Steam,,-oxygen,, sulphur dioxide and carbon dioxide have been, suggested. as the agents of bloating. An examina-tion of .. the evidence : `leads to the conclusion that carbon dioxide derived from. carbonate minerals is likely to be the principal bloating agent. Attempts to bloat clays by the addition of mica were.not successful.

Jan 1, 1963

By Clark G

The latest addition to the grinding circuit at Bougainville Copper Limited is another 5.5m by 7.3m primary mill (No.13). The mill can operate in a primary or secondary mode. Its distinguishing feature is its capability for speed variation, by means of a cycloconverter-fed synchronous ring motor. The engineering and metallurgical reasons for selecting such a drive system are described together with aspects of the installation and commissioning. Results of investigations into the relationship between mill speed and grinding efficiency are presented. It is concluded that mill speed variation within the range 70 to 80% of critical speed has very little effect on grinding performance. Beyond this range, grinding performance deteriorates. The same conclusions were reached when mill speed was varied at reduced ball charge levels.

Jan 1, 1986

The original leases making up today's North Kalgurli Mines were developed by independent companies on an ad hoc basis. The major disadvantage which now arises is the varying levels of mining horizons. From Kalgurli Shaft in the south, through main Shaft and to Croesus Shaft in the north, there are three separate sets of levels. work has commenced to link the three areas with either common levels or new development which will facilitate common access and haulage via Main Shaft.Generally, the workings at North Kalgurli were established at the turn of the century. The introduction of techniques and equipment to bring the mine into the 20th Century has been difficult and slow. The general size of openings, a widespread workforce and complex ore distribution often make innovation and change more than a challenge.

Jan 1, 1985

By Nixon J

Open pit mining began in 1978 at the Woodlawn base metals deposit. For its ten years as an open pit the mine was financially unsuccessful as a combined result of difficult metallurgy and industrial unrest. In 1985 CRA bought out two American joint venturers with a view to going underground and a prerequisite to expending capital on developing an underground operation was to improve the industrial climate, work practices and mining methods.Following feasibility work, continuous production from the underground mine began in 1986 using mechanised cut and fill methods and a workforce trained under a multiskilling program. Men with no previous underground experience were trained by supervisors with backgrounds as miners to undertake all the work that is required with increases in skill levels being rewarded with increases in pay.

Jan 1, 1992

In the geologically prospective nations which rim the Pacific Ocean, mineral deposits offer great potential to create wealth for social and economic development. The paper first examines the geological and economic attributes of potential mineral wealth based on current outlook assessment of all significant base metal deposits discovered to 1988 in two Pacific Rim nations - Australia and Canada. The variability of mineral wealth among the economic deposits evaluated and the major contribution of the few world-class discoveries to total mineral wealth are highlighted. Then, the essential but too often neglected linkage between the makeup of potential wealth and its actual realization is analyzed. The impact of taxation and the role of exploration are crucial in this regard. Finally, the ingredients of exploration success, prerequisites for realizing the mineral wealth of nations, are examined.

Jan 1, 1995