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Detailed mapping in the Permian-Triassic clastic sediments of the Southern Alps delineates a number of strike-slip faults, both dextral and sinistral, associated with the major Alpine Fault to the west and displacing a tight array of fault blocks. Concurrent steeply plunging folds are deforming early major folds of probable Cretaceous age, and generating schist locally. To the east a major collapse zone has developed along the crest of a Cretaceous anticline, located over an ancient Permian submarine scarp, with a number of small normal faults. Further east, extensive Carboniferous to Triassic rocks of much the same appearance are exposed as horsts and grabens in a large possible extension zone through central and east Canterbury. This may have crept incrementally from Cretaceous from the offshore Bounty Trough to reach the eastern margins of the Southern Alps in the Pleistocene.

Jan 1, 1990

By Rennie J. W

In the first five years of longwall mining at Pacific Colliery, special techniques of goaf sealing, gas drainage, goaf edge ventilation and goaf sampling were developed and used to o crcome the concurrent problems of spontaneous combustion and high methane emissions. The English-inspired back-return face ventilation system was modified to suit Australian mining methods and was first used as part of a 'Y' ventilation system and more recently was used with a 'U' system of ventilation. In conjunction with this ventilation system, the maintenance of a sealed goaf area was an essential element in the control of the spontaneous combustion in the goaf.

Jan 1, 1988

By Ash M

The world-class iron ore mines at Mt Whaleback, Torn Price and Paraburdoo located in the Hamersley Province of Western Australia must mine the Mt McRae Shale to obtain high grade ore from the Dales Gorge Member of the Brockman Iron Formation. The Mt McRae Shale contains a black pyritic shale lithology that reacts with ammonium nitrate-based explosives. This paper provides an overview of the problems associated with mining this reactive rock type as well as the development of a comprehensive procedure to safely and efficiently blast, excavate and dispose of this material. The strategy used to develop the procedure involved raising the awareness of relevant site personnel to the risks associated in mining the Black Pyritic Mt McRae Shale, obtaining the commitment of these personnel that a detailed procedure was required and that any procedure developed must be followed, otherwise the potential risks such as premature detonation were high. It was also necessary that an on-going training program be implemented so that all relevant new employees would be educated as to the reasons for adhering to the Black Pyritic Shale Procedure.

Jan 1, 1995

By Mazandarani M, Chabot L, Vichion K

Pitch-steering models have been developed for discretely advanced mining machines (such as heading machines and coal shearers) using small-angle geometry and there are illustrative examples of simulator predicted performance. Although simple linear models result from the analysis of open-based machines, sledge mounted machines require execution of a Linear Programming energy minimisation to determine the attitude of the machine base at each advance over the previously cut floor steps. An analytical approach is based on elastic beam concepts developed for such applications as longwall face conveyors, caterpillar tracked machines such as continuous miners and longhole drills. Simulation results for longhole drills show the expected performance of an automatic guidance system and the destabilizing effects of sensing deviation too far behind the drill bit. Certain drill bit boundary conditions are expected to assist TBM. steering studies in three dimensions.There is a real role in mining machine steering for the mathematical models used in flight simulators.

Jan 1, 1991

By Giedl JG

Technical applications of computers within the coal industry are expanding rapidly with an increase in the number of users and user locations. Collinsville Coal Company Pty Ltd is an example of a remote and growing user company which has a Telecom link to MIM's ICL mainframe computer in Brisbane. The Planning Department is one of the technical user departments at Collinsville, with a variety of VDU, plotting and screen graphics hardware supported by the MIM Computing network. Current applications involve the storage, retrieval and manipulation of borehole information, plan and map production, volume calculations from survey data and mine ventilation modelling for underground Operations.

Jan 1, 1983

By Evans A, Jones O

Surface subsidence resulting from "total extraction" of coal in the Collie Basin first occured in 1987 when Western Collieries Ltd trialled the Wongawilli mining method. Because very little quantitative subsidence data existed for the weak, Permian sediments, a research program was set up prior to the extraction of the first panel. The objective of the study was to be able to predict subsidence characteristics and effects prior to mining future total extraction panels. Attempts at predicting subsidence began using existing subsidence models from other coal mining regions, however, as more site information became available, it became clear that it was necessary to develop a separate, she specific predictive model for the Collie Coal Basin. Analysis of extensive field monitoring data for both surface and subsurface subsidence has produced a series of empirical models which can predict the shape of surface subsidence troughs and corresponding tilts, and strains for rectangular panels and describe the sequences of ground movement from the mine roof through to the ground surface.

Jan 1, 1992

The State of Western Australia has a land area of 2 525 000 km2, and is well endowed with minerals and petroleum products. In 1989 - 90 these products were valued at nearly A$10 500 million.

Jan 1, 1992

By Cunningham CG

Many epithermal gold-silver deposits areknown to occur in the Neogene-Quaternary volcanic complex of the central Andean region of southern Peru, northern Chile, western Bolivia, and north-western Argentina, an area of about 300,000 km2 where these volcanic rocks constitute the dominant cover. Some of the gold-silver deposits were mined during Spanish colonial times, as early as the 16th century,- whereas others were not discovered until the 19th and 20th centuries. The extraordinary gold-silver potential of this young volcanic complex, however, was not recognized until the 1970's when the phenomenal increase in gold and silver prices stimulated new exploration. New discoveries were made, chiefly in southern Peru and northern Chile, of high-grade ores in old mining districts and large low-grade ore bodies, both in old districts and in new areas having no history of mining activity. Many additional gold and silver deposits remain to be discovered within and beneath the young volcanic complex of this region.

Jan 1, 1990

By Browning E. J

The application of conventional dust control systems in British Coal mines has considerably reduced the incidence of pneumoconiosis. A number of new techniques have been developed involving extraction close to the cutting heads of mining machines which will be capable of controlling airborne dust with the greater intensity of production necessary in the present economic climate.

Jan 1, 1988

With the recent wider introduction of friction hoists of the Koepe type. for winding from depths of more than 3000 feet it has been found that failure by fatigue is the most common form of rope deterioration. Large numbers of wire breaks occur near the centre of the rope cross-section and it is difficult to detect these with certainty using the preferred d.c. magnetic test. For best results with conventional search coils their dimen- sions should be related to the typical wire break field pattern surrounding the longitudionally magnetised rope. The field of a broken wire was experimentally determined, using a Polish type MD6 Defectograph wire rope testing magnet and a short prepared length of rope with a movable simulated broken wire. The external field distortion perpendicular to the rope was measured by means of a gaussmeter and Hall probe. The advantages of this method are that terrestial magnetism and inherent rope "noise" have no effect on the results.

Jan 1, 1971

By Clark I, Stockton N, Warren L

Nickel flotation circuits currently experience difficulties in recovering fine particles of pentlandite less than ten microns. By agglomerating these particles using shear-flocculation it is hoped to improve the recovery of these fine particles. A sample of massive sulphide ore from the Kambalda region was separated using magnetic separation to obtain a high grade pentlandite concentrate (> 90 per cent). This was finely ground to produce a sample with particles of 50 per cent minus 10 um in size. This sample was then shear-flocculated using a variety of reagents, including xanthates, dithiophosphate and mercaptobenzothiazole (MBT). The effects of reagent type and concentration, conditioning time, impeller speed and type, and pulp density were studied. Froth flotation tests were also conducted on the shear flocculated pulps to compare the effects of xanthate and MBT on the recovery of pentlandite.

Jan 1, 1992

By Hikosaka A, Chiba A

In a fundamental study of the physical chemistry of steelmaking slag, equilibra bet- ween hydrogen-water vapour gas mixtures and liquid slags contained in solid iron crucibles have been measured for four binary slags, FetO-CaO, FetO-Si02, FetO-TiO2 and FetO-Al203 at 14000C. From the data, the activity of iron oxide and the ratio of ferrous and ferric ions (A = Fe3+/Fe2+) were calculated for the slag composition. The best ionic model is found to be that based on regular solution of cations. The oxygen distribution between slag and metal is quantitatively expressed by this model over a wide range of slag composition.

Jan 1, 1980

By Corbett GJ

Epithermal gold-silver deposits occur in young volcanic terrains where post-mineral cover commonly impedes the search for mineralisation. At the Togi Project in Honshu, Japan, a complex mineralised system is largely covered by post mineral volcaniclastics. A combination of high resolution electrical resistivity surveying and detailed airphoto interpretation has, with close geological control, enabled synthesis of structural and alteration characteristics of the Togi geothermal system, in turn permitting ranking of the prospects for drill testing.

Jan 1, 1990

It should be noted that with the passage of time all aspects of the mineral extraction process are becoming more sophisticated and complex. In order to deal with this, the education system should be geared to this continual technological advance.A new scheme is designed to attract high quality school leaven to take up courses serving the mineral industry. After graduation these students will play an important role in the areas of research and development which is essential for the growth of the Australian mining industry.

Jan 1, 1991

By Johns D. R

The producers of mineral sands on the East Coast of Australia might be regarded as having a simple task of selling Rutile and Zircon. Such is not the case. Differing quality and grain size requirements plus the dramatic increase in the percentage of mineral sold in a processed form have meant a large increase in the number of different end products handled. The resulting sales control problems are compounded by the need to be able to deliver against a large number of separate contracts which may relate to spot or long term sales in small quantities or in bulk shipments. Methods of helping management control this situation have been devised and incorporated into a suite of computer programs. Experience with the approach has been very satisfactory. The effect of changes to shipping schedules, commitment to new or changed orders, or proposed changes to production can be evaluated as and when necessary with little bother. Confidence in decisions taken is high since the process of data collection has been designed to involve

Jan 1, 1977

The known coal resources of South Australia are either of poor quality, or expensive to extract, or both. Export quality coal occurs only at great depth in the remote north of the State; the balance of the State's coal resources are suitable only for local electricity generation. Currently there is only one coal mine in the State, at Leigh Creek. This provides fuel for approximately 34% of the State's electricity generation, the balance being fuelled by natural gas. In the near future, new fuel sources must be developed to augment diminishing supplies of natural gas, and to cater for increasing demands for electricity. The South Australian Government has determined that future electricity generation will be based on the combustion of local coals. The geological and geographical environment of the known coal deposits and the quality of these coals are such that the most up to date and innovative technology must be applied to both extraction and combustion processes. The Government, the Electricity Trust of South Australia, and several Australian and overseas companies have embarked on an extensive research and development programme to ensure that these otherwise useless resources can be developed to the benefit of the State.

Jan 1, 1987

By Biao Q, Mizuta Y

Thermal constants such as thermal con- ductivity and thermal diffusivity of rock and coefficient of heat transfer of airway wall are the most important characteristic values which decide accuracy of prediction calcula- tion. However, quality of rock is not homoge- neous and water content in rock varies with location and so, a method for in-situ measure- ment of thermal constants must be taken in. The method developed by us is to measure in- situ rock temperatures at two different depths from airway wall. It is simple and we found its accuracy is good enough in the engineering Sense.

Jan 1, 1988

Geological modelling is a crucial preparatory stage to most facets of the mine planning of an orebody. The process of modelling involves skilled geological interpretation. Recent innovations in computer software and graphics hardware provide many tools which can be used to dramatically improve on manual methods of interpreting orebody data. Geological interpretation can be carried out quickly to produce accurate block models for many orebody attributes, such as grades, and these models can be easily updated locally as exploration and mine development data become available. The speed of the modelling process coupled with the mass storage capabilities of the computer now allows geologists to optimise the geological model or carry more than one model through to the mine planning phase.

Jan 1, 1987

By Harper B

The mining industry has developed a comprehensive view of the need to have production personnel well trained in the use and maintenance of mining equipment. A strong commitment from the industry to this view has been instrumental in creating an efficient, profitable and productive industry based on modem production processes, sophisticated equipment and a multi skilled workforce. As the industry continues to develop, and the skills and knowledge needed by productive workers continues to expand, the training processes adopted by the industry will need to develop in parallel, not only making use of the latest advances in learning theories, instructional design and technology, but also using these knew ideas in more efficient ways.

Jan 1, 1998

By Kruse JW, Kjar AR

Recently there has been increased recognition o'f the cost savings that can be achieved by the greater use of offsite preassembly for the construction of industrial plants. Preassembly is a method of construction which involves considerable offsite assembly of complete sections of an industrial plant in established fabrication shops. The preassemblies are transported to the plant site, often by large and oversize transport systems where they are set on prepared foundations, finished and interconnected to other sections of the plant as required. The concept of preassembly is not new, but widespread interest has been shown because site construction costs in all parts of the world have increased rapidly and often at a greater rate than in established fabrication areas. Particular interest has be focused on remote, isolated and inhospitable plant site locations. These areas require the import of skilled labour, the payment of high labour rate premiums and the development of infrastructure to support the workforce for the duration of the construction period.

Jan 1, 1983