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During late 1953 and early 1954, tests were carried out in Sydney metropolitan brickpits in order to determine if some improvement might not be effected in the personal shock, fly rock and possible ground displacement accompanying daily blasting occurrences in the numerous quarrying activities of the metropolitan area. As a result of this preliminary work (Reid, 1954), the Department of Mines decided to further investigate the problem with a view to placing this type of blasting on a sound economical and safe basis for both operator and nearby residents alike. To assist in the work, a Cambridge Universal vibrograph was acquired.Human safety was the first consideration followed by property damage to homes and factories in the extractive areas. Although most of the actual field work has been confined to the Sydney metropolitan area and in particular to the large clay-shale quarries, many cities and country towns have blasting problems associated with the extractive industries, engineering projects both above and below ground level, and in building excavations to which the results may apply.The following figures illustrate how much activity of this type is located around cities and towns:Sydney Metropolitan Area:

Jan 1, 1958

The large rotary blast hole drills for hole sizes of 250 to 375 mm in diameter have been utilized by large open pit metal and coal mines for production drilling all over the world. The design of such rotary drills is in most cases about two decades old and it has not been done much in order to apply a modern technology on rotary drilling. The most modern large rotary drill, Tamrock RI 10, consists of an advantageous rotary head with a squirrel cage AC motor controlled by a frequency converter, a beneficial mast structure with a possibility for inclined drilling, hydraulic driven, independent crawlers, and a modern ergonomic cabin to provide a comfortable working condition for the oper- ator. Several automatic features are available as options. The rig has been designed to be operated by one man only. With this modern rig the produc- tion rate can be increased and production cost kept on a low level.

Jan 1, 1989

And it takes more than good organisation. You may read or heard this poignant reflection: We tried hard, but it seemed that every time we were beginning to form up in teams we would be reorganised. I was to learn later in life that we tend to meet any new situation by re-organising, and a wonderful method this is for creating the illusion of progress while producing confusion, inefficiency, and demoralisation This was written by the Roman Gaius Petronius in AD65. How much have things changed in nearly 2,000 years? What then does it take besides the fundamentals and good organisation to build a successful career in a successful organisation? I'm prepared to venture a list of what I'll'call Tips for Young Professionals. If you've got what it takes, and apply these, I think that you'll gain a great deal of satisfaction from your career, even if you don't reach the distant target each of you should have in mind now. So settle back in an advice-receiving mode, and please forgive me if I come across as a master of the bleedin' obvious, as Basil once accused his wife Sybil of being in the unforgettable Fawlty Towers.

Jan 1, 1990

A novel fracture-plane control blasting technique with particular application in wall-control blasts in mines employing medium to large diameter boreholes is described. It consists of a string of nested holes, each nest consisting of a large diameter charge-hole flanked on either side by a small diameter satellite hole. Each nest is shown to be an analog of a pressurized hole with diametral notches along its length. This 'equivalent-notched' hole concept for generating controlled fractures along preferred directions has been successfully investigated in the laboratory and in the field. The technique has been used to generate controlled fractures on a quarry bench in highly jointed limestone. The resulting blasts with a 250 mm diameter central charge-hole and 50-75 mm satellite holes show that two nests of such holes almost 5 m apart could be joined by a single co-linear fracture. The design range of diameter ratio between charge-hole and satellite hole is 3 to 6 and spacing is 3 to 5 charge-hole radii. With careful matching of explosives and decoupling, and combination of diameter ratio and spacing, it would be possible to connect two nests of such holes more than 20 charge diameters apart by a single controlled fracture plane. The relative merits of the technique against existing wall-control blasts are discussed, and guidelines for practical fracture-plane control blast designs are discussed.

Jan 1, 1990

An exploration and preliminary mine design contract was undertaken in Thailand to establish whether adequate lignite resources existed for the addition of future power generation plant through to the year 2000. The lignite ranges in heat value from 14 to 24 MJ/Kg (air dry basis) and occurs in 2 major seams consistituting measured reserves of 536 Mt (with an ash cut-off level of 45 % on an air dry basis) and a strip ratio of 4.1 bank cm/t. The paper describes the pre-planning, programming, equipment used, project management, logistics and exploration methods adopted to undertake the contract in a monsoonal area using Australian drilling and geophysical contractors.

Jan 1, 1983

By Johnson N. W, Munro P. D, Pease J. D

The Lead/Zinc Concentrator of Mount Isa Mines Limited processes complex fine grained ore from the Isa and Hilton silver-lead-zinc orebodies, producing lead concentrate, zinc concentrate and (until 1996) a low-grade middlings (LGM or bulk) conc

Jan 1, 1997

Computers represent substantial capital investment. A better return on that invest- ment comes from more effective use of the computer's facilities. By using Telecom's data communications facilities, more people in more locations can have ready access to those facilities.

Jan 1, 1983

By Thomas CG, Armstrong GJ, Lynch KS

A small glass walled pot grate has been used to simulate drying of iron ore pellets in a travelling grate plant. This equipment has enabled the effect of decreasing grind and de- creasing pellet bulk density on plant production to be quantitatively predicted. These predic- tions are compared with plant experience. The use of the laboratory simulator in comparing the effect of various additives on plant production is also described and substantial improvements in both the goethite and free-water drying periods are predicted.

Jan 1, 1972

This paper examines the impact of the time value of money on the location of mining facilities, as examplified by a central processing plant serving several mines. Three approaches, the Euclidean-Distance Approach, the Gravity Centre Approach, and the Rectilinear-Distance Approach, commonly applied to a single facility location problem were employed in the study. The objective function in all three models was the updated value of the following three costs influenced by the processing plant location and defined within the framework of the continuous model of value representation and the continuous interest rate convention: I. the costs of transporting the useful mineral from the mines to the plant, 2. the costs of constructing the transportation links between the mines and the plant, and 3. the costs of maintaining these links over time. Results of the study show a substantial impact of the time value of money on both the processing plant optimal location and the opportunity cost of neglecting the time value of money in the locational considerations.

Jan 1, 1995

By Dunbavan M, Mallett C. W

The sequence of development and back analysis of the failure of a spoil pile in the 1B pit of the Moura Mine are given. The mode of failure was a two-wedge mechanism with a basal slip plane passing through a clay band about 2 m below the pit floor. Remedial actions for improving spoil pile stability are discussed.

Jan 1, 1981

By G D. Richmond, J C. Chomley

Copper has been mined intermittently at Gunpowder, north of Mount Isa, since 1927. Most ventures have had some initial success but fluctuating copper prices, the small-scale of the operations and the remoteness of the site led to closures or sale. Processing routes have included direct sale of high grade ore, flotation of oxide and sulphide concentrate, and copper cement production from mine solutions. Copper cathode has been produced by heap and in-place leaching coupled with solvent extraction and electrowinning (SX/EW). Aberfoyle Limited recently purchased the Gunpowder operation and is expanding operations. An innovative high recovery tank leaching process, including a low temperature, low pressure autoclave, has been adopted. Copper cathode will be produced from an expanded solvent extraction/electrowinning plant at approximately 45 000 tonnes per year. The combination of expanded throughput and high metal recoveries will make Gunpowder a cost competitive producer.

Jan 1, 1998

A survey of leaching systems for the dissolution of gold has been undertaken and their advantages and disadvantages evaluated both from their effectiveness at leaching and their compatibility with carbon- in-pulp (CIP) and resin-in-pulp recovery. In the near future it is almost certain that cyanidation in some form will remain the leaching system of.choice although economic and environmental pressures could see the introduction of other leaching systems particularly for treating refractory gold ores. The most likely alternative leaching systems appear to be acid chlorine, acid thiourea and ammoniacal thiosulphate. INTRODUCTION High grade reserves of readily recoverable gold ores are gradually being depleted which, inevitably, must create a greater awareness amongst gold producers, of the efficiency and, in some cases, the suitability of present day metallurgical processes for treating low grade, complex and refractory deposits. One of the key steps in the extraction of gold is the dissolution of the metal using chemical reagents which, ideally, should be cheap or recyclable, selective, non-toxic and compatible with down-stream recovery processes. In practice, meeting all these critera is difficult - if not impossible - particularly in view of the stringent environmental impact requirements which must be met Nowadays.

Jan 1, 1982

Mineral sands are different to almost any other commodity; however, it shares similarities with other commodity types, such as the importance of quality constraints of iron ore and coal or the importance of physical properties of diamonds. The mineral sands industry consists of two principal product streams; titanium dioxide minerals û in the form of rutile, ilmenite and leucoxene, and zircon. The principal valuable heavy minerals (VHM) include ilmenite, leucoxene, rutile and zircon. Variations of other titanium minerals occur between the end members of ilmenite and rutile, including pseudo rutile and anatase. Most mineral sands deposits are found in unconsolidated fossil shorelines several hundreds of metres to tens of kilometres and occasionally hundreds of kilometres inland from the present coastline. Mineral sands orebodies essentially fall into two categories based on the mode of deposition: alluvial or aeolian. Alluvial deposits are further split into marine beach placers (or strandlines) and lacustrine heavy mineral (HM) accumulations. Exploration for mineral sands involves the positive identification of key criteria leading to the focus of exploratory surface sampling, augering and drilling. Assaying is primarily focused around determining the percentage of HM contained within a given sample. Other results of interest include clay fines, sand and oversize. Metallurgical/mineralogical assessment is often undertaken via laboratory scale bench tests that replicate the wet concentration and dry mill processing routes. The most critical component in resource assessment for mineral sands is about quantifying HM grade, then mineralogical assemblage and then quality of those mineral species. This will determine whether a mineral sand final product is marketable or not. Mining of mineral sands is conducted either wet or dry. Wet methods are generally preferred for large tonnage, unconsolidated and low clay orebodies. Where ground conditions are hard and orebodies are small, high grade and discontinuous, dry mining techniques are generally employed. Concentration of mineral sands from the primary ore is carried out in two sections; wet, utilising sizing and gravity differentiation between HM, VHM, clay and quartz, and dry, exploiting the magnetic, electrostatic and to a lesser extent specific gravity (SG) properties of the minerals of interest. Mineral sands exploration, mining and processing faces the same operating challenges as the rest of the resource sector. Added to this are the issues that are unique to mineral sands and to which the industry devotes considerable resources to developing solutions.

Jan 1, 2009

By Isaac AK

The combination of shot-firing and stage loader, and a prop and bar support system is an accepted drivage method. The support configuration is based on the final prop density, and assumes relitively uniform load sharing between the props. During the development of a longwall faceline at a medium depth (approximately 600m) British coal mine using such a drivage method, a fall occured overnight, effectively closing approximately 40m of the drivage. The severity and speed of the fall prompted an investigation into the performance of the temporary support system installed prior to chock installation. This paper deals with the investigation which disclosed some major contributory factors towards loss of strata control.

Jan 1, 1986

By Hughson B

At present sane man-made Improvements and natural features are constraints on unlimited underground mining. 7 hey will continue to remain, as constraints on the future high production mining systems as wall. Unless these constraints are overacTe by research, where possible, future high production systems may became unacceptable. 7 he areas of future research include improved subsidence prediction techniques applicable to future mining systems, subsurface subsidence behaviour, mining systems capable of producing no surface subsidence and subsidence damage assessment.

Jan 1, 1988

By M Fylak, R Wenda

Advanced preparation techniques open new ways for SEM and X-ray diffraction (XRD) investigations on hydrating cementitious systems. In this paper the early time hydration of Portland cement is studied with advanced cryo scanning electron microscopy techniques in combination with in situ X-ray diffraction and heat-flow calorimetry. The application of preparation techniques and analytical methods to Portland cement hydration are presented and discussed. Some aspects of hydration reactions are focused. The reaction products of the first minutes, changes in ettringite morphology, AFm formation during the deceleration period and the visualisation of C-S-H microstructures were special points of interest. X-ray diffraction analyses and Cryo-SEM images gave essential information about phase development, reaction kinetics, microstructure and morphology of hydration products. Portlandite, AFt and AFm phases were detected by in situ XRD. Cryo-SEM analyses enabled high resolution imaging and EDX-analyses of cement particles and reaction products. The results of the different analytical methods were compared to obtain detailed information about crystallisation processes and microstructural development during the first three days of Portland cement hydration.

Jan 1, 2008

By Eupene GS

The Early Proterozioc Pine Creek Geosyncline hosts a large number of gold showings. Mineralisation types include stratiform, synsedimentary deposits within iron formation and carbonaceous mudstone; disseminations in granophyric intrusives; and quartz vein related concentrations in the form of shear fillings, saddle reefs and stockworks. Stratiform gold deposits preferentially formed near penecontemporareous faults during periods of basin instability. Intrusive basic magmas later assimilated some stratiform mineralisation and subsequently redeposited it within differentiated phases. Gold was again remobilized during regional deformation and metamorphism. Stratiform mineralisation was upgraded insitu in high strain zones and gold was mobilized into metamorphic fluids. Fluid induced fracturing during prograde metamorphism and later uplift caused the deposition of extensive gold rich vein systems. The genetic relationship between gold deposit types is reflected in the clustering of showings along regional anticlines, and provides a powerful exploration tool. The large volume of 'exhalative'òmaterial in the Geosyncline with elevated gold content suggests significant economic stratiform mineralisation may be present, and probably provides a source for later disseminated and vein deposits.

Jan 1, 1984

By Boyd G

This paper describes the planning, analysis, design and operational experience of highwall mining based on auger drilling techniques applied to thick coal seams exposed in an opencut highwall. Being the first time such technology has been used in Australia, a large commitment to technical design and logistics planning was given by Callide Coalfields Pty Ltd. This commitment included technical and operations management and supervision, mine services, and the retention of consultants to undertake geotechnical analysis, instrument preparation and instrument installation.

Jan 1, 1991

By Greenwood AG

Research into cemented rock fill at Mount Isa Mines Limited since 1992 is described. The key mechanisms controlling segregation during stope filling with cemented rock fill are described and include the gravity flow mechanism which is described in detail. Examples are provided to demonstrate these mechanisms. Comparisons are made between Mount Isa Mines' cemented rock fill and slurry-based cemented rock fills. Recent backfill stability modelling using a three-dimensional finite clement program is described.

Jan 1, 1998

The most frequent initiation of coal dust explosion results from the ig- nition of high methane volumes, often at low concentration close to the minimum flammability limit, by a weak ignition source, e.g. frictional sparks. Tests performed in the 400 m underground test gallery of 7.5 m2 cross section indica- ted the following: 1. Methane at 200 m3 volume and con- centration 4.0 - 5.0 % CH4 may initiate the coal dust explosion. 2. Suppression of explosions result- ing from such initiation is very difficult, even when employing triggered, barriers.

Jan 1, 1988