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Alternatively are they a necessary evil'? Exploration geologists are a much higher profile group but then again the higher they are the bigger they Bill. At a mine site they are reluctantly being accepted as equals by mining engineers given the requirements of the `Code' in the reporting of Ore Reserves. How best can mining geologists service their customers? Are more revealing questions to be answered in who are their customers? In the past mining geologists lived isolated existences pouring over plans and sections, now with user-friendly software packages available and the use of LAN, mining geologists and mining engineers talk electronically - God forhid what the future might hying - they might even talk to accountants and metallurgists!

Jan 1, 1997

By McAuley T. J

Computer software is an integral part of mining operations today with many sites using six or more software packages on a daily basis. However, the use of these different programs generates the need for substantial staff training. The current trend toward large integrated packages to solve this problem is counter-productive because the relatively small companies producing specialised mining software do not have the resources to develop quality software with all the required features. Software standards are being proposed by various parties but recent history indicates these will be unsuccessful. An alternative approach is suggested using the various standards which have been developed for the Windows operating system.

Jan 1, 1995

Environmental management of minesites in general, and management of water discharges in particular, is receiving ever-increasing attention. One key component in the successful design and operation of water management systems is to address the presence of sediment in the water being conveyed. Sediment erosion in the mining environment is often greatly exacerbated by disturbing the ground surface of vast areas of catchment. If sediment avoidance, transport, deposition or release are not adequately addressed, the impact on water management facilities can include loss of storage and hydraulic capacity, more frequent equipment replacement, increased operational costs and potentially environmentally unacceptable sediment discharges to receiving waters. An overview of sediment management within water facilities is presented here, and design of one particular approach, the use of settling basins for sediment removal, is discussed in detail. Examples are used to illustrate lessons learnt where particular approaches to sediment management have been found to be lacking. The common themes in the lessons learnt include the need to characterise hydrodynamic conditions and sediment properties in the water source, to set performance targets for sediment management, and to develop operating procedures to meet these targets under a realistic range of scenarios. The examples show how analysis of expected performance of sediment management can help with planning of operation and maintenance strategies. For settling basins, use of a simulation model that includes the effects of turbulence on settling can provide considerable benefits in optimising basin design and evaluating performance. Even in the most basic approach to sediment settling, establishing performance targets based on design flow and sediment characteristics is critical.

Jan 1, 2003

By J Nemcik, E Baafi, I Porter, G Spinks

Spray-on liners used in the mining industry for ground support and stabilisation applications are either cement based (æshotcreteÆ) or polymer based (æthin spray-on linersÆ). Some thin spray-on liners are a blend of both polymer and cement (eg Tekflex). A small number of thin spray-on liners (TSLs) have been trialled in Australia as potential replacements for steel mesh in roadways and other underground mining applications; however, they were found to cure slowly and the cured coatings became brittle after an extended time in place. The University of Wollongong in collaboration with the Australian coal mining industry has shown that a viable polymer-based alternative to steel mesh in underground roadway support applications can be developed to eliminate the use and handling of steel mesh. The work to date has: established the feasibility of developing polymeric alternatives to steel mesh in underground roadway support applications; identified the physical and material constraints to be endured by any new polymeric skin reinforcement system by measuring the mechanical properties of steel mesh; identified materials that can be spray applied; and demonstrated that polymer mechanical properties can be optimised to produce similar mechanical properties (elastic modulus, yield stress, elongation-at-break, etc) to steel mesh. The identified materials will: allow the face support cycle to be fully automated, or at least remotely operated and installed; remove personnel from the immediate face area; and substantially improve underground roadway development rates.

Jan 1, 2008

By Bourke J. H, Ashcroft T. B

Many changes have occurred in the world market for manganese over the last five years. Among these, the emergence of divided steel processes for the hot metal refining of pig iron is affecting the use of both ferruginous manganese ore and ferro manganese, at this stage particularly in the Japanese steel industry. Subsequent demand for higher quality manganese materials is promoting the use of thermally beneficiated products such as sinter. In addition, many processes are being developed for the direct smelting of fine manganese ores, of which plasma technology is the most advanced. Cost pressures and product quality requirements are encouraging pre- viously self sufficient countries such as The People's Republic of China and the USSR to import high grade manganese ores to supplement indigenous lower quality supplies. At the same time, Brazil has been provided with the impetus to convert its substantial reserves of ore to value added products.

Jan 1, 1988

By T E. Norgate

Salinity in Australia is caused by over irrigation and land clearing for agricultural use over the last 100 years. It is now the biggest threat to the quality of land and water in the Murray Darling Basin and Western Australia. Pumping the saline waters straight into the ocean or transporting the solid residue (mainly sodium chloride) to the ocean after evaporation of the water is expected to cost the taxpayer millions of dollars every year. This paper proposes that the salinity problem of Australia, at least in part, can be converted to an asset rather than a liability if it is exploited and used to make value-added products. The more value made out of saline waters, the more saline water is processed and therefore the more salt is extracted from the land. The value-added products that can be made out of saline waters are numerous and diverse. Rough calculations show that value addition to the saline waters could potentially generate up to $A 200 million per annum business in the Murray-Darling Basin. Although it is a challenge to make cost competitive products and find markets for these products it is possible that up to $A 100 million per year may be gained from import substitution. Value addition to salinity would also reduce the threat on the environment and existing agricultural industry. Investment to add value to salinity will create business in the region, nurture the local small population communities, and increase services and long-term employment.

Jan 1, 2002

There are a number of factors affecting the discovery and develop- ment of uranium in Australia which makes this mineral almost unique and quite different from other minerals. I. The role of the Australian Government, which initially encouraged the discovery by offering rewards to prospectors who discovered deposits that could become economic. 2. At a later stage, the Commonwealth and South Australian Govern- ments prevented the development and production of "new mines" by refusing to grant mining title and refusing to allow sales of uranium by not issuing export permits. 3. The unique property that uranium and its daughter products possessed, i.e. radioactivity, meant that any person who purchased a geiger coun- ter could go prospecting, even though they had no previous experience in prospecting and they had an equal opportunity of discovering a new deposit as a company or independent geologist. 4. Because the exploration/demand for uranium didn't occur until the 1940s very little background geological information or models were available and so the early discoveries tended to become the locus for exploration rather than moving into areas which might on geological concepts lead to exploration programmes based on geological models. Because of the lack of knowledge there was the exchange of geologists from the U.S. Geological Survey and the South Australia Geologist Survey.

Jan 1, 1988

Types of structure found in 'Jest Australian beach sands are described. Their recognition by geostatistical methods follows nth a discussion of the effectiveness of sampling patterns. Examples of structures are given, and an account of their effect on valuation procedures.

Jan 1, 1977

The capacity of chlorine based solutions to rapidly and effectively dissolve coarse gold in oxide ores is well established. The inherent advantages of chlorine are high dissolution rates (10 - 100 times those of cyanide), and low cost. The high dissolution rates mean that coarse or poorly liberated gold may be dissolved over relatively short periods and hence ore particle size may cease to be such a critical factor. The cost of size reduction to allow adequate gold liberation in order to achieve an adequate gold recovery is less of a consideration when using chlorine than in traditional plant or heap leaching cyanide-based treatment systems.Because chlorine based solutions capable of dissolving gold evolve an unpleasant vapour phase with the potential for significant chlorine losses into the atmosphere, traditional heap leaching with active solutions being sprayed onto prepared heaps is not possible. The ore must be covered and the solution may be introduced beneath that cover through prepared injection `wells' and recovered through production 'wells'. The pit is flooded with active solution beneath an overburden or cover with the solution migrating from the injection 'wells' to the production 'wells' over a period of around five - ten days.

Jan 1, 1992

By Paine GG

The in-situ retorting of shallow oil shale deposits is an attractive alternative to the material handling problems of conventional open pit mining techniques, which involve removing overburden, fragmenting and transporting the shale to a fixed retort, and finally disposing of the hot spent shale.For in-situ retorting to be successful, the oil shale has to be fractured and the fragmented rock expanded into a void, to allow controlled propagation of a flame front through the in-situ retort. The principles of cratering with explosives have been used to develop a process for the in-situ fracturing of a thin oil shale deposit overlain by a formation of porous rock. The overlying porous rock formation is first compressed by explosive charges to create voids in the porous rock. The oil shale is then fragmented and pushed in to the voids with separate explosive charges. This paper discusses methods of creating voids in porous rocks with minimal surface disturbance, and then methods of obtaining the most uniform fragmentation of the shale. The whole process can be completed, in practice, in one blast. The results of an experimental blast are presented, and possible modifications are then discussed.

Jan 1, 1985

By V Rajakumar, S Trang

Titanium has the potential to become the third wave of light metals used in high volume applications, following on from aluminium and magnesium. These light metals have functional attributes that can meet many of the goals needed for societyÆs transition to sustainable development. CSIRO has initiated a Light Metals Flagship to focus additional R&D efforts in support of the light metals industry. The vision of the Light Metal Flagship is for Australia to lead the Light Metals Age by reducing the costs and environmental impacts through innovative technologies for these metals. Life cycle principles will be used to identify novel technology pathways for metal production and product manufacture that are more energy efficient, less capital intensive and incorporating eco-efficient material flow chains.Under the auspices of the Light Metal Flagship, a Life Cycle Assessment (LCA) of titanium metal production was carried out with mineral sands mining of ilmenite as the starting point. Upgrading of the ilmenite to synthetic rutile by the Becher process and titanium metal production by the conventional Kroll process were the processing routes considered. Two alternative processes for titanium metal production, the FFC Cambridge process involving direct electrochemical deoxygenation of titanium dioxide, and a plasma process for producing titanium powder from titanium tetrachloride were also examined using LCA methodology and compared to the Kroll process. The environmental impacts included in the LCA were greenhouse gas emissions (Global Warming Potential, GWP) and acid rain gas emissions (Acidification Potential, AP). The Gross Energy Requirement (GER) of each process was also determined.These results for titanium, along with those from previous LCA studies by CSIRO on aluminium, magnesium, steel and stainless steel production, were used to show that despite the relatively large amounts of primary energy required for the production of these light metals, their special properties (eg corrosion resistance, strength and light weight) mean that these metals offer potential GER and GWP reductions compared to other competing materials in a number of applications, when viewed on a life cycle basis. Two applications considered in the paper are the lightweighting of motor vehicles and chemical plant equipment manufacture.

Jan 1, 2004

By Collings P. S, Adair D. L

The Upper Robe (Robe Gorge) deposits occur in Kumina Creek and the Robe River, some 20-40 km upstream from mining operations at Pannawonica. The Gorge Deposits were rec- ognised, mapped and sampled in 1962-3 and re- examined in detail in 1971. Approximately 180 mineralized occurrences were mapped in 1971 on 1:4800 scale and 50 of these were remapped in detail at 1:1200 scale. Eighty cross sections were measured and sampled and 300 geological maps prepared. In addition 88 holes totalling 7388 feet were drilled in three occurrences considered to have the greatest potential. The Gorge Deposits occur in the Robe Pisolite unit which forms thin remnant crusts, bay fillings and occasional cut-off meanders along the edge of the present streams. Less than 50 of the deposits have tonnage potential of one million or more. Consequently exploit- ation of the Gorge reserves must be considered as a very uncertain, long range possibility because the deposits are small and scattered throughout the gorges in the area, thereby necessitating costly railroad spur lines to gain mining access. Grade of the occurrences is extremely variable over short distances both vertically

Jan 1, 1973

By Dhawan AK

On 8 July 1993, a landslide of about one million cubic metres of rock blocked the river Satluj near Sanjay Vidyut Pariyojana - Bhaba project and caused flooding into the Bhaba Power House (120 MW) resulting in suspension of power generation. The concerned authorities desired an early removal of the blockade by an underwater blasting operation into the over topping water to reduce the water level at the blockade and resume power generation in the power house. In the absence of underwater drilling, it was essential for the blasting technique to be used where no cavity to confine the explosive was required. For this reason mud capping and plaster shooting with directional throw were used and additional specially fabricated mild steel pipe charges were used under high current for an underwater trenching operation. By employing these techniques the river blockade was removed up to the required depth and on 8 September 1993 the Power House resumed the power generation.

Jan 1, 1995

The Matakan Unit of New Ireland, Papua New Guinea is a highly fossiliferous lagoonal deposit containing numerous coal pods and lenses. The unit is strati graphically part of the massive reefal Lelet Limestone of Miocence age. These organic-rich sediments have a high hydrocarbon potential as evident from microscopical observations as well as Rock- Eval pyrolysis data. The coal is varied in regard to dominant macerals, vitrinite being predominant in some parts and pollen and spores present in sufficient proportions to constitute a cannel coal elsewhere. The highly fossiliferous carbo as Rock-Eval pyrolysis data. The coal is varied in regard to dominant macerals, vitrinite being predominant in some parts and pollen and spores present in sufficient proportions to constitute a cannel coal elsewhere. The highly fossiliferous carbonaceous sedimentary rocks associated with the coal are rich in pyrite expressed in the sulphur content (19.7 - 22.8%). A high primary productivity and anoxic sediment pore waters or just above sediment - water interface have given rise to sufficient organic matter accumulations to yield a potential hydrocarbon source rock. Atomic H/C ratios of the coals are between kerogen type III and type II mainly, expressing the mixed nature of the coal and that of the associated sediments is type II. Early generated hydrocarbons (exsudatinite) have formed from pollen exines filling the pollen cavities and in places filling micro- fissures in the surrounding vitrinite.

Jan 1, 1987

By Smith Z, Huppert P, Charbucinski J

The paper describes a spectrometric method and apparatus developed for lithology logging in brown coal formations. The nuclear spectromet- ric technique developed is able to delineate coal/sand/clay seams. One requirement was to log inside drilling rods, as well as cased or open holes. The method described is based on combined natural gamma and gamma- gamma techniques using a spectrometric system for signal acquisition and subsequent computer based on-line data analysis and interpretation.

Jan 1, 1989

This is the time of year tor the presidential address, and with the present incumbent engaged in the coal mining industry, it will therefore come as no surprise to you that the theme of my address this evening is concerned with coal.There are other reasons for this apart from my contact with the coal industry. At present, coal is supplying considerable overseas revenue at a time when the remainder of the mining market is in a somewhat depressed state. That times will change goes without saying, if history is to be believed.However, so far so good for coal. My first reaction when The Institute indicated its wish that I be president for 1976 was to become deeply conscious of the honour bestowed on me.On consideration, I realized that very few past presidents have been intimately connected with the coal mining industry to the extent of indulging in it for lengthy periods as a full time occupation or, conversely, a part time interest for a long time. It also appears that not one had started their career in the industry. In my case, 'also, there were 8 very interesting years ,as a gold miner and metallurgist before commencing in coal.It therefore seemed appropriate to endeavour to discover ,why this should be so, as coal mining is now a very important part of a very important industry. What were the reasons why the industry took so long to emerge when there were ample reserves of easily accessible coal?Frankie and Johnnie in their bar room epic of the depression years concluded, and I paraphrase, that "their story held no moral, their story told no tale". If my story has such a message, it could perhapsbe construed as reinforcing the oft-repeated dictums, true or false, that "history repeats itself" or "man never learns".Coal mining is by far our oldest major Australian industry except for agriculture. Its history is almost as old as that of settlement:For various reasons, there has been a glamour associated with metal mining ventures which prob...

Jan 1, 1976

There is no other effective way for study ing firedamp and coaldust explosions than to produce controlled explosions in a pre-monitor- ed environment - either mine openings kept for the purpose, or special surface galleries. Such explosion testing facilities have been employed historically at Buxton in U.K., with lesser known installations at Bruceton, U.S.A., Tremonia, West Germany, Katowice-Mikolow, Poland and elsewhere. Both firedamp and coal dust explosions are studied. Normally coal dust explosions are initiated by somewhat standardised methane air mixtures, by explosives, or purely by coal dust. Various structures and suppression installations are installed in roadways and galleries prior to explosion to simulate destruction and suppression, and the results of such tests form the basis of suppression installations, especially stone dust barriers and water barriers. Other data collected from these experiments include rev- ersals of explosion waves, pressures and temperatures and duration of explosion waves, analyses of aftergases etc. Other uses of explosion testing galleries include testing of explosives, electrical equipment and frictional . sparking.

Jan 1, 1981

By Feebrey CA, Duncan RA

The Ebor Volcano in northeastern New South Wales is an eroded example of a central-type intraplate volcanic-intrusive complex. It is of Miocene age (19-20 Ma) and has similarities to other central-type volcanoes in eastern Australia which may represent manifestations of sub-lithospheric hotspot activity. Thick lava flows are exposed around the Great Escarpment and are dominated by a tholeiitic basaltic suite, ranging from ol-tholeiite to qz-tholeiite to icelandite with ages of 19.2-19.6 Ma. On its western edge, the tholeiitic lava suite probably overlies remnants of basanite flows belonging to the Eocene (-48 Ma) Doughboy province, but elsewhere, minor alkaline basaltic lavas may be coeval with the tholeiitic suite. Several felsic bodies were emplaced into the volcano at -19.0-19.2 Ma and include subalkaline and peralkaline types. The Crescent Complex is a Miocene-age, strongly differentiated mafic to felsic intrusion in basement rocks and centrally located in pre-erosion reconstructions of the Ebor Volcano. It is interpreted to be a major feeder for the tholeiitic lavas based on age and composition. Evolution of the dominant tholeiitic suite proceeded from a parental ol-tholeiite magma, through qz-tholeiite, icelandite and small volumes of felsic rocks by fractionation of plagioclase, olivine, clinopyroxene and titanomagnetite, accompanied by enrichment of SiO2, F,FeO/MgO, alkalies and HFSE.

Jan 1, 1995

By Little T. N

The Western Australian School of Mines is continuing to investigate the blasting techniques and mining strategies that are used for ore/waste separation (or high grade/low grade ore separation) or to prevent ore and waste mixing. The aim of all the mining strategies is to produce an optimum product. The optimum product is one which contains no diluent and undergoes no mixing of the various identified ore and waste blocks and is fully recovered at the minimum overall operating cost. The current study includes the use of computerised Knowledge Based Systems (KBS) technology to assist the user with the blast technique selection and blast design process. These aspects are highly dependent on the geology. (geometry, rock mass properties, grade distribution), explosive performance and the expectations of the mining company in terms of production rates and equipment utilisation. Most of these factors are not well defined and nor are they easy to quantify. However, a large amount of knowledge does exist and is available in the following forms: rules of thumb, empirical formulae, engineering judgement and past experience. KBS techniques are well adapted to handle such"forms of knowledge. The primary objective of this paper is to illustrate an approach for the use of Knowledge Based Systems during the analysis and interpretation stages of the blast design process. In particular, the components and methodology of the developed system are described for selective open pit gold mining. The Knowledge Based System developed was written using the declarative programming language PROLOG.

Jan 1, 1990

With the recent increase in the number of underground secondary sulphide dust explosions in Canada, Australia and elsewhere in massive sulphide ore mining industry, establishment of quantitative and realistic methods of analyzing the mine dust is of paramount importance. This paper examines and analyses dust samples from a mine area that has very recently experienced sulphide dust explosions. Also, it attempts to evaluate the physical and chemical characteristics of the dust. Explosibility of the dust samples was determined by quantifying the oxidation reaction of the sulphide dust particles in a 1.2 L, Lindenberg open horizontal tube furnace. Percentage sulphur', % S oxidised during ignition of a dust sample of known assay, % S and dust concentration (g/m3) were determined by the quantitative chemical analysis of SO2 gas produced during the oxidation reaction. A dust sample with high sulphur content, 22.3% S (assayed) and mean particle size 9.82 pm, was found to exhibit a low degree of oxidation compared with a sample of low sulphur content, 15.44% S and mean particle size 21.7 tcm, at the same Temperature.

Jan 1, 1988