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Government geoscience may be categorised by objective under three headings: Applied Research for Geoscientific Framework Studies, Resource Inventory, and Technical Advice. In Queensland, the Department of Resource Industries is active in all three categories. Under the program-based management system adopted in 1987, three Programs, namely, Geological Survey, Mineral Resources Development, and Energy Resources Development and Utilisation, have geoscience responsibilities.Prime responsibility for geoscience resides with the Geological Survey Program, which provides a geoscientific framework for mineral and energy exploration and the development of the State. Simply stated, the Program goal is to provide geological information when and where it is required. Geological Survey work also encompasses aspects of resource inventory and technical advice, complementing the work of the other two Programs. This role has a 122 year long tradition, for geoscientists of the Geological Survey have been engaged in investigations designed to facilitate the identification and utilisation of the mineral, water and energy resources of Queensland since 1868.

Jan 1, 1990

The effects of changes in sintering bed height, coke fuel, suction and basicity on sinter productivity, physical strength and mineralogy were determined. It was found that, for a given iron ore, there is a narrow -coke range which maximises sinter strength, irrespective of bed height (in the range 300 to 500 mm) or basicity (in the range 1.2 to 2.2). Increases in bed height, at a constant coke level, improved the physical strength of the sinter. Productivity increases were obtained by increasing the sintering suction but, at coke levels other than the optimum, these *ere somewhat offset by the decrease in sinter physical strength. At basicities higher than 1.2 (i.e. 1.6, 1.8 and 2.2) there was a narrowing of'the size range of product sinter, with a decrease in the percentage of top size material, and a decrease in the amount of fines produced. Changes in coke, bed height and basicity exert major effects on sinter mineralogy, while the Nagoya index was mainly influenced by cote and bed height Changes.

Jan 1, 1975

The term "joint venture" lacks any precise legal definition but is typically used to denote a form of legal relationship which is neither a partnership nor a corporation. Nbst joint ventures are contractual relationships which provide for the sharing of mining leases and production facilities and for the sharing of costs, but which enable each joint venturer to carry on his own separate business. The rationale for such relationships is that each participant: retains independent taxation status may independently grant direct security over his interest in the project assets for financing purposes Bankers prefer to lend to incorporated joint ventures (i.e. corporations in which all of the joint venturers are shareholders) but will lend to individual joint venturers provided the joint venture agreement does not imperil their security; i.e. provided there is a "bankable" joint venture. The carpeting objectives of joint venturers and their bankers may be reconciled and unnecessary conflict avoided by the timely inclusion of appropriate provisions in the joint venture agreement before financing negotiations commence.

Jan 1, 1983

By Valery W, Morrell S, Loughlin P, O&apos

Traditionally, blasts in mining operations are designed to prepare the in situ rock mass for excavation and transport without much consideration being given to the downstream comminution processes. Blasting is in fact the first step in a chain

Jan 1, 1998

The originally estimated mine life at Kidston (starting 1984) was 12 years. Through a continuing process of re-evaluation and improvement in the operation and by expanding the geological knowledge in the region, the mine life has been considerably extended. With falling grades and harder ore, the additional reserves have come with increasing risk - not only in an economic sense associated with diminishing profit margins but also operationally, requiring innovative milling technology and geotechnical designs to provide a lower cost environment for continued profitable mine production.

Jan 1, 1994

The West Fork project is located in Reynolds County, Missouri, in the mineralized zone referred to as the Viburnum Trend. The West Fork orebody has a calculated ore re- serve of 13 600 000 tonne (15 000 000 st) con- taining 5.5 per cent lead, 1.2 per cent zinc, and recoverable values of copper and silver. A total of 64 600 tonne (71 200 st) of lead concentrate and 11 300 tonne (12 500 st) of zinc concentrate will be produced annually. The mill was designed to operate at an average capacity of 3450 tonne/day (3800 st/day), based on a 95 per cent availability factor. The mill will operate 24 hours a day, 5 days a week, with maintenance performed, as needed, on weekends. The mine will operate on an identical schedule; but the underground, pri- mary crushing will operate on a six hour/shift, three shift/day schedule. The 1.07m x 1.22m (42in x 48in) jaw crusher will produce a minus 20cm (8 in) material at an average rate of 191 tonne/h (211 st/h). The jaw crusher has almost twice the throughput capacity required, but the decision to install that size of crusher was based on the need to handle over sized rock in the ore.The coarse crushed ore will discharge into a 180 tonne (200 st) skip pocket, which will allow up to a one hour surge capacity prior to hoisting. Hoisted ore will discharge into a 900 tonne (1000 st) storage bin located adjacent to the headframe. The skip pocket and coarse ore silo comprise the total ore storage capacity. The concept of having no intermediate fine ore storage between the secondary crushing and grinding sections was borrowed from the Brushy Creek Mill of St. Joe Minerals, which operates adjacent to the West Fork property. Integration of the secondary crushing and grinding circuits has worked ' successfully for years at the Brushy Creek Mill. The most obvious advantage to eliminating the intermediate fine ore storage is'capital expen- diture savings. The capital expenditure savings include the cost of silos, feeders, and the cost of additional conveyor length and eleva- tion. Savings in operating costs will also be gained, particularly in reduced maintenance costs. Other factors which influenced the decision to eliminate fine ore storage were the simplicity of the secondary crushing sec- tion and the limited area available for con struction of the facility

Jan 1, 1978

A key premise to this paper is that most people involved in the design and implementation of drilling and blasting operations could benefit from a greater understanding of the geological materials, deposits and landforms they are dealing with. The second key ingredient for successful blasting is the concept of blasting objective. Mine operators and blasting contractors must be clear on what drives their costs (blasting leverage) and should formulate blasting objectives and operational targets which help in this regard. Many operators ignore geology descriptors and features apart from the name of the rock and start crudely quantifying the rock mass properties in terms of uniaxial compressive strength, or even worse still as hard or soft. This occurs too early in the design process and not much attention is paid to the geological materials, geological structures and the characteristics of the deposit they intend to excavate. In effect the rock type name and the strength descriptor become the site geology. Furthermore many blasting operators do not formalise their blasting objective, do not set operational targets and do not measure results to the degree required for continuous improvement. In this paper a number of civil, surface mine and underground mine blasting applications are tabulated in terms of typical blasting objectives and common geological materials. A good description of geological materials can convey a lot of useful information for blasting operators if they are able to accommodate this knowledge. In addition a clear statement of the blasting objective and associated operational targets will maximise the likelihood of achieving blast-driven downstream productivity improvements. The æStarting at Both EndsÆ combination is deemed extremely useful for any continuous improvement blasting program.

Jan 1, 1999

By Jiang G

The Chinese Central Government attaches great importance to the development of its coal industry. Besides carrying out the policy of simultaneous development of large, medium and small coalmines,the main strategy is to gradually modernize coal mining areas and coalmines and to increase the output from individual coalfaces. There are particular implications, processes and main experiences of coalmine modernisation in China.Ensuring a coal output of over one M tonne/yr from one coalface is a very complicated system-engineering project which deals with a wide range of problems. The most important measure used for achieving an output of over one M tonne/yr from a single coalface is the analysis of affecting factors on coalface production by means of the theory c reliability. Thus, as far as possible , the production stoppages caused by mechanical equipment failures and other factors are avoided, the equipment recovery rate is increased and the working hours of shearers are extended so as to ensure a high output and high efficiency.

Jan 1, 1991

By Davey P. T, Tsambourakis G

Mineralogical analysis of supergene sulphide ore recovered from areas close to the underground workings at the abandoned Mutooroo (South Australia) mine shows that the original sulphide minerals have undergone substantial alteration. The cause of this alteration is believed to be contact with the highly saline, acidic mine water. The copper is now present as a sulphide that can best be described as a copper- and iron-delicient chalcopyrite, CuxFeyS2, where in most cases x < y. The values of x and y vary from point-to-point within each grain.Leach tests under a variety of conditions show that dissolution of the copper from the supergene sulphide ore can be readily achieved, particularly when compared with the behaviour of Mt Isa chalcopyrite concentrate. For the supergene sulphide ore, an increase in the acidity and the iron(lll) concentration of the leachant re ults in an increase in the rate of copper dissolution.The results are briefly discussed in terms of the experimental in-situ leaching operation at Mutooroo, South Australia.

Jan 1, 1986

It is a commonplace of our industry that prices of most minerals have been historically weak during the 1980s. The International Monetary Fund's index of prices of metals fell 25 per cent between 1980 and 1982, rose slightly in 1983, and has since fallen further. In December last year it was 37 per cent below its 1980 average. The few temporary exceptions to the mineral industry's malaise highlight the excess capacity, which largely explains the weakness of prices. The industry has painfully come to recognise that more satisfactory prices will not be restored until supply capability and demand move back into better balance. Mine capacity was installed in the expectation of much faster growth of demand than has occurred. For a variety of reasons mine and plant closures have been insufficient to restore equilibrium to the market-place. The industry may, therefore, have to resign itself to continued weak prices for some years more, at least by the yardstick of the 1970s. Growth rates of demand have slackened off in line with economic activity, and in response to continuing substitution and technological improvements. To the extent that the recent weakness of oil prices stimulates the industrial countries' activity, demand for non-fuel minerals may grow faster than most forecasters now predict. It is, however, much too early to say how long the weaker oil prices will persist, and even more difficult to estimate their probable effects. In typical post-war business cycles the usual response to recession was to batten down the hatches, and ride out the storm. Sooner or later, and probably sooner, demand resumed its previous trend path, and prices recovered. The market, in effect, bailed mines out of trouble; the more efficient could make attractive pre-tax profits whilst even the poor to mediocre could earn a satisfactory living. Prices rose at least as fast as general inflation, and in the early 1970s much faster. In retrospect those price rises of the early 1970s were historically abnormal but they did not appear so in the prevailing inflationary climate of the time. When the market failed in the early 1980s many of the hardest hit companies looked for scapegoats.

Jan 1, 1986

By Smith DM Jr

Silver deposits, in which silver forms at least fifty percent of the value of the ore, are abundant and large on the east side of the Pacific and are absent in the western Pacific. To determine if this uneven distribution is related to features of consuming plate tectonic boundaries which dominate the metallogeny of the Pacific Rim, the variation of Ag/Au in porphyry copper deposits was used to estimate the relative silver content of magma generated in subduction zones. Porphyry copper provinces with high Ag/Au occur in regions of the eastern Pacific where silver deposits are abundant, suggesting that the distribution of silver deposits is controlled by the relative abun- dance of silver in subducted ocean crust. Ocean crust being subducted in the eastern Pacific is mostly less than 50 million years old in contrast to most ocean crust in the western Pacific which is much older. Enrich- ment of silver in young ocean crust at spread- ing centers may reflect metallogenetic evolution over geologic time. Silver may be transported to the surface in volcanic rocks, and deposits are common where felsic varieties are abundant. The high ,solubility of silver in natural waters provides a natural storage mechanism for silver weath- ered from these rocks and ultimately circulated in near-surface hydrothermal systems where many silver deposits form. The regional distribution of silver deposits is not influenced by discoverability, vertical metal zoning, or regional tectonic style. The effect of igneous differentiation is unclear.

Jan 1, 1987

By I Sheppard, A Hills

This paper describes a multi-lift bench stoping method introduced recently to extract the narrow silver-lead-zinc orebodies at the Isa Lead Mine. Cut-and-fill methods were chief mining methods for the narrow orebodies at the mine over 35 years ago. Benching methods were introduced approximately two decades later, and quickly replacing the cut-and-fill methods. The benching methods had improved both the economy scale and safety of the mining operation. The multi-lift benching method combines a number of bench lifts into a single stope to further improve the operational efficiency. Three stopes in the initial multi-lift benching trials are described.

Jan 1, 2003

By Hutton A. C

Quantitative X-ray diffraction (XRD) analyses using the Rietveld method, a standardless technique for full XRD pattern fitting, showed the mineralogy of the eastern Queensland Tertiary lacustrine oil shale deposits is dominated by detrital cla

Jan 1, 1994

To counter depressed world nickel prices, a continuing effort is being made at Kalgoorlie Nickel Smelter to reduce unit production costs. One major area in which production costs can be reduced is the substitution of coal for fuel oil. Two areas where this has been achieved to bring about a saving are, the addition of coal to flash furnace flux to reduce supplementary fuel oil requirements in flash smelting and the replacement of two oil-fired air preheaters with a coal-fired unit. These actions have resulted in coal replacing 67% of the current fuel oil requirement in flash smelting at the Kalgoorlie .Lckel Smelter.

Jan 1, 1987

By Walraven F, Knott G. G

Using a typical small logging instrument (Neltronic KPD), a natural gamma reference section for part of the Brockman Iron Formation and part of the Mt. McRae Shale has been established in the Newman area. This is compared with the stratigraphic type section of Trendall and Blockley (1968). Folding and faulting are recognised using natural gamma logs. Because of the confidence with which stratigraphic horizons can be identified, less expenditure on diamond and percussion drilling is required to confirm stratigraphic position. Using natural gamma logs as stratigraphic control the apparent thinning of the Banded Iron Formation during iron enrichment is Demonstrated.

Jan 1, 1973

By Grace NC, Lightfoot BW

Small scale trials of the smelting of a copper concentrate in the Sirosmelt submerged lance reactor are described. Pellets of concentrate were dropped into the reactor while injecting air-rich mixtures of oil and air through a lance into a bath of matte overlain by slag. This produced a discardable slag and a matte which was converted in sequential stages in the same reactor to white metal and blister copper. Difficulties were encountered in determining the end points of the converting stages but control techniques were developed to allow successful operations producing blister copper. Deportments of minor constituents of the concentrate to slag, matte,metal and fume for the three stages are reported and possible applications are Discussed.

Jan 1, 1980

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

By Komosa T

The increase in the proportion of sulphide ore treated by the gold mining industry has led to generally higher oxygen requirements. Additions of pure oxygen, hydrogen peroxide and in some cases calcium peroxide, have been proposed as a means of satisfying the oxygen demand and overcoming the problems from reactive sulphides in the ore. Current oxidant addition options and practice are reviewed.Laboratory oxygen demand tests are reported for a suite of ores to show some of the effects of pH and preaeration.Laboratory leach tests at high and low dissolved oxygen levels are reported on two of the ores with higher oxygen demands, and the results are assessed in terms of gold leaching kinetics, ultimate gold extraction, and cyanide requirements.

Jan 1, 1992

South Crofty's ventilation network is large and complex. Of the total exhaust air quantity 40% enters the mine by leakage routes through old workings, this air carries high concentrations of radon gas and results in the mine becoming a classified work place under the Ionising Radiation Regulations 1985. Improvements in the control of the ventilating air and dilution by increased air quantity have reduced the average contamination to aelow-0.2 WL. The major part of the radon originates from ground water inflows and from concentrations of radium within the mine with direct emanation from rock surfaces being negligible. Of 600 kBgs-1 total radon leaving the mine 93% cannot be accounted for from known and accessible sources.

Jan 1, 1988

By Jaczkowski B. M, Cox T. J, Domfeh I. A, Stalker I

Mining and treatment of gold ore in the Ashanti region at Obuasi, Ghana has been continuous for more than 100 years. Earlier production from this world class deposit can be traced far into the history of West Africa's gold trade. As part of a general development and expansion program, Ashanti Goldfields Corporation (Ghana) recently undertook a program to heap leach oxidized near surface ore. Kappes, Cassiday & Associates was given a major role in the design, equipment supply, installation and start-up management of the 3000 tonne/day heap leach. Unusual conditions included a high annual rainfall and an ore which could be characterized as a soft, decomposed, water saturated schist. Production began in March 1990. Startup problems and their solutions are discussed.

Jan 1, 1991