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Recent exploratory work has greatly enlarged our knowledge of the geology of the sedimentary basins of Western Australia. The most pros-pective of these for oil explorati on are believed to be the Canning, Carnarvon, 'and Perth Basins.The search for oil. in, the Canning Basin has fora the most part been concentrated in" the western part, where four main structural units are now recognized - the Lennard Shelf, Fitzroy Trough, Jurgurra Terrace, and-South Cariizin.g Basin. Of these the Leonard Shelf may. be the'most prospective. The principal objective on the Shelf is the Devonian sequence, which in-cludes well'developed reef complexes. The Lower Carboniferous is regarded., as a further objective, as it contained small quantities of oil in theMeda No. I well.In the. Carnarvon Basin most explorati on has been conducted in the coastal belt of'Tertiary folding, especially in the Cape Range-Rough Range area. -The discovery of oil in the first test well. drilled.in the-basin - Rough Range no. 1 - raised great hopes, for the quick discovery of a ecmuercial field. However the other wells on Rough Range have been dry, and no discoveries have-been made in the-wells drilled on other anticlines.in the basin.

Jan 1, 1962

By Huber A. L

Research and development into alternate gold and precious metals adsorbents has resulted in the development of a new technology named the AUROSAVE adsorption process (ARGOSAVE'" for high silver con- tent ores). Adsorbents called VITROKELE'" can be tailored for either Gold I (cyanide leach) or Gold III (halide leach) applications. VITROKELE consists of a chemically synthetic adsorbent carried on an inert substrate, often a polystyrene bead. It is suitable for both in- pulp and in-solution use. VITROKELE adsorbent offers certain advan- tages over both carbon and ion exchange resin adsorbents. This paper describes testwork on Australian ores and commercial solu- tions obtained from operating Australian plants demonstrating the kinetic loading characteristics, elution methods and other operating parameters of VITROKELE adsorbent in the cyanide system. Brief reference is made to VITROKELE in the Gold III system.

Jan 1, 1988

Feasibility studies in the development of mining projects are fundamental to most investment decisions. It is important that the issues addressed and the degree of detail involved in feasibility studies are consistent with the investment decisions to be taken. Emphasis should be placed on a thorough analysis of critical project parameters prior to detailed investigations being undertaken into other activities which are not relevant to the decisions at hand. Therefore, the issues to be decided upon should be influenced significantly by the stage of development of the project and by the reliability of technical and financial information used in the study. Some of the more critical parameters of feasibility studies are commodity prices, inflation rates and discount rates. Advice is given on the selection of these inputs and also on their application in the feasibility study as the project progresses through its various development stages. The feasibility study should involve not only a formal evaluation of project economics but also an analysis of all project related risks and a comparative analysis of projects competing in

Jan 1, 1983

Mining companies around the world devote considerable effort to production reconciliation and metallurgical accounting. However, although sampling, weighing and analysis methods used to obtain the raw data for metal balancing continue to improve, they are still areas that are sadly neglected. Using the latest metallurgical accounting package to improve metal balancing is fundamentally flawed if the data used are unreliable in the first place. The basic rule for correct sampling is that all parts of the material being sampled must have an equal probability of being collected and becoming part of the final sample for analysis. If this rule is not respected, sampling bias can easily be introduced. Unlike precision, which can be improved by replication, bias cannot be reduced once it is present. Sampling and sample processing procedures must therefore be carefully designed both to minimise bias and to obtain acceptable precision. The most suitable sampling location is the discharge point of a process stream, where increments can be obtained by taking a complete cross-section of the stream with a sample cutter. Sampling devices that take only part of the stream may introduce serious bias and must be avoided. The moisture content and wet mass of the material being sampled are of similar importance to chemical analyses for determining metal content. The accurate determination of moisture content is particularly difficult, because the moisture content of samples can change after the sample is taken, eg due to moisture evaporation. Hence, moisture samples need to be taken quickly and placed in sealed bags or containers that are impervious to moisture. The moisture content should then be determined without delay. To determine wet mass, a range of weighing methods are used in industry, including weighbins, weighbridges, conveyor weightometers and platform scales. The precision and accuracy of these methods vary considerably, so it is important to select a method with the appropriate precision and ensure that the weighscale is well maintained and regularly calibrated.

Jan 1, 2002

By Restarick CJ

Plant data are presented which indicate a relationship between flotation rate constants and pulp density in zinc cleaning circuits at Broken Hill. The data were obtained from down the bank sampling of cleaner and recleaner banks at North Broken Hill and New Broken Hill Consolidated Concentrators. It was found that, under normal plant operation, flotation rate constants increased at the lower pulp densities existing in the later cells of cleaner banks. The addition of dilution water to the feed to the bank increased flotation rate constants, thereby confirming the relationship. It is shown that the relationship between flotation rate constant and pulp density is size dependent, being most pronounced for larger sized particles. In contrast, the effect is not markedly dependent upon mineral type. Possible consequences of this relationship for control of cleaner operation are discussed with the aid of some simulated results.

Jan 1, 1978

By J A. Brown

Osborne Mine commenced hydraulic filling of three stopes in April 1999. Two of these stopes experienced barricade failures in July 1999 and January 2000. As a result, a review of hydraulic filling was commissioned in April 2000. The design of a trial of revised specifications and practices is in the final stages, prior to the trial commencing in mid-2002.

Jan 1, 2002

There has been a significant increase in exploration and development of mineral wealth in South East Asia over the past five years. This paper describes the foreign investment laws in the region as they relate to the mining industry.

Jan 1, 1993

By Walker V

The 'MAGNADET' to provide a safe enhanced protection extraneous currents, electricity and radiodetonator was designed electric detonator with against the effects of current leakage, static frequency energy.It has found a particular niche in shaft sinking operations and Mount Isa Mines initiated trials of the system in 1983 as part of the design work for the 3000/3500 orebody access shaft.Initial surface blasts indicated a number of significant advantages which were confirmed during the bench and concrete phase of the M37 shaft sink. The application of 'MAGNADETS' was later extended to the horadiam phase of the project.Details of the exploder capacity calculations for the various M37 round designs are included with the paper.

Jan 1, 1985

By C Rogers

"The Coal Seam Gas (CSG) industry has seen a rapid increase in activity over a 30-year periodfrom the early 1990s within Australia. Despite public concerns over environmental issues, theCSG industry has increased in Queensland to the point where more than 90 per cent of naturalgas consumed in Queensland is CSG. The New South Wales (NSW) CSG industry has been slowerto respond for many reasons. Ninety-five per cent of natural gas consumed in NSW comes frominterstate. However, CSG activity in New South Wales is increasing notwithstanding publicconcerns. The CSG potential of three Petroleum Exploration Licenses (PELs) are being assessedwithin the Southern Sydney Basin that provides a unique opportunity to develop resourcesstrategically around many abandoned coal mines. The question has been asked - what do theseabandoned coal mines mean to the project? Are they good or bad? Are they friend or foe? Thispaper att empts to answer these questions and in doing so describes the coal mine ventilation andgas management philosophies and practices used to assess gas production potential. The coalmining philosophies not only have the potential to assist in the construction of a highly successfulCSG project, but they also potentially add signifi cant pre production value by re defi ning how theresources and reserves are assessed and therefore valued. The behaviour of abandoned coal minesand the goaves within the PELs are not well understood by the petroleum industry. However, in the Illawarra region there is an abundance of coal mining knowledge and expertise that if properly focused can greatly increase the chances of project success."

Jun 1, 2012

By G Steward

Gravity Leaching of high-grade gravity gold concentrates, such as Knelson Concentrates, with the ACACIA Reactor represents a new generation of concentrate treatment methods. The ACACIA Reactor is a complete packaged plant for the maximising of gold recoveries from gravity gold concentrates. This paper will introduce the process technology and provide process results from the Porgera ACACIA Reactor installation. The advantages of the ACACIA Reactor are many, and justification for installation has been varied. The typical advantages of the process include: increased recovery of gold from the Knelson Concentrate; no return of high-grade table tails, often grading several thousand g/t, into the mill circuit; reduction in tails grades of slow leaching gold; reduction in the requirement for operating staff by the removal of the manual tabling process and replacing with a fully automated treatment system; improved security by removing the tabling step where operating staff come into direct contact with visible gold; improved health and safety, by the removal of the treatment steps for the table concentrate, which often include operators handling corrosive chemicals and the production of sulphur and arsenic compound fumes; and improved metallurgical accounting, by allowing daily head grade calculations. The ACACIA Reactor was developed by Anglogold for Union ReefÆs Gold Plant and has been in production for over two years, and has proven to be a low cost, high recovery, mechanically reliable method for the processing of gold concentrates. Such has been the success of the plant, there are now four full installations of the processing plant, including Anglogold Union ReefÆs, Anglogold Sunrise Dam, PACMIN Carosue Dam and Porgera Joint Venture.

Jan 1, 2002

By M Surtees

The Limpopo region in southern Africa is considered to be a favourable target for the discovery of base and precious metal mineral deposits. The integration of gravity, geomagnetic, LANDSAT data and geotectonic history is used to formulate an ore deposit model which can be used in the implementation of mineral exploration programmes. Field work was carried out to test and refine the model.

Jan 1, 1993

The financing of mineral ventures is usually supported by the valuation of a mineral asset, the physical size and composition of which have been determined within quantified limits of accuracy in order that the lending or investment risk can be assessed. The Resource or Ore Reserve estimation is the measurement of that asset and may be the outcome of complicated processes of interpretation and estimation requiring an extensive knowledge and understanding of the general nature of ore occurrences, and of the particular deposit under review. In arriving at an interpretation of the nature and physical distribution of minerals in a deposit, observations may only be available from widely spaced samples and geological knowledge and principles are of prime importance. Consultants may be asked by the lending or investing body to "provide comfort" on the quality of the Resource or Reserve estimations and providing such comfort casts substantial obligations of diligence on the consultant.

Jan 1, 1990

Anyone who has driven backwards using only their rear view mirrors knows how difficult it is to avoid spinning the steering wheel the wrong way. So why run your mine that way? Traditionally Reconciliation has focused on the past performance of the mine. In this paper we make a case for Prognostication û the act of forecasting or predicting something in the future from present indications or signs. Reconciliation is a common activity carried out at most mines around the world. Countless geologists and engineers spend hours poised in front of spreadsheets diligently comparing how their resource/reserve model, grade control, and survey pick ups compare to what was actually produced. The result is usually a group of factors, which are applied to future estimates in an attempt to better predict how the operation may perform. Unfortunately, if the road ahead isnÆt the same as what you have just been down, youÆll be æoff-roadingÆ in no time! An alternative is to constantly collect and analyse key measurements that are used to calibrate critical estimates in an iterative process. When variations occur, they are analysed and corrective action is taken to ensure the estimates and measurements realign. In this way the estimates become forecasts and can then form the basis for decision making to ensure that what does happen in the future will match the plan or schedule. By automating this process, some mines have been able to be proactive on a daily basis in order to improve the overall performance of the operation. This paper outlines the key estimates and measurements used for reconciliation, details the characteristics of an automated web based information management system to facilitate the process and provides some insights about how mining operations might move beyond reconciliation.

Jan 1, 2003

By Dunne R, Defilippi J

Dump leaching began at Teller in late-1988 at a rate of 4 MTPA and has been progressively expanded to the present rate of 10 MTPA. Teller's on-going commitment to dump leaching is driven by the amenability of gold ores to the process and the availability of large tonnages of low grade gold ore. The sequence of evaluating ores for dump leaching involves rolling bottle tests on coarsely ground ore, followed by small and large column leaching and finally trial heaps. Trial heap tests are very expensive and an alternative approach to this is large diameter column leaching.A four-column permanent facility was built at Teller to specifically evaluate the leaching characteristics of new dump leach ores. Details of construction, operation and dismantling are discussed in the paper. Capital cost for the four column facility was some $45 940, while operating costs are about $24 800 per column.

Jan 1, 1992

Carbonate replacement tin deposits in the areas studiedhere are genetically related to biotite granites. Biotite in the granites is distinguished by distinctive compositional features. High MgO content is found in biotite in the Renison Bell granite; high MnO and A1203 contents in the Gejiu granite; and high FeO content in the Xinlu granite. The compositional features of biotite in the granites are reflected in skarn minerals formed around the granites.Granites associated with these tin deposits are characterized by different accessory minerals. Magnetite-bearing granite in the Xinlu deposit is related to the andraditic garnet (andradite 40-45 mole%)-hedenbergite skarn, with tin mineralization occurring in the contact skarn only. The sphene-bearing granite in the Gejiu deposit is related to the grossular garnet (grossular 50-60 mole%, almandine 20-30 mole%) -salite skarn, with tin mineralization occurring in the contact skarn, as well as stratabound replacement orebodies in the distal skarn. The ilmenite-bearing granite in the Dachang deposit and the Renison Bell deposit is related to the grossular-diopside skam, with tin mineralization occurring 500-1500 metres vertically and 1.5-3 km horizontally away from the granite contact.

Jan 1, 1990

By Sorokin M. L, Komkov A. A

Flash smelting of nickel sulphide concentrate has been practiced at WMC's Kalgoorlie Nickel Smelter for 20 years. The mineralogy of the concentrate from the original mines was particularly suited to this process. However, taking a strategic view, potential new processing routes should be fully evaluated as possible replacements for the current technology. The Vanyukov process has been under development in Russia for the past 40 years and has been successfully applied on a large scale to the smelting of copper concentrates, at two locations - Norilsk and Balkhash. The potential for the application of the Vanyukov process to the smelting of nickel concentrates offers a number of processing advantages, including smaller reactor and decreased dependence on fuel oil. This paper reports on preliminary investigations into the application of the Vanyukov process to the smelting of nickel concentrates. At this stage the investigations are limited to semi-quantitative comparisons and modelling studies.

Jan 1, 1992

By H R. Phillips

The ventilation and refrigeration design of underground mines is an important aspect, when new or existing mines are considered and places a great responsibility on engineers tasked to do so. The current trend for both local and international underground mines is to extend their search for valuable ore reserves deeper below surface. In South Africa, the predictions are that about 40 kt of actual gold still lies in situ, ready for extraction. As mines extend their search for minerals of economic value deeper and deeper into the earthÆs crust, ventilation and refrigeration aspects of such mines become more prominent than before. The planning and design of the required ventilation and refrigeration within these mines, over their expected lifetime is important including the practical implications of such designs. Technology changes and improvements need to be incorporated into ventilation and refrigeration designs, where possible and advances in this specialised field explored. This paper explores ventilation and refrigeration design aspects within the underground mine sphere. Aspects such as mining depth, virgin rock temperature (VRT), mining methods, and different cooling applications available including ventilation supply are reviewed in design applications. Heat generally becomes a significant aspect to counter in these mines and they are not always necessarily deep mines.

Jan 1, 2005

Comalco Aluminium Limited uses a computer system for cost, supply and maintenance reporting and control at its bauxite mine in Weipa, North Queensland. The system collects data on a daily basis at a high level of detail on both cost and maintenance history. This allows useful reporting to all levels of management from the shop floor to the General Manager. The most successful aspect of the system is that the information is available in all workshops on visual display units. This allows the real spenders of the Company's money, Foremen and Tradesmen, to make well informed decisions. The system has also decreased the time taken to find parts and information which gives the Foremana greater opportunity to do his real job of supervision and quality control.

Jan 1, 1983

A vigorous seismic and drilling programme has been conducted over.ar area of .59000 square miles in the Roma district during the last three years. The work is Mill' in progress and although many new geological concepts have been discovered, he subsurface geology is not yet finalised. D.atailed examination has shown many variations of .section, has established the general basement trends and sedimentary thicknesses, has shown that much more of the section is marine than previously thought ~nd has indicated that any reservoirs throughout the section could be potential oil ind/or gas producers if suitable traps are located.

Jan 1, 1962

A brief introduction is given of the scale and of some special features of South African gold mining; it is noted that great depth of mining and narrowness of the reefs, and hardness and abrasiveness of the rock are the main sources of the problems of the industry. The most inhibiting problems are: Excessive rock pressure occcurring in conjunction with rockbursts, hot and humid working places due to high virgin rock temperature and auto-compression of the air, and low level of productivity. Conventional solutions applied ordinarily in mining do not promise to eliminate, or even alleviate, these difficulties.

Jan 1, 1985