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By J Cook, S Pike, D Pridmore

"An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation. The application of high-resolution seismic reflection to map structure and/or mineralisation in hard rock environments has progressed significantly in the last decade. Improvements in equipment, field practice, processing and understanding has seen the seismic reflection technique emerge as a cost-effective tool for high-resolution three-dimensional structural and lithology mapping to depths far greater and with superior accuracy than other more conventional geophysical techniques.This paper outlines results and preliminary interpretation of 2D and 3D seismic reflection surveys aimed at defining fault zones and locations for quartz load development in favourable host lithologies at the Cracow low-sulfidation epithermal gold system in Queensland, Australia.As this is possibly the first time that high-resolution seismic reflection data has been used to define the structurally-controlled location of low-sulfidation epithermal gold mineralisation, an important aspect of this work was the derisking or due diligence steps taken prior to commissioning the full 3D surveys at each site. This included full wave sonic logging, vertical seismic profiling and trial 2D lines. Interpretation of the 2D profiles and the drilling of interpreted structure provided the confidence to proceed with the full 3D survey.The advantage of collecting 3D data extends beyond ensuring that the received reflections are located correctly in 3D space. The final 3D data cube can potentially map the entire fault network, thus highlighting flexures and changes in orientation of the structures both vertically and along strike, which is an important aspect in the deposition of gold and for direct targeting.CITATION:Smith, R, Cook, J, Pike, S and Pridmore, D, 2015. Application of high-resolution seismic reflection surveys to exploration for blind vein systems at the Cracow low-sulfidation epithermal field, in Proceedings PACRIM 2015 Congress, pp 77–84 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 18, 2015

Water resources legislation in Brazil is evolving in a number ways. The nature of water resource ownership has changed in the last constitution (1988) so that now all water remains the property of the state and not the individual. There is also an increasing amount of legislation to control water access from the environment and regulation over water quality for water discharged. Finally, in some regions charging for water has been introduced and this is expected to become more wide-spread over the next few years. Increasing government attention to water legislation creates an increased need for mine sites to improve water management. As a fundamental basis for this, it is necessary to make robust estimates of mine site water balances, which also requires knowledge of the regional water balance to provide context for the mine water use. A conceptual model for mine site and environmental water balance is presented. Issues associated with conventional water monitoring are discussed. It is proposed that introduction of automated monitoring to provide comprehensive and consistent data is attractive. However, there remain a number of cultural and practical impediments to purchase, implementation and maintenance of effective monitoring, which are summarised.

Jan 1, 2009

By Millett R

In January 1989, Western Mining Corporation (WMC) acquired the Perseverance and Rocky's Reward orebodies and associated infrastructure from the Agnew Mining Company (AMC). AMC had closed the operation in August 1986 and it had been on care and maintenance since that time. To return the operation to full production as quickly as possible it was planned to mine the Rocky's Reward orebody by opencut mining and treat this ore whilst the underground Perseverance workings were rehabilitated. Removal of overburden from Rocky's Reward thus commenced immediately with a target of April 1989 for delivery of the first ore to the concentrator. Extensive rehabilitation and upgrading of the concentrator commenced in late January, and continued in stages for an 18 month period. The first stage consisted of overhauling all existing equipment and completing a crusher upgrade commenced by AMC prior to the mine closure. During this period, it was necessary to recruit a workforce and re-establish all the required support structure. In late April the plant commenced commissioning trials on mullock. The first ore was crushed on the 11th May 1989 and concentrate produced the following day. From May 1989 to June 1990 the plant was producing nickel concentrate whilst further upgrading continued. During this period, the flotation capacity was tripled by installation of a bank of eight Wemco 144L flotation cells in rougher-scavenger duties and two 12 metre by 2 metre diameter columns in cleaning duties. The existing vacuum drum filters were replaced by two Larox PF32 pressure filters, eliminating the need for solar drying and allowing the flash drier to be fed direct from the filters. These, along with a major borefield expansion and further work to the crusher increased the nominal plant capacity from 600,000 to 1,000,000 t/yr. The plant achieved the 1,000,000 t/yr rate in April 1990.

Jan 1, 1991

By Ward S. C, Gardner J. H

In 1990, Alcoa of Australia Limited was elected to the Global 500 Roll of Honour of the United Nations Environment Program for the environmental management and rehabilitation of the bauxite mines in Western Australia. This award placed Alcoa in the international best practice category. The story of constant improvement spans more than 20 years from a 'trial and error' start to a strategically focussed and research driven program today. The main driving force has come from within the company, against a set of strong corporate values and a well publicised Vision based on 'excellence through quality'. Along the way public opinion, action group protests, increased legislative controls together with the professional competence of internal and external environmental resources have all played a part in arriving at the level of current environmental management and mine rehabilitation performance. There were numerous lessons learned here during the evolution and maintenance of best practice. These included: I . To work diligently in obtaining a vision or strategic intent on mine site rehabilitation and environmental management - don't be easily dissuaded.

Jan 1, 1995

By Dharmappa HB, Sivakumar M

This paper is concerned with two case histories of wastewater quality management in underground coal mines in the Illawarra region. The first investigation briefly presents an analysis of mine water discharge having an extremely high concentration of suspended solids and consistently high barium concentrations, averaging, 14.4 mg/I Barium, over the sampling period. A laboratory study of chemical precipitation processes has indicated that about 91% of barium could be removed by using ferric sulphate and lime. On the basis of the information obtained from the environmental audit process an alternative water treatment and reuse system incorporating 51% reduction in the water consumption with 32% less off-site discharge has been suggested (Thomas, 1995).The second case history is concerned with the storm water management at a mine situated in the Illawarra escarpment where only 20% of the wastewater generated in the colliery is discharged off-site. Computer modelling of the storm water system showed that 75% of the clean runoff becomes contaminated through poor management practices and causes the process wastewater treatment system to fail in wet weather. Suggested improvements include relatively simple alteration to the coal wash filtration dams which are expected to reduce the periods of inefficient operation of these dams by 95%. The use of storm water diversion channels and detention basins can reduce the overflow volumes by 70 - 100 % for a ten year ARI (Average Recurrence Interval) storm event (Wingrove 1996).

Jan 1, 1998

By S Blackburn, T Veasey

The physical and mechanical properties of rock can be measured by a variety of standard tests, and studies have shown that there should be a fundamental connection between breakage in comminution and rock æstrengthÆ. The current study aims to develop the ring-loaded strength test, used as an industry standard for the characterisation of brittle ceramics, for determination of comminution behaviour from exploration borehole core samples. The test procedure is simple, reproducible and can yield 250 separate measurements from a one metre length of drill core. The effects of material grain size and fabric on the degree of scatter of results have been investigated with respect to the ring-loaded strength test. This study has also compared the ring loaded strength to the chevron bend test used to determine the Mode I fracture toughness. A wide range of rock materials have been studied and with further work it is conceivable that an operational work index could be obtained directly from exploration drill cores tested via the ring-loaded disc test.

Jan 1, 2000

By Moore R

An intensive safety campaign at Mount Isa Mines Limited from 1956 to 1966 saw the lost time accident frequency rate fall to half its original level. A review of the safety programme was carried out in 1967 and in 1968 the Five Point Safety System was introduced. The seven years since its introduction have been years of significant achievement both in production and safety. Improving safety is a fundamental part of Mount Isa Mines Limited's policy and this system has been a major tool in implementing that policy. To be successful personnel need to be prepared and trained for its introduction and subsequently counselled on its use. A carefully prepared programme is required to phase in various aspects of the system and to make use of complementary steps. The system has been a success and it is anticipated that the continued drive to improve the use of principles of the system will further improve safety. It is hoped that this paper will be of value to those personnel concerned with industrial safety in Australia.

Jan 1, 1975

By Fyodorov A. N, Sorokin M. L, Komkov A. A

The Vanyukov Process is a bath smelting technology, that has been investigated for over 25 years and since 1977 has been in use on an industrial scale. Results of trials that have been carried out at the various pilot facilities over the past 15 years are considered in this paper. Both the main process aspects, design of the pilot furnaces and metal distributions are presented for consideration. Experience of the smelting of copper, copper-nickel, copper-zinc, nickel, lead, and pyrite concentrates is analysed.

Jan 1, 1992

By Andrews S. J

Century is a shale hosted zinc, lead, silver deposit developed within gently folded, Proterozoic Lawn Hill Formation shales and siltstones, approximately 250 kilometres north-northwest of Mount Isa, comprising 118 million tonnes of stratiform mineralisation, averaging 10.2 per cent ,,inc, 1.5 per cent lead and 36 grams per tonne silver. The deposit is largely overlain by Cambrian limestone and younger Proterozoic sedimentary rocks, outcropping at only two places. Small discordant lode lead-silver deposits formed the basis of relatively small scale mining activity in the area for almost 100 years, exploration tenement covering the deposit being granted to CRAE exactly 100 years after the first mining leases were pegged in the area in 1887.Stratiform mineralisation occurs within three distinct blocks, bounded by normal faults and the unconformity between Lawn Hill Formation and overlying Cambrian limestones. The Termite Range Fault, a major northwest trending, regional scale fault system occurs adjacent to the northeast deposit boundary, while the Magazine Hill Fault, possibly a component of the east trending Little Range Fault system, forms the southern boundary of the deposit.

Jan 1, 1993

By Dight P. M, Dugan K. J

Design approaches for the artificial support of open pit walls have been reviewed and the main factors affecting support performance have been identified. An example of passive support in a potentially unstable pit wall has been used to demonstrate the importance of slope displacement as part of the support design process.

Jan 1, 1989

The safety culture in mining has progressed towards a zero tolerance of injury. This change has required that some historically inherent risks of mining are engineered out or reduced. One of the significant causes of fatality in Western Australia and Worldwide mining is through rock fall, subsidence and inrush. Efforts put into understanding the material properties of the ground we mine and the backfill we place are reflected in improved safety statistics. It is no longer acceptable to not manage these risks and mining, to be sustainable, has to be safe.   Mining historically produced waste products with little consideration of recycling or impact on the surrounding land. The rehabilitation of mining waste products such as mill tailings, heap leach and waste rock is one step towards managing the environmental impact of these waste products. A better step is towards recycling and redepositing these products to produce a more environmentally sustainable mine site.   Gold fields St Ives lease is an active network of new and historic undergrounds and open pits within the Lake Lefroy and Kambalda district. The process of creating voids underground followed by open pits mining through the old voids allows the use of backfilling to control inherent hazards and dilution. Backfill provides opportunity for the disposal and recycling of mining waste materials at the same time as meeting requirements of mine support. Materials available on the St Ives site include spent heap leach, reclaimed tailings and waste mullock. Through recycling and re-depositing these materials to St Ives and neighbouring mines, the reliance on imported material to meet their needs and impact on surrounding land is reduced.   At St Ives, paste fill and barricade design have been reworked to allow backfilling into stopes with water inflows up to six litres per second. This has required a rethink of the drainage and monitoring of water management systems previously used for hydraulic fill and apply them to paste.   The St Ives open pits have developed methods to mine through underground workings and individual stope voids up to 62,000m3. Here backfill is used to reduce the consequence of catastrophic, unexpected failure of the crown and minimise ore lost down voids and dilution through increased blast movement. This paper outlines the less common methods being adopted to use the recycled materials and ways it has been managed to suit the needs of the company.

Jun 1, 2010

The growth in the nickel market and the price increases predicted in 1970 have not mat-erialized. Several plants have been construct-ed, particularly to treat lateritic ores. A spectacular increase in cost of energy and the escalation of capital costs have led to severe economic difficulties on the part of many nickel producers. Several of the nickel prod-ucers joined together to form a Nickel Develop-ment Institute in 1984 with the prime objective of improving nickel markets. Most producers have taken exceptional action to cut overall costs as well as unit costs. Another organiz-ation made up of nickel producers, NiPERA, was established in 1980, to study and take action on problems of nickel in the environment and especially in the workplace.Ion exchange, and particularly continuous ion exchange, has been developed into a reli-able commercial unit operation in the last dec-ade. An example of how ion exchange combined with hydrogen reduction can be integrated into a Caron type reduction roast ammonium carbonate leach process for the recovery of nickel from laterites is discussed.

Jan 1, 1985

By Hayes K. M, Ostwald J

Compacted tablets of hematite ore (containing clay and quartz gangue) and limestone were heated in air in an ULVAC-RIKO rapid heating furnace to maximum temperatures in the range 1200-1350°C.The resulting sintered products were examined in terms of mineralogy, texture, strength and reducibility. The sintered tablets are a good analogue of normal plant sinters. These investigations have shown that sinters of optimum reducibility are produced in the narrow temperature range 1250-l275°C. Conditions for the production of such highly reducible sinters under plant conditions are discussed.

Jan 1, 1984

Access roads for haulage, construction or maintenance purposes are discussed with particular attention being given to the un- sealed "all weather" form of construction for Off-Highway applications. The service conditions experienced by the surfaces used in these roads is examined. These conditions are discussed in terms of the conventional engineering properties used for natural gravel material selection. Experience gained during the construction of a pipeline access track is used to illustratE material selection guidelines based on geological input and an understanding of good construction practices. TMITDnIll IrTT Ohl In many Australian situations off-highway haulage by wheel or track supported vehicles is carried on unsealed, gravel roads. Although the unsealed gravel road is the back-bone of the rural road network in Australia, in general, traffic loadings are relatively low compared to the off-highway unsealed haulage road. The cost of the haulage/access road construction component is one important factor in project planning which needs careful consideration. It is no longer acceptable that the initial rough exploration track be gradually upgraded so that it will eventually carry construction and maintenance traffic safely and efficiently. Fatal accidents and

Jan 1, 1982

By J Abols, T Hughes

The selective recovery of gold and silver from solutions containing other metals, such as copper, is possible using AuRIX«100 resin in conjunction with the Gekko Resin Column. Selectivity is driven by controlling the solution pH, which enables activities such as loading copper, gold and silver and then selectively stripping copper before gold and silver. Alternatively gold and silver can be loaded and the copper left in solution. The selective loading of gold while reducing the silver loading has also been demonstrated, opening the possibility of producing high grade gold dorT from high grade silver pregnant leach solutions. This paper reviews the AuRIX«100 resin and Gekko Resin Column Technologies, discusses the uses of AuRIX«100 in the recovery of gold and silver and the chemistry relating to several projects for which AuRIX«100 is being tested.

Jan 1, 2005

By Turner T. M

The problem of metering fine particulate material at low flowrate is often encountered in metallurgical experiment. This note describes a feeder which wa developed to provide metered flows of copper sulphide concentrate in the range of 0'1-0'7 g/min.It is believed that the present device is easier to operate than previously described feeders (e.g. Hamor and Smith, 1971). It may have applications in the field of analytical chemistry, as well as in metallurgical investigations.

Jan 1, 1978

By J-S Zhang

In this paper, the author briefly introduces the resource characteristics of Chinese iron ore, as well as the present increasing market demand for iron concentrate. The SHP-3200 wet high-intensity magnetic separator (HIMS) is used to separate complicated weak-magnetic iron ores being composed of specularite, limonite and siderite in Jiuquan Iron and Steel (Group) Co Ltd. Some technologies have been used to improve SHP-3200 HIMS, including modifying the angle of magnetic polar from 90¦ to 83¦, cooling the exciting coils by oil instead of air, adding reverse-washing equipment to wash off magnetic particles and adjusting the tooth-space of the matrix from 5.0 mm to 3.5 mm or 2.5 mm to enhance the recovery of fine particles. It is still difficult to meet the requirement for recovering more difficultly separated iron and the demands for high-grade concentrate of iron. In order to improve the recovery of difficult-separated iron, the film-magnetic separation technique is applied into the HIMS and a new LY matrix is designed to form magnetic gradient vertically. A flowing-film feeder is also added and the feed mouth is modified to make a slurry flow formed in the form of film along the wall of matrix. The microstructure and dissemination character of the mineral particles is studied, and the specific susceptibility of the primary minerals is measured. Then the distributive characteristics of a magnetic field for the separator with film-magnetic technique and the motion of particles in the process of separation are all analysed. By introducing the film-magnetic separation technique to SHP-Φ700 HIMS, the recovery of iron can be raised from 69.45 per cent to 76.07 - 78.96 per cent with the similar grade of concentrates of iron. Such an increase of 9.51 per cent in the recovery also shows that it is feasible for such film-magnetic separation technique to be applied into HIMS.

Jan 1, 2005

By Leigh J. H

A history is given of the dust control techniques developed and applied by the mining companies at Broken Hill. A history of the regeneration works undertaken since 1936 is out- lined. Particular emphasis is placed on the stabilization of mine residue dumps which are located throughout a belt of mining leases in the middle of the city and which began in 1937. The establishment of vegetation for dust control techniques is discussed in detail and a case study is given of the successful revegetation of the sides of a 650 metre long, 350 metre wide and 35 metre high residue dump.

Jan 1, 1976

By B B. Beamish, M S. Kizil

The processes that take place during the development of a heating are difficult to visualise. Bulk coal self-heating tests at The University of Queensland (UQ) using a two-metre column are providing graphic evidence of the stages that occur during a heating. Data obtained from these tests, both temperature and corresponding off-gas evolution can be transformed into what is effectively a video-replay of the heating event. This is achieved by loading both sets of data into a newly developed animation package called Hotspot. The resulting animation is ideal for spontaneous combustion training purposes as the viewer can readily identify the different hot spot stages and corresponding off-gas signatures. Colour coding of the coal temperature, as the hot spot forms, highlights its location in the coal pile and shows its ability to migrate upwind. An added benefit of the package is that once a mine has been tested in the UQ two-metre column, there is a permanent record of that particular coals performance for mine personnel to view.

Jan 1, 2005

Incompetent ore and country rock have caused stability problems in longhole open stopes. Fully grouted pre-placed cablebolts have reduced these by preventing ground relax- ation and joint dilation to maintain a self supporting rock structure. Larger atope spans can now be opened with the same or smaller pillar. Mining methods are expected to become less dependent on original ground conditions. Effect of spacing, orientation and stress distribution along the cablebolt is not fully understood at this stage and requires more Observation.

Jan 1, 1977