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By A Yame, P J. Pollard, E Atase, J Garu, M Tangwari, D R. Hastings, R W. Smillie

"An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation. The Townsville prospect is situated approximately 4 km north of the Ok Tedi copper-gold mine in Western Province, Papua New Guinea. Drilling in the 1990s delineated a resource of >1 Moz of gold within shallow, skarn breccia-hosted mineralisation associated with quartz-carbonate infill, together with pyrite, chalcopyrite, pyrrhotite, sphalerite, galena, tennantite-tetrahedrite, arsenopyrite, marcasite, and a variety of Au-, Ag- and Bi-telluride minerals. The deepest of these historical holes (TVL034) also intersected copper-gold-silver mineralisation more than 100 m below the gold-rich zone that is associated with calc-silicate skarn breccia. Although copper-gold-silver mineralisation in DDHTVL034 is associated with clinopyroxene-rich skarn, it was also noted that garnet in the skarn breccia became progressively darker in colour with depth, ranging from green at shallow levels to dark red-brown at depth. This indicated that the skarn breccia is zoned, with more proximal garnet skarn at depth possibly indicating an association with porphyry-style copper-gold mineralisation.Based on this skarn zonation model, recent drilling at the Titan prospect, located approximately 500 m south of TVL034, was targeted at potential copper-gold silver mineralisation beneath shallow skarn breccia-hosted gold mineralisation. DDHTVL 081 intersected 46 m at 6.36 g/t Au from 68 m and 80.7 m and 1.67 per cent Cu, 1.27 g/t Au and 20.32 g/t Ag from 184 m. Exploration is now attempting to define the extent of copper-gold-silver mineralisation by defining structural controls on the skarn breccia together with paragenetic and mineral zoning data.CITATION:Smillie, R W, Pollard, P J, Hastings, D R, Yame, A, Tangwari, M, Garu, J and Atase, E, 2015. Exploration of the Townsville Cu-Au-Ag skarn, western province, Papua New Guinea – preliminary observations of paragenesis and zoning, in Proceedings PACRIM 2015 Congress, pp 593–600 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 18, 2015

By Mann T

The use of dolomite as a refractory began in England about 1870 when the basic Bessemer process for the removal of phosphorus from steel was developed by Thomas and Gilchrist.Knowledge of dolomite as a refractory in this country goes back to the early part of this century, at the time when the Hoskins Brothers took over the Lithgow Iron and Steel Works from W. Sandford. The practice then was toimport burned dolomite in casks from England. It is reported that much of the material was powdered when received, but was still serviceable. The earliest. used sources of local stone were in the Bathurst and Mudgee areas of New South Wales, and these dolomites were first used raw. Later, dolomite was burned in cupolas at Havilah near Mudgee, coke being obtained from the South Coast of New South Wales. This plant supplied burned dolomite to the Lithgow steel plant, later to the Australil1n Iron and Steel plant at Port Kembla, and also to the electric steel furnaces at Newcastle, Sydney and Melbourne until the plant was closed down in 1946.The Broken Hill Proprietary Company first obtained its dolomite from George's Plains near Bathurst (this was, really a magnesium limestone) and later from Mount Knowles, a deposit near Mudgee, which was eventually taken over by the CO:plpany in 1918. In 1936 Australian.Iron and Steel acquired from the Southern Portland Cement Company a deposit at Mount Fairy in the Federal...

Jan 1, 1951

By A W. Bewsher, T C. McCu, D B. Mapleson

The Miitel nickel sulfide deposit has been overprinted by a family of late stage structures that have acted as conduits for fluids that have contaminated the orebody with arsenic minerals. This has resulted in highly variable and unpredictable arsenic grades throughout the Miitel orebody. The ore produced from Miitel is processed under a toll-treatment agreement with Western Mining Resources Kambalda Nickel Concentrator. Part of this arrangement includes a financial penalty if monthly average arsenic grades in ore delivered exceed 800 ppm. This constraint has provided an extra challenge to the Miitel mine geologist in addition to daily underground duties. Routine development and stope mapping, close spaced sampling and cross-sectional interpretation were used in building an understanding of the structural controls of arsenic mineralisation and ore repetition at the Miitel nickel mine, and in providing maximum input to mine planning and scheduling. The distribution of structures responsible for arsenic introduction is now well understood from detailed mapping, sampling, and interpretation. By applying these insights to mine scheduling, the operation has successfully managed arsenic levels within the required specifications. Geological mapping has also improved the understanding of the structural complexity of the ore deposit, leading to the addition of ore tonnes and an increased confidence in resource modelling. Regular sampling and tight controls on data quality provided confidence in a strongly skewed arsenic data set. Multiple Indicator Kriging has been used for resource estimation of the arsenic contaminated nickel ore since it allows explicit control of the spatial influence of extreme grades in the positively skewed arsenic sample population. Both the grade control and exploration data sets are used to model the arsenic distribution.

Jan 1, 2003

Truly launched during the 1939-45 war, b¬,osted since by huge increases in demand for food, shelter and manufactures of ill kinds, petrochemicals have rocketed into prominence' all'oVer''th'e world and are accelerating to even greater heights.Manipulation of the hydrocarbons in petroleum or natural gas provides raw materials for a wid.e'variety of plastics, resins, detergents, rubbers, chemical intermediates, fibres and fertilisers. These in. turn.. go into a host of products essential to our way of life.A5 a source of chemicals, petroleum has achieved a high place. because of its abundance, relative.eheapness acid ease "f transport and because it can,be' economically processed.'If a nation's industrial' progress is measured by ' the ' modern yardstick of petrochemical production,'Australia has reasonto be proud, for it now has 1S petrochemical plants worth'156 million, either in operation or under construction.At several locations near Sydney and Melbourne, these plants produce petroleum ethylene, propylene, butadiene and benzene, or convert these building blocks into the three major thermoplastics (polyethylene; polyvinylchloride and polystyrene)-a.nd"S.B.R.synthetic" rubber. "A number bf other imr-ortant petrochemicals, including carbon black, and ammonia, also are made, or-planned...Most petrochemicals find application. in seven principal industries - rubber, fibres, detergents, surface coatings, automotive, agriculture and plastics. They play a .part in many other industries, including mining and metallurgy.In Australia, population growth,.an -incr.easing standard of living, greater industrial activity and the replacement of older materials all should considerably expand the markets for established petrochemical plants and lead to the introduction of new manufactures.Unless thwarted, these positive forces should propel petro-chemicals into a future glittering with promise;' ò 'However, some help for the infant industry seems needed if petrochemicals, while growing with the nation, are to contribute as they can to our national development.

Jan 1, 1962

Characterising the weight percentage of each mineral in base metal ores is an integral part of assessing the quality of an ore in terms of its processing properties. The Rietveld method, which uses X-ray diffraction data, has been applied to routinely quantify the minerals in lead/zinc and copper ores from Mount Isa Mines Limited and supergene copper ores from Ernest Henry Mining as well as their related products from the concentrators. The Rietveld method has been tested by comparing Rietveld mineral data with a standard sample with known mineral weight percentages and comparing Rietveld mineral data with mineral data calculated from elemental assays where the element only exists in one mineral such as lead in galena. Where this latter situation does not occur, the Rietveld method has been checked with both elemental and optical microscope data. In all cases, there is a good correspondence between the Rietveld data and the data it was checked against with absolute differences generally in the range of 0.5 to 3 wt per cent. The Rietveld method generally quantifies all minerals occurring over 1 wt per cent in one analysis and is less expensive and more routine compared to traditional methods such as optical microscope point counting. The Rietveld method can be applied to many stages of the mining cycle such as exploration, feasibility studies, mining, minerals processing and for environmental studies.

Jan 1, 1998

By L Whitbourn, K Yang, P C, E Ramanaidou

The potential of hyperspectral mineral mapping within a mine environment is demonstrated. Central to this capability has been the development of portable or vehicle-mounted, hyperspectral mine face-mapping systems. Data from these systems were used to detect subtle mineralogical variations and map their distribution across rock faces in a fashion that previously was not possible. In one study, the data usability was enhanced by ædrapingÆ the mineralogical determinations over a three-dimensional æmodelÆ of the rock-face. The eventual melding of the spectral mine face-mapping and three-dimensional spatial technologies will result in a new generation of mineralogical and structural information becoming available to mine geologists, engineers and metallurgists. Specific uses for spectrally-derived, mineral mapping data sets could include:ore grade mapping systems based on either direct detection of ore minerals themselves (eg iron and nickel oxides), or mineralogies that may be used as surrogates for ore-grade information (via various alteration minerals) after a suitable orientation survey; detecting mineralogies that have a deleterious effect on milling, metallurgical processing or have occupational health implications (talc, swelling clays, carbonates, asbestos, etc); selective mining and blending by collecting, processing and displaying such mineralogical images in near real-time to monitor ore grade and quality, and allow the separation of ore from waste during loading operations at the mine face; a mineral detection and mapping capability to assist in structural and geotechnical mine planning applications; and an enhanced geological detection and mapping capability for ore mineral species or alteration mineralogies that may be used to vector further mineralisation, update the existing mine ore model, or provide input to assist in the control of autonomous mining equipment. Within the Woodlawn open pit, Fe- and Mg-chlorites and phengitic- micas associated with sulfide mineralisation were detected and mapped. Subsequent studies using a second generation face-mapping system demonstrated the direct detection of ore-grade materials for iron-ore and nickel laterite mining activities. Satisfactory and meaningful results were extracted from data that were collected under a variety of challenging conditions. However, these non-ideal climatic and operational conditions would be expected under most operational situations in a mine environment. Development of a system using artificial illumination, permitting night-time (and eventually underground) operation and elimination of atmospheric absorption effects is underway.

Jan 1, 2006

This work describes preliminary laboratory testwork to study the relative leaching response to cyanidation and thiourea leaching of an oxidised low grade gold ore. The potential of an alternative lixiviant like thiourea to commercial processing of mine dumps is discussed by specific reference to selected case histories. It would appear that on the basis of the available published information, there could well be a case advanced for the acid thiourea leaching of sulphide concentrate tailings being subjected

Jan 1, 1994

The writer had the pleasure of several months' laboratory tests on a metallurgical process for copper ores devised by Mr. W. H. Corbould, Consulting Engineer, North Queensland. Mr. Corbould's research work in this direction commenced somesix years ago, and he eventually succeeded in obtaining a good extraction of copper and a resulting solution practically free from iron and other impurities. The commercial operation of the process was investigated and special machines with novel features were designed. OUTLINE OF THE PROCESS.The process described in detail in the following pages, required for successful application that the ores contain at least the minimum ratio of sulphur to copper, consistent with the production of sulphadising roasting conditions.

Jan 1, 1921

BHP Billiton Olympic Dam produces copper cathode, uranium oxide concentrate and refined gold and silver. The operation is comprised of an underground Mine and Processing Plant and is located 560 km north of Adelaide. Water for the operation is sourced from two wellfields located 120 and 200 km from the operation in the Great Artesian Basin (GAB) at a rate of approximately 36 ML/d. Regulatory drawdown limits were established to protect regional GAB springs and are monitored at compliance bores. Drawdown was predicted in the æOlympic Dam Environmental Impact StudyÆ (Kinhill, 1997); however, pumping at higher volumes may have the potential for increased drawdown resulting in a trend towards the compliance limits. In recent years increased usage of water in the Concentrator and Hydromet sections of the Processing Plant has caused excess process water reporting to the Tailings Retention System (TRS). This has resulted in excessive amounts of liquor ponding on the tailings cells with a potential impact being contamination due to seepage of liquor to groundwater. Effective management of water by the operation is necessary to both reduce GAB drawdown and reduce the amount of liquor on the tailings cells. A site working-group has been established to investigate and pursue opportunities to improve the water use efficiency of the operation. This paper will highlight the issue of water management at Olympic Dam and discuss the various options currently being investigated to improve management of this important resource.

Jan 1, 2006

Iron ore in the Pilbara Region of Western Australia varies in composition giving iron ore a range of densities. An accurate density figure of the material leads to accurate calculations of production throughput. Density studies of two separate iron ore mines were conducted in the Pilbara. Procedures and results are reported here.The Pilbara Region of Western Australia has a number of iron ore operations. Two mines have conducted density studies of their materials. The purpose for the studies was to determine an accurate in situ bulk density that could be applied to volume and tonnage calculations of the operation. It was identified that density was one culprit causing calculation variations. Density is an important figure used to estimate ore reserves, equipment requirements, production rates and indirectly costs and sales revenue. One study was conducted at Rio TintoÆs Robe River Mine based near the town of Pannawonica. Its Mesa J orebody is currently being mined and is a low-grade deposit of goethite and hematite (Burnham, 2003). A separate study was conducted at BHP BillitonÆs Yarrie Mine situated north of Newman and east of Pardoo. Its orebody consists of high grade formed by a supergene enrichment of cherty material and a burial metamorphism to produce hematite (Richardson, 2002). The method used to determine density was by large-scale samples using the pre-mining in situ volume of the material and the weight in tonnes after mining.

Jan 1, 2003

Coal is of tremendous importance for the Czechoslovak econ- omy. The current annual primary energy demand being about 109 million tons of standard fuel (1 ton of standard fuel - 7,000 coal = 29,308 GJ), coal satisfies almost two thirds of our fuel consumption. If compared with the distribution of resources in the world's fuel and energy pattern, the situation in Czechos- lovakia is significantly different, as shown in Fig. I. One of the causes behind the difference is that the Czechoslo- vak oil and natural gas reserves and, hence, their production are insignificant, so that it is necessary to import them. Brown coal will continue to play an important role as a prin- cipal domestic source of primary energy even in the future. While the share of nuclear power is increasing, brown coal represents strategic reserves in the fuel and energy balance.

Jan 1, 1989

By Cousens DR, Benhamou M, French DH

Techniques appropriate to petrographic image analysis are being developed using digitized backscatter electron images of well characterized mineral assemblages obtained from a Cameca scanning electron microprobe. Emphasis is on developing descriptors for size, shape and association of mineral grains as these all convey important information concerning the nature of rocks and the processes that have operated upon them. Processes, for example, that could indicate the proximity of mineralization. For convenience, the work is being carried out on the PDP11/73 host computer of the electron micropt be, although it is recongnized that such a multi-user environment is not appropriate for practical image analysis. The eventual aim is to develop a low-cost microcomputer-based package for quantitative description of mineral textures and rock fabrics as an objective aid to the petrographic analysis of ores and host rocks.

Jan 1, 1989

By R Lau

The fire safety design for road tunnels includes the following aspects: active systems, passive provisions and operational procedures. The active systems include the smoke control system, fire suppression system, detection system and fire fighter’s assistance systems. Passive provisions include escape passages, fire separation and fire resistance systems. The operational procedures refer to fire fighter access, reporting and alerts, evacuation processes and crowd control.Currently, these systems are typically designed by different designers or teams. These systems are intended to work together in a coordinated manner to provide the desired safety outcome. However, in practice, this is not always happening. The fire engineering process is supposed to bring together all these aspects and arrive at an integrated safety system. The fi re engineering process in practice is not integrating the design with the practice or reality and is thus arriving at less than desirably efficient safety systems.The example of design inputs shows how disconnected each system design basis is. The smoke control system design is based on the design fire size. The performance of the smoke control system is to achieve a smoke free environment for a defined space for a particular fire size – the design fire. The fire suppression system – most commonly sprinklers or deluge systems, is designed according to codes and to achieve a certain water discharge rate. The fire detection system is designed to detect temperature rise/rate of rise and perhaps density of smoke. Fire separation is determined to provide a certain period of service – mostly for structural elements. Escape route size and location is determined mostly by code compliance. Evacuation procedures are determined by Authority operational requirements rather than human behaviour.To arrive at an integrated fire safety system, the design basis and performances must be coordinated. An approach using fire scenarios would ensure all systems are designed to a common performance requirement. This paper will discuss how the current design approach outcomes compared with a fire scenario approach. More effective and efficient fire safety systems would require the stake holders to understand the implication of this approach and to embrace this through the fire engineering process.

Mar 8, 2011

The uptake of nickel into the lattice of pyrrhotite,Fel_oS has been studied experimentally in the temperaturerange 200 DC to 760 DC. Nickel from both aqueous solutionsand salt melts diffuses rapidly into the sulphide latticewith ,an accompanying rel~ase of iron into the solution ormelt. The rate of uptake of nickel and its diffusion intothe sulphide lattice have been followed ,by opticalmicroscopy and by analysis with an electron probe microanalyser.Some geological consequences of this phenomenonaffecting the distribution of nickel in rocks associatedwith nickel-iron sulphide ores are discussed.

Jan 1, 1980

By Z W. Orndorff

Excavation through sulfidic geologic materials during construction activities has resulted in acid rock drainage (ARD) related problems at numerous (>40) locations across all five geologic regions of Virginia, USA. Potential acidities ranging from >100 to develop a statewide sulfidic materials risk map; document ARD impacts to soil and water quality and engineered structures; and develop methods to assess site-specific risk potentials within a given highway corridor. A statewide sulfidic materials GIS risk map was developed based upon the state digital geology map which assigned four levels of relative risk to all mapped strata based upon predicted lime requirements and probabilities of encountering highly reactive materials. Non-highway construction activities have also routinely disturbed sulfidic materials, and a recent airport project in northern Virginia resulted in over 150 ha of extremely acidic (pH 45 mg/L) run-off from this site heavily damaged a receiving stream, partially due to the fact that it dissolved the galvanised steel water control structures in stormwater detention basins, leading to direct discharge of run-off and sulfidic sediments. The airport area was treated and revegetated in 2002 with a combination of lime-stabilised biosolids, straw mulch, and acid-tolerant grasses. Water quality in a receiving second-order stream quickly responded to the treatment, but some release of N was also noted as a secondary effect. Collectively, these results point out the importance of accurately assessing the potential for excavation of sulfidic materials in construction environments, and the necessity of developing toxic materials handling strategies similar to those employed in mining environments.

Jan 1, 2003

By D Wallace, H Guo, B Shen

Appropriate management of the ground subsidence induced by coal mining activities is essential. To assess the effectiveness of grout injection for mining subsidence control, time-lapse ground penetrating radar (GPR) imaging data were collected before and after grouting. The pregouting subsurface responses were interpreted to have changed after grout injection. The changes were caused by injecting the grout materials (flyash and water) into the delaminated strata and permeable fracture zones. The largest distance of the observed GPR event changes at the right end of the main profile is 132 m away from the injection borehole. Although the GPR images could not easily tell if the image changes were caused by the injected ashes or the water, it does suggest that the injection materials had been pushed at least 130 m away from the injection borehole. This is consistent with the borehole scan monitoring, which confirmed that the grout has travelled more than 90 m from the injection borehole.

Jan 1, 2006

The, Mount Charlotte orebody contains' 5,000 tons per vertical foot-Of'quartz gold ore at an estimated ore reserve grade of )just 'over' 3 'dwt. per ton, Production from it i.s plan ned at a rate of 1,000 tons per working day during 1964.

Jan 1, 1964

By Smallnone P, Walker B

Mining of the AKI lamproite pipe at the Argyle Diamond Mine (ADM) commenced in 1985. Originally designed to mine ore at a rate of 3.6 Mt per annum, the project has gone through two major plant expansions to a designed production rate of 8.7 Mt

Jan 1, 1998

Pilot plant work has played a major role in the process development and design phase of the Iscor Heavy Minerals project. The pilot plant campaigns have been aimed at three process areas, namely primary beneficiation (wet gravity circuits), heavy mineral separation and ilmenite smelting. A process development structure was put in place, and the various pilot plants designed and built. A number of pilot campaigns were conducted during the project phase since 1995, and most of the key objectives were achieved. Various other valuable ælessonsÆ were learnt, and were incorporated in the full-scale plant designs, or used to change operating philosophies, equipment choices et cetera. The cost and durations of the pilot runs were significant, and an analysis indicated that the major risk and technology area of smelting has contributed more than 70 per cent of the total cost.

Jan 1, 2001

The Burra Burra Aline is in complexly folded Torrensian dolomites and limestones forming the faulted axial region of a major anti cling. The orebody mined was largely of secondary origin and confined between two faults, Kingston's on the west and Tinline's on the east. The orebody occurred at the junction between cherty dolomites and a clastic limestone with a large mass of marble breccia along its western margin. Secondary ore consisted of carbonates and oxides in the breccia and the ore bed and detrital copper minerals deposited. As part of a clastic breccia in sink holes and solution cavities in the dolpthites and ore beds.Primary sulphides occur disseminated in the marble breccia and in stratiform habit in the ore bed. Kingston's so-called 'Lode' may be mineralised marble breccia.The marble breccia appears to be of diapric or sedimentary origin and there is evidence to support a sedimentary origin for some 'of the copper sulphides. No igneous rocks have been discovered within 20 miles of the mine and any hydrothermal activities were probably at comparatively low temperature. The possibility of extensive stratiform and disseminated copper sulphide mineralisation in the marble breccia and ore bed requires testing by further drilling and geophysicalsurveys.

Jan 1, 1963