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The Barra Mine was the most significant mine of Australia's earliest mining era, which took place in South Australia between 1841 and 1851, the decade prior to discovery of gold in eastern Australia. Between 1845 and 1860, Barra was the largest metalliferous mine in Australia and employed up to 1000 men and boys, most of them Cornish.""Today the site is also important in a physical and archaeological sense as it contains extensive remains of mining and processing operations of the period 1850 - 70. Most significant are three cnginchouses which housed Cornish beam engines.

Jan 1, 1993

By J Harmse

This paper deals with the modernisation of the brakes on an electrically coupled Blair multi-rope hoist and covers the removal of the old calliper brakes and hydraulic control system, and its replacement with brake discs, disc braking units and hydraulic control systems. The paper covers the braking requirements of the hoist, which is made up of two electrically coupled single-drum hoists, together with the theory behind the choice of brakes and control systems supplied. The paper also covers the project logistics that were required in order to install and commission the new brakes and control systems with the minimum disruption to production on the only rock hoist on a major production shaft. Items covered include the modifications to civil works, pre-installation of bearing lubrication systems, brake discs and hydraulics and the interfacing of the new hydraulic control system to the existing electric control system. It had to be designed to be compatible to a new electric drive and control system due for installation at the end of 2005.

Jan 1, 2005

Knowledge of coalfield geology has evolved rapidly over the past few years. Recent advances ranging between exploration, mining geology and seam variation studies have enabled application of geological techniques commensurate with technological changes in the coal industry.

Jan 1, 1969

At Hilton Mine, 18 kilometres north of Mount Isa, the silver-lead-zinc sulphide bodies have undergone strong deformation in the form of folding and later faulting and brecciation in the hangingwall region of the mine. Variation in grades and widths over compara- tively short distances causes problems regarding accurate sampling of orebody exposures in underground development, and in defining confidence limits for the extrapolation of ore intersections in ore reserve calculations. The paper gives a preliminary insight into the problem of obtaining representative samples for exposed orebodies and discusses the sampling techniques employed. Results gained from these sampling methods could not be verified due to lack of individual bulk samples for comparison but strong evidence for precision was provided. INTRODUCTION In a developing mine like Hilton, accurate grade information is of extreme importance. Original grade information for a potentially viable ore deposit is gained from surface drilling, and initial ore estimates are calculated from the resultant ore widths and grades. After underground development has proceeded, the opportunity arises for detailed examination of orebody exposures, and the resultant assay grades and widths from sampling of these exposures may, in the long term,

Jan 1, 1976

By P Ritchie, E H. Briese, N A. Currey

Kidston Gold Mines, located in semi-arid North Queensland, Australia is currently in its closure phase. Highly innovative and comprehensive rehabilitation strategies were employed at the site, including the direct revegetation of the surface of the tailings storage; the construction of a tailings sediment entrapment pond; the construction of a spillway to drain large rainfall events from the surface of the tailings; the construction of store/release covers over the tops of the waste rock dumps; the sheeting with oxide waste rock of the waste rock dump slopes; the partial back-filling of the initial Wises Hill Pit with waste rock and thickened tailings produced from the subsequent Eldridge Pit; the partial flooding of Eldridge Pit following the end of mining; and the construction of wetland systems to treat contaminated tailings and waste rock dump seepage. These closure strategies involved the careful consideration of water management. Specific water management issues included understanding the water balance of the tailings dam; the operation of the tailings dam sediment entrapment pond and spillway; understanding the water balance of the store/release waste rock dump covers; the importance and sustainability of vegetation on the tailings, store/release waste rock dump covers, and on the sheeted waste rock dump slopes; the level and quality of water in the partially flooded Eldridge Pit; and the treatment of contaminated seepage in the constructed wetlands. The seasonal and highly variable rainfall experienced in this semi-arid climate posed a number of challenges for the management of water on the site post-closure. The paper details these challenges and highlights how they were resolved over the period leading up to and following the end of mining.

Jan 1, 2003

By N K. DavT, A Coggan

The performance of in situ, shallow water covers in controlling acid generation was evaluated at four recently decommissioned pyritic uranium tailings sites at Elliot Lake, Ontario, Canada. The tailings are acid generating, having a pyrite content of approximately five to ten per cent and a very low to non-existent alkaline buffering capacity. Adverse market conditions led to the closure of all operating uranium mines in the early- to mid-1990s, followed by rehabilitation and decommissioning of mine and waste management facilities. In order to control acidic drainage, all new and active tailings areas at Denison, Quirke, Panel, Spanish-American and Stanleigh mine sites were re-engineered to provide in situ submersion of these tailings under shallow water covers. The tailings impoundment dams were upgraded and reinforced or in some cases reconstructed, to minimise seepages and provide a minimum 1 m depth of water cover. With the exception of Stanleigh mine, which was closed in 1996 and rehabilitated during the late-1990s, the water covered Tailings Management Areas (TMAs) at other sites have been in operation for a period of six to nine years. The surface water quality at these sites is maintained at near neutral pH conditions by periodic addition of lime slurry to the established water covers. Additional treatment of effluent is provided as required to meet the discharge water quality standards. The performance of the established water covers at the sites was evaluated by analysing the annual equivalent limestone consumption data. The results were compared with the performance of an older, decommissioned Nordic TMA, which was rehabilitated using revegetation techniques. The water covers at these sites are performing as designed and acid generation has been reduced to low levels. Based on the total amount of yearly equivalent limestone required to maintain water quality in the water cover and at the effluent treatment plant, it is concluded that acid generation rate at the Denison TMA has reduced to less than 0.15 per cent of its pre-water cover conditions during normal operation and rehabilitation periods. In comparison to the revegetated Nordic TMA, the acid generation rates at Denison and Panel TMAs have decreased to less than 1.6 per cent of that at the Nordic TMA. The acid generation rate at the Quirke TMA was comparable or only slightly lower than that at the Nordic TMA because of its unique terraced cell configuration, having tailings in five hydraulically interconnected cells at different elevations. Historic acidity and oxidation reaction products, accumulated during normal operating and pre-water cover periods, are flushing from upstream locations to downstream cells, thus requiring much higher equivalent limestone additions for acid neutralisation and effluent treatment.

Jan 1, 2003

WaihiÆs Cornish Pumphouse is located on the edge of town in a dynamic and changeable area where history affects the future. As in any successful project, ingenuity and team work have been significant factors in the planning and implementation of the buildingÆs relocation.   Work around the Pumphouse site commenced circa 1900 with preparation to sink the No 5 shaft. Construction of the pumphouse and the steam driven C pump was completed by 1904 with hints of what was to come evident in 1905 as the No5 Shaft collar had sunk 350mm in four years. By 1907 surface cracking developed over the Milking Cow cave area and in 1913 200 mm was cut off the main pumping rod as the ground was sinking at a rate of 25 mm per year.   In 1913 ground around No 6 shaft had subsided 600 mm.It was also the end of an era as steam gave way to hydroelectricity and electric pumps replaced the C Pump. C Pump was maintained as a backup from 1913 to 1929 and then finally scrapped. 25 years of underground caving operations removed approximately 400 000 cubic metres of ore leaving a 7 ha collapse crater that eventually became known as the mine lake.   On the edge of town a tension zone over the Royal Lode began to develop 50 m diameter chimney collapses as large scale blocks relaxed into unfilled stopes in the old Martha underground mine. After the 1999 collapse part of the main street was closed and after the 2001 collapse Hazard Zones were declared, more streets closed and areas evacuated and retired from residential use.   By 1984 the Pumphouse has approximately one degree of tilt and in 2002 tilt on the Pumphouse accelerated briefly and then settled down. Tilt accelerated again late in 2004 and a scoping study was initiated to define protection options for the pumphouse. The Martha Mining Licence requires Newmont to 'Take whatever precautions are necessary to protect the old Cornish Pumphouse adjacent to No5 shaft' and viable solutions needed to found.   Any work on the Pumphouse comes standard with a wide range of stakeholders, governing agencies and legal framework to consider. Land Information New Zealand (LINZ) is owner and administrator of the pumphouse.

Jan 1, 2006

By D Bradshaw, E Forbes, M Edraki, M Tayebi-Khorami, E Manlapig

There is an increasing trend in the extraction and development of copper resources from complex deposits. These deposits pose mineral processing challenges, as they often contain low grade disseminated copper ore with high levels of impurities particularly arsenic. Although arsenic is a naturally occurring element, the concentrations of arsenic can be magnified by mining and mineral processing activities. Therefore, while arsenic has no significant market value, its presence in the ore deposit will have production, environmental and human health implications. The mining industry’s approach to life-of-mine planning has improved significantly in recent decades and managing arsenic is not an exception.CITATION:Tayebi-Khorami, M, Edraki, M, Manlapig, E, Forbes, E and Bradshaw, D, 2018. Arsenic pathways in copper mining – sustainability issues and potential solutions, in Proceedings Life-of-Mine 2018, pp 60–63 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 25, 2018

By D Judkins N OÆLoughlin

"Basin Minerals Limited commenced exploring for conventional strandline hosted mineral sands (rutile, ilmenite and zircon) deposits in the Murray Basin in April 1997. This has resulted in the discovery of a major mineral sands field in the Douglas Project area, located southwest of Horsham in the Wimmera Region of Western Victoria. After the successful completion of a pre-feasibility study on these deposits in September 2000, the Douglas Project has advanced to bankable final feasibility study. This study should be completed by mid-2002 to allow a decision to commence production in 2003 at an expected rate of in excess of 500 000 tonnes of combined mineral sands products per annum. The field comprises several mineralised strandlines. The main ones of economic interest are from west to east, the four strandlines, Acapulco, Bondi, Bondi East and Echo. These strandlines at August, 2000 contain total Inferred Resources of 443 million tonnes at 4.7 per cent HM at a one per cent HM cut-off; ie 20.8 million tonnes of heavy mineral concentrate which in turn contains 11.3 million tonnes of ilmenite and leucoxene, 1.3 million tonnes of rutile and 1.6 million tonnes of zircon. The heavy mineral concentrate is coarse-grained with mean diameter grain size of the strandline deposits ranging from 130 to 160 microns in size. Major controls on the formation of mineral sands deposits in the Murray Basin are discussed with reference to the main mineral sand bearing, strand plain domains; the Central Strand Plain, the New South Wales Strand Plain and the West Wimmera Strand Plain. The Douglas Project deposits on the West Wimmera Strand Plain domain are characterised by wide zones of mineralisation with high-grade cores (>10 per cent HM), low stripping ratios, and a valuable economic heavy mineral suite comprising 60 to 80 per cent of heavy mineral concentrate. Constituent mineralogy of the heavy mineral concentrate of the overall deposits is; ilmenite (40 to 58 per cent), leucoxene (five to seven per cent), rutile (four to ten per cent) and zircon (four to 14 per cent). The Douglas Project Area appears to be endowed with significantly enhanced levels of heavy minerals compared to other areas of the Murray Basin due to its unique palaeo-geographical position. Long shore drift to the south of the basin has caused large quantities of heavy mineral to be trapped against the palaeo-cliffs and headlands of a rugged palaeo-coastline which includes in a major embayment, the Grampian Mountains, the Black Range and the Glenelg Complex. To the east, major faulting and uplift has brought the fine-grained WIM offshore deposits close to the surface and has resulted in erosional stripping of mineralised strandline deposits. This mineralisation has been recycled and reconcentrated within the younger strandlines to the west within the adjacent Douglas Project Area. These strandlines are thought to be younger than other mineralised strandlines discovered to-date in the Murray Basin. The Project Area strandlines are described; ie their morphology, geology and patterns of mineral distribution. The mineralogy of each of the strandlines is distinctive and variations are noted along strike and section."

Jan 1, 2001

By D S. Perera, P Wal, D C. Southam, J L. Lowe

The Cooperative Research Centre for Sustainable Resource Processing (CSRP) is undertaking a large research project involving partners from industry, universities and government, which aims to develop the necessary chemical and structural understanding of geopolymer materials made from waste products for them to be used to capture a significant market share of the concrete business for a given industrial region. We are investigating the suitability of a range of soluble silica-bearing waste streams for use as geopolymer concrete feedstocks. In order to utilise a variety of waste streams, either singly or blended, an understanding of the role of secondary metal ions (Fe, Ca, Mg, Ti, etc) in the geopolymerisation process is essential. A range of experimental and analytical techniques is therefore being used to better understand the structure-chemistry-property relationships of geopolymers. Currently, we are investigating geopolymers made from a variety of waste streams (fly ash, kaolinite, red mud, etc) available in the Kwinana Industrial Region, Western Australia. This paper will detail how the basic scientific research underpinning the project is vital if waste streams of varying composition are to be successfully used in a commercial concrete product and the regional synergies required to develop geopolymers from waste streams.

Jan 1, 2006

By M Byrne, P Newman, M Lindqvist

SomincorÆs Neves Corvo Mine, one of the largest copper producers in Europe, is currently constructing a paste backfill plant in order to replace cemented rockfill in its bench and fill stopes and possibly replace hydraulic sandfill in the drift and fill stopes. A 250 m flow loop was constructed at the mine and the flow properties of various paste blends were investigated. Cycloned tailings and total tailings were both pumped successfully as pastes and were also combined with waste rock for additional testing. The pressure losses in 102 mm and 154 mm diameter pipeline were recorded at flowrates up to 60 m3/hr and are presented at slumps from 120 mm to 250 mm. The data showed the sensitivity of paste mixtures to slight changes in consistency, confirming the need for accurate control during paste production and distribution. The flow results clearly showed the different paste behaviour between cycloned and total tailings pastes and the change in properties at low and high slumps. In addition to pressure loss data, strength testing was done on 38 mm and 82 mm diameter samples. Further strength testing is ongoing at the mine using fly ash as a supplement to cement, reducing the overall binder cost. Preliminary engineering for the underground distribution system is briefly discussed, with reference to the siting of the plant. The Neves Corvo Mine is particularly shallow and alternative methods to pumping were sought in order to ensure sufficient hydraulic head for underground distribution. The comparison of options had to take into account the capital and operating costs, the operation of the plant and the impact on the future expansion of paste fill utilisation at Neves Corvo.

Jan 1, 1998

By S Wainio, P J. Beckett, T Miller

Lichens are a symbiosis of fungi and algae. Air borne elements and gases are absorbed very efficiently over the entire surface of the lichen, because they have no protective structures such as a waxy cuticle or stomata. A survey in 1977 (one year before the Sudbury Regreening program began), indicated that several Cladonia spp had invaded the soil in Sudbury’s open birch woodlands. Pollution sensitive species such as Cladonia rangiferina and C. mitis occurred 20–25 km from the smelters. It was anticipated that the improvements in air quality and reclamation efforts would allow a natural invasion of pollution sensitive species into what once was a lichen desert that surrounded the smelters. The purpose of this project was to study the invasion of terricolous (soil-inhabiting) communities of lichens and mosses on reclaimed land in the Sudbury region 45 years after commencement of the Sudbury Regreening Program.

Aug 2, 2023

Downhole survey uncertainties observed at various De Beers operations prompted an investigation into their possible effect on deposit shape and volume. An accurately surveyed artificial æboreholeÆ was constructed and different downhole survey instruments tested. In this way an empirically determined error range of 0.1 per cent to ten per cent was derived for downhole survey data. These survey errors were applied to an orebody model at an existing mine. Visualising the sphere of uncertainty associated with a borehole trace using a general mining package (GMP) gives an indication of possible volume variance. The resulting orebody maximum and minimum volume scenarios for three different depths (200 m, 500 m and 800 m) are presented. For certain instruments and borehole angles, the 3D positional error can be as high as 100 m at 1000 m down the hole. At depths below 200 m the resulting volume deviations can become significant for borehole survey errors exceeding 0.35 per cent. At 800 m depth the volume difference can approach 25 per cent. These figures assume that the error is compounded. The impact of these downhole survey errors is greatest for pipe-like orebodies such as porphyries and kimberlite pipes. Subhorizontal sill-like orebodies (and coal seams) will not be significantly affected by these errors. The impact of this type of survey error needs to be stated (and quantified) and is significant in JORC classification.

Jan 1, 2009

By N Madani, Y Abildin, E Topal

Mine planning is a crucial part of all mining industry projects, and nowadays, geometallurgical mapping through advanced computer technologies provides an opportunity to involve metallurgical responses of a deposit into 3D block model in order to optimise mine planning activities, especially for production forecasting. Including these metallurgical parameters apart from traditional geology and grade-based attributes into resource modelling leads to an extensive approximation for the economic maximisation of mine production due to better forecasting, planning and increasing certainty and the reliability of the resource model (Macfarlane and Williams, 2014). Commonly, geostatistical techniques and algorithms are used to produce models with the high resolution (Brissette et al. 2014; Deutsch et al. 2014; Tolosana-Delgado et al. 2015). The accuracy of the modelling procedure deeply depends on a reliable block model, produced by spatial analysis of corresponding variables that define the geological, metallurgical, mineralogical and chemical behaviour of the deposit. However, there are special cases, where the application of enhanced geostatistical methods is required, to solve the occurred difficulties between variables with multivariate complexities. For example, in oxide copper deposits, the soluble copper grade is a percentage of total copper grade and recoverable by heap leaching processes (Emery, 2012; Hosseini and Asghari, 2015). Hence, the joint spatial modelling of these variables has two difficulties.CITATION:Abildin, Y, Madani, N and Topal, E, 2018. Forecast the mineral processing destinations based on spatial interpolation of geometallurgical variables, in Proceedings Complex Orebodies Conference 2018, pp 2–5 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 21, 2018

By C E. Loayza, R M. Pinto, J G. G=mez

The Yanacocha District is located 20 km north of the city of Cajamarca, in the Northern Andean Orogenic belt of northern Peru.Gold production may have occurred as early as Incan times (Paverd, 2000), but modern exploration that began in the 1960s targeted only copper and silver. Newmont Mining Corporation, BRGM and Compa±fa de Minas Buenaventura began exploring for gold in 1983, with Newmont as operator.Initial drilling took place in 1985. By 1992 a reserve of 1.28 million ounces was reported (Teal et al, 2002).Production began at the Carachugo deposit in 1993.Current reserves are 31.7 million ounces at $US 325 per ounce at a grade of 1.03 ppm (Newmont Annual Report, 2003).The operating company, Mineral Yanacocha SRL (Newmont 51 per cent, Buenaventura 44 per cent and International Finance Corporation five per cent) produced 2.85 million ounces in 2003, making Yanacocha one of the largest gold mining operations in the world. The district is made up of a series of epithermal, high sulfidation style gold deposits and one gold-rich gravel deposit (La Quinua), aligned in a NE trend.La Quinua is not discussed in detail in this paper. The bedrock deposits are hosted in a Miocene volcanic package, the Yanacocha Volcanic Complex that also trends NE.Re gional NW striking Andean faults intersect the NE striking Trans-Andean Chicama-Yanacocha structural corridor (Turner, 1997), localising the district mineralisation. These two structural orientations dominate the district, controlling breccia and intrusion locations, and gold mineralisation. Discontinuous EW oriented fracture zones are interpreted as extensional and locally are important in controlling gold mineralisation.

Jan 1, 2004

By G R. Hancock, W D. D P Welivitiya

is placed in a waste rock dump, which is usually later reshaped to be erosionally stable, initiate and sustain vegetation and ultimately integrate with the surrounding undisturbed landscape. However, it is unclear how this exhumed material will weather and evolve for most sites. Also, there is a lack of data on the weathering of post-mining materials. If weathering is better understood, then there is the potential to improve rehabilitation outcomes. To improve predictions of the evolution of soil properties and weathering-limited erosion, estimating the rate at which fine, transportable material is produced from the weathering of larger, non-transportable particles and the resultant fragment size distribution and how that distribution evolves over time is necessary. This study examines the weathering process for four different coalmine waste rock materials for a Bowen Basin, Queensland site. Materials obtained from various areas of the coalmine were subjected to cyclic wetting and drying and heating and cooling. Particle size distribution and other material properties were explored after each experimental cycle to ascertain how the material changes during the experimental cycles. The particle size distribution data of wet and dry cycles were used as input data in a numerical weathering model to explore the dynamics of the weathering process for each material sample. A Monte Carlo framework was employed to assess the geometry of the weathering products, weathering rate and the number of daughter particles produced within a weathering cycle. Then the SSSPAM Landscape Evolution Model was used to evaluate the influence of weathering on erosion and landscape evolution of a post mining landform. SSSPAM simulations with: (i) active weathering and (ii) without weathering were run for each material. The erosion rate and the overall landform structure were then compared between weathering and non-weathering simulations.

Aug 2, 2023

By G R. Hancock, M J. Saynor, J B. C Lowry, T J. Coulthard

Landform evolution models (LEMs) can assess the effectiveness of landform designs applied to a rehabilitated landform by predicting where erosion may occur. Here, we compare erosion predictions produced by the CAESAR-Lisflood LEM with field observations from the rehabilitated Pit 1 landform of the Ranger uranium mine, based in the Northern Territory, Australia (Figure 1). The ability to predict long-term erosion at a catchment scale is important, as the final rehabilitated Ranger landform is required to physically isolate buried tailings material for at least 10 000 years. CAESAR-Lisflood has been extensively tested and calibrated using data collected from erosion plots (0.09 ha) on the Ranger trial landform (TLF) for multiple years (Lowry et al, 2020; Saynor, Lowry and Boyden, 2019). However, until recently, it was impossible to compare model predictions with field observations for areas larger than the TLF erosion plots. We can now compare model predictions of Life of Mine Conference 2023 | Brisbane, Australia | 2–4 August 2023 116 gully development with field observations from the newly rehabilitated, 40 ha surface of Pit 1 over two contiguous one-year periods: 2020–2021 and 2021–2022. The aim of this study was to assess whether the CAESAR-Lisflood model can successfully predict gully erosion at a larger spatial scale.

Aug 2, 2023

By M B. Lovitt

At present there exist few engineering calculations and principles to determine exclusion zones for personnel in the vicinity of underground explosive storage areas. This paper is written to encourage discussion and proposes a method to determine the impact of a blast wave through scientific principles. Then, criteria to determine an ‘exclusion zone’ need to be identified.There has been much work on identifying the pressure rise and the energy of explosive detonations underground but little to develop standards in criteria that can be used to identify exclusion zones for useful design of underground infrastructure. The author presents the newest ways of calculating the pressure rise and energy (impulse) of detonations and puts forward some criteria to be used in the identification of personnel exclusion zones to spark peer review and discussion of these criteria towards developing standards for engineering design.Smith and Sapko (2005) used Sach’s scaling laws to develop a relationship for both pressure rise and impulse, which incorporated factors for intersections. Intersections will have a large bearing on the peak pressure and the energy of the blast wave and needs to be incorporated. Silvestrini, Genova and Leon Trujillo (2009) developed the scaling laws with an energy concentration factor to predict blast propagation in partially confined geometries and together the author has proposed equations for determining the peak side pressure and the impulse in a tunnel. Given the weight and type of the explosive, the average cross-section of the tunnel complex and the number and type of intersections encountered, the pressure and impulse can be calculated.The military has carried out many investigations as to the influence of blast pressure and impulse on the human body. Lung damage, ear damage and velocity knock down are three of the criteria standards that are presented as possible methods of determining exclusion zones around an underground explosives magazine. The author suggests that the velocity curves presented by Bowen, Fletcher and Richmond (1968) could be an acceptable method of determining an exclusion zone as it incorporates the side pressure and the energy of a blast wave to determine the ability of the wave to knock down personnel.CITATION:Lovitt, M B, 2014. Exclusion zone calculation for underground explosives storage, in Proceedings 12th AusIMM Underground Operators’ Conference 2014 , pp 319–326 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Mar 24, 2014

Universal Resources Ltd has acquired a large portfolio of high quality exploration projects in two of Australia's most prospective regions for base and precious metal exploration: the Mt Isa Inlier (the Mt Isa-Cloncurry area) of North West Queensland, and the southern Lachlan Fold Belt in New South Wales. Drilling techniques commonly employed by the company for mineral exploration include diamond core drilling, air core drilling, reverse circulation (RC) drilling, and rotary air blast (RAB) drilling. Using examples from these two regions, each drilling technique is briefly described and compared, with particular reference to the specific advantages and disadvantages of each method for: sampling size, sample representivity, recovery, integrity and potential contamination. The applicability and implications of the different drilling techniques described for subsequent mineralogical and metallurgical evaluation work are discussed.

Mar 1, 2010

By Davies H, Pigram C, Sunata W, Falvey D, Loxton C, Giddings J, Rogerson R

PALAEOMAGNETIC CONSTRAINTS ON TERRANE TECTONICS IN NEW GUINEA Chris Klootwijkl), John Giddingsl), Wahyu Sunata2), Chris Pigraml), Charles Loxton3), Hugh Daviesl), Rick Rogerson3) and David Falveyl) 1) Bureau of Mineral Resources, Canberra, Australia 2) Geological Research and Development Centre, Bandung, Indonesia 3) Geological Survey of Papua New Guinea, Port Moresby, Papua New Guinea

Jan 1, 1987