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By M E. Taulis, S Hayton, D A. Manhire, J G. Pope

Successful development of coal seam gas (CSG) resources in low-rank coalfields such as the Powder River Basin has raised interest in CSG from low rank coal in New Zealand. Kenham Holdings Limited holds 12 Petroleum Exploration Permits (PEP) covering some of New ZealandÆs low-rank coal and lignite resources and has engaged CRL Energy Limited to assist in the systematic evaluation of the CSG potential of the permits. To date, exploration results from seven New Zealand coalfields reflect differences in coal type, rank, depositional environment and depth of burial between coalfields. Several of the explored coalfields are considered prospective for CSG. One of the most advanced Kenham exploration programmes is in the Hawkdun Coalfield, Central Otago.   The Hawkdun Coalfield contains a single, thick lignite seam with properties that are similar to the Powder River Basin. Preliminary results indicate the Hawkdun Coalfield is prospective for CSG with the potential to contain between 25 and 60 PJ of gas; enough to supply a 30MW power station for ten to 25 years. Further drilling is planned to investigate the economic viability of the Hawkdun Coalfield. The in situ permeability of the lignite, the amount and availability of free gas, gas saturation at depth and market opportunities will determine its economic viability. If initial pumping and production results in the planned exploration programme are promising, the Hawkdun Coalfield will be further developed with additional production drillholes to form a trial production pod.

Jan 1, 2004

Frother-Depressant Interactions in Two and Three Phase Systems

Sep 13, 2010

The application of biogeochemical methods in mineral exploration in semi-arid to arid environments in Western Australia has been investigated in an area near Norseman.The study involved a comparison of trace element characteristics of rock, soil and plants in the vicinity of the Pioneer BB prospect, where nickel-iron sulphide mineralization occurs in a "greenstone" sequence of ultrabasic, basic and sedimentary rocks.Analyses of unweathered and partly weathered rock from diamond drill cores show the ultrabasic rock to be highly variable with respect to Ni, Cu, Co, Zn and Mn.Samples of weathered bedrock and overlying soil were analysed for total trace element contents and for the trace elements associated with secondary iron and manganese oxides. Approximately 30 per cent of the total nickel content of the weathered basic rock is associated with secondary iron and manganese oxides, compared with approximately 15 per cent in the weathered ultrabasic rock.The soil has a sufficient residual content to provide a reliable indication of the chemistry of the underlying rock. Total trace element analyses of the -89 mesh fraction show strong anomalies for nickel and copper over the mineralized zone. Important amounts of nickel, cobalt and, to a lesser extent, copper are apparently associated with secondary iron and manganese oxides in the soil.Melaleuca sheathiana (tea tree) has been used to study the relationship between soil and plant chemistry. No strong relationship between plant and rock type was observed. Analyses were made of leaves, twigs, wood, bark and roots, and all plant organs were found to have anomalous nickel and copper contents near the mineralized zone. Leaves were found to give the best contrast in the anomalous area and to show fewer erratic values than other organs. It is concluded that the uptake of trace elements by tea tree is low in the semi-arid to arid environment of Western Australia, but that analyses of the plants do reflect the presence of mineralization.

Jan 1, 1973

Drilling at Ipswich during the last twelve years by the Queensland Department of Mines has proved large quantities of reserves which have assured the security of the field for many years to come. This is perhaps the greatest contribution to the development of the field since its discovery in 1827.The drilling campaign commenced in 1950 and by the end of 1961 comprised 242 holes totalling 180,220 ft.Intersections of formations and seams, accompanied by detailed surface mapping, led to more precise knowledge of the geology of the field than was previously possible, and clarified many problems of correlation. Productive formations are part of the Middle Triassic Ipswich Coal Measures, a 4,300 ft sequence of fresh-water sediments with some interbedded volcanics. They are overlain by the Upper Triassic Bundamba Group and the Lower Tertiary Booval Group.Reserves disclosed by drilling amount to 171,487,000 tons, comprising 109,407,000 tons "measured" and 62,080,000 tons "indicated". The security of these reserves encouraged many collieries to instal modern efficient mining machinery and washing plants.The climax of recent development of the resources of the field will be the commissioning in 1966 of a £33 million 360 MW power station in the Swanbank district which will consume 14 million tons of coal during its 30 year life and will have a peak demand of some 20,000 tons per week.Drilling is continuing and is expected to prove additional reserves which will justify further development of the field.INTRODUCTIONUntil 1949 there had been no concerted effort to test systematically the resources of the whole Ipswich field. Fifty two known holes totalling 30,500 ft had been drilled, eight of them by the Department of Mines, but because of poor core recovery and inadequate records most of them were of little use in a comprehensive assessment.Development of the field was being retarded by uncertainty regarding reserves and by the general state of the coal mining industry. Numbers of comparatively small independent companies and owner groups were operating coal...

Jan 1, 1963

The greater part of this paper comprises the material used in a lecture delivered to the South Queensland Branch of the Australasian Institute of Mining and Metallurgy in September, 1949. It contains little in the way of original matter, its main purpose being to call attention to the need for research into the properties of Queensland coals and to indicate some of the lines such investigations might profitably follow.Since the lecture was given the Powell Duffryn (1949) 1 report, which has made an excellent start along these lines, has been printed. This report is, however, only a beginning, though a big one, and there is ample room for many years of work along similar lines.The paper is based largely on the work of de Jersey (1946, 1949)2,3,4,5 and Jones and de Jersey (1947)6, but these workers in turn owe a debt to the work of many British and American investigators, too many to enumerate. The subject is a very large one-to deal with it fully would require not a paper but a book; all the author can hope to do is to discuss very briefly some of the main lines of investigation and indicate some of their applications.The reason for selecting Queensland coals in particular is the widespread ignorance of the extent of the coal resources of that State and the almost complete ignorance, to within the last year, of the modern industrial purposes to...

Jan 1, 1950

The New Technology of Enrichment of a Fine Low-Grade Tungsten from Complex Multi-Metallic Ore

Sep 13, 2010

By T F. McConachy, B I. A McInnes, R A. Binns

Within the last decade, major research discoveries have been made in the submarine realm of magmatic and hydrothermal activity of arc-backarc systems in the southwestern Pacific. These include identification of numerous particulate-poor, gas-rich (CO2-CH4) hydrothermal plumes emanating from arc front volcanoes, actively forming porphyry-copper-gold style mineralisation, and new backarc spreading systems erupting alkali basalt-trachyandesite magmas. Major goals of these studies have been identification of modern analogs to ancient volcanogenic massive sulfide ore bodies, and quantification of the volatile fluxes though supra-subduction zone systems.

Jan 1, 2002

By M Simpson

Greywackes of the greater Auckland Region (Brynderwyn Hills to Hamilton), when considered on a regional scale, have characteristic ranges of physical, mineralogical and other properties. Some properties (eg density, porosity, crushing resistance, clay index) generally cluster and correlate with the basement greywacke facies, regions and terranes recognised by geologists, and their diagenetic/metamorphic level. Other local factors, particularly variations in mineralogical composition, nature of matrix cement, grain size, and degree of weathering may produce aberrant properties. Some of these local variations, when extreme, have the potential to affect the aggregateÆs performance in roading or the concrete industries.   Smectite and the zeolite laumontite are the major deleterious minerals occurring in fresh greywacke rocks of the Auckland region, although weathered rocks may contain halloysite, an expanding member of the kaolin clay mineral group. These minerals, when found in abnormally high levels in greywackes cause expansion effects in the aggregate. Currently there are inconsistencies in the detailed correlation of shrinkage, clay index, clay mineral content and intrinsic expansion data that need further research to resolve them.  

Jan 1, 2007

Research and Tests on Improving the Technology of Enrichment of the Copper-Molybdenum Ore

Sep 13, 2010

By T Harding, T Riggs, D Taylor

High-grade hematite ores in the Hamersley Province of Western Australia are associated with hydrothermal magnetite-apatite and magnetite-hematite-carbonate-apatite proto ores below the modern weathering surface. In addition, hydrothermal alteration of country rocks, once believed to be absent, is now recognised widely in shales and dolerites up to several hundreds of metres away from the ores. Both observations appear to exclude a simple supergene model for ugrading the host iron formations to high-grade hematite ore. Similar hydrothermal proto ores and country rock alteration are now being recognised in other high-grade hematite deposits worldwide, or have been recognised in the past.

Jan 1, 2002

By C Noble, J Webster-Brown

A survey of selected West Coast Streams was undertaken in Summer 2001, Summer 2002 and Winter 2002 to establish the degree of arsenic (As) contamination in waters and sediments downstream of old coal and gold mine workings on the West Coast. Of the catchments studied, Soldiers/Ford Creek and Rapid Stream showed the most significant elevated As concentrations, predominantly in dissolved form, and evidence of AMD or ARD contamination (high sulfate concentrations and/or acidity). The rate and processes of removal of dissolved arsenic from the water column (attenuation) have been studied in these catchments. The Rapid Stream and Soldiers/Ford Creek catchments are directly affected by adit drainage from the Sullivan and Blackball coal mines respectively. Both catchments have high As concentrations in the sediments, with up to 770 mg/kg in Soldiers Creek and 490 mg/kg in Rapid Stream. Dissolved As concentrations are significantly elevated in the neutral pH waters of Soldiers Creek; typically as high as 100 - 200 ¦g/kg, up to 500 m downstream of the main adit discharge (800 ¦g/kg As). Adit inflows to Rapid Stream were acidic and contained 20 - 30 ¦g/kg dissolved As, with relatively high concentrations of arsenic in the stream water in winter (up to 18 ¦g/kg), but not in summer. Analysis of concentration trends and As:SO4 ratios downstream of these obvious As sources confirmed that dissolved As had been actively removed from the water column, but varied seasonally with greater removal evident in summer. Adsorption of arsenic onto iron oxide in the stream sediments is the most likely mechanism of removal. The Snowy River catchment, on the other hand, has relatively high As concentrations in both the sediments and the water column, but there was little evidence of a distinct AMD or ARD input from the Blackwater gold mining area. Preliminary investigation suggests that dilution rather than attenuation is responsible for decreasing As concentrations downstream.

Jan 1, 2003

The Effect of Ionic Strength of Plant Water on Valuable Mineral and Gangue Recovery in a Platinum Bearing Ore from the Merensky Reef

Sep 13, 2010

In spite of the many contributions that have been made to our knowledge of the creep properties of polycrystalline lead, the precise influence of various factors on these properties is not yet fully understood. Indeed, the position is such that several important points in connection with the creep of lead are a matter of controversy. This has been brought about largely by the fact that, in the case of lead, the changes that are produced in the creep behaviour by slight variations of such factors as the purity, grain sizeand previous treatment are out of all proportion to the magnitude of these variations.In order to study the fundamental properties of lead as related to creep, and so gain a more enlightened perspective with which to consider the creep of lead in general, the work that is described in a series of papers, of which the present paper is the third part, has been carried out. It deals with lead in the form of single crystals.It has been shown (1) - (3) that the grain boundaries as well as the actual grains play a part in the creep of polycrystalline lead. The present work, by eliminating grain boundaries, enables the. contribution of the grains themselves to the process of creep, in other words, crystalline creep, to be studied effectively.This object was, possibly, the major one in this work.

Jan 1, 1940

A calibration of the Frantz isodynamic magnetic separator relates the current in the electromagnet and the transverse slope of the chute to the specific susceptibility at which separation is being effected. In addition to providing a rapid measure of the specific susceptibility of minerals and composite grains, the calibration provides a guide to operation of the Frantz isodynamic separator for mineral separation, and to the nature of composite grains. The most sensitive magnetic separation is obtained by using the highest practicable current and transverse slope, and the lowest practicable longitudinal slope.INTRODUCTIONProbably all minerals have a magnetic susceptibility measurable by sensitive techniques. However, magnetic separation between minerals which have low but different specific susceptibilities, and which for many purposes are considered essentially non-magnetic, has only become practicable with the development of the Frantz isodynamic separator.The construction and principle of this highly sensitive separator has been described by S. G. Frantz as an appendix to a description by 'Gaudin and Spedden (1943) of its application to the separation of sulphides constituting mill products.Various publications (e.g. Hess, 1949, Hutton, 1952) refer to its use in separating the mineral constituents of rocks, ores, and unconsolidated sands.As used in this study the Frantz isodynamic separator consists of a vibrating chute mounted centrally between the pole pieces of an electromagnet (Fig. 1). This unit may be inclined in any direction by the universal mounting, and the electromagnet current is continuously adjustable from 0 to 1·5 amperes.

Jan 1, 1957

By G Liu

Seventy-nine gold deposits and prospects have been discovered in theJiamusi region of northeast China, and constitute one of the most important gold metallogenic belts in China. All these endogenic gold occurrences can be subdivided into three main deposit types: 1. porphyry related; 2. metamorphic-intrusive hosted, and 3. sediment-hosted deposit.   The first two types of gold deposit are spatially and temporally related to Mesozoic Yanshanian granitoid intrusions with hydrothermal activity channelled along crustal-scale fissures. The ultimate cause of the Yanshanian magmatism is considered to be the subduction of Pacific oceanic lithosphere beneath the Eurasian continent. In contrast, the chemical sediment-hosted deposit is typified by the Dongfengshan gold deposit, and genetically related to Proterozoic sedimentation and Mesozoic igneous activities.

Jan 1, 1995

Remote sensing, in general, is the recording of light and heat from a planet's surface within a certain range of the electromagnetic spectrum. For the Earth, systems capable of this recording are the MultiSpectral Scanner (MSS) and SLAR. The former is the recording system used in satellite and will be discussed in the next section. SLAR stands for Side Looking Airborne Radar. This device sends invisible radar waves which illuminate the Earth's surface. The reflected waves are subsequently recorded as images. The system can operate through darkness and dense cloud cover, and is particularly suited for the study of geological structures at both large and small scale (Wayland 1976). Remote sensing techniques are now widely being made use of in mineral exploration, especially for those last remote 'sanctuaries' where geological data are meagre or non-existent. For places like Borneo, West Irian, the Amazon Basin etc. remote sensing, in the form of both satellite imagery and SLAR, is of considerable help, in fact more often than not the only help, to delineate geological provinces, geotectonic domains and meaningful lineaments. In the case of New Zealand, well made geological maps at scale 1:250 000 by the Geological Survey are available to the public and these provide useful preliminary grounds for the selection of target areas. However, even in this case LANDSAT imagery can be of aid as will be shown later.

Jan 1, 1977

The Harmonious Design on the Beneficiability for the Pt-Pd Ores Containing High MgO Gangue in Yunnan

Sep 13, 2010

By Moorrees C, Everson P

A detailed examination of carbonic acid leaching of crude iron-containing magnesia derived from Savage River magnesite shows that the rate and extent of magnesium and iron dissolution are affected by the slake time, leaching temperature, carbon dioxide pressure, pulp density and rate of agitation. In order to produce high-purity magnesia from the leachate by precipitation and calcination, the optimum leaching conditions, which are those that yield maximum magnesium and minimum iron dissolution, have to be a compromise in terms of the above parameters. For example, iron dissolution can be limited by leaching at an elevated temperature (-45°C), but because the maximum concentration of magnesium biearbonate decreases rapidly with an increase in temperature, it is necessary to use a low pulp density (-2 per cent solids) in order to achieve an acceptable degree of magnesium dissolution.Evidence is obtained that iron dissolution involves the formation of a soluble ferric bicarbonate complex that decomposes at elevated temperatures. The extent of iron dissolution is much higher than might be expected and it is probably because the original magnesite contains siderite in solid solution with the magnesite; on calcination, the hematite whieh is formed is in a very finely divided condition and hence more reactive.

Jan 1, 1983

By G J. Lyman, F S. Bourgeois

As the prices of metals slide, financial control of mineral processing operations becomes more and more important. Control of a mineral processing operation implies measurement of grades, recoveries and losses, with every effort being made to recover more product from the same feed. Shareholders become more concerned with the transparency of the operations and the corporate governance.There is only one way to achieve this and this is by sampling and making good use of the results of that sampling. Sampling systems that provide only 'rough' figures are not good enough. Similarly, a competitive position in the marketplace demands close control of product quality. Maximisation of product output demands that the product just meet the specification so that product yield is maximised. Decisions based on precise sampling results carry less risk that those based on imprecise results.This paper reports some recent advances in sampling theory that permit full quantification of sampling distributions, not just the sampling variance as has been possible in the past. These advances can be used together with simulation methods to tie down sampling precisions and develop calculations that quantify decision making risk when using the sampling results. A number of examples illustrate the use of the new advances and a final example indicates the development of risk analysis curves in the coupling of sampling precision to sale of a commodity.CITATION:Lyman, G J and Bourgeois, F S, 2015. Sampling, corporate governance and risk analysis, in Proceedings MetPlant 2015, pp 27–34 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 7, 2015

Permitting, engineering and evaluation, detailed design and construction aspects of the Golden Cross goldmining project in New Zealand are briefly reviewed. The extremely lengthy and complicated governmental approval process together with the delaying tactics of opponents of the project are outlined and comment is made on aspects of the draft legislation proposed as part of the overhaul of New Zealand's resource management laws.

Jan 1, 1990