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In southeastern China, offshore Tertiarybasins are buried underneath the broad continental shelf areas from Taiwan to Hainan Island. These basins bear relatively similar characteristics of structure, stratigraphy and tectonics. Based on age and tectonic framework, these Tertiary basins are divided into two groups of Paleogene basin and Neogene basin (Fig.1 and 2). However, observations of extensional structures indicate that the Paleogene basins are rift basins; and the predominant structural features are NE-SW trending half grabens and fault blocks. In a regional scale, these half grabens and adjacent uplifts represent a horst-and-graben structural style. Neogene basins are downwarp basins lying on the tilting continental shelf. Late Tertiary sequences are relatively undeformed but locally with minor folding and thrusting during the Pliocene-Pleistocene.Seismic stratigraphy and well data indicate that the Early Tertiary strata are commonly tilted and disturbed as nonmarine to marginal marine facies deposited in the wedge-shaped half grabens; the Late Tertiary strata are generally parallel undisturbed marine facies accumulated in the enlarged downwarp basins overlying the infilled half grabens. In general, three major regional unconformities formed during the Late Cretaceous, the Late Eocene and the Middle Miocene. Widespread extrusive basaltic flows are commonly associated with these unconformities.

Jan 1, 1990

The Paracale gold region had been known for hundreds of years, but the first professional attempts to work the lode and alluvial deposits were made only in the 1890s by the London-based Philippines Mineral Syndicate. Complex ores, transportation problems, and the Philippine Insurrection halted operations. Ultimate success went to American firms, though Frank Karuth's Philippines Mineral Syndicate had pioneered the field.

Jan 1, 1987

By Wernick B. J

Recently, the Environmental Engineering Laboratory of the Chamber of Mines of South Africa Research Organization has made signifi- cant progress in the development of more accurate algorithms for assessing heat flow in gold mines. These algorithms have been incor- porated into an overall computer program, ENVIRON, which enables the complete thermo- dynamic analyses of mine ventilation and cool- ing systems to be carried out. Recently, efforts have concentrated on the development of an expert computer system which will guide engineers in the process of selecting the most appropriate environmental control strategy.

Jan 1, 1988

The short review of hydrogeologic conditions in the three Polish coal basins have been presented as the background for the prevention measures against water inrushes being underta- ken in coal mines. The Polish mine safety regulations concerning water inrush prevention have been discussed, namely: - classification of sources of the potential water inrushes, - levels of water inrush risk and conditions of mining operation in the mines facing particular risk levels, - determination of the -di.mens.ons.of protecting pillars to prevent water inrush to mines, protection of surface water reservoirs and their earth embankments in regions submitted to mining deformations. Three examples of coal mining being carried out under water bodies have been presented.

Jan 1, 1988

By the 1990's Australia could be the largest coal exporter in the world and one of the few industrialised countries potentially able to supply the shortfall in its domestic oil requirements by utilizing its oil shale and coal resources to manufacture synthetic oil. The major challenge to both industry and government in implementing the new role for Australia will be to ensure that their actions and policies enable the timely mobilization of resources needed to meet the potential demand for energy, both domestic and overseas. Australia's potential for coal production and exports and for the production of oil from shale and coal are discussed and the potential constraints to development Examined.

Jan 1, 1981

By Goode A

Since 1985 there has been a revival in the alluvial gold mining industry in North Queensland. However, not all mines which have been established have been successful, some times due to a misconception that alluvial mines are quick to establish and easy to operate. A check list of factors which need to be considered when assessing alluvial mining projects in North Queensland is presented and their relative importance is briefly discussed.

Jan 1, 1989

The exploration methods used by the British Coal Corporation in 1990 improve the geological reliability of underground coal production. Although some of the techniques in common use have been proved to be effective, their limitations are recognised and concentration has been on the increasing integration of direct and remote sensing techniques. Attention is focussed onto first seam workings in sections of at least 2 metres in the depth range of 400-1200 metres and covers both surface and underground exploration. The case studies of exploration techniques and their effect on mine design at several existing collieries are representative of a wide range of geological environments within the more productive British coalfields. Notwithstanding such improvements in exploration and geological reliability, further new exploration technology is currently being investigated or trialled by British Coal.

Jan 1, 1991

By S M. C Verryn

The amount of raw material used in the production of cement can be reduced by partially supplementing it by pozzolanic waste material without changing its properties negatively. This paper discusses results of an investigation using slag from the Pt industry, from the production of steel using Midrex processes as well as fly ashes from different coal power plants in South Africa. These are blended in a 20 per cent slag or fly ash to 80 per cent cement ratio. The properties of the mixtures depend on the phase composition, chemistry, grain size and the sources of the materials. The results are promising, but show variable behaviour depending on slag and cement composition. Compressive strength tests as well have heat flow curves showing the hydration behaviour, indicating that 20 per cent addition of slag or fly ash to ordinary Portland cement is viable. There is a large potential to use slag in cement mixtures and this study can be used to develop cements that will positively influence CO2 emissions and help to reduce large slag and fly ash stockpiles.

Jan 1, 2008

The paper presents an algorithm for calculating the natural air distribution in a ventilation network (sub-network) on the basis of following data: - for each network branch: labels of starting and ending nodes, label of the branch, resistance and natural depression; - for each fan: the characteristic in the form of a second order equation and initial flow.

Jan 1, 1977

Interest in mining narrow, vein-type ones has increased world-wide during the last few years despite the fact that prices of metals have not risen in proportion as production costs of mining, such as labour and energy.In many mines, where narrow ones are mined, the mining technique and equipment used have been poorly mechanized. The mining methods have been cut-and-fill or shrinkage stoping. Pneumatic jack-legs have been used for drilling and slushers have been used for loading.The methods that have been used can be called the "first-generation" methods.Work has been very hard for miners. It has been dangerous and exhausting.Production volumes of mines, and a s a result of that, also profits have been low.

Jan 1, 1990

By G K. Searle

In Australia, coal mines have generally not adopted filling to increase mining recovery. The aim of this project, entitled æImproved recovery in highwall mining using backfillÆ, was to examine the feasibility of using fill to improve recovery in highwall mining. Current fill practice was reviewed for metalliferous as well as coal mining, both here in Australia and overseas, for its applicability to highwall mining. Studies were then made at a conceptual level to determine whether fill could be economically used, to determine appropriate sources for fill and to trial key aspects of fill behaviour. A review of filling methods led to conceptual studies being undertaken on seven filling methods and these studies demonstrated that fill could be used to improve recovery. These studies were then further refined. Selected filling materials have been reviewed and laboratory tests have been made on these to assess their suitability.

Jan 1, 1998

By S Grano, J Ralston

Selective oxidation of minerals was used in this study to separate by flotation the copper sulphide minerals of chalcocite, covellite and chalcopyrite from the arsenic copper sulphide minerals of enargite and tennantite. It was found that a satisfactory separation of these minerals was only possible after selective oxidation of their surfaces in slightly acidic pH conditions, or after oxidation and selective dissolution of the surface oxidation products with a complexant in basic pH conditions.

Jan 1, 2000

By George CW

Western Mining Corporation (W.M.C.)operate a 30 000 tpa nickel refinery at Kwinana, W.A. using the Sherritt Gordon Process. Following ammonia/air leaching of sulphideminerals and subsequent copper removal, nickel metal is produced as powder by hydrogen red-uction of the ammonium sulphate-rich solution. Batchwise reduction in pressure autoclaves is preceded by an oxidation/hydrolysis step to ensure nickel powder quality.The reduction process is energy intensive, requiring high temperatures and pressures. Present energy requirement is 24 GJ per tonne of nickel reduced. Of this, 95% represents steam and hydrogen consumption and 5% electric power. The design and operation of the red-uction circuit is reviewed, outlining the main areas of steam and hydrogen usage.

Jan 1, 1985

The genesis of the Bulong Laterite Ni/Co deposit spans some 60 per cent of earth history: from development of the parent rocks in the Archaean to lateritic weathering in the Cainozoic. In a man's term, the discovery and evaluation history of the deposits has also been protracted and, at any given time, the perceived value of the deposits has depended upon the available technology and world markets.

Jan 1, 1996

By G D. Cooper

There are no manuals or handbooks for budding mill superintendents or process plant managers. Most who obtain this level of responsibility have gained their training from watching the good and bad of their predecessors and the successful ones have themselves graduated from the school of hard knocks. This paper attempts to provide some helpful guidelines and direction for those who aspire to better manage a mineral processing facility. The authors have 20 years combined experience in senior management roles at nine different mineral processing operations in Australia and overseas, covering gold, base metals and mineral sands. This summary of tips and pitfalls will hopefully benefit future leaders in mineral processing and metallurgy.

Jan 1, 2007

By Brown P. L

A study has been made of the geochemistry of the Ronneburg mine district as input to the overall management strategy for the rehabilitation of the mine site. The study drew on the geological data and information store developed over the 40 years of mineral exploration and mining at Ronneburg, and on chemical data from the literature which described the chemical processes of weathering, oxidation, dissolution and precipitation of minerals. The geochemical processes were divided into three groups based on their rate of reaction. Fast processes were assumed to proceed to equilibrium and were modelled using equilibrium chemistry equations; slow processes were assumed to be proceeding at a quasi-steady state rate and were modelled using chemical rate equations; very slow processes were assumed to have no role in describing the geochemistry for rehabilitation purposes.

Jan 1, 1995

A new plant for grinding limestone was built at the Risdon Works of the Electrolytic Zinc Company of Australasia Limited to meet increasing process demands expected to reach 150 tonne/day of ground limestone. Plant specifications included open- circuit wet grinding, a single ball mill, a feed sizing of minus 6 Tyler mesh, a product sizing of 100 per cent minus 200 and 95 per cent minus 325 Tyler mesh and for the plant to be unmanned during normal running. Main features of plant and equipment are described; grinding performances given, as well as operating experience since commission- ing of the plant in March, 1976.

Jan 1, 1977

By M Rispin, R Karlson

Chemical admixtures are not commonly included in the variety of backfill mixes used in the mining industry. This may be attributed to several reasons including, but not limited to: the perceived high added cost, the lack of awareness about their proper use, and the lack of knowledge about their features and benefits. In the construction industry today, however, chemical admixtures are used in the majority of the concrete produced, enabling concrete to become a more cost-effective building material. They also enable construction crews to meet demands for year-round construction, quicker completion of construction projects, and improved concrete properties. The high demand for chemical admixtures in the construction industry has led to numerous innovations in admixture technology in recent years. Some of these chemical admixtures have been found to enhance the production, transport, placement, and in situ properties of backfill mixes. Others have been found to reduce the cost of such mixes while maintaining, and in some cases improving, their physical properties. In this paper, a few of such innovative admixture technologies are discussed. The benefits, imparted by these technologies to backfill mixes as well as performance data on their use in several backfill applications at various mines, are presented.

Jan 1, 1998

The Australian industrial relations system is in a state of constant change. We are undergoing a transformation from a compulsory arbitration and an award based system to one which is fundamentally rooted in the concepts of enterprise bargaining. This is true both at the State and Federal level. The structural changes which facilitate the movement away from the predominance of Awards to enterprise agreements has been fostered by both sides of the political spectrum and is a cornerstone of their respective industrial relations platforms.In determining what form or combination of forms of industrial instrument(s) should apply to the individual enterprise, employers must have regard to the viability and sustainability of each form in the changing industrial climate. In particular employers should have regard to the needs and agendas of their employees and unions which may purport to represent Them.

Jan 1, 1998

Following a period or small-scale activity a joint venture was formed between Ceramco Limited of New Zealand and Georgia Kaolin Company of USA. The initial concept was to process clays for the paper industry but it soon, became apparent that insufficient markets were attainable for the grades of china clay that could be produced for an economic unit. Ceramco Limited acquired the Georgia Kaolin interest in 1975 and proceeded to search for a market, of markets, that would: 1. utilise the unique properties of the product, and 2. enable a viable operation to be created. This paper describes the mineral deposits, the process, the properties of the product, and the marketing methods of New Zealand China Clays.

Jan 1, 1984