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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

By Pollard D. M

Chalcopyrite samples from two different localities were leached in oxygenated mixed chloride-sulphate lixivants at elevated temperatures and atmospheric pressure. The oxidation of chalcopyrite was found to follow predominantly linear kinetics. The slope of the major region was dependent on stirring rate, oxygen flowrate and chloride concentration while only slightly dependent on the surface area of the sample leached. This region was found to predominate only at low temperatures. The oxidised chalcopyrite releases cuprous and ferric ions into solutions. Chloride ions complex these dissolved ions to effectively move the equilibrium of the leaching reaction to the right. When the level of chloride in solution was below 6 g/l, the unstable cuprous ions were found to reprecipitate with sulphur as covellite. When no chloride was present and the lixivant was a solution of sulphuric acid then ferric sulphates precipitated. The overall leaching reaction occurring in the leaching system is: CuFeS2 + 5H+ + 1.25 02 = Cu 2+ + Fe 3+ + 2S¦ + 2.5H20

Jan 1, 1987

By Maxwell HW

Pacific Coal Pty Limited (a wholly owned subsidiary of CRA Limited) managed the interests of six members of a joint venture formed to mine and export eight million tonnes of export quality steaming coal from a mine developed at Blair Athol in the Bowen Basin of the Central Queensland coal fields. The mine is now operated by Blair Athol Coal Pty Ltd. Crooks Michell Peacock Stewart Pty Limited (CMPS) was awarded a project management and engineering contract for the total mine portion. Following a feasibility study, CMPS carried out an Optimisation Study which produced changes to the design of the project, thus resulting in the project budget being reduced by some A$13 million. In spite of a number of late additions to the scope of work, the project was completed at a final cost of A$148 million, many millions below the reduced project budget. The project was also completed several months ahead of schedule. Total services were provided to take the project from feasibility stage through to the establishment of an operational facility and included project management, planning and control, accounting and financial control, as well as the organisation of engineering, procurement, construction, industrial plant commissioning, and technical training matters.

Jan 1, 1986

By M Wortley, A Cantarutti, G J. Clarke, C

As part of a broad program to optimise the performance of their grinding circuit, BHP Billiton Cannington have installed an OCS¬ Expert system together with three VisioRockÖ online particle size analysis cameras. The main purpose of the system is to stabilise grind size and feed to the flotation circuit. This particular application of OCS¬ is the first installation to incorporate Metso Minerals Process Technology-Asia PacificÆs (MMPT-AP) Dynamic SAG/AG Mill Model, which is able to predict numerous mill parameters that were previously unable to be measured with the existing plant instrumentation. Integrated into the logic of the control algorithm are online vision based, particle size measurements of the AG mill feed and recycle crusher product. This paper will describe the history of the project from initiation to date, the model and OCS¬ logic configuration, and demonstrate the significant benefits realised at Cannington mine.

Jan 1, 2007

By P Benjamin, H Bohannan, C Farr

Geoffrey Blainey's historical account of the mining activity on the west coast of Tasmania, æThe Peaks of LyellÆ documents the changes over 130 years of activity in the region. Commissioned by the Mount Lyell Mining and Railway Company, emphasis is placed upon the development of the Mount Lyell Mine in Queenstown. Chapter 19 æWidening HorizonsÆ details the review the Mount Lyell Company undertook in 1904/05 to ensure the future of the operation, following the pessimistic outlook regarding diminishing reserves and poor grade ore. The analogies documented between the Mount Lyell Company at that time, and Gold Mines of Australia 90 years on are remarkable, with both companies demonstrating a commitment to the Mount Lyell area through active exploration, the proactive search for alternative technology and the recognition of the valuable human resource. As Blainey writes (Blainey, 1993), æwith its expanding chemical works, its huge Tasmanian mines, its railways and smelter, its coke works and its mine crusade, Mount Lyell was probably one of the nation's five great industrial companies in 1906 or 1907. This brief phase of industrial and mining expansion had its seed in the threat of extinction . . .Æ After a number of reprieves, the Mount Lyell mine did stop production in 1994, but that only provided an impetus for a review and rebirth.

Jan 1, 1998

WMC Resources Ltd has been involved the development and trialling of an automated load haul dump vehicle system since 1997. This paper describes the introduction of the system into the Olympic Dam Operation and its performance compared with existing manual loaders. In certain situations the autotram loader will outperform the manual operation, particularly on the longer distances. There were no personnel injuries associated with the operation of the system during the testing period.

Jan 1, 2005

By C Standing, R Lacourt Rodrigues, C Q

The value of iron ore depends on the grade of the contaminants. Scheduled iron, and the associated contaminants, provides mine planners with a measure of stockpile feed and blending requirements. Blending at the stockpiles is one approach to optimising iron grade, while minimising the variability of contaminant grades. These schedules are typically based on resource models incorporating geology and iron and contaminant grades. Resource models reflect best estimates of trends for each of the elements rather than the potential variability, which is critical for accurate short-term blending. Conditional simulation provides a tool to describe the likely variability of each element. Only recently has conditional simulation technology allowed the inherent correlation between elements to be incorporated into the process. This paper presents the stepwise co-simulation process used to simulate and describe multi-element variability for effective mine planning. A case study using the multi-element conditional simulation and the subsequent uncertainty in the schedule and stockpile planning is presented. This process supports proactive mine planning to minimise unexpected fluctuations in the final product.

Jan 1, 2005

By Morris A. E

The thermodynamically-based pyrometallurgical simulation software STEPSOL (Version 3.0) provides for the modelling of activities using the Interaction Parameter Model, the Regular Solution Model, the Sub-Regular Three Suffix Margules Model, the Sub-Regular Four Suffix Margules Model and various simpler polynomial models. These are briefly reviewed, along with the major sources of data available in the literature, and the implementation of the models in the program.

Jan 1, 1992

An efficient energy management programme can often significantly reduce a company's energy costs. The programme consists of a series of steps, namely a statement of support from senior management, assigning the management team, the energy audit, defining the goals and comwnicating with and training employees. The energy audit provides the information base from which the company can start to control and improve upon energy Usage.

Jan 1, 1983

A new bench blast design method and its realization with the assistance of the computer is introduced. The basic design principle is to define a rhomb cell, called fully- fractured zone, through a series of full scale bench crater tests and apply this geometric pattern in multi-hole, multi- row blast design. To illustrate the design method, the optimization process and assessment of blast performance are presented in the context of a case study.

Jan 1, 1992

This paper discusses basic practices of operation applied to raise drilling. It draws attention to critical areas that tend to be neglected. A brief history covers development of raise drills. The elements of the equipment, derrick assembly, drill string and reamers are ex- amined. Particular emphasis is on the drill string. It is concluded that manufacturer and operator can benefit each other by closer interchange of ideas.

Jan 1, 1977

A simple and rapid method for delennining gold and silver in carbon samples is described. The method involves dissolution of carbon ash in a strong oxidising medium of aqua regia and hydrofluoric acid. Gold and silver are determined in the resultant solution using atomic absorption speetrometry (AAS). The method is efficient and reproducible. Gold results are comparable to the standard fire assay results, with agreement of results within ± 5 per cent. The co-efficients of variation for gold and silver are 0.37 and 0.39 per cent respectively for six replicate analyses. The analysis of gold and silver in a batch of ten carbon samples can be completed in approximately four hours.

Jan 1, 1992

By P Hayes, B Zhao

A range of materials are treated in zinc fuming processes to recover metal values and produce benign slag waste products. The selection of the optimum process conditions in these various technologies can be greatly assisted by the use of a chemical thermodynamic model of the system. In this paper the effects of slag chemistry on the liquidus temperatures, subliquidus phase equilibria and thermodynamic properties are described by a FACT model of the ZnO-PbO-FeO-Fe2O3-CaO-SiO2 system. In addition new experimental data on the effect of Al2O3 on the liquidus are presented. The implications of these findings for plant practice are discussed.

Jan 1, 2000

By Tapp BA

Australia, considered an energy and mineral resource rich country, is poised on the verge of a major mineral industry 'boom'. It has been repeatedly emphasised that this growth in the mineral industry will form the basis of future economic development. Currently the mining and mineral processing industries use some 32% of the annual primary energy consumption in Australia. This share, although large even now, will increase with the realisation of the 1980's production expansions to 40% by 1985. Two metal industries dominate the energy scenario; iron and steel and aluminium. Major expansions in the local industry will be dominated by the aluminium industry. This highly energy intensive industry has planned major increases in metal production throughout the eighties. The implications of exporting cheap energy to pay for expensive oil imports, the ramifications on Australia's infrastructural ability to supply these major energy needs and the other options that might be

Jan 1, 1981

By Smith P

The past 20 years have seen the replacement of hydraulic control of longwall mining systems by the neater. smaller and better controlled electronic units.Early problems of moisture and other effects on reliability were overcome to see electronically controlled supports chosen for Corrimal Colliery ten years ago. Lessons from Corrimal and elsewhere, with following improvements and sophistication led to wider use as exemplified by Meco and other electronically controlled supports used in more recent installations in New South Wales, Queensland, USA and Czechoslovakia of the total of over 80 electronically controlled support installations worldwide in the past decade. Present work is toward a fully "integrated face" of British Coal by 1993, incorporating the Meco automatic face straightening system already due for practical use in the UK later this year. However the manless face still appears to be some way off although the present minimum crews and close monitoring, including early warning, are promising stages.

Jan 1, 1991

By R G. Barker, N Mortimer

In New Zealand, platinum group metals (PGM) occur in three main geological environments of economic interest: layered mafic igneous complexes, the Dun Mountain Ophiolite Belt, and in association with placer gold deposits. Most of the layered mafic complexes with PGM potential occur in the Median Batholith. These include the Longwood (Permian), Bluff (Permian), Riwaka (Devonian) and Rotoroa (Jurassic) igneous complexes. Exploration of the Longwood Complex discovered PGM associated with gabbroic rocks. Best assays to date include a 1 m drill intersection of 1 g/t Pt + Pd and float rock with 3.0 ppm Pt and 3.3 ppm Pd. The Greenhills complex at Bluff consists of basal dunite overlain by wehrlite and gabbro. PGM occur with chrome spinel in the basal dunite and Pt geochemical anomalies have been identified associated with the wehrlite-gabbro contact zone. The Greenhills complex has some similarities to Alaskan-Ural type complexes.Reconnaissance exploration in the Dun Mountain Ophiolite Belt has identified PGM geochemical anomalies, but no follow-up work has been carried out. During the late 1800s and early 1900s, PGM were recovered as a byproduct of placer gold mining in Southland. Placer gold prospects with PGM potential include the Waiau River, deposits flanking the Longwood Complex and some Southland beaches.

Jan 1, 2002

Taiwan is situated between Ryukyu and the Philippines with 35,960 sq. km of area, being slightly larger than Belgium It has roughly a spindle-shaped outline with a longitudinal axis extending in a roughly north-south direction. Geologically, Taiwan is extremely complex in terms of its tectonic setting in the convergence zone between the Asian continent and the Philippine Sea Plate. To the east of Taiwan, the Philippine Sea Plate subducts beneath the Ryukyu island arc, and to the south of Taiwan the Philippine Sea Plate overrides the Asian plate along the Manila Trench. Taiwan, therefore, occupies an unstable region between these two well-defined subduction systems of opposite polarity (see the following block diagram).

Jan 1, 1987

By Brown K, Francis D

The Yallourn Open Cut Mine has recently commenced mining operations in the new East Field which will supply the 1450MW Yallourn W Power Station for the rest of its 30 year design life. The authors describe the design and implementation process followed during the rehabilitation of the areas disturbed by works associated with mining in the East Field. One area of the East Field, the old external overburden dump, has been of particular interest and is discussed in detail. A discussion on the fire protection considerations is included as these are critical and often misunderstood as being contrary to good rehabilitation design practice. Finally, the development of a master plan for the rehabilitation of the Yallourn Open Cut in general, incorporating the East Field work, is discussed.

Jan 1, 1992

By Jackson E

The general level of awareness amongst members of the professions that they are faced with an increasing number of claims for breaches of their professional duty was dramatically heightened by the decision of Rogers J. at first instance in Cambridge Credit Corporation v Hutcheson (1985) 3 ACLR when the auditors of the failed company were found liable for breach of contract and faced a damages award of $145 million - well in excess of their insurance cover. No comfort should be found in the fact that this decision was overturned on appeal, for that result rested on the issue of whether there had been a causal connection between the breach of contract which had occurred and the loss suffered rather than on the fundamental principle of auditors' liability.

Jan 1, 1989

It is a well known fact that the best method of rock reinforcement is to avoid physical ground support. This goal can be achieved by means of: - Increasing the rock structural strength - Geological definition and forecasting. - Sequencing the excavation - Smooth blasting In many cases however, extra ground support is needed in order to maintain safe working conditions. In an open pit, the structural strength of rock cannot be increased by lowering the pit walls due to economical reasons. Economy demands steeper walls and less waste to be hauled to the dump. The geological conditions can also often be extremely poor and unpredictable. For excavation sequencing and smooth blasting there are good possi- bilities, such as cleaning of the pit walls after the main excavation, arul- ing of long small diameter straight inclined holes, use of smooth blasting techniques and lightened explosives.

Jan 1, 1989