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A narrow (200-300m) zone of amphibolite facies metamorphic rocks underlies the Papuan ophiolite near the Musa-Kumusi divide, SW of Popondetta, Oro Province. The amphibolite rocks are bounded up-section, to the NE, by peridotite and gabbro of the ophiolite; and down-section, to the SW, by mafic greenschist, which in turn overlies blueschist facies mafic schists of the Emo Metamorphics.Amphibole compositions within the narrow contact zone show a strong chemical zonation which reflects a steep thermal gradient, with maximum temperatures >800¦C at the peridotite contact. The zonation is recorded in Ti content and A-site occupancy, relative to Al'¦

Jan 1, 1994

Through the stress synthesis of many exanples of macrostructure from eastern to western parts of China, it can be concluded that in Chinese tectonics there are two push- twisting forces, one of which ("Rl", from SE to NW) came from the Pacific Ocean plate thrusting over the Chinese continent plate in the eastern part of China; the other ("R2", from SW to NE) resulted from the thrusting of the India plate. The meeting line could be situated along the belt from 104¦-106¦E longitude in the middle part of China. To the south of Qinling the meeting line was an abyssal and giant fault situated from Longmen to the Er Inland Sea where the Tibet-Gansi fold system was intersqueezed to the Sidluan platform; to the north of Qinling, situated on the Fengxiang subsidence of the Eerduosi basin, the meeting line was located about 105¦E in Mongolia and appeared in the form of an arcuate structure, i.e. the Mongolia arcuate structure, which could extend to Beijiaer Lake towards the north. A new special type of structure named rotation-apart structure occurred from Gansu, Qinghai province to Ningxia, Neimeng autonomous region, in the west of Shandong province and in the western part of Chaidamu Basin.

Jan 1, 1987

By J Barnes

During September 2000, Nabalco management identified the need for a corporate system to deliver its key performance indicators (KPIs). In June 2001, a need was also identified to replace the existing metallurgical accounting system. After a review of the technologies available, the decision was made to develop the systems in-house, in preference to purchasing commercial software packages. This would allow much greater control over the structure, and provide for an iterative, concurrent development process between software and key business developers. This has proven invaluable in the development process. The purpose of the KPI system is to provide a unified reporting tool for all performance indicators. These indicators include production, safety, health and environment, personnel, costs, continuous improvement initiatives and opportunity losses. All of these disparate measurements are brought together into the KPI system and used to determine the performance for each department or area. The general principles of the balanced scorecard business approach (Kaplan and Norton, 1996) are applied to achieve a performance measurement for each area within Nabalco. The new metallurgical accounting system (MA) is a SQLServer database with web page and Excel interfaces. The database is structured around daily inputs of all measurements and calculations. The data is stored and adjustments and reconciliations can be made to this data as required. The focus is on accounting rigour, with all adjustments recorded in the database to allow for full auditing. The structure of the data focuses on the five input/output streams (bauxite in, caustic soda in, fuel oil in, residue out, and alumina out). In-circuit inventory provides a secondary measurement on which to check and calibrate the MA system. The KPI and MA systems were developed using Web technologies and are available to any internet-enabled device with Internet Explorer installed. This removes the need for software rollouts and user training. This will promote the wide use of the systems throughout Nabalco and Alcan.

Jan 1, 2002

By Getliffe RK

It is becoming more and more difficult to operate mineral and metal processes profitably, as operating costs rise, quality demands in-crease, international competition becomes more fierce and Government charges remain at their current levels. Profitability today depends upon efficient operations, which can only be achieved through precise and dependable con-trol of each process unit comprising thetotal plant.Modern process control systems utilise distributed architecture with microprocessor-based controllers, data acquisition devices and VDU operator stations. Honeywell intro-duced this control technology in 1975 with the "Total Distributed Control" System. Now, building on the proven performance and re-liability inherent in TDC hiway modules, Honeywell has extended the TDC system to inte-grate both management information and control by providing distributed processing modules on the new TDC 3000 Local Control Network (LCN).

Jan 1, 1985

This report chronicles the historical development of longwall mining in the United States and speculates on future developments to the turn of the century. Five eras of technological development during the modern period are described and analyzed. These eras discuss the development of (1) mechanized extraction, (2) self advancing roof supports, (3) high capacity roof supports, (4) shield supports, and (5) system automation. Current trends are analyzed in terms of: longwall utilization, production capability, support capacity, face widths, and new technological developments. From these analyses, the future of longwall mining to the year 2000 is speculated. It is concluded that longwall mining will continue to grow in importance during the next decade and that the next major technological milestone will be the realization of a fully automated longwall mining system.

Jan 1, 1992

Before commencing design of a coal prepar ation plant, it is essential to have detailed information of the raw coal to be treated to- gether with a clear understanding of the products required. Prediction of raw coal size distribution, particularly the amount of fine material, is difficult and the methods employed should be large scale pilot plant studies or techniques to simulate coal degradation and shale breakdown in water. A detailed knowledge of well proven coal preparation processes and new developments allows processes and process combinations to be compared to'obtain the maximum economic recovery when using lower cost, less efficient processes within acceptable limits. Equipment should be selected bearing in mind its precise application and the location where it is installed. Plant layout should be carefully studied to minimise equipment requirements and to simplify construction. Measurement, control and automation should be an integral part of plant design in order to obtain the optimum performance of the processing equipment.

Jan 1, 1974

By Williams RC

Overlying the coal deposits of the Sydney Basin are several lakes and other bodies of water. These include the Pacific Ocean, Lake Macquarie, the Tuggerah Lakes and the stored waters of the dams of the New South Wales Metropolitan Water Sewerage and Drainage Board. The coal beneath these bodies of water amounts to hundreds of millions of tons. Colliery workings have approached these areas of water and in some instances first 1"orkings of bord and pillar have taken place oi_eshh the water. he problem which now faces mine manage- and other interested authorities involves the determination of the maximum ;mount of coal which can be safely extracted from beneath the water. There are many factors to be considered including the depth of cover, seam thickness, geological details and strata movements.

Jan 1, 1972

By Quemard D, Troncoso J

The Gordonstone Project with a capital cost in excess of $500 million will become the largest underground coal mine in Australia. The project development decision was taken on 31 July, 1990 and at 31 May, 1991 construction was approximately 35 per cent complete. The first train of processed product coal will be railed to Gladstone during December 1992. The general theme of this paper therefore will address the planning and development processes at Gordonstone particularly the interrelatedness of technical, production, construction and environmental disciplines to ensure success during operations.

Jan 1, 1991

By L Wsrell

During recent years the iron ore industry has experienced a continuous consolidation trend following increased merger and acquisition activities. Analysing and evaluating these mergers is important in order to establish potential effects. The purpose of this paper is to analyse the price effects caused by the merger between Rio Tinto and North Ltd in 2000. The merger was cleared by the European Commission, as well as the Australian Competition and Consumer Commission, shortly after its announcement. The analysis will be conducted using a simulation model based on a proportionality calibrated almost ideal demand system, which uses the premerger situation in order to estimate the post-merger outcome. The relevant market is defined using shipments data. This is followed by the simulation model applied to the defined relevant market. The results show that the concentration on the market, given by the HHI, increases approximately 15 per cent, and that the market share of the new companyÆs reaches almost 20 per cent. Compared to the CommissionÆs assessment the results indicate a more concentrated market and thus a higher concern for possible competitive effects. Furthermore, the results suggest that the predicted average market price increase from the merger is 1.6 per cent. However, the merged firm is able to increase their average price by 5.1 per cent.

Jan 1, 2005

The paper describes a simulating method.for ground water contamination originating from industrial and mining activrty. The finite difference model simulates heat, mass and solute transport. The applied stochastical method for dispersion provides more accurate solution of mass transport modelling. This method gives a more realistic approach of chemical processes in an aquifer depending on temperature.

Jan 1, 1988

The paper examines the difficulties encountered by objectors to mining privilege applications. It describes the various involvements of the environmental defence society in the mining controversy and makes some comment on the proposed amendments to the Mining Act 1971.

Jan 1, 1981

This paper summarises the current status of the mining sector in Poland in terms of vertical transport system safety. Selected results of research programs conducted at the AGH-UST relating to mine hoist system safety are reviewed. The conclusions support the notion that the costs of vertical transport systems can be reduced, while at the same time maintaining the required safety and reliability levels. Novel solutions: movable fender beams HWR, linings modar« and the integrated shock absorbers PHH for conveyance guiding systems fully confirm this hypothesis.

Jan 1, 2005

By P J. Hansen, D G. Franklin, M E. Trim, J V. Myers

The Northern Sewerage Project (NSP) is an upgrade to one of MelbourneÆs ageing, under-capacity trunk sewers. It will reduce the volume and frequency of wet-weather overflows to the Merri and Moonee Ponds Creeks and facilitate new housing developments in the northern suburbs of the city. A total of 12.4 km of tunnel and eight vertical access shafts will be excavated as part of the two project stages: Stage 1 (NSP1) will be owned and operated by Melbourne Water (MW) and Stage 2 (NSP2) will be owned and operated by Yarra Valley Water (YVW). The owners require the project to have a service life of 100 years, a requirement significantly beyond many of the current Australian Standards, which aim to achieve service lives greater than 60 years but are typically assumed to achieve 40 to 60 years. Because of the potentially corrosive natures of the external environment along the tunnels and the internal sewer environment, durability was a key concern for NSP1 and NSP2. Stringent specifications were applicable to the tunnel lining systems. This paper describes the corrosive environments impacting NSP1 and NSP2, explains the key design differences between the two stages and details the lining systems considered and selected to achieve the clientsÆ desired 100-year service life. The project design is complete and construction began in 2007.

Jan 1, 2008

In 1976, The Zinc Corporation Limited Broken Hill set up a plant to re-process a hill of tailing (Mt. Keast) from the original treatment operations. With the likely disappearance of this source of feed in 1985, an investigation was initiated to determine what other feed sources might be available. This involved searching through old records and photographs as well as a subsequent drilling campaign. The paper briefly covers the history of treatment operations and describes, as a result of the information obtained, the likely future sources of feed.

Jan 1, 1983

By Walker G. S

Infrared and Raman spectroscopy have been used to study a range of solid state and aqueous solution species which are of interest in extractive metallurgy. In the solid state new Cu(II)/CN'/NH3 complexes have been detected, iron impurities in kaolin characterised, aluminium substitution in hematite and goethite quantified, and the crystallinity and orientation of zircon determined in heterogeneous crystals. In aqueous solution metal cyanide complexes and equilibria were readily characterised, the thermal decomposition of SO2 monitored and products identified, and complexation of AI(III) by hydroxycarboxylates observed. Attempts to monitor the early stages of the gelling of silicate solutions were less successful, with only changes in the gel being detected. However, the degradation of 12-tungstosilicic acid was readily monitored as a function of both time and pH.

Jan 1, 1996

The Ida Valley in Central Otago is one of series of parallel basins filled with freshwater sediments. The basins are in fact tectonic depressions superimposed on NE trending grabenlike structures which occur in the area and are the result of block faulting possibly initiated in Cretaceous times and concluded in late Tertiary and early Quaternary. In Central Otago this tectonic event affected metamorphosed rocks belonging to the eastern facies of the New Zealand Geosyncline and collectively known as the Haast Schist Group. These rocks constitute the basement and the shoulders of the tectonic depressions. The Ida Valley occupies the depression wedged in between the Raggedy Range to the NW and the North Rough Ridge in the SE. The valley is approximately 38 km long, 3 to 7.5 km wide and is drained by the NE flowing Pool Burn, which meets the SW flowing Ida Burn. The resulting unified stream flows into the Manuherikia river which drains the next door depression to the NW. The present work deals with the Ida Valley basin and more specifically with the geology studied within two Prospecting Licence areas held by Gold Mines of NZ Ltd on the southeastern flank of the valley.

Jan 1, 1977

By D Craw

Interactions between structure and lithology in the Hyde-Macraes Shear Zone controlled the style of gold mineralisation at the Macraes mine. Large volumes of rock in some mine pits have most gold disseminated in hydrothermally altered schist, rather than in quartz veins. Mineralisation was initiated in the latter stages of metamorphism. Pods of massive schist rich in quartz and feldspar are surrounded by more fissile schist consisting of interlayered micaceous and quartzofeldspathic schist. Later shears have been partly controlled by the micaceous schist, and anastomose around pods of more massive schist. Micaceous schist was replaced by pyrite and arsenopyrite, accompanied by recrystallisation of phengitic muscovite under lower greenschist facies conditions. Gold occurs in sulfides and with microcrystalline quartz formed during minor silicification. Massive schist is locally mineralised along sulfidic microshears which have phengitic muscovite largely illitised under sub-greenschist facies conditions. Mineralised massive and micaceous schists were overprinted by cataclastic shears, with addition of graphite and more sulfides. Mineralisation occurred during a transition from ductile to brittle deformation regimes as the schist was uplifted in the late Jurassic.

Jan 1, 2004

By Mauk JL, Arehart GB, Mathews SJ

The banded nature of the quartz veins which form the Empire lode at the Golden Cross mine, is perhaps their most striking feature. Petrographic studies show that significant differences occur between the bands in terms of textures, quartz grain size, calcite, adularia and kaolinite content, and the form, concentration and mineralogy of sulfide phases. The 818Oqu i values of individual bands within the vein material range from 7.3-10.9%x. Calculations show that the 818Oqäa,u values can be adequately explained by temporal variations in the system temperature, boiling and/or variations in the systems fluid/rock ratios.

Jan 1, 1995

By S Holmes

Solid Energy New Zealand operates the Stockton Opencast Coal Mine, a unique deposit consisting of high quality hard coking and thermal coals. Stockton's uniqueness includes high variability of the shipment specifications, strict quality constraints, minimal stockpiling capacity in the coal transport chain and the variability of coal quality both vertically within the seam and laterally across the deposit. The process of resource proving and modelling results in a high level of understanding of the deposit to allow detailed planning to be undertaken. The use of computer aided mine planning tools is an important component of the mine planning at Stockton. Detailed planning is implemented in the field through selective mining practices and monitoring to minimise dilution and maximise recovery of the coal resource. The quality variability in the coal, the æjust in timeÆ approach of the coal transport chain and markedly varying quality specifications from shipment to shipment requires a large coal inventory and the mine to be driven by quality constraints rather than material movement capacities.

Jan 1, 2003

This paper outlines the mechanism of Stress Corrosion Cracking (SCC) and how it can cause premature failure of rock bolts. SCC occurs due to the progressive development and growth of cracks in the surface of a metal, and it is caused by the combined effects of stress and a corrosive environment affecting susceptible metals and alloys. It can occur in most metals including stainless steel. It is not a new phenomenon, but its effect on rock bolts has only been recognised recently.Rock bolt failures caused by SCC appear to be brittle failures which occur at less than the ultimate tensile strength of the bolt. In the mining industry, SCC failures of rock bolts can occur a few months, or after many years of exposure to stress and a corrosive environment. If SCC of rock bolts is suspected, then the rock bolts should be examined by a metallurgist, and steps should be taken to reduce the problem.

Jan 1, 1998