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By Kubik K

This paper reviews the historical data on relative height changes of landmasses with respect to sea level for Pacific Rim countries.It discusses existing theories of the Greenhouse effect, and the interaction with the vertical movements of the continental plates which leads to different effects for different places. Possible future scenarios are described and directions for future research and measurement programs are given.Relative sea levels are governed not only the increase of water from deglaciation but also by a range of other factors such as variable water storage in lakes and the atmosphere, thermal expansion of the ocean, ocean currents, and the shape of the ocean and the continents. Sea floor spreading, for example, is ultimately more significant than deglaciation in sea level control but is generally much slower.

Jan 1, 1990

The mineral sands industry in Australia can contribute much more sig- nificantly to economic development beyond the year 2000 by increased production of constituent minerals such as ilmenite, zircon, rutile, leu- coxene and monazite from existing and new resources, and especially from downstream processing to intermediate and finished products based on these resources. The end-use areas for mineral sand-based products include those products whose demand is tied to general economic growth, such as paints and plastics, and refractory bricks for the steel industry. High techno- logy applications such as zirconia ceramics and super-magnets are indica- tive of new developments in technology which provide considerable scope for expansion at higher rates than overall western world economic growth. An optimistic outlook for the industry is outlined, based upon a brief review of opportunities.

Jan 1, 1988

By R Willis, D Cooke, G J. Davidson

Mine-groundwater interaction at the Pasminco Rosebery Mine (PRM), western Tasmania, deserves special attention due to the unique climate and mining environment present. High rainfall and low evapotranspiration result in an excess of water, an uncommon problem at Australian sulfide bearing mines. Research is being undertaken to delineate current subsurface fluid flows and predict future fluid flows in order to improve management after mine closure. Acid mine drainage generation is well developed in abandoned mines throughout the area. If acid mine drainage is not controlled after mine closure, significant environmental degradation could occur in the receiving waters of the Pieman River system. The study area encompasses the heavily forested Mount Black, and underlying PRM workings. Groundwater flows beneath Mount Black through a crystalline fractured rock aquifer with faults and underground mine workings observed to act as the major hydraulic conduits. Recharge is controlled by local precipitation, and the ultimate discharge is thought to be the Pieman River system, which forms the topographic low in the area. Slug tests have been used in conjunction with the mineÆs extensive geotechnical database to spatially evaluate variation in hydraulic conductivity. In fractured rock terrain associated with mining, rock quality designation data can be a useful tool in delineating areas of similar hydraulic conductivity when combined with conventional hydrogeological methods. A GIS, mine planning software, an environmental and a geological database are linked to form the input for groundwater modelling.

Jan 1, 2003

By Ren T. X, Jozefowicz R

In many branches of engineering, there has to be an understanding of the motion of fluids in order to solve problems. Many safety and health problems in the mining industry are typical examples that involve the understanding and analysis of fluid flow, such as explosions, the spread of fires, dispersion of gas and dust, and ventilation patterns. Computational Fluid Dynamics (CFD) is concerned with the use of computers to produce information about the ways in which fluids flow in given situations. Until recently CFD has been widely applied to a variety of industrial sectors and increasingly to problems in the health and safety areas. With the arrival of more powerful computers and CFD packages, CFD techniques are no longer practised solely in a research environment, but can be used by engineers in many industrial fields. This paper introduces the basic concepts and general procedures involved in the use of CFD technology. A comparison is given as a guide to the major features of a number of widely used commercial CFD codes. Areas of potential CFD applications are identified in a range of safety and health problems in mining industry. An example is presented to illustrate the use of this technology. It is believed that the exploitation of these areas using CFD approach will contribute significantly to the solution of today's many mine health and safety problems.

Jan 1, 1995

By Cox A

A key concern both in public perceptions of the environmental performance of the mining industry and in the development of policy relating to mining activities is the state in which the areas may be left at the completion of mining operations. There is, in effect, concern that the transient economic benefits of mining are enjoyed by the few, while the 'scars' may remain for all. While the techniques of mine rehabilitation have improved rapidly in recent years, an important set of economic issues has generally been neglected.In this paper, the economic and policy aspects of mine rehabilitation are examined. The key issue addressed is how to determine when expenditure on rehabilitation should stop. The answer to such a question requires consideration of the full range of social, as well as private, costs and benefits of rehabilitation at a particular site. Clearly these costs and benefits will vary between sites. From both an economic and policy perspective it is important to establish whether the additional gain from more rehabilitation would exceed the additional cost.It is concluded in the paper that the technical feasibility alone does not justify a paeticular level of rehabilitation activity and expenditure. While more rehabilitation at a particular site may be technically feasible, the additional expenditure incurred in undertaking that rehabilitation may result in little extra benefit. This conclusion has important implications for government policy, particularly with respect to establishing the goals for rehabilitation, criteria for successful rehabilitation and enforcement of rehabilitation objectives.

Jan 1, 1992

By Landy D. M, Ward M. O, Power W. L

Geological structures are irregular and intricate, so creating a 31) solid geology model is a complicated process. A software system can only partially automate this process, since geological knowledge and experience are required. Therefore, the interaction of a geologist is critical for such a system. This paper discusses some useful advanced functions for enhancing the visualisation and manipulation of 3D solid geology models: flexible attribute display, multiple views, auxiliary display objects, and geologically sensitive operations. It also describes some experiments to explore the effectiveness of these functions and presents sample output. Most existing 3D solid geology modelling systems are implemented in an ad hoc way, which greatly reduces their reusability and extensibility. This paper presents a generic framework for 3D solid geology modelling systems, which is based on object-oriented technology. The deficiencies of current systems may be improved by using this generic framework. A modelling process based on drillhole data is discusses as a case study.

Jan 1, 1995

By J Zeni

In 2001, the Springvale Coal Mine determined a requirement for a 360 m deep vertical airway to ventilate ongoing underground longwall mining operations. The project, referred to as the Springvale No 3 Ventilation Shaft, was completed in 2003 - 2004 by blind boring a 4.25 m diameter hole from the surface to the coal seam at 360 m depth. The shaft was completed with a 3.5 m inside diameter lining made from a continuous watertight steel and concrete composite pipe. Presented from both the clientÆs and the contractorÆs perspective, the following paper describes the process of constructing a blind bored ventilation shaft for this application. Beginning with the clientÆs definition of the requirements and specifications for the shaft, the paper describes the steps followed by Springvale Coal prior to awarding the contract. Springv aleÆs process involved a thorough site investigation including procurement of geotechnical data for prospective contractors and the management of issues relating to safety, quality and the environment. The clientÆs view is followed by a description of the planning and works performed by their nominated shaft drilling contractor, Ardent Underground Pty Ltd.The contractorÆs description of the works includes the details of the blind shaft drilling and lining construction process used for this application. The design of the shaft lining installed at Springvale Coal was the first of its type to be used in Australia. The successful installation of a watertight composite shaft lining and the safety of the method, which did not require any personnel to enter the shaft or the mine, were among the positive outcomes from the project.

Jan 1, 2005

IN any assay office it is of paramount importance to keep the men interested in their work; and in order to do this, men on routine work, such as lead, zinc, and sulphur deterrrrinations, slag analysis, etc, should be changed around monthly. This gives some variety and helps to keep a man's interest on his work, so that better work results. It may be maintained that to keep a man on the same class of work indefinitely makes him more expert at his work. This is certainly true; but in assaying, where accuracy is so essential, it is absolutely necessary for a man to keep his mind on the work, and not 'get' into a mechanical method of working. He is also on the alert to discover means for shortening his analytical methods, and his capacity forwork is increased. Another advantage is that the men get a good all-round training, and one is never at a loss to replace a man on any class of work when he is absent from any cause. This tends to smoother and more efficient running of the assay department. In industrial assaying it is often advantageous to have a result quickly, so that it will be of maximum benefit in the running of some part of the plant, In such a case it pays to sacrifice a little accuracy to speed up a method. The shortest method is less costly, and a quick approximate method is all that is required to give the superintendent the requisite information. Time is thereby saved, and the cost is less. In carrying out assaying for any large industrial plant, such as a smelting works, there is always a tendency for superintendents running the different departments to send in more samples for assay than are absolutely necessary when no system of costing is in operation. Some of these samples may involve a lot of work and heavy expenditure, as, for example, the estimation of only one impurity in a sample of refined lead. If the superintendent knows that the cost of assaying all samples sent in by,him is charged up directly against...

Jan 1, 1922

By Eri G

Ok ledi Mining Limited underwent a major transition from radio based truck dispatching to computerized dispatching for its equip- ment fleet in October, 1996. Modular Mining's Computerized Dispatch System was selected based on reputation and superior customer support. Modular's dispatch system is a fleet management system that uses computer, data communication and global positioning sys- tem technology to produce automatic, optimized haul truck as- signments. Optimization is achieved by equally distributing trucks to shovels so that truck queuing and shovel idling times are mini- mized. Computer illiterate mine operations personnel had to overcome a rather steep learning curve to use the high technology equipment. fortunately the system was able to be configured to use bitmap

Jan 1, 1997

By Simmons SF, Fleming J

Alteration and mineralisation at the Island Copper deposit is related to the intrusion of Early Jurassic quartz feldspar porphyry dykes into surrounding comagmatic Bonanza volcanic rocks. The pyrophyllite alteration zone forms an upward flaring cone, largely hosted within a breccia body that c ross-cuts the Cu, Mo, and Au-rich ore shell. This alteration zone contains pyrophyllite, dumortierite and diaspore and resembles alteration occurring in some high-sulfidation deposits, but which is barren. Fluid mineral equilibria and fluid inclusion studies indicate formation at approximately 300 ¦C from fluids dominated by steam and gases. These fluids appear highly acidic, but sulfur poor, leading to extreme base leaching within the breccia body and surrounding rocks.

Jan 1, 1995

The (SA Mine at Cobar produces a mix of copper and copper lead and zinc ores fran long hole open stopes. Primary jaw crusher product is fed to two parallel primary autogenous mills followed by a secondary ball mill. Each mill operates in closed circuit with cyclones. Grinding equipment and the main operating variables are described. Copper lead and zinc flotation concentrates are produced sequentially. The control systems and operating strategies are described.

Jan 1, 1983

Project managers must juggle many aspects to bring their project in on time, on budget, and in accordance with the aims of the project owner. Whether the project is a mining feasibility study, a technology implementation or a construction project, it falls to the project manager and his or her team to deal with risk from two standpoints, which may be at odds with one another. First, a project team must deal with risks to the project itself û that is, risks to on-time, on-spec and on-budget delivery against the value promise made to the customer. Second, there is the management of risks within the subject matter of the project, undertaken on behalf of the customer. The project manager cannot dodge this responsibility; yet there is a tendency (particularly in smaller, in-house studies) to avoid digging too deep, possibly for fear of what may be uncovered! This paper investigates the responsibilities of project teams in regard to risk management and reporting. It examines ownership of project risk; the nature of risk management activities undertaken by the team during the course of a project; and outlines some controls to ensure that the two opposing arms of project risk are reconciled for the benefit of both the project team and the project owner.

Jan 1, 2007

By Fradd WP

South Australia pioneered metal mining in Australia and was the main source of copper for several decades. Gold discoveries and mining also contributed significantly to the development of the Colony. Across the State can be seen the holes, the mullock heaps and, in some instances, the remnants of machinery of the past era. In this, the centenary year of the discovery of the Teetulpa goldfield, considered by some to he the most significant discovery of gold in the State, it is appropriate that we should present a paper on the history of gold mining in South Australia. South Australia has not been a major producer of gold with recorded production a little in excess of 15 million grams (15 t). This represents about 0.25 per cent of the Australian total and ranks last of the States of the Commonwealth. The outstand- ing feature of gold production in South Australia has been the succession of short periods of rela- tively high production immediately following a discovery, with payable dirt being quickly exhausted, a fact clearly illustrated by the graph of South Australian gold production (Figure 1).

Jan 1, 1987

There has been considerable attention in the literature to coarse sizing by wet and dry screening, but these methods have not proven to be applicable to the calculation of screen capacities for fine wet sizing, desliming and media recovery: A method is presented for the calculation of the size of screens for such duties, being based on the mean particle size of the oversize material on the screen which reflects the surface area from which the fines or media must be removed. Similarly for dewatering, it is the area from which the water must be drained. Desliming, media recovery and dewatering are each considered along with water require- ments both with the feed and as wash water.

Jan 1, 1984

The mineral sands industry in Australia can contribute much more sig- nificantly to economic development beyond the year 2000 by increased production of constituent minerals such as ilmenite, zircon, rutile, leu- coxene and monazite from existing and new resources, and especially from downstream processing to intermediate and finished products based on these resources. The end-use areas for mineral sand-based products include those products whose demand is tied to general economic growth, such as paints and plastics, and refractory bricks for the steel industry. High techno- logy applications such as zirconia ceramics and super-magnets are indica- tive of new developments in technology which provide considerable scope for expansion at higher rates than overall western world economic growth. An optimistic outlook for the industry is outlined, based upon a brief review of opportunities.

Jan 1, 1988

By D Lees

Safety is paramount in the underground mining environment. The mining industry has for many years focused on injury prevention in the workplace through procedures and training. In the area of control of major accident events that could result in single or multiple fatalities, and serious injuries, the mining industry approach has concentrated mainly on past experiences and lessons learnt. However, in the last 20 years, other high hazard industries, such as the chemical process industry and oil and gas industry have developed the Safety Case approach, using systems safety techniques and risk assessment as a means of identification and control of major accident events. The Safety Case approach is now being introduced into Australian underground mining. This paper describes the Safety Case approach and how this can be adapted to underground mining. This is a holistic approach and assists in ranking significant risk contributors and prioritising risk management efforts. The discussion includes how the Safety Management System interfaces with the Formal Safety Assessment in effectively controlling the hazards. It provides examples from actual case studies conducted by KBR, and suggests ways forward for the industry.

Jan 1, 2003

Beach sands on the Morobe coast of New Guinea contain significant amounts of chromite. This chromite, together with the more abundant associated minerals such as olivine, enstatite, tremolite, antigorite and feldspar has been de- rived from rocks of the Papuan Ultramafic Belt and transported to the beaches by three rivers, the Paiawa, the Saia and the Sesimbai. Of the hundreds of samples taken, 26 have been analysed mineralogically and chemically in some detail. On this basis, five groups of samples, four on- shore and one offshore, representing character- istic mineral assemblages, have been recognized. The chromite grains themselves have been exam- ined to determine variations in amount and in the Cr/Fe ratio, since this is of economic importance. Much of the chromite fails to reach a high Cr/Fe ratio as a result of magnetite rims around chromite grains. The precious metal content of the sands is negligible.

Jan 1, 1973

This paper sets out a number of means by which professionals can reduce or eliminate the risk of professional liability whether as directors, employees, partners, independent consultants or contractors. A relationship between client and professional is commonly cited as an example of a fiduciary relationship: the professional "undertakes or agrees to act for or on behalf of or in the interests of' the client "in the exercise of a power or discretion which will affect the interests of that other person in a legal or practical sense."2 As a fiduciary, a professional must ensure that his or her exercise of power does not result in a position of ascendancy or undue influence over the client. Also, a professional must avoid situations where there is scope for even the perception of potential conflict between his or her professional duty to the client and his or her own Interest.

Jan 1, 1995

By Dunn J, Nguyen G, Graham J

A pyritic gold concentrate from the Golden Mile, Kalgoorlie, was roasted over a range of temperatures in a pilot scale fluid bed reactor. The calcines were subsequently cyanide leached. Mineralogical studies of the con- centrate, calcines and leached residues were also undertaken. Calcines produced at 500'C gave the poorest gold extractions and high cyanide consumptions. Gold recoveries of approximately 90 per cent were obtained from calcines produced at 550-600'C but higher roasting tempera- tures resulted in an increase in the residual gold content of the leached calcine. There is some evidence of flash smelting of the pyrite at the higher roasting temperatures and encapsulation of gold particles. Mineralogical examination of the calcines shows that the mechanism of oxidation is temperature dependent. At 500'C pyrite is directly oxidized to hematite with a concentric layered texture which appears to inhibit lixiviant access to enclosed gold particles. At higher temperatures the conversion sequence pyrite-pyrrhotite-hematite produces a spongy calcine which al- lows easier penetration by the leaching medium.

Jan 1, 1991

There is considerable economic incentive to increase the angle of open pit walls so as to reduce the total volume of waste to be moved to gain access to an orebody. However, a number of slope failures has increased the awareness of mine operators to the potential and consequences of slope failure. Sophisticated methods for the analysis of slope stability have been developed but they rely on an understanding of the appropriate parameters to describe the structural properties of the slope materials. Unfortunately, these properties change with time.The excavation of an open pit mine removes the constraint and weight of the overlying material and allows the newly formed slope to release previously locked in stress. The release of this stress allows the opening of joints and leads to a significant reduction in bulk modulus. The rock mass is also further affected by damage from nearby blasts. Such damage is cumulative and further reduces the modulus of the near surface material and weakens the bonds between structural elements in the slope.

Jan 1, 1992