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The aim of all modelling is to replicate geological reality as closely as possible using available data. This paper is aimed at one end of the spectrum, where very limited data is combined with intuitive geological ideas to synthesise models for either target definition or for determining minimum viable mining scenarios. Interactive 3D modelling allows a satisfactory hypothetical geometry of surfaces to be assembled, and provides a fast quantitative method for generating targets. As data flows from exploration, an evolving geological model assists with the progressive evaluation of a prospect. Two case histories are described where this approach has been used successfully, the Mosquito Hill Prospect in Queensland and the Longwood Ranges Platinum Prospect in New Zealand. The possibility is also discussed of hypothetically modelling an orebody which has yet to be discovered. The proper description of an orebody is the foundation upon which all mine design and planning is undertaken. The volumetric accuracy of the model is crucial in valuing an orebody. Geologists must form a geometry which matches the conceptual view of the ore occurrence and ensure that they understand how the computer system used calculates volumes. If the underlying assumptions inherent in the method conflict in any way with the conceptual model visualised for the ore occurrence, then that method must not be used.

Jan 1, 1995

The aim of this paper is to examine the problems confronting the planner, designer, constructor and management when rehabilitating the works associated with road building- and including quarry and borrow areas. The importance of further investigation into the many factors involved, including species, methods of planting and aftercare is stressed as is the need for trained personnel and the consequential availability of specialised training courses. Emphasis is placed upon the relevance of a rational and unemotional approach to rehabilitation with respect to the landscape and to the high degree of co-ordination and co-operation between all disciplines involved.

Jan 1, 1976

By Frfas C, Parrilla F, Regife J. M

A project to develop the Zinclor electrowinning cell to industrial size is being conducted at Tecnicas Reunidas' Research and Development Centre with Spanish Ministry of Industry support. This project is the final development phase in zinc electrowinning from a chloride medium, the highest ZINCLOR technology development level prior to the industrial scale having already been reached. This paper covers the outcomes and conclusions corresponding to project Phases 1 and 2: Process Selection and Industrial Electrodes (1 m2) design and testing. The most important achievement reached is that there are presently available industrial cathodes and anodes for the Zinclor diaphragm cell giving an optimum response for zinc chloride electrowinning with unit power consumptions between 2.65 and 2.80 kWh/kg Zn, depending on the diaphragm type. Standard electrolysis conditions were: 65 g/L ZnC12, 3 g/L HCl, 160 g/L NaCl, 350 g/t Zn arabig gum as the addition agent, 36¦C, and 400 A/m2 current density. The selection of electrodes, diaphragms and organic additives for the industrial scale tests have been optimised. The complete electrowinning cell development, with electrodes having an active area of I m2, enables the evaluation of Zinclor Technology application for industrial processes.

Jan 1, 1993

The scope, pace and depth of mining is creating a need for improved ground control strategies to meet mine safety standards. Ground control and associated conservation problems relating to subsidence and the disposal of mining and metallurgical wastes can be resolved by mine filling with selected reject materials. The lack of suitable criteria to evaluate the applicability of such materials and especially cemented forms of fill is considered. Sulphide wastes, which are prone to oxidize, and cement are inexpensive mine fills, but their incorrect use can give rise to problems which are briefly described. Research work concerned with the utilization of sulphide wastes such as mill tailings, to produce fill with self-cementing properties has shown that the development of cohesion and strength is attributable to natural oxidation processes controlled by the physical and chemical composition of the fill mass. The cementing is caused by a number of oxidation products, and is most effective when the mineral pyrrhotite is present. The concepts of fill design are outlined and various criteria for assessing durability and deformational properties are proposed. Specimens prepared in the laboratory are capable of attaining unconfined compressive strengths up to 28 MN/m2.

Jan 1, 1973

By J Pearse, N Acosta, N McIntyre, M Angarita, L Camacho, C Huguet, D Arbelaez-Ruiz, J Ossa-Moreno, O Restrepo

Colombia is an example of a nation where mining makes a significant contribution to local and national economies. Due to the abundant resources present in the ground, there are good prospects for further development. However, the impacts of mining projects can include reduced access to good quality freshwater for other economic activities and/or biodiversity preservation (Ossa et al., 2018). As well as the water management challenges common to all mining regions globally, Colombia has particular challenges associated with its biophysical and socio-political traits. Land use change in many regions is dynamic including rapid development of agriculture and the development and abandonment of small scale mines. The value of ecosystem services provided by prospective mining regions also creates challenges in particular with regard to the páramos, the headwater wetlands from which about 70% of Colombia’s water supply has originated (Cleef 1981). Colombia also has particular challenges related to strong preconceptions about mining and its impacts on water. On the one hand, there is recognition that new large-scale mines are important for Colombia’s economy; on the other, there is deep distrust of the sector’s ability to operate with minimal adverse impacts (Gutiérrez-Gómez, 2017). Hence, any impact assessment is likely to face high levels of scepticism and scrutiny. Summarising the work of McIntyre et al. (2018), this abstract proposes a framework for assessing and communicating risks to regional water resources arising from the impacts of mines. The framework outputs aim to provide government and other stakeholder groups the scientific evidence needed to inform their viewpoints about mining development in the selected region, and a baseline from which to design a program of priority scientific research. CITATION:McIntyre, N, Angarita, M, Acosta, N, Camacho, L, Pearse, J, Huguet, C, Restrepo, O, Ossa-Moreno, J and Arbelaez-Ruiz, D, 2018. A framework for assessing and communicating water risks in prospective mining regions of Colombia, in Proceedings Life-of-Mine 2018, pp 49–51 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 25, 2018

Operations at two open cut mines have so far commenced on two out of the five potentially mineable seams in the Fair Hill - German Creek Coal Measures. Due to seam splitting, up to seven mining units are present in the Dysart Seam interval at Peak Downs giving a total of 12 mining units in the section. The coal is low to medium volatile type and produces strong coke. Rank increases and fluidity decreases in the southern part of the area.

Jan 1, 1974

Sophisticated pit optimisation software has allowed mine planning engineers to generate mining outlines that consider the numerous factors that have a major effect on the success or otherwise of a mine plan. The outlines are generally generated using a range of values for which one can assume a fixed mining cost and a variable revenue. During analysis, the expected costs and revenues are used to investigate the cashflow and sensitivities. Ultimately, the final pit and incremental outlines, or shells, are selected for a given expected price. This paper proposes an alternative method for incremental pit shell selection that considers the risk the mine be prepared to accept. The life of mine is divided into a number of Business Risk Periods (BRPs). The BRP represents the period of time over which the owner is prepared to invest capital. During each BRP, the mine will then operate at a selected investment cost which is generally equal to or greater than the minimum required to meet production targets. In this way, a robust mine plan can be produced which allows the mine to react to change without having to alter the incremental shell limits while maintaining a strategic risk profile. This paper will summarise factors to be considered in selection of the BRP and the incremental pit shells within the BRP.

Jan 1, 1998

By Gillies A. D S

Technology transfer is a vital requirement for increasing national capability of coal mine production in Indonesia. The term can cover the introduction of new equipment, facilities and processes and approaches to training and education. Constraints on technology transfer within the Indonesian coal mining industry are reviewed. The contributions that foreign companies working within the industry can make are discussed. It is concluded that the development of major Indonesian coal mines needs input of advanced foreign technology. The foreign mining companies are investing significant capital in operations and are permitted to import outside expertise due to some lack of national skills. Expatriate employees are expensive and have a direct effect on profitability. The success of any replacement program of foreign employees is dependent on technology transfer. There are statutory Indonesian Government directions to reduce dependency on foreign expertise over time.

Jan 1, 1995

The Argyle AK1 Pit has been operating and producing over 25 per cent of the worldÆs diamonds by volume for over 20 years. The mining boom in Western Australia is creating upward cost pressures to ArgyleÆs mining operation while the price received for its product remains flat in comparison to many other Western Australian commodities. This incongruity, which when combined with other circumstances such as the pit being close to the end of its mine life, a decline in head grades and a tightening in operational constraints caused by the pitÆs maturity, is causing the leadership team at the mine to utilise innovative strategies in order to ensure that the open pit continues to perform economically until its final closure in late 2010. The strategies that will be discussed in this paper are step change business improvement methods, localisation of the workforce, employment of Aboriginal people and the use of a clear and concise consultation process in order to provide certainty to a workforce working in a pit during boom times where pit closure is imminent.

Jan 1, 2007

Mine haul road design at Bougainville Copper Limited has undergone significant changes since mine start-up. Selection of 95 tonne trucks and the subsequent replacement by 155 tonne units is discussed, with particular reference to haul conditions within the mine. Changes to haul road design and construction practices are detailed which have lead to improved standards and tyre life. INTRODUCTION Bougainville Copper Limited operates one of the largest copper mines in the world at Panguna, Bougainville Island, in the North Solomons group of Papua New Guinea. The mine commenced commercial operation in April, 1972 and current planned production is 198 000 tonnes of material per day, of which 115 000 tonnes is ore averaging 0.46% copper. Annual total planned production is 72 000 000 tonnes to yield approximately 150 000 tonnes of copper with significant quantities of gold and silver. The mine operations workforce now consists of national employees up to General Foreman level.

Jan 1, 1982

"DEEPHOLE " or "Longhole" drilling is the name given to the drilling of prospecting holes with the pneumatic hammer drill. The drilling bit is of the same form, and is prepared in the same way as ordinary rock drill steel, and is extended to the bottom of the hole by sectional hollow rods, through which water is forced.The cuttings from the hole provide a sample of the ground drilled.Deephole drilling was developed at an American mine where the cost of diamond drilling, owing to loss of diamonds, was excessive, and proved very successful, holes being drilled as deep as 220 ft., in limestone, at a cost of one dollar per foot. The use of the method in other mines, and in a variety of rocks, has since been described in the technical literature. From the published descriptions the following data are drawn:

Jan 1, 1930

THE alkaline method for the estimation of zinc cannot, in the writer's opinion, be relied. upon to within very narrow limits between two assayers on unknown quantities of zinc. The end point is not decisive enough, and allows the personal factor toenter largely into the assay. The following investigation was undertaken to see how accurate the acid method is on Broken Hill concentrates and ores, and what should be the limit between the results of two assayers. The method adopted is as follows:Weigh sufficient amount of ore to give titration (between 20 and 50 cc.), place in tall 400 cc. beaker, cover, add 7 cc. nitric acid and heat till brown fumes cease to be evolved. Wash dock glass into assay, add potassium chlorate, evaporate to dryness on a slow fire with the beaker uncovered. When no smell of chlorine or nitric acid is observed, remove and cool. Add 100 cc. boiling water, then 7 grm. ammonium chloride, W cc. ammonia (.880 sp. gr.), boil for five minutes, filter, wash...

Jan 1, 1911

The paper examines the value of very small-scale indigenous gold mining operations to developing countries. The paper looks particularly at this type of activity in two neighbouring countries, Papua New Guinea and the Philippines, considering technical, economic, social and environmental aspects.

Jan 1, 1990

The space probe Magellan is on its way to Venus (May, 1989) and with its sophisticated radar systems will discover much more about our twin planet. There is tennuous evidence that Venus once had liquid water. Did it have life? Why was it not stable and why did liquid water not persist through the period of the dimmer young Sun? These are profound questions for us. We understand why Mars froze when volcanism terminated (Just as Earth will freeze one day) but could Earth boil if we continue to add greenhouse gases (Broecker, 1985). What will happen if 10 billion humans continue to use fossil carbon as their main fuel source? The Earth is warming fast and the new satellite data show that the oceans are warming faster than we thought. Is this just a fluctuation or is the greenhouse signal coming through the normal noise of climate?

Jan 1, 1990

By K Uchino, M Inoue

Self-potential anomalies are generated by fluid pressure gradient, by temperature gradient or by chemical gradient. On the basis of this principle, a new technique is proposed to locate the fire source of spontaneous combustion of coal by the self-potential method. In order to investigate whether this method can be applied to locate the spontaneous combustion of coal in practice, surveys of self-potential distributions were undertaken in a coal waste pile undergoing spontaneous combustion. The results showed that there is a negative centre of the electrical potential distribution in the measurement area. The potential in this centre is about 140 mV lower than that in the surrounding area. Moreover, the negative centre of electrical potential distribution almost overlaps with the high temperature zone. Therefore, it is concluded that it is possible to locate the heat source by the measurement of self-potential distribution.

Jan 1, 2005

It is argued that the capture of par- ticles by bubbles is primarily caused by hydrophobic ("structural") attraction forces. Neither dispersion forces nor double-layer forces can account for hydro- phobicity, though the latter are known to influence the kinetics of capture. The recent experiments of Israelachvili and Pashley (Nature, 300: 341-342, 1982) with hydrophobic mica plates provide the first measurements of the range and magni- tude of hydrophobic interaction forces.

Jan 1, 1984

A recently discovered high temperature (22G-2800°C) reaction between glycerol and the oxides and hydrous oxides of iron produces a green, well-crystalline complex glycerato-iron, whereas hydrous nickel oxides an) reduced by the glycerol to metallic nickel. When nickel isomorphously substitutes for iron within the goethite lattice this high temperature glyceration allows a separation of the two metals whereby the nickel can be extracted by solution techniques.

Jan 1, 1971

Three main divisions of the. Proterozoic are recognised in the North- West of Western Australia. These are referred to, in order of decreasing age as the Mt. Bruce Supergroup, the Bresnahan Group and the Bangemall Group. The stratigraphy and distribution of each is described, their relative ages discussed and a brief geological history of the whole area is Presented.

Jan 1, 1964

By E Drueppel, F M. Meyer, P N. Martens, J P

The present study shows a calculation of the amount of copper contained in the initial reserves that remains un-extracted. The study is based on data of 271 producing copper mines and includes geological parameters, mining methods used and the processing recovery. Estimations disclose that approximately 25 per cent of the metal contained in the original reserves is not extracted. One third of this value can be attributed to mining, whereas two thirds are related to processing. However, values differ for different ore deposit types and mining districts.

Jan 1, 2003

A Master of Applied Science degree course in Mining Geomechanics commenced in 1983 at The University of New South Wales, taught by extern- al (correspondence) studies. The course is aimed at graduates employed in the mining indust- ry, and especially people involved in geomechan- ics projects on a routine basis in remote locations. This kind of course is unique in Australia and is one of only two correspondence programmes available at this University. The author designed the course and nursed it through the early years, and was Director until 1986. The paper describes the teaching and assess- ment methods and also discusses aspects of admin- istration and coordination of such a course. It is concluded that an important need of the mining industry is being catered for and it appears that similar correspondence course for- mats would also be useful in other areas of the minerals industry.

Jan 1, 1986