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British Coal's Selby Complex is the newest producing mine in the United Kingdom. The reasons behind its origins, planning and design are explained. Some detail is given of equipment used, with the emphasis being placed on the unique features of its layout. The entire project has been planned and constructed over many years and the design has consequently changed, principally in response to the geology of the coalfield and improving technology. In spite of many totally unexpected difficulties, the mine, which is not yet in full production, has the highest productivity in the United Kingdom.

Jan 1, 1991

The narrow quartz vein deposits at Konongo and Ghana Main Reef gold mines in Ghana were emplaced during the plastic flow cross folding of pre-existing sub-isoclinally folded volcanic and perivolcanic deposits of Proterozoic age. The older fold structures tightened differentially according to their position in relation to the axes of the cross fold pattern giving complex outlines to the reefs in both plan and cross section.Some 4500 measurements of bedding plane linears were used in the resolution of the Boabedroo footwall structure at Konongo. The methodology developed at the Boabedroo mine was then successfully applied to other complex bodies at the Konongo and Ghana Main Reef mines.All mine development, especially stope preparation, of the folded quartz reefs at Konongo and Ghana Main Reef was controlled by the geologist to ensure that the veins were removed with as few geologically enduced hiccoughs as possible.

Jan 1, 1993

Open cut low grade gold mines form the basis of the current upsurge in the mining industry in Australia. The effect on profitability in the short term and viability in the long term requires accurate estimation of grade and tonnages. The application of the Ditch Witch Trenching Machine as a grade control tool has occurred rapidly and the machine is now a working tool in many mines throughout Western Australia.

Jan 1, 1987

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

This paper will review the experiences of both big and small exploration/mining companies (local and foreign investors), including the impediments to exploration and project development in Indonesia since the Contract of Work was first introduced there (1967 Minerals, 1981 Coal). This is seen through the eyes of a person who has been employed in a managerial capacity in large and small concerns, and more recently as an independent consultant. Comment will be made on the political, legislative and social constraints imposed by the presence of a large group of disparate artisans (illegal miners) who now form a significant component of the Indonesian mining industry; the Bre-X debacle; the impact of the recent Regional Autonomy legislation; and changes to the Mining, Forestry and Environmental Acts. An overall view (including statistics) will be presented as to how recent Indonesian developments have affected international confidence in investing in its mineral sector over the past decade and it will be placed in an international competitive context.

Jan 1, 2004

The success of the In-Plant dust collection at the Albion Reid Quarry Plant situated at Para Hills, South Australia, is discussed in the light of co-operation at the design stage with particular emphasis on the duct- work and filter design. Other dust control facilities at the Plant are mentioned.

Jan 1, 1976

Any future developer of underground mining on the Bendigo goldfield will need to understand the unique geology and gold occurrence of this field. The development and sloping system employed will be primarily designed around these unique features. Modern techniques and equipment used in narrow vein mining will be applicable in this situation.The purpose of this paper is to examine the important geological features of the field as well as the known historical occurrences of the type of gold deposition in the ore bodies. This information will point to a system of development and extraction which will accommodate these features.

Jan 1, 1993

The iron ore deposits of-the Port Hedland distract of North-Western Australia are associated with banded-sedimentary iron., formations that.form part of the local succession. of folde.d..and faulted Archaean volcanic and sedimentary. rocks., The iron formations are regarded as the pr.otore,beds or sources of.the. iron which became;.,c,o.ncentrated by supergene.,processes. to form c,omznercial grade.. iron ore deposits,, ;-ò; Iron oxide ' deposit's occurring in"situ' within' the prot'ore beds are considered to be of residual--repplacement,origin`, due to supergene leaching of gangue minerals and deposition of secondary iron oxides in their'place'. Two types of deposit have been recognized. Lode deposits are deep lenses of massive hematite located adjacent to major, fau.lts... - These; deposits are-thought-to be very.,,old' and-to: have originated by supergene processes:.. during the, long: period of_ erosion represented- by the major, unconformity between the, Archaean .rocks and the, over!.

Jan 1, 1964

By Cunningham CG

Many epithermal gold-silver deposits areknown to occur in the Neogene-Quaternary volcanic complex of the central Andean region of southern Peru, northern Chile, western Bolivia, and north-western Argentina, an area of about 300,000 km2 where these volcanic rocks constitute the dominant cover. Some of the gold-silver deposits were mined during Spanish colonial times, as early as the 16th century,- whereas others were not discovered until the 19th and 20th centuries. The extraordinary gold-silver potential of this young volcanic complex, however, was not recognized until the 1970's when the phenomenal increase in gold and silver prices stimulated new exploration. New discoveries were made, chiefly in southern Peru and northern Chile, of high-grade ores in old mining districts and large low-grade ore bodies, both in old districts and in new areas having no history of mining activity. Many additional gold and silver deposits remain to be discovered within and beneath the young volcanic complex of this region.

Jan 1, 1990

By J G. Webster-Brown, K L. Brown

The Waihi Region is host to many low sulphidation epithermal Au-Ag deposits. The Golden Cross mine located at the head of the Waitekauri River, eight kilometres NW of Waihi, was a gold mining operation that placed significant emphasis on environmental management. An assessment of the influence of this mining project on stream sediment geochemistry (Fe, Mn, As, Cu, Pb, Zn, Cr, Cd, Ni, Ag and Se) in the Waitekauri Catchment has been made. Effective waste management during the mine operation appears to have prevented contamination of stream sediment. Trace metal concentrations in the Waitekauri Catchment sediment have generally decreased since 1987, and are currently mainly below the ANZECC (2000) sediment quality guidelines. However, elevated As levels were recorded in the Upper Waitekauri River and Battery Stream, exceeding guideline values. Elevated levels of Cu, Pb, Zn and Cd were found in the Huanui Stream, a tributary of the lower Waitekauri River. This reflects the influence of past mining operations in the valley, as well as natural weathering of hydrothermally altered Coromandel Group andesite. At a number of sites, Mn concentrations also exceeded sediment quality guidelines, and this may be derived from the remediated Golden Cross mine site.

Jan 1, 2003

The addition of a thallous salt to the cyanide leach of a calcined pyritic concentrate causes a marked increase in the"rate of extraction of gold. This probably is due to the activation of passive gold by.th,e. thallous ions'.''Lea'd, bismuth, and mercury salts, which should produce ' a, similai effect, fail to do so. It is postulated that'this latter result, together with'the reprecipitation of silver at low cyanide levels, is due to the presence of soluble sulphide. The use of thallous salts to reduce leaching time is discussed briefly.

Jan 1, 1964

By S L. Simpson, J Waworuntu, B M. Angel

"The Batu Hijau copper/gold mine, operated by PT Newmont Nusa Tenggara, is located in the south-western part of Sumbawa Island, Indonesia, and is situated ~10 km from the south coast at an altitude of ~450 m above sea level. The mine became fully operational by year 2000 and processes approximately 120 000 t of ore per day that contain an average of 0.53 per cent copper and 0.4 per tonne (g/t) gold. Tailings management at the mine includes a deep-sea tailings placement (DSTP) system that discharges tailings through a pipeline via an outfall located at a depth of 125 m at the head of the submarine Senunu Canyon (Figure 1).The environmental impact assessment undertaken prior to approval of the DSTP evaluated both on-land tailings storage facility (TSF) and DSTP options for tailings management. Negative attributes of the on-land TSF included removal of approximately 2300 ha of forest/agricultural land, the potential relocation of >2000 people from their communities, the high average annual rainfall (>2500 mm) and potential for earthquakes presenting challenges for water management and creating a long-term risk of failure. The final choice and Indonesian Government’s approval of DSTP was also influenced by the close proximity of the deep submarine canyon to the mine. The Batu Hijau mine is one of the larger examples of DSTP in the world and deposits tailings at the greatest depth. The depth of the main canyon increases to >2000 m within 20 km of the coast, and to >3000 m approximately 50 km from the coast.The DTSP at Batu Hijau must comply with an environment management plan (EMP) and environment monitoring plan of permit stipulation that approved its commencement in 2000; updated in 2010 and 2015. The environmental management objectives were to avoid impacts to highly productive components of the ecosystem such as coral reefs, mangroves, surface waters and fisheries, and confinement of impacts to areas of low biological productivity. In the vicinity of the DSTP outfall and within the Senunu Canyon, the management plan predicted significant adverse impacts from the DSTP on the marine ecosystem in the form of: reduction in sea water quality due to elevated turbidity and dissolved copper concentrations burial of benthic organisms a reduced habitat for demersal fish.Recovery of the pelagic and benthic ecosystem to preoperating conditions was predicted to occur within the first two years after operations cease. The CSIRO has performed due diligence studies to independently verify compliance with permits and evaluate new monitoring objectives (Apte et al, 2004; Simpson et al, 2010; Angel et al, 2015), and has performed assessments of environmental monitoring data on the tailings footprint and ore stockpile processing against the above environmental objectives (Simpson and Angel, 2015).CITATION:Angel, B M, Simpson, S L and Waworuntu, J, 2016. Long-term monitoring and targeted assessments to improve management of mine wastes – the Batu Hijau project, in Proceedings Life-of-Mine 2016 Conference, pp 81–84 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Jun 28, 2016

By Weller KR

Computer programs are described which help the metallurgist to process sample data from a plant survey; to carry out simple mass balance calculations; to present the results of circuit and equipment performance in convenient form; and to simulate the circuit response to changing operating conditions. The uses and limitations of these programs are explained by following through a case study of the sulphide flotation circuit at Cleveland Tin Ltd. The circuit was sampled, the data analysed, and some process inefficiencies established. Simulation calculations were then made to provide information on which to base decisions regarding possible circuit changes aimed at improving performance.

Jan 1, 1983

By Ramsay WRH

The Mount Stavely Volcanic Complex compri- ses one of a number of northerly trending fault bounded greenstone occurrences in Western Vict- oria, of probable Cambrian or older age. The greenstone belt is coincident with several linear positive aeromagnetic anomalies, which outline the surface and subsurface extensions of these greenstones. Mapping at Mount Stavely has identified serpentinite, variolitic basalt, two-pyroxene and pyroxene-hornblende andesite, dacite, rhyodacite and their pyroclastic equiv- alents. Chemically and mineralogically the volcanics constitute a calc-alkaline assemblage. The mineral potential of the region has been enhanced following a discovery by Pennzoil of Australia Limited near Ararat, of sulphide min- eralisation containing approximately 1 million tonnes at 2.7 percent copper. The volcanic environment of the Mount Stavely Volcanic Complex is discussed in terms of similar environments found in Canada.

Jan 1, 1982

By Nekitel S, Arumba J, Kopi G, Findlay RH

The Kainantu area lies within the composite Scrapland terrane which is composed of Mesozoic metamorphic and intrusive units, overlain by Cenozoic marine sediments, volcanic and intrus-ive units and Quaternary fluvial sedi-ments.Four deformations (Dl, D2, D3, D4) are recognised within the Mesozoic sequences, which consist of greenschist to amphibolite facies schist derived from felsic to intermediate pyroclastic rocks and pelitic sediments. The second, third and fourth fold events are present in the Cenozoic sequence, and these rocks are broken by thrusts related to northwest trending D3 folds. South-dipping, possibly lystric, normal faults are recognised and may be related to uplift and exposure of the metamorphic rocks as core complexes.Known mineralisation in the area consists of gold and copper skarn deposits, porphyry copper deposits, shear-hosted gold deposits, epithermal vein deposits and gold placer deposits. Over 35 hard rock and 18 gold placer deposits are known within the area. Of significance are the Kathnell shear-hosted auriferous quartz veins; such structurally controlled veins may be more widespread than proposed prev-iously and offer a new exploration target.

Jan 1, 1994

By Chapman J, Kanchibolta S. S Poetschka N L

A field study was undertaken at Marandoo iron ore operations to investigate the effect of blasting on the lump/fines ratio. Three blasts, each in a different ore domain were monitored and the blasted ore was subsequently audited through the tr

Jan 1, 1998

By Williams P

The assumptions made in conventional (Terzaghi) consolidation theory are not met in a tailings deposit. Finite or large strain consolidation theory must be employed. The paper describes such a consolidation model and its application to the design of tailings impoundments, water management systems, and long term rehabilitation.

Jan 1, 1990

The Mesozoic intrusive rocks in southeastern coastal China can be divided into three intrusive suites, and they can be brought into corresponding with four cycles of volcanic activity. This paper describes their time-space relation with volcanic rocks, and their geochemical characteristics. Data from the Mesozoic volcanic-intrusive. complex rocks in Eastern Zheijiang, Eastern Fujiang and Eastern Guangdong show distinct regional differences, both within and tectonomagmatic activity regions. The southeastern coast of China involves four tectonomagmatic activity regions. They have many differences on the nature of magma source regions, activity patterns of magma, time-space distribution, petrography and petrographic facies association of volcanic and intrusive rock and mineralization.

Jan 1, 1990

By Hoberg H, Schnieder FU

The disposal of residues from coal preparation and processing will to an increasing extent require investigation and consideration of the environmental problems resulting as a consequence of this. Different authors (Diingelhoff and Plankert, 1983; Hasenpatt, 1985; Szczepanska and Twardowska, 1987) have concentrated primarily on the content and the mobilisation of inorganic contaminants such as chlorides, metals and heavy metals from spoil tips, while no publications have yet been found on the question of a possible emission of organic contaminants (PCB, PAH, HC HC) from processing residues. Here the flotation residues in particular are able to bind larger quantities of organic contaminants by physi-sorptive means because of their large specific surface and, after disposal, to be re-emitt than into the environment. The flotation agents used in coal flotation are mixtures of technical distillation products with a correspondingly fluctuating composition. As Hey, 1986 showed, they may contain, in addition to the main components (n-alkanes, alcohols, surfactants), over 50 individual trace substances. In conjunction with the structural-chemical similarity of the individual components, this complicates the quantitative analysis of individual components considerably. For the analysis of hydrocarbon content of flotation products by means of extraction with organic solvents in accordance with DIN 38408, H18, the difficulty arises, besides the insufficient sensitivity at low concentrations, that geogeonic hydrocarbons are extracted from the coal as. well and the analysis results are thus falsified. These problems were overcome by the application of the 14C radiotracer method where certain components of the flotation agents are marked with radioactive carbon (14C). By measurement of the radioactivity of solid and liquid samples, the concentration of the marked substance can be measured very sensitively and precisely, whereby the accumulative measurement of similar organic substances is ruled out. Thus the reaction path of certain substances in complex reagent mixtures such as flotation agents can be traced excellently and the conceivable environment burden resulting from flotation tailings disposal can be estimated. In this paper, the adsorption behaviour of typical components of coal flotation agents are investigated for different coals and types of gangue material, the reagent content of flotation concentrates and tailings, as well as the mobility of the reagents adsorbed onto solids. The knowledge of adsorption and desorption mechanisms of unpolar hydrocarbons emulsified in water to solids are also of particular interest for the understanding of processes of organic soil contamination and for the further development of washing processes for oil-contaminated soils.

Jan 1, 1993

The Role of Mineral Processing in the Development of Cement with Low Carbon Emissions

Sep 13, 2010