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By K L. Temel, W P. Player

The underlying message of this paper is that investment in prospecting, exploration and mining in New Zealand is welcomed. The Government's policy with respect to Crown owned minerals is for continuing investment in prospecting, exploration and mining which is in accordance with good exploration or mining practice. To encourage continued investment requires a business-friendly environment. Government policies and initiatives to enhance the business environment for the minerals and coal exploration and mining industries are discussed in this paper. As well, new initiatives under consideration, which have the purpose of enhancing the investment environment, are discussed.

Jan 1, 1997

Simulation and Analysis of Media Behaviour in the Tower Mill by Discrete Element Method for Estimating the Power Draw and Spatial Distribution of Grinding Process The trends to the Tower Mill (TM) for grinding the materials are increased recently due to its unique merits. Among the various considerations of this machine, the main important items are increasing the efficiency of grinding as more as possible while keep the power consumption, manufacturing and maintenance costs as less as possible. Because this grinding process includes a huge numbers of media particles (ball or other shapes) that are interacted with each other and body of the machine, the DEM (Discrete Element Method) way is a very useful and essential step to getting confident evaluations. Because the DEM simulation is a very young scientific field and proper commercial software are very rare and still under modification, at first step, a FORTRAN code is developed for DEM simulation of two laboratory Tower Mill models (KM5 and KD5). The simulation and experimental results matched each other properly. Then one another DEM software was implemented to perform simulation of bigger models (huge numbers of balls), meanwhile could handle the complex 3D geometry data. The simulation and experimental results were compared and analysed in detail for not only laboratory but also for industrial models (KW5, KWD5, KWD50, KW300F, KW700F and KW1500) without any manipulation or compromising of the parameters of simulation. Some numeric data of industrial models are hidden here due to confidential reasons. The relative velocity of balls (ball-ball and ball-TM body), dissipate energy, interacted forces and stresses during the process are the key outputs of DEM simulation for design this machine. Therefore the main important processes in a Tower Mill machine are recognised and consequently some horizons of development of this machine are distinguished.

Sep 13, 2010

By Holdgate G. R, Thompson B. R, Webster R. L, Bolger P. F

The Gippsland Basin in south-eastern Australia has an area of approximately 46 000 sq km. It is one of the world's major coal and petroleum bearing basins, with most of the former occurring in the smaller one fifth on-shore part. The stratigraphy, structure and economic resources of the Tertiary sedimentary pile is now well known through extensive drilling for coal and petroleum. In contrast, the older Cretaceous sequences through their lesser economic importance are relatively less explored. The sedimentational history of the Gippsland Basin has largely followed along similar lines of development to the many other southern Australian basins since the Cretaceous break-up of Gondwanaland. However, the scale of accumulation of coal and hydrocarbon source rocks is unprecedented and differentiates this basin, for reasons less well understood, from the others. Large scale open cut brown coal mining since the late-1920s has been carried out in the western extremities of the basin, while vigorous extraction of some two thirds of Australian petroleum products taken place in the offshore part. Brown coal seam thicknesses and economically winnable reserves are huge and outrank most other brown coal basins of the world. Development of the resource currently meets the need for electricity generation throughout the State of Victoria, but other future developments such as conversion to oil, being investigated.

Jan 1, 1992

By Miezitis Y

A weak airborne radiometric anomaly was examined in the field and the presence of uranium confirmed. Rotary-percussion drilling showed the presence of uranium but a subsequent programme of diamond and rotary percussion drilling indicated that the concentration of uranium was uneconomic. Within the tufts and volcanics of the prospect the uranium existed as uranyl phosphates within the oxidized zone. Geological mapping and the diamond drill core showed that the Stag Creek Volcanics are part of the Lower Proterozoic Masson Formation, probably with member status, rather than the expression of an Archaean basement ridge. This change in the interpretation of the fundamental structure of the Pine Creek Geosyncline has led to a reexamination of the stratigraphy and to suggestions which differ from the current concept.

Jan 1, 1977

The authors describe two stratiform intrusions within a two miles thick ophiolite belt, one of the many ophiolite (serpentine) belts of the eugeosynclinal sequences of the Kalgoorlie System (metamorphic age c.2700 million years). Unusually good evidence of gravitational differentiation involving cumulates for an Alpine type peridotite-gabbro intrusion has been obtained, in spite of modifications of the original igneous rocks imposed by regional metamorphism. Unmetamorphosed relics of cumulate rocks are a surprising feature of this occurIfence.'fhe differentiation process reflected in the layered sequences is compared to that of the Stillwater Intrusion, Montana. Phase, cryptic and rhythmic layering are recognized. The economic significance of this study lies not only in the possibility of nickel mineralization in this ophiolite belt, but also in that much detailed information on the nature of these belts, which is difficult to obtain in the case of the more altered and sheared rocks of the belts carrying gold and nickel ore deposits nearby, is gathered from the Yilmia occurrences.

Jan 1, 1969

The Metallurgical Development of an Enargite-Bearing Deposit

Sep 13, 2010

By M Boyd

The University of Wollongong was named University of the Year 2000, for its work in preparing students for the e-world. Computer facilitated learning is being introduced into subjects throughout the engineering course. First year mining engineering students are introduced to computers, e-communication, using the UniversityÆs web based information system, and web based subject delivery. Mining engineering students in the mid-years of the course use programming languages and numerical computation software such as MATLAB, while students in the final years use a range of commercially available professional engineering software such as TALPAC. Most of these subjects are offered as part of the UniversityÆs Learning Online program, co-ordinated by its Centre for Educational Development and Interactive Resources (CEDIR). Learning Online subjects are delivered using the Web Course Tools (WebCT) environment. WebCT allows all resources to be accessed through the web, allows email communication between lecturer and student, and allows discussion groups for the exchange of ideas. Students can submit their assignments through WebCT and receive immediate feedback. This paper describes how WebCT has been used to deliver a first year engineering computing subject, mid-year numerical computation subjects, a mining economics subject and mine planning subjects.

Jan 1, 2002

Precision surface mining is increasingly occupying a significant role in open pit mining. Improvements in technology now allow continuous surface mining of material well above 140 MPa (20 300 psi) efficiently and cost effectively when compared to drilling and blasting/primary crushing methods. These include the elimination of the use explosives and primary crushing, the ability to precisely extract the ore from the waste, or separate ores of varying chemistry and mine thin seams and non-homogenous orebodies cost effectively. In addition, precision surface mining extends the useful life of a mine by extending the mine boundaries. It can expand production capacity in existing mines and is particularly cost effective in greenfield start-up mines. Precision mining techniques result in higher percentage recoveries. This paper reviews several of these techniques for the Terrain Leveler« surface excavation machine (SEM), and shows their impact. Vermeer's current approach to precision surface mining is utilisation of the T1255 Terrain Leveler SEM. Several units have been proven in round-the-clock, seven day operations throughout the world. Among other innovations are design simplicity, stability, maneuverability, rear-mounted tilting drum and top-down cutting. The impact of these items are discussed in more detail in the paper. After a detailed analysis of the importance of machine availability on overall mine performance, Vermeer has extended its equipment line to include a direct-drive option for its T1255 Terrain Leveler SEM. In addition, improvements in dust suppression are presented. While the T1255 Terrain Leveler SEM is of optimum size and cost in small and medium sized mines, Vermeer has recognised that larger mines require larger machines with increased capacities. Vermeer will prototype the T1655 Terrain Leveler SEM later this year. Specifications of this machine and up-to-date preliminary results are presented. A discussion of the role of each machine size and driving mechanisms are included. Finally, the next stage in Vermeer's providing solutions to the surface mining community will be described - a continuous loader. The impact on current mine planning is presented using a detailed computer program developed for studying the impact of loading techniques and higher production rates on mine plan optimisation.

Dec 6, 2010

THE following brief paper is submitted with a view to encouraging the exploitation of hitherto neglected 10w~ grade ore-bodies which are suitable for extraction by open-cut methods.The Corinthian North mine, situated 10 miles from Southern Cross, in the Yilgarn district of Western Australia, furnishes an example of low working costs, although operations are carried out on quite a limited scale.The body of quartz which is now being worked strikes N.W. and S.E., has a very slight underlie to the west, and lies between bodies of quartz-hrematite s,chist on the east and amphibolite on the west.So far as the property has been explored, it would appear that the underlying sulphide rises to within about 70 ft. of the surface in the northern end of the workings, and pitches away to the south at a grade...

Jan 1, 1915

OWING to two large falls of ground which resulted in serious accidents occurring towards the end of 1908, it became evident that the "open chamber" system then in use was unsuitable for the conditions existing in the Mount lVIorgan mine. It will be admitted that in all mining operation, the first consideration is the economy of the system adopted, combined with its safety and ability to give the desired output. A sectional system with square sets has been introduced into the mine, in which due attention has been paid to these factors. In this paper a brief description of this system will be given. An outline of those previously used will be ineluded, as it is necessary to understand the eonditions which existed in the mine at the initiation of the sectional system. Outside the actual mining methods employed, various points that might prove of interest will be touched on.The square set system of mining has been in use throughout the stopes in the gold ore in the upper levels of the mine since underground operations were started in Mount Morgan.

Jan 1, 1910

By C De-Vitry

"The large Yandi channel iron deposit (CID) is located in the north-west of Western Australia and is currently mined via open pit methods. Drilling at Yandi is widely spaced and current estimates are mostly linear averages of the surrounding local samples. Linear estimates such as ordinary kriging (OK) based on block sizes that are significantly smaller than the dimensions of the drilling grid are less variable than the unknown reality (Armstrong and Champigny, 1989).Conditional simulation (CS) provides a series of plausible realisations that represent the actual grade variability at a small scale (eg 1 m + 1 m + 1 m). These simulations are very useful for a number of purposes, eg: optimising grade control, stockpiling and blending selection of optimal drill hole spacing assessing resource risk on contained tonnage and metal.At Yandi the major constituents of the ore (Fe, P2O5, SiO2, Al2O3 and LOI) are correlated to varying degrees. Independent CS of each assay variable will not reproduce these correlations. Reproducing the correlations (and the shape of scatterplots) is important if the simulations are used for the abovementioned purposes. This paper examines and compares various methods of CS that aim to reproduce the correlations between the assay variables.The CS methods evaluated in this paper are conditional co-simulation (CCS) using the linear model of co-regionalisation and two other, alternative multivariate simulation methods, which use min/max autocorrelation factors (MAF) or the stepwise conditional transform (SCT) to de-correlate assay variables before performing independent CS. It was found that CCS best reproduced the characteristics (histograms, variogram, scatterplots, etc) of the declustered drill hole data (Figure 1). Whilst simulation using MAF generally produced acceptable results, the method did not adequately reproduce the variance of the assay variables. The univariate statistics, histograms and experimental variograms were acceptable for simulations generated from the SCT. Bivariate statistics, cross-variograms and scatterplot reproduction for the SCT were unacceptable. The latter method produced inferior results because there were insufficient samples to obtain a reliable transform of the third assay variable in the transformation sequence.None of the abovementioned simulation methods provides good reproduction of all the scatterplots. This is due to the presence of clay pods, which cause some scatterplots to display two trends. These clay pods contain higher percentages of SiO2 and Al2O3 than the surrounding CID. The clay pods are generally smaller than the drill-grid dimensions. Thus their locations are typically unknown and they cannot be defined by manual interpretation, eg via wireframes. The locations of the clay pods were simulated via indicator CS. CCS was then performed separately for the clay pods and the CID. This significantly improved the reproduction of the correlation coefficients, the scatterplots and visually the simulation was more geologically realistic. Simulating the location of clay pods followed by CCS of assay variables is the recommended approach for simulation at the Yandi CID.CITATION:De-Vitry, C, 2013. Simulation of correlated assay variables - a case study from the Yandi Channel iron deposit, in Proceedings Iron Ore 2013, pp 137-148 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Aug 12, 2013

Uranium exploration over a wide area of the Southern Frame Embayment, South Australia, has defined a number of Lower Tertiary fluvial palaeochannels incised in older rocks. The buried channels contain similar stratigraphicsequences of interbedded sand, silt, and clay, probably derived from the adjacent uranium-rich Olarv Provinee. Uranium mineralization is pervasive within two major palaeochannels, and four small uranium deposits have been found in the basal sands of these channel sequences, at the margins of extensive tongues of limonitic sand.One of the channels is examined in detail with respect to channel morphology, stratigraphy, and rock alteration and the geology and ore controls of the contained uranium deposits are described.A geochemical zonation reflected by variation in limonite, pyrite, carbon, and humic malleI' is defined across one of the deposits. A genetic model is proposed suggesting formation by a uraniferous geochemical cell which migrated down the stream gradient and concentrated uranium on its lateral margins adjacent to the channel bank.

Jan 1, 1978

Undisturbed minor sedimentary structures-cross-bedding, ripplemarking, scour-and-fill, slumping-are present in most of the rock types in the Willyama Series of the Broken Hill district and in the orebodies.This indicates that there has not been any significant movement of mineral matter within or into the rocks during or after metamorphism, that the rocks have not flowed during tectonic deformation or during metamorphism, and that the ore is an original sedimentary deposit in its sedimentary position.Sedimentary processes, depositional and mechanical, are indicated to explain the deposition of sedimentary metallic minerals and their concentration into large masses. The Broken Hill orebodies show evidence of these processes.INTRODUCTIONI visited Broken Hill for one week in May, 1958, at the invitation of Mr. Haddon F. King, Director of Consolidated Zinc Pty. Ltd. He asked me to examine the rocks and orebodies in the mines and outcrops at Broken Hill for:1. Sedimentary structures that might be used to determine the facing of the banding;2. Indications of the original nature of the rocks if I considered they may have been sedimentary; and3. Indications of any possible sedimentary origin for the ores.It has been stated (Gustafson et al., 1952, p. 30) that there was no indication, in the banding, of the facing of the banding, but recently B. P. Thomson had found examples of what he had interpreted as graded bedding (personal...

Jan 1, 1959

The mineralogy and microstructure of mattes from the nickel flash smelter at Kalgoorlie, Western Australia, have been studied. The flash furnace matte consisted mainly of an intimate mixture of pentlandite and heazlewoodite with some nickel metal. The electric furnace matte was mainly an iron-nickel alloy with subsidiary pentlandite while the converter matte consisted mainly of heazlewoodite with crystals of nickel metal.

Jan 1, 1977

In redesigning the cyanide plant at Mount Torrens, in conjunction with Mr. L. W. Grayson, the manager, several minor alterations were introduced in order to have the operations under thorough control, and these having proved serviceable may be of sufficient interest to merit a description here. The lixiviation vats, though only 8 feet in diameter, were retained, but the pipes leading away from the bottom were reduced from two inches to half-an-inch in diameter, and had a fall to the zinc boxes of about 4 feet. As these small pipes were completely filled by the solutions fiowing away from the vats, they exerted a suction equal to their fall and thus hastened the rate of flow, so that tailings containing a larger proportion of slimes could be treated than was possible where the larger pipes were used, as, there not being sufficient fiow of solution to keep the latter filled, no suction could be obtained with them. It was found that with'most of the tailings treated a sufficient flow could be obtained from the half-inch pipes when the taps on, them were only one-third to half open. The lower end of each of these pipes was connected by means on indiarubber tubing with the sille hole of 11 in aspirator bottle, and to the mouth of this bottle a few feet of similar tubing was connected, so that the solutions coming through could be directed into either of the fixed tubes leading respectively to the waste water tank the strong solution zinc boxes or the weak solution zinc boxes.In working the vats, the following method was found to give good results. While filling the vats with tailings the taps were left open, so that the water might drain off into the waste water tank the surface of the tailings was carefully levelled. When the strong solution was run in at the top, the air contained in the interstices of the tailings was forced through the half-inch pipe at the bottom as a strong blast, instead of, as I believe js usual, escaping by means of channels formed by it through the tailings, and thus tending, it would appeal, to render the disposition of the tailings less even and to make.

By S Yuen, T Rana, S Khan

Many open pit mines require dewatering or need aquifer depressurisation systems to manage mine water inflow and/or mine floor stability. In many instances these mining operations impact on regional groundwater resources and therefore access to these resources by other users.As such potential exists for mine development to be hindered or even blocked by groundwater legislation that aims to prevent declining groundwater levels and demonstrate equitable use of a regional groundwater resource.There is a need to manage aquifer systems during and after the mining operations, and in some cases stresses on the aquifers and associated ecosystems may be elastic and can be managed with minimum impacts or reversed once the mine ceases to operate.This paper uses the Gippsland sedimentary basin, with a history of declining groundwater levels and mining and petroleum production, as a case study to pose the question: Should period of mining operation, aquiferÆs storage capacity and its ability to recharge be concurrently considered when granting groundwater abstraction and mining licenses for prospective mine development?It further examines that by utilising an aquiferÆs storage capacity and demonstrating an understanding of aquifer system hydrodynamics during and beyond the life of the mine (time), the approval process for groundwater abstraction and associated cost of statutory monitoring may be made less onerous.

Jan 1, 2009

By Armstrong M

The Coal Mining Engineering Branch of the New South Wales (NSW) Department of Mineral Resources, in its continuing effort to improve coal recovery from underground coal mining operations, has undertaken a study of the mechanics of sub-surface deformation caused by caving of the extracted area behind retreating longwall faces. The strata movement was monitored by a multi-wire borehole instrumentation system consisting of mechanical anchors installed at different horizons in a borehole extending from the surface to the coal seam. The mechanical anchors were connected to the suspended weights on the surface by stainless steel multi-strand wires. The movement of these weights was monitored as the longwall face approached and retreated past the borehole. The anchors started subsiding as soon as the face retreated past the borehole and continued to subside until the subsidence levelled off when the face retreated 900 m past the borehole. The zone of major caving and bed separation extended to roughly 10 to 13 times the extracted seam thickness and high tensile strains developed inthis zone. The bulking factor of broken strata was less than 1.14 which indicated that the roof layers collapsed in big blocks. The goaf compaction was almost complete when the face retreat was 200 m. Low tensile strains prevailed in the strata overlying the zone of caving and bed separation.

Jan 1, 1986

By Paterson R. G, Compston W

The Mine granite at the Ardlethan tinfield is dated by Rb-Sr on a muscovite concentrate at not less than 417 ± 2.5 Ma (2s), consistent with the intrusion of this granitic body into folded Late Ordovician sediments. A combination of Rb-Sr and K-Ar evidence suggests a slightly younger age, 41O ± 2.5 Ma, both for the neighbouring Ardlethan Granite and for the hydrothermal alteration of the Mine granite, with which the tin is associated.On this basis, the somewhat high 206Pb/204Pb of two galena samples from within the hydrothermal alteration zone is best explained by an increase in U/Pb of order 10 per cent during a geochemical event in the Late Precambrian, in the rocks which eventually yielded the Pb to the mineralising fluid. This earlier event probably increased Th/U in these rocks as well, by as much as 5 per cent. If these reconstructions are valid, the lower-than-average U/Pb implied for the original Precambrian source rock bespeaks a mantle component of marginally greater proportion than for "average orogene".

Jan 1, 1982

By R Byrnes, P Hensley

The outstanding environmental management initiatives undertaken by Novacoal at its Western Main Site near Lithgow in New South Wales over the past five years are detailed in this paper. These initiatives have been based on a combination of proven and innovative investigation and implementation techniques, close consultation with regulatory authorities and full support by colliery management. The results of these initiatives have enabled the colliery to exceed its pollution control obligations from a base well below industry standards. The initial poor condition of the mine was the result of over 50 years of traditional mining which paid little regard to environmental management. The transformation of the colliery within such a short period, with limited capital, is considered a model for the N.S.W. coal industry.

Jan 1, 1995

By Rayner B

Five wells have been drilled in the Basker/Manta Block of VIC/P19, Gippsland Basin, resulting in sub-economic Intra-Latrobe Group oil and gas discoveries at Basker-1 and Manta-1. A total of 21 individual hydrocarbon bearing sandstones were intersected by the two wells. These reservoir sand bodies were deposited by fluvial processes in a lower coastal plain environment. The modelling of sand body orientation and geometry is a critical component in the evaluation of the two accumulations. Seismic resolution of the thin (average 2 m to 5 m) sand bodies is inadequate for mapping their orientation and distribution. Dipmeter data has been successfully applied to the problem of orienting the sand bodies using FMS images acquired during the drilling of Gummy-1 and reprocessed HDT data from Basker-1 and Manta-1. Prediction of lateral extensiveness (geometry) of individual sand bodies has also been attempted. Interpreted palaeocurrent direction from all three wells is dominantly from the NW to the SE. Reservoirs in the Manta-1/Gummy-1 area are interpreted to be predominantly channel sands, deposited by relatively low sinuosity streams. As such they would tend to have a laterally extensive, elongate geometry. Sand bodies deposited in the Basker-1 area show a predominance of laterally accreted cycles deposited by meandering streams. Channel geometry may then be limited in the downstream/upstream direction by internal permeability barriers such as clay plugs.

Jan 1, 1992