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By Y Miyoshi, J Ishibashi

"An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation. Sea floor hydrothermal activity in the Okinawa Trough is considered a modern analog to ancient Kuroko-type volcanogenic massive sulfide (VMS) deposits. Recent scientific drilling projects at active hydrothermal fields have enabled us to conduct comparative studies on hydrothermal clay minerals between ancient and modern systems. Zonal distributions of clay minerals below the sea floor of an active hydrothermal field have been revealed, which is represented by the distinctive assemblage of clay minerals. Zone 1 consists mainly of montmorillonite and sometimes of kaolinite; Zone 2 consists of chlorite and chlorite-smectite mixed-layer mineral; and Zone 3 is represented by the co-occurrence of illite and chlorite, from shallow to deep. This zonal distribution is likely to be in accordance with that reported previously for the Kuroko-type ore deposit. Similarities are also recognised in chemical compositions of illite and chlorite, which are both abundant clay minerals in the vicinity of the ore deposit. While illite would be formed by interaction with the hydrothermal ore fluid, the formation of Mg-rich chlorite is attributed to Mg metasomatism caused by the involvement of sea water. Further studies, especially focusing on interactions between fluid and solid phases, would significantly promote our understanding of dynamic processes for the formation of VMS depositsCITATION:Ishibashi, J and Miyoshi, Y, 2015. Hydrothermal alteration process in active sea floor hydrothermal systems in the Okinawa trough, from a viewpoint of a modern analogue for the Kuroko-type volcanogenic massive sulfide deposits , in Proceedings PACRIM 2015 Congress, pp 481–486 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 18, 2015

Analysis of Electrostatic Separation for Rutile Cleaning Duty Using a Plate Electrode Assisted High Tension Roll Separator A plate assisted electrostatic high tension roll separator has been used for the removal of impurity mineral grains from a rutile rich product stream. A laboratory study and a subsequent production study explored the effect of machine conditions with a view to the optimisation of the separation performance of the separator. The performance requirement was that the TiO2 grade in the non-conductor stream was to be less than ten per cent whilst at the same time the ZrO2 grade in the conductor stream had to be less than 0.5 per cent at mass recoveries of greater than 90 per cent to the conductor stream and less than 5 per cent to the non-conductor stream. Mineralogy data was utilized to determine the feasibility of achieving the production targets with the feed under study. Since the feed stream mineralogy was dominated by rutile, leucoxene and zircon, it was possible to use an approximation to the actual mineral assemblage as well as the raw X-ray fluorescence data to understand the separation duty of the Carrara machine. Since there were four conflicting criteria used for the performance requirement, an index was devised that incorporated all the requirements simultaneously. This new index was the sum of the squares of the difference between the achieved and desired values, weighted with respect to the variance of each variable. If the desired value for a particular criterion had been met its contribution to the sum was set to zero, no matter how well the criterion had been met. For the production machine the strict requirements were almost achieved. As expected, the achievement of the target performance was dependent of the feed conditions at the time of measurement. This paper reports the results of this study.

Sep 13, 2010

By T M. El Hajj, A C. Chieregati, M T. G C Marques, J M. Braga Jr, H Delboni Jr

"The estimate and control of sampling errors is essential for all mining operations, especially when dealing with strategic materials, such as niobium. This paper is based on a traditional quality assurance and quality control technique used to confirm mineralised intersection zones, and proposes the validation of sampling data using diamond drill twin holes, in order to evaluate and improve the quality of the current data set. The geological model of the niobium mine – located in Araxá, Minas Gerais, Brazil – was built including 77 diamond drill holes of a sampling campaign carried out during the 1970s. There are few records about the collection and preparation procedures of these past samples, making it difficult to estimate the errors associated with their analytical results. Therefore, 11 twin drill holes were drilled to compare their samples against the samples from the 1970s drilling campaign. The new hole locations were chosen as near as possible to the old holes location. The JORC Code, 2012 edition, relates the use of twin holes as a good sampling technique to assess sampling and assay data. Three parameters were considered to validate the 1970s drill hole campaign by the twin drill hole campaign: the difference of the coordinates between the paired holes the difference among the positions of the geological contacts to validate the geologic description the difference between the paired samples grades was calculated to validate the analytical results.The analysis of the grade range variation between sample pairs was based on three techniques: geostatistical interpretation of vertical semivariogram to obtain the nugget effect calculation of the relative difference between duplicates calculation of the error associated with the sampling protocol established according to Pierre Gy’s Theory of Sampling.The results were satisfactory for hole coordinates; however, the ore content showed a high deviation, although this divergence can be explained by the nugget effect. For the lithological intervals, the new results contributed to an effective identification of variations among lithologies, ie brown weathered ore and saprolite. The twin drill holes campaign successfully validated the geological model data, allowing effective mine planning and higher reliability of the reconciliation results.CITATION:Marques, M T G C, El Hajj, T M, Braga Jr, J M, Chieregati, A C and Delboni Jr, H, 2017. Theory of Sampling and geostatistics for twin drill holes analysis in a niobium mine in Araxá, Brazil, Australia, in Proceedings Eighth World Conference on Sampling and Blending, pp 97–106 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

May 9, 2017

By S Hapugoda, A Poliakov, E Donskoi, L Lu

A significant amount of metallic iron in the world is produced in blast furnaces from iron ore pellets. To control the quality of pellets and to optimise pellet production, characterisation of both green and fired pellets is required. Optical image analysis (OIA) allows identification of different minerals, binder, remaining fluxes and porosity within pellets.For proper identification of the mineralogy, porosity and texture in pellets a high magnification is required, therefore each individual image covers only a very small portion of the pellet. At the same time the characterisation of pellets requires that the whole pellet is represented as a single object, so the size of the resulting overall image at high magnification can make it difficult to handle. A solution to this problem has been implemented within the CSIRO OIA package Mineral4 by combining images at different levels. Namely, to average out local irregularities, individual frames can be stitched during imaging into larger MosaiX images. Mineral4 further combines these MosaiX images into a single panorama image of the whole pellet.The proposed procedures allow the calculation of mineral and porosity spatial distributions, local gradients and abundance graphs based on the distance from the centre of the pellet. The ‘Pellets’ module of CSIRO OIA software also allows for characterisation of large irregularly shaped particles of lump ore and sinter.CITATION:Poliakov, A, Donskoi, E, Hapugoda, S and Lu, L, 2017. Optical image analysis of iron ore pellets and lumps using CSIRO software Mineral/Recognition, in Proceedings Iron Ore 2017, pp 583–592 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

Orebodies are defined in economic terms in that they must satisfy conditions determined by costs of mining, extraction and marketing before being so described. Despite this they have an essential chemical character as specialized products resulting from geochemical differentiation, and it is surprising that so little basic geochemical research has been carried out with respect to ore occurrence and that prospecting methods based on geochemical principles are not more widely applied.Many exploration geologists associate geochemistry with analytical techniques applied to the detection of dispersed traces of metals from actual orebodies. Geochemical research, applied to economic geology, goes far beyond this limited field and the purpose of this paper is to discuss aspects of such research and its use in formulating exploration principles.THE GEOCHEMICAL BACKGROUND TO MINERAL OCCURRENCE AND EXPLORATIONThe three aspects of economic mineral deposits to which geochemical research can be of use in determining ore guides are genesis, control of deposition and mode of dispersion from orebodies after emplacement. Prospecting for mineral deposits is primarily based on theories of ore occurrence which deal with the genetic and depositional influences controlling localization of ore. There are many such theories and they will not be discussed here as they have been adequately reviewed in geological publications. Some are based on differing argument concerning the same empirically observed associations of ore. In this respect it is perhaps fortunate that they are not always mutually exclusive as regards the...

Jan 1, 1960

The key to the successful debt funding of a new mining project, whether in economically established or developing nations, is the submission of a comprehensive feasibility study. The feasibility study forms the basis from which the resource banker can construct financial models which govern the amount of available funds, the conditions which control the supply of such funds and the time period over which the loan may be repaid. The bank will wish to ensure that the feasibility study is the best representation and confirmation of reality possible because this model is the basis of the loan security package. Thus the study will be vigorously interrogated by independent experts in all its elements including the ore reserve, mineability, metallurgy, operating and capital cost profile, environmental factors and management. A well constructed feasibility study, undertaken by well recognised and respected independent consultants can save the client company a great deal of real and opportunity costs especially in relation to project timing. Once constructed and operating, the mining project may face one or more completion tests in relation to the loans provided. The genetics of such tests often relate to either the ability of the operating company to become solely responsible for the repayment of the loan or to be rewarded by lower interest rates or some other mechanism. Strong professionalism, accessible records, good checking procedures and high quality, competent site management will greatly assist the client company passing these tests. A record of well established technical competence with its bankers may well assist a company in the establishment of a mezzanine loan for the early development of its next project, thus allowing an earlier return of dividends to shareholders.

Jan 1, 1995

By Y Xie, L O’Connor, S C. Dominy

Sheeted vein gold deposits are characterised by multiple subparallel veins and often free milling gold. Variability in gold grade and recovery parameters are enhanced by poorly designed sampling and test work protocols. Poor quality samples generally equate to an enhanced nugget effect. A sample can be described as being representative when it results in acceptable levels of bias and precision. Total sampling variability can be quantified by the relative sampling variance, which measures the total empirical sampling variance influenced by the heterogeneity of the lot being sampled under the current sampling / test work protocol. Effort should be made to minimise the relative sampling variance through Theory of Sampling (TOS) and quality assurance / quality control (QA/QC) application. This contribution reports on a case study that exemplifies how high-quality grade and recovery data can be gained from a well-designed and planned drilling, sampling and test work program, followed by bulk sampling. Results across historical resource drilling, geometallurgical drilling, laboratory assay / test work, geometallurgical modelling and a bulk sampling/pilot processing study are reconciled. A whole core, entire-sample test work protocol was used to acquire fit-for-purpose gold grade and recovery data for inclusion into a Pre Feasibility Study reported in accordance with the JORC Code.CITATION:Dominy, S C, O’Connor, L, Xie, Y and Glass, H J, 2017. Geometallurgical sampling protocol validation by bulk sampling in a sheeted vein gold deposit, in Proceedings Eighth World Conference on Sampling and Blending , pp 185–196 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2017

Study on Selective Reduction and Magnetic Separation of Low-Grade Nickel Laterite Ore to Produce High Nickel Concentrate

Sep 13, 2010

J. H. Lord (Geological Survey of Western Australia): During the last few days in Kalgoorlie here we have heard on various occasions of the great job the mining engineers have done persisting against rising costs and increasing salaries without a rise in the price of gold. I think it has been somewhat overlooked that it has been difficult to find additional ore as well. I consider that geologists also should be commended on their action in persisting to search for more orebodies. This goes on in any mining community, but in Kalgoorlie in particular, I believe, over the last few years that it has been more difficult all the time to find additional orebodies and the Companies are calling for higher grades to offset the economic condition. I feel that this paper by Mr. Finucane shows that the geologists have persevered on an idea and discovered that they can find additional orebodies in the calc schist where previously it was thought that these did not occur. This has added many tons to the ore reserves, and although it is not very significant at the moment, the significance will probably improve as more work is done.The whole thing has shown us the importance of economic geology. Mr Finucane has had many years of experience here and he has given us a very able exposition of the economics of ore finding, and there are not many questions that one could pose to him, because most of the information he presented is obviously fact borne out by drilling, underground development and lining up the ore channels. He did briefly touch on ore shoots-the Oroya shoot and several others. It would be very good if we could, and I feel sure...

Jan 1, 1965

Dynamics of Three Phase Contact Line Motion in Liquid-Liquid-Solid Systems - Impact of Surface Roughness

Sep 13, 2010

The dynamic response of holdup in a continuous ball mill has a direct influence on the rate function of grinding kinetics and is useful for predicting the variation in the size distribution of the finished product with time.A model was proposed involving three interacting, completely mixed chambers and this was used to derive analytically the transfer function of the system, from which the unit impulse response and the unit step response of the holdup with feed rate were obtained.The theory was confirmed by comparing it with previously published experimental data for the residence time distribution of particles passing through a ball mill.

Jan 1, 1975

By M Bannear, C Stanton

Since 2008, Arrium has been developing and commissioning a new low-grade hematite ore benefication plant (or OBP) at its Iron Baron mine site.The Iron Baron mine, which was closed in the 1990s, could not consistently yield the high-grade hematite required for pelletising. However, in todayÆs market, the 12 Mt of waste dumps represent a significant low-grade hematite resource, ideal for benefication.Initially, an internal scoping study and several sampling campaigns were conducted to determine the ability to upgrade the available low-grade dump material to a product suitable for export. Test work was conducted at Mineral Technologies (formerly CPG), and included high intensity magnetic separation, spiralling and jigging. Due to promising results from a wet processing circuit, Arrium engaged Mineral Technologies to design a flow sheet that could provide 1 Mt/a of a mixture of high-grade lump (-32 + 8 mm) and fines (-8 mm) products for export.With construction of the plant completed in late January 2012, Arrium, in conjunction with Mineral Technologies, began two commissioning phases. Each phase ended with a toll gate to prove the plantÆs capacity to reach rate and desired grade. After an initial period of running on water, feed solids were introduced to the plant and troubleshooting of bottlenecks began. The first toll gate, whereby the plant was required to run for 24 hours at an average feed rate of 200 t/h (80 per cent of design rate), was completed on the 1 March 2012. Further troubleshooting and resolving of issues allowed the plant to steadily increase feedrate while maintaining good availability and grade. The second toll gate required the plant to run for 72 hours at an average feed rate of 200 t/h while meeting grade, yield and water consumption targets. Sampling campaigns were conducted during this period to track the performance of key equipment. Completion of the test, and full handover of the plant to Arrium, was completed on the 21 April 2012.Although the formal commissioning phases had been completed, ongoing optimisation of the OBP continued, ensuring that all major equipment was working to produce the optimum yield and grade. Sampling campaigns were conducted on the jigs and spirals, with results and correlations used for operations documentation.Overall, with successful completion of the final acceptance tests, the commissioning of the Iron Baron OBP has been established as a major success achieving all production and quality targets as per the original design intent.This paper will focus on the successful commissioning and ramp-up performance of the plant however reference will also be made to the key development stages involved with the development of the project.CITATION:Stanton, C and Bannear, M, 2013. ArriumÆs Iron Baron hematite beneficiation plant - a success from start to finish, in Proceedings Iron Ore 2013 , pp 547-552 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 12, 2013

By T King

This paper reviews the changes in the coal industry over the past 30 years and attempts to predict the trends over the next ten years. The last 30 years have seen a steady concentration of production into fewer, larger mines, which operate on 3: more continuous basis, and a major increase in productivity per employee. Coal exports have increased from zero to almost half the country's total production. As well as major changes in exploration and mining equipment and the increasing use of computer tools, the industry now operates in a relatively new regulatory and commercial environment.   Safety legislation now requires the writing and enforcement of policies and procedures by the mining companies, rather than adherence to inflexible regulations enforced by an Inspector. Accident rates have decreased dramatically. The transition from coal mining licences to permits, requiring landowner consent and resource consents, is well under way. Environmental controls are now an essential aspect of the industry.   Equipment suppliers now offer maintenance services, production guarantees and flexible financing.  Contract miners offer mine design and restoration as part of the contract. In a similar approach, Solid Energy now offer an ash disposal service and assistance with resource consents to their customers as well as investment in technology to ensure a consistent product to demanding specifications. Solid Energy has proposals for energy centres which install and operate the coal burning appliances and simply sell energy to the customers. The next 10 years should see an intensification of these trends of bigger mines, more exports and greater technology and a 'package' approach to customer service.

Jan 1, 1997

By P W. Wypych

The iron ore industry faces significant challenges in the control of dust to meet emissions regulations and goals, as well as ensuring sustainable operations. This paper describes some of the different techniques and innovative technologies that are being developed and implemented to improve the suppression of airborne dust, specifically through the use of high energy micromist sprays. The utilisation of computational fluid dynamics (CFD) modelling and simulation is identified and described as a key enabling technology for an improvement in dust suppression solutions both from a level of understanding the source and flow of dust emissions, and for the development of new systems that can be used in the iron ore industry. CFD modelling is shown to be effective for modelling both spray dispersion and cross-wind effects, allowing designers to develop high-efficiency dust suppression systems with a greatly improved level of confidence when compared to traditional techniques. New high energy micromist technology is also outlined as a key element in developing high-efficiency dust suppression systems. Experimental results and industry applications are presented to demonstrate the significant improvements that can be achieved in suppressing or reducing airborne dust emissions.CITATION:Roberts, J M and Wypych, P W, 2017. Research into improving the efficiency of water spraying airborne dust control techniques in the iron ore industry, in Proceedings Iron Ore 2017, pp 359–364 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

By D P. Sainsbury, B L. Sainsbury, A Vakili, H-D Paetzold, P Lourens

The cave propagation behaviour of a jointed rock mass is strongly governed by the unique nature of joints and discontinuities, together with the intact strength of rock bridges that make up the rock fabric. A discrete finite difference (DFD) modelling technique has been developed to allow for the detailed consideration of the rock mass structural fabric at many scales and through many different stress paths that can be used for complex mine-scale analysis. The DFD methodology uses interfaces to explicitly represent large-scale structures and ubiquitous joints embedded within the simulated rock mass matrix to characterise intermediate structures. Through simulated testing of DFD materials, properties such as strength anisotropy and scale effects can be obtained. This paper discusses the successful application of implementing a DFD modelling technique for the back-analysis of caving-induced subsidence behaviour of Lift 1 at the Palabora mine.CITATION:Sainsbury, D P, Sainsbury, B L, Paetzold, H-D, Lourens, P and Vakili, A, 2016. Caving-induced subsidence behaviour of Lift 1 at the Palabora block cave mine, in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016), pp 415–426 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016

By S L. Garwin

"An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation. Since the Eocene, New Guinea tectonics have been driven largely by the south-westerly-directed collision of accreted arc terranes with the northern margin of the Australian Craton, and subsequent westerly-directed transport of these exotic terranes by left-lateral strike-slip fault systems. The subduction of the Solomon Sea plate beneath north-eastern New Guinea in the mid- to late-Miocene led to magmatism and related gold-copper porphyry and epithermal mineralisation in the Maramuni arc and the formation of the Frieda River, Nena, Wafi-Golpu and other deposits.The development of the world-class porphyry and epithermal deposits in the Medial New Guinea magmatic belt, including Grasberg, Ok Tedi and Porgera, is localised by dilational zones formed about the intersections of north-easterly-trending, reactivated basement faults and north-dipping reverse faults related to the southward progression of the Papuan fold belt during the Late Miocene to Pleistocene. These deposits probably formed during short mantle-derived magmatic episodes in zones of regional isostatic uplift, which are attributed to the delamination of the lithospheric mantle beneath New Guinea.CITATION:Garwin, S L, 2015. The tectonics, geology and gold-copper metallogeny of New Guinea, in Proceedings PACRIM 2015 Congress, pp 151–164 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 18, 2015

THE object of the air-tight stopping is either to prevent a current of fresh air from getting into the fire area, or to prevent an escape of fumes and gases from the fire area into the workings of the mine. In the former case all is "plain sailing," but in the latter case there are certain difficulties to be overcome.In the Broken Hill Proprietary mine there were two styles of stopping used during the last fire-brick and bag and the following were the chief points that determined the use of one in preference to the other:-If the required stopping were to be more or less permanent, bricks were used, also if the area to be blocked were large-bricks being so much lighter and easier to handle than bags filled with -skimps. If, however, the air contained much gas, a bag stopping was put up. Great difficulty was experienced in getting essentially surface men, such as bricklayers, to work where there was the; slightest trace of gas; miners, however, would willingly do the work, and a bag stopping could be built without skilled labour.In old drives and gangways, where there was the liability of settlement, the bag stoppings were preferable to brick. The slightest movement around the sides or foundations of the latter would cause cracks, thus rendering the brick stopping useless;whereas, in the former, there was a certain amount of elasticity.

Jan 1, 1909

By Pooley F. D

The coal measures of the South Wales coalfield contain at least 50 horizons at which coal seams are known, to occur. More than 300 samples of coal were collected from these coal measures and this paper outlines thefindings of an investigation of the pattern and distribution of 12 trace elements in South Wales coals. A comparison of trace element contents of the South Wales coals is made with trace element values found elsewhereand an attempt was made to establish the organic affinity of the elements in different seams and in the coalfield 'as a whole. An important function of such an analysis is to determine the order of abundance of trace elements and this was performed for individual seams and for the whole coalfield.The interrelationship of certain elements in some seams is also examined with a view to understanding the effectiveness of such an approach to seam correlation.Ranges of values are quoted together with the mean values of the various elements. Variations of elemental values within a seam section and over the coalfield as a whole are discussed.

Jan 1, 1977

A GREAT deal of attention has lately been given to the discussion as to the education required for engineers, and especially for mining engineers. The Institute of Civil Engineers has had a committee's report on it which has come to some interesting and valuable conclusions.The Institute of Mining and Metallurgy had a few years back a very long discussion on the subject, and the subject appears to be one of perennial interest to similar societies. Two recent addresses by Prof. Kernot, as president of the Victorian Instituteof Civil Engineers, are among the most interesting and practical of the contributions to the discussion. Engineers seem to feel either that the coming generation has not the same capacity to benefit by the training that has made themselves what they are, or that such training has turned out in themselves inefficient men, and that they must consequently struggle to obtain a better one for their successors. For not only is there a desire to extend existing instruction to cover the advances of science, but there seems to be a general desire also to make a completely radical change in the methods.It is not necessary to observe that education does not mean the imparting and acquiring of information, but rather the cultivation of the faculties so that the best use can be made of them and of any information acquired. For instance, a man is not educated who has by heart his lectures and the contents of his text-books, but that man is who remembers little of the actual wording of his text-books, but is able to find anything required in them...

Jan 1, 1909

By K S. Smith

Mineral-deposit geology, geochemical processes, and biogeochemical processes are fundamental controls on the environmental conditions that exist naturally in mineralised areas prior to mining, and that result from mining and mineral processing. Input from economic geologists and geochemists is therefore crucial to effectively predict, assess, mitigate, and remediate the environmental effects of mineral-resource development. Recent open pit gold mining at Summitville, Colorado , has received intense public scrutiny for a variety of environmental problems, most important of which has been extreme acid drainage. Now a Superfund environmental cleanup site, Summitville exemplifies how economic geology and geochemistry principles: 1. could have been better utilized to first predict and minimise the environmental problems, and 2. can now be used to optimize the environmental cleanup.

Jan 1, 1995