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By C A. Foss, K Leslie, C Arnold

Magnetic susceptibility measurements provide rapid, non-destructive testing of drill core, but cannot directly map magnetite and/or hematite content. Combined magnetic susceptibility and magnetisation measurements provide much more diagnostic information and, with sparse calibration constraints, are able to quantify magnetite and hematite concentrations and potentially map differences in grain size and texture. We have developed a travelling three-component vector magnetometer that can be run alongside core to map its external magnetic field. The logger has been designed to operate in core sheds and at remote drill sites. It is used to rapidly scan a length of core, with each core being scanned in different rotations. The magnetic field contributions from any remanent magnetisation rotates with the core and cause differences between successive measurements, while the field contributions from any induced magnetisations with isotropic magnetic susceptibility remain constant. Deconvolution of the magnetic field data with simultaneous three-channel inversions of the multirotation data separates remanent and induced components. Interpretation of this data provides estimates of the intensities of induced and remanent magnetisations, the orientation of the remanent magnetisations and the ratios of the induced and remanent magnetisation strengths. We expect these magnetisation parameters to correlate with stratigraphy through a banded-iron formation. Furthermore, we anticipate that we will be able to use this information to map zones of oxidation and other changes along the core. This novel instrument is one component of an integrated CSIRO program to provide new capabilities for iron ore exploration and development based on studies of magnetic fields and magnetisations at scales ranging from centimetres for these core investigations to tens of kilometres for formation studies.CITATION:Foss, C A, Leslie, K and Arnold, C, 2015. Rapid logging of different magnetic phases in banded ironstones using a travelling three-component vector magnetometer, in Proceedings Iron Ore 2015, pp 271–276 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 13, 2015

By Henrique Kahn, Daniel Uliana, Carina Ulsen, Guilherme Nery

"Gold has been a material in high demand since the dawn of humanity. After hundreds of years of exploitation, the increasingly search for gold occurs in lower grade deposits with greater extraction difficulty. Therefore, for maximum efficiency, deep knowledge of the characteristics of these minerals and their associations is crucial, which is acquired through an accurate and rigorous routine of process mineralogy and batch extraction tests. The industrial gold process extraction occurs by gravity concentration, sulphides flotation and cyanidation. For gravity concentration, it is fundamental to establish the proportion of free or coarse gold grains and its association to heavy minerals; regarding flotation, the most relevant data are the proportion of gold associated to sulphides and their liberation by the surface area; for cyanidation, it is crucial to evaluate gold accessibility and the kinetics of leaching. Thus, the characterization of gold associations and liberation is vital to establish the plant design, to optimize operating plants and to reduce gold losses. Our aim is the characterization of gold occurrence in low-grade Brazilian deposits with complex mineralogical assemblages to support processing flowchart definition and to predict metallurgical recoveries. Gold distribution in light and heavy minerals was evaluated by heavy liquid separation and the occurrence of gold in free or locked particles was carried out on heavy products by SEM-based automated image analysis using the MLA system. All the products of heavy liquid separation were cyanidated in head samples with different milling conditions to evaluate the reaction kinetics and maximum recovery."

Jan 1, 2014

By W. Birch, G. D. Rangel-Sharp, L. Bermingham

For many years, the accepted method of Measuring the Velocity of Detonation (VOD) in blast holes has been to use an electric cable of a constant resistance per metre. Thus as the wire is consumed by the explosive in the blast hole, the change in resistance is monitored and when this data is plotted against the time period of the in hole explosion, the VOD can be calculated.

Jan 1, 2011

"The technical report form provides the headings to be used and content required when a completing a technical report to be filed in accordance with NI 43-101. The technical report is meant to be a summary of the scientific and technical information on the mineral property. The Instrument (NI 43-101) requires that technical reports be filed with Canadian provincial or territorial securities regulators to support certain disclosure of mineral exploration, development and production activities and results in order to permit the public and analysts to have access to information that will assist them in making investment decisions and recommendations. FORM 43-101F1 TECHNICAL REPORT INSTRUCTIONS (1) The objective of the technical report is to provide a summary of scientific and technical information concerning mineral exploration, development and production activities on a mineral property that is material to an issuer.This Form sets out specific requirements for the preparation and contents of a technical report. (2) Terms used in this Form that are defined or interpreted in National Instrument 43-101 Standards of Disclosure for Mineral Projects (the “Instrument”) will bear that definition or interpretation. In addition, a general definitioninstrument has been adopted as National Instrument 14-101 Definitions that contains definitions of certain terms used in more than one national instrument. Readers of this Form should review both these national instruments for defined terms.(3) The qualified person preparing the technical report must use all of the headings of the items in this Formandmay create sub-headings. If unique or infrequently used technical terms are required, clear and concise explanations must be included. (4) No disclosure need be given in respect of inapplicable items and, unless otherwise required by this Form,negative answers to itemsmay be omitted. Disclosure included under one heading is not required to berepeated under another heading. (5) The technical report is not required to include the information required in Items 6 through 11 of this Form tothe extent that the required information has been previously filed in a technical report for the property being reported on, the previous technical report is referred to in the technical report and there has not been any material change in the information. (6) The technical report for development properties and production properties may summarize the information required in the items of this Form, except for Item 25, provided that the summary includes the materialinformation necessary to understand the project at its current stage of development or production. (7) The technical report may only contain disclaimers that are in accordancewith section 6.4 of the Instrument and Item 5 of this Form."

Jan 1, 2003

By Joel A. Huffinan

"This presentation is being given to better inform the audience of the dependability of precious metal analysis by fire assay. A brief explanation, however, of standard fire assay exploration procedures will be given. An overview of other types of analyses by fire assay will be discussed as well, and the operation of a modern day assay laboratory.IntroductionThe use of lead oxide for the fire assay process dates back to the finds in Troy II and the Cappadocian Tablets about 3,000 B.C. Some advances have been made in the basic procedures due to instrumentation and electronics, but the fusion and cupellation procedures used in fire assay remain much the same as during this period.In 1600 AD. Agricola was the first to take a scientific approach to fire assay recording methods and procedures used (Hillerbrand and Allen, 1905) [1]. Since this period, much of the recognized research into the analysis of ores and metals was carried out in the late 1800's and early 1900's prior to World War II, and again after the deregulation of precious metals. The renewed interest in precious metals mining and metallurgy are due much to advances in precious metals heap leaching in late 1970's."

Jan 1, 1999

By A L. de Ambrosis, S J. Clarke

In the non-codified realm of tunnel design there are issues which are sure-fire instigators of controversy. This paper presents a discussion regarding one particular issue which in the authors’ experience often results in comment and debate. This issue only forms part of the rock load assessment process, but it is specifically addressed with the intention of presenting a rational basis for design, which may result in broader acceptance within the tunnel design community.The issue considered relates to the characterisation of in situ rock stresses for the design of tunnel support in the Sydney Basin. A summary is given of the literature on the topic, with emphasis on the main sources of uncertainty and contention. A design approach is proposed, with particular focus given to the numerical modelling of in situ ground stresses and the approach used to ensure that the adopted stress regime is consistent with the assumed ground model. The resulting variability in the initial stress field is discussed and comparisons made to the test database.CITATION:de Ambrosis, A L and Clarke, S J, 2014. Characterisation of in situ stresses for tunnel lining design in the Sydney?Basin, in Proceedings 15th Australasian Tunnelling Conference 2014 , pp 247–252 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 17, 2014

By R. D. Clarke, E. De Souza

"A framework for ventilation planning, with a focus on planning to the end-of-mine life, was developed for the Diavik Diamond Mine, Northwest Territories. This framework was successfully used by Diavik’s mine engineers to select a cost-effective ventilation plan that met the life-of-mine requirements. The framework achieved this result by reconciling the production plan with the ventilation plan. A set of design acceptability criteria was created and a PICK (possible, implement, challenge, kill) chart was used to quickly narrow down the generated ideas for detailed assessment and economic analysis. RÉSUMÉ Un cadre de planification de l’aérage, qui met notamment l’accent sur la planification jusqu’à la fin de vie de la mine, a été développé pour la mine de diamants Diavik. Les ingénieurs miniers de Diavik ont su mettre à profit ce cadre pour sélectionner un plan d’aérage rentable qui répondait aux exigences propres à la durée de vie de la mine. C’est en conciliant le plan de production et le plan d’aérage que cet objectif a pu être atteint. Un ensemble de critères d’acceptabilité de la conception a été créé et un tableau PICK (de l’anglais possible, implement, challenge, kill, une méthode donnant la priorité à certaines actions proposées ou à des idées visant à résoudre des problèmes) a été utilisé pour rapidement limiter les idées générées et les soumettre à une évaluation et une analyse économique détaillées.INTRODUCTION The Diavik Diamond Mine, Northwest Territories, has been an underground-only operation since 2012 and has a remaining mine life of 8 years. In the first year of underground-only operations, the production rate increased from 60 kt of ore per month to more than 160 kt of ore per month. In subsequent years, this rate was continuously increased (Table 1) because the operation went through various improvement initiatives. By the end of 2016, Diavik’s total production was 0.41 Mt (+22.8%) ahead of the 2012 budget for 2016 production."

Jan 1, 2018

By T. H. Dubaniewicz

Fiber-optic technology is progressing rapidly, including the development of fiber-optic sensors for many applications. These sensors have the advantages of high sensitivity, light weight, small size, high bandwidth, and freedom from electromagnetic influences. The U.S. Bureau of Mines is investigating the use of fiber-optic technology to monitor mine atmospheres. This report describes a methane monitor based on differential absorption of infrared light. The monitor can detect methane concentrations as low as 0.2 vol pct as far away as 2 km via fiber-optic cable. The upper range is 100 vol pct methane. Since the system requires no electrical power within the mine, it is intrinsically safe.

Jan 1, 2010

By V. S. Sastri, Elboujdaini. M.

"Economics of wear in mining industry and methods by which wear cost may be reduced will be discussed.IntroductionCanada loses more than $5 billion annually due to friction and wear (Table 1). It is estimated that about $1.3 billion, or about 25% of the losses, could be saved through better application of existing technology (Table 2). It should be noted that the costs given in Table 1 and 2 refer to 1986. The losses due to friction and wear and the savings would be much higher in 1996. Tribology combines the many branches and specialties in science and technology concerned with understanding and combatting friction and wear. Specifically, tribology is concerned with the design and manufacture of sliding and rolling bearings, piston rings, gears, cutting tools and other devices in which surfaces interact, in sliding or other relative motion. Tribology is concerned with the correct use of materials for interacting solid surfaces, with the interaction of the surfaces with the lubricants, with the chemistry, physics and use of lubricants. It is concerned with the reduction of friction and wear and the avoidance of associated failures in machinery. Similar tribological components such as bearings are used in different technologies and similar tribological problems such as abrasive wear occur in different industries. Thus, tribology is in itself a generic science and technology, concerned with the generation and dissemination of knowledge on friction, wear and lubrication, and the application of the knowledge, to a wide range of industrial products and equipment, from ploughs to space equipment, from prosthesis to engines, from washing machines to railways, from computers to power stations, from paper mills to mines. Avoidable losses due to friction and"

Jan 1, 1997

By A. David Miller, Chika Oya

"Field sampling and testing are part of the Quality Assurance/Quality Control (QA/QC) requirements for all Cement Deep Soil Mixing (CDSM) Projects. Field sampling and testing are also used for determining the performance and quality of soil mixing method(s) and are the primary basis for accepting or rejecting the soil mixing wall among all other QC testing. Two of the most commonly recognized and used sampling methods for CDSM walls are wet grab sampling and verification coring. Depending on the types of wall construction and project budget, one or both of these methods are normally used to help evaluate the in-situ matrix and quality of the mixed soils. Additional to ASTM strength and permeability testing from wet grab sampling and verification coring, more and more testing methods are being employed and accepted. However, these other testing methods tend to be unnecessary, lack consistency and repeatability, and are more subjective to manipulation and interpretation. In certain projects, there are also misconceptions involved with the results of wet grab sampling and verification coring, hence it is important to note how these wet grab sampling and verification coring work and represent the work in terms of quality of production.TYPES OF PROJECTSCDSM projects include (but not limited to) in-situ stabilization, liquefaction mitigation, excavation support, groundwater cutoff, and pollution containment. Although these projects use similar equipment on the jobsites, each project is treated differently in terms of catering to specification, uses of different mix designs, and emphasis on certain steps during production.Different types of projects with different specification changes the focus of quality, but soil types in jobsite also determine how to proceed with production. For example, a jobsite with predominate gravel layer must be treated differently as opposed to jobsite with clayey sand as the main soil type.WET GRAB SAMPLEWet grab sampling is one of the most used testing methods for QA/QC. The wet grab sample specimen is retrieved right after finishing the production of the desired element.Wet grab sampling equipment consist the use of 28 cubic inch (458.84 cubic cm) box attached directly to one of the auger stems. Hinges attached to the top and bottom of the box is fabricated to allow collection only during auger withdrawal. The collection box is strapped just above the mixing paddles on the auger stem and measured from the center auger head tip to confirm proper depth of collection. This box method has been used in Japan and U.S. for numerous projects."

Jan 1, 2017

By L Eriksson, D Penn, J Appelgren

Atlas Copco, a leading supplier of equipment and services to the mining and construction industries, is consistently pursuing its strategy to offer the most productive and economical solutions by continuously offering new innovative products. These are, in most cases, developed and tested in close cooperation with demanding end users before being officially launched on the international market. The demands for higher productivity and improved overall economy have resulted in systems for automation of the drilling cycle and also tools for integrating the drilling equipment to the production control system used by the customer. In terms of improving the blasted material quality, the company has placed emphasis on accuracy in the drilling process and documenting what has been drilled. By applying state of the art technology to the common automation platform, developed for the surface drilling market, major steps in improving overall drilling productivity and blasting performance have been achieved. This paper will give some examples derived from the latest development of solutions for the companyÆs surface drilling products.CITATION:Appelgren, J, Eriksson, E and Penn, D, 2012. Rotary drilling automation increasing operator productivity and drilling quality, in Proceedings Eighth Open Pit OperatorsÆ Conference , pp 13-18 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 18, 2012

By Z. Sample, S. Kaushik

"INTRODUCTION Industries around the globe have been making significant advancements in recent years due to innovations in automation technology. With the implementation of modern automation technology, professionals in process automation or plant operations can expect significant and exciting change, and the mining and mineral processing industries are no exception. From 2000 to 2010, the International Council on Mining & Metals (ICMM) reported that an increased output and increased value of most metals has resulted in a rise in global metal and mineral process industries from $214 billion to $644 billion. [1] Since most productivity increases in mining and mineral process industries have been achieved through the ability to process lower grade ores with improved efficiency and larger equipment, these industries have begun to adopt advanced automation and control technologies. Despite a growth slow-down, the mining and mineral processing industries are poised for continued and sustainable growth and development due to an increasing demand for energy minerals and emerging technologies requiring minerals and metals previously not demand. However, as these industries becomes more automated, new challenges are arising on the horizon. DEMOGRAPHIC TIME BOMB John Payne from BP is credited with first using the term Demographic Time Bomb to describe the upcoming crisis in the process industry in finding experienced operations personnel. From a survey of 912 mining professionals, Stratum International found that a mere 0.4% of senior level candidates were between the ages of 25 and 34 and a similar proportion aged over 75 years. This indicates that there is both a deficiency of young skilled workers and a skilled workforce that is retiring earlier than the previous generation. Combined with data published by the US Department of Labor stating that the median age of the mining workforce is approaching 50 years old, this implies that these skilled mining and mineral process professionals are an aging population with irreplaceable knowledge and experience that are expected to retire in the next 5-10 years. While it is projected that the labor pool will be sufficient to fill open positions, the real question is if this young workforce will have necessary skill sets and experiences."

Jan 1, 2015

By Derek J. Fray

The need for on-line sensors is outlined and it is demonstrated that the control of many processes is prevented by the availability of these devices. The use of solid electrolytes is described for the sensing of elements in molten pyrometallurgical phases. In the cases where there is no suitable electrolyte, the addition of a second phase of a compound containing both the element to be measured and the element whose ion is mobile in the electrolyte can be used. For the measurement of high concentrations of an element a method based on current measurement is proposed.

Jan 1, 1994

By F. Michael Hosking

Modeling of a furnace brazing process is described. The computational tools predict the thermal response of loaded hardware in a hydrogen brazing furnace to programmed furnace profiles. Experiments were conducted to validate the model and resolve computational uncertainties. The results from selected furnace simulations and measured thermal events were compared. Critical boundary conditions that affect materials and processing response to the furnace environment were determined. "Global" and local issues (i.e., at the furnace/hardware and joint levels, respectively) are discussed. The ability to accurately simulate and control furnace conditions is examined.

Jan 1, 1998

By J. F. Dorion

This paper presents the results of on-going investigations on the performance of support systems in Québec underground mines. The focus of these investigations is on site observations complemented by laboratory investigations. Of particular interest is deducing the corrosion rate, at selected mine sites, as determined by the installation of monitoring coupons.

May 1, 2009

By Brandon Smith, William Bohlen

Riverbank erosion along the Brazos River has modified the structural support conditions for an existing bridge structure in Southeast Texas. The 8-span, 1,200-foot long bridge was completed in 1992 along Highway 99, a key corridor for the Houston area. Foundation support conditions have been altered due to natural, ongoing river morphology for three bents on the affected riverbank. Recent events include three storms within a three-year period that each exceeded the 500-year return probability. This resulted in accelerated erosion along the northern riverbank. Over forty vertical feet of soil has been removed in some locations. Drilled shaft foundations are now functioning as columns. This review considers the behavior of columns and deep foundation elements due to the modified support conditions. The review ultimately presents a rational methodology for the review of the present and anticipated future bridge configuration with respect to current strength, service, and extreme event limits, with corresponding safety factors for the design. Introduction and Background The Fort Bend Grand Parkway Toll Road Authority (Owner) oversees the State Highway 99 Judge Jodie Stavinoha Bridge over the Brazos River. The 8-span, 1,200-foot long bridge was originally designed with four southern approach spans of 115 feet; a three-span continuous river crossing with span lengths of 195 feet-235 feet-195 feet; and a single northern approach span of 115 feet. Figure 1 provides an overview of the northern portion of the bridge. Table 1 provides a summary of the original bridge substructure configuration. When the bridge was completed, the centerline of the Brazos River was located at midpsan of the main span and the northern high bank was originally located at Bent 7. Erosion process has forced the northern high bank to Abutment 9 (also called Bent 9), and the river centerline during normal flow conditions is located south of Bent 8. The overall estimated river excursion at present day is approximately 270 feet to the north from its original location. An erosion wall that was installed in 2017 limits further erosion of the north river bank within the 300-foot width of the roadway corridor right-of-way. This study was developed to better understand the existing conditions, and to forecast the need, nature, and criteria for potential future improvements.

Jan 1, 2019

By A. N. Clay, N. N. Moeketsi, S. Joubert

For many years, mine-impacted water has been regarded as a problem and linked to long-term environmental liabilities. However, this water can be a renewable and a sustainable resource, provided that it is managed in a responsible and sensible manner. South Africa’s National Water Resource Strategy (NWRS, 2013) considers water that can be used to contribute to economic activity to be a water resource. Although all water resources are considered as belonging to the State, government does not appear to have meaningfully explored the use of mineimpacted water to contribute to the country’s economic activity. Africa is blessed with more sunshine than anywhere else, apart from Australia, yet we see no rollout of vast quantities of solar panels to ensure every African family has access to affordable power. This suggests that governments are incapable of managing such a free resource. At the same time, apart from the equatorial areas, water is a seriously constrained resource and yet we expect the same entities to manage a commodity none of us can live without. This paper explores the conversion of mine-impacted water from waste to a resource and how the inclusion of other stakeholders (such as water users, landowners, and ordinary South Africans) could benefit the process.

Jan 2, 2022

By A Whaanga, W Vigor-Brown

IGO Ltd’s (IGO’s) Nova-Bollinger Deposit (Nova-Bollinger) is a magmatic nickel-copper-cobalt (NiCu-Co) sulfide deposit found 160 km east-north-east of the town of Norseman in Western Australia (WA). The deposit is hosted by the Mesoproterozoic rocks of the Fraser Zone, which is part of the Albany Fraser Orogen (AFO). Since mining commenced in 2016, IGO’s Nova Operation (Nova) has mined and processed to 31 December 2020, 5.63 Mt of ore grading 2.04 per cent Ni, 0.86 per cent Cu and 0.07 per cent Co. Nova’s mine geology team (MGT) has used commercially available implicit modelling (IM) and general-purpose resource modelling (RM) industry software systems, to prepare the 31 December 2020 (CY20) update of Nova-Bollinger’s JORC Code reportable Mineral Resource estimate (MRE). This CY20 MRE update was predominantly based on ~386 km of diamond core drilling, with the drill holes having a nominal grid spacing of 12.5 by 12.5 m throughout the mineralised zones of the deposit. Using IM tools, Nova’s MGT interpreted and modelled 22 separate domains from the drill hole logging, assaying results, and the MGT’s underground mapping. These IM closed volumes were then used to control the estimation of MRE variables into conventional industry digital block models using RM and other ancillary software systems. During 2021, a commercial machine learning (ML) software was trialled by Nova’s MGT for preparing block models of Nova-Bollinger’s MRE domains. The motivation for the trial was that the ML process could expedite modelling through the direct creation of a domain coded block model from the drill hole logging. Compared to the industry standard approaches of wireframing or IM, where the modeller usually makes many subjective choices to produce the domain model, ML offers a more objective ‘hands-off’ process for determining the connectivity of domains defined in drill holes. Additionally, the ML process provides a quantitative confidence metric associated with its output that may have utility in mine production and resource classification. In this paper, the results of the Nova-Bollinger ML modelling trial are compared to the MGT’s current workflow for MRE work. The MGT’s conclusions as to the advantages and disadvantages of the IM and ML methods for preparation of MRE domains are discussed. The ML software was also tested as a method of rapidly interpreting geology outside the principal zones of MRE interest. These testing results are also presented in this paper.

Mar 22, 2022

Late Cretaceous and early Tertiary coals in the Greymouth, Ohai and Kaitangata coalfields represent a major national energy resource comprising-up to 2500 x 106 tonnes of coal in ground. The three coalfields are closely related in terms of age and sedimentary and structural character. The most striking feature common to all is the complexity of the geology which has severely restricted exploration and mining of these coal resources. This complexity is manifest in the irregular lensoid nature of coal seams and by the incidence of unpredictable medium and small scale faulting and folding. There are many geological similarities between these coalfields which are considered to arise from a common origin which can be related to the plate tectonic evolution of the southwest Pacific region. In order to efficiently assess and exploit these coal resources it will be necessary to know their geology in great detail. This can he achieved by increasing the understanding of the sedimentary and structural evolution of the coal bearing basins. This knowledge may be gained by the application of traditional (ie drilling, field mapping) and innovative techniques (ie high resolution seismic, in seam seismic) with on going research-oriented studies (ie basin analysis, coal petrography).

Jan 1, 1987

By Jack F. B. Silman

Proving up any large, open pit ore deposit by normal exploration drilling under the best of conditions is a noteworthy accomplishment. But, when adverse conditions preclude standard drilling methods, and the same end result is achieved by a relatively new and little known type of drilling, special comment is in order. Three major problems confronted exploration drilling at the Questa molybdenite mine of the Molybdenum Corporation of America-sampling, terrain and time. Surface and underground longhole drilling provided the needed solutions, thus making the greatest single contribution to an exploration and development program that was successful in proving a major, open pit molybdenum deposit.

Jan 5, 1965