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By J Seery, N Savage, A Wilson, L Nicholas

Geological modelling provides a means of spatially representing the three dimensional distribution of geological information to downstream stakeholders. The geologist completing the modelling work intimately understands the varying degrees of confidence, assumptions and extrapolation required to honour the data. Geological models are often taken and used by stakeholders without fully understanding this modelling process. This can lead to confusion amongst stakeholders when the geological model shows variable reconciliation. A method for visually communicating the confidence of the spatial distribution of geological models has been created by the Rio Tinto Iron Ore structural geology group for use primarily in geotechnical engineering investigations. A numeric confidence rating is assigned to each geological data point used in the creation of a geological surface. This is based on data type, collection method and reliability to indicate potential error in distance from its modelled location. In regions of sparse data, confidence ratings are inserted based upon the geologistÆs experience and knowledge of the geology, whereas mapped geological contacts or drill hole intersections are assigned a higher confidence rating. A regular grid of points is registered to the geological surface and each of these grid points is assigned a confidence rating using an inverse distance weighting using a nearest neighbour approach. The resulting grid is colour coded according to the confidence rating to provide a visual representation of the variable confidence of the geological surface in three dimensions. Subjectivity and bias from the geologist is minimised by critically analysing the input geological data and then applying this methodology to represent the confidence in the spatial characteristics of geological models. Understanding of this confidence enables mining professionals to make informed decisions and identify areas that require further geological investigative work. CITATION:Savage, N, Nicholas, L, Wilson, A and Seery, J, 2013. Visual communication of geological confidence - a move toward a less subjective approach, in Proceedings Iron Ore 2013 , pp 169-174 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 12, 2013

Visual computing opens the design process to a wider audience and allows rapid communication of mine plans to all stakeholders. The integration of software and hardware technologies that take advantage of a graphical environment will continue to improve both long-term and short-term mine design (Figure 1). A good design must be adaptive to respond to decision changes as the mine develops and more information becomes available. The constraints on mine design predicate careful analysis in order to operate the mine as efficiently and safely as possible.Continuous improvement in mining is assured by developing innovative technologies that target mine survey, drill and blast, modelling, short-term design and pit and stope optimisers. The design life of a mine has to be sufficiently long to ensure the mine is commercially successful, justifying the high start-up capital costs. Being able to execute a plan so that it honours the design realises the rewards of computerised mine planning and the long-term investment in data acquisition.

Sep 26, 2011

By C. C. Jobes

Operating large face equipment, such as continuous mining machines, is one of the most basic and most dangerous elements of an underground coal mining operation. The operator usually performs cutting and tramming tasks in a restricted workspace with reduced visibility. During the execution of these tasks, operators often cannot see all of the locations needed to safely operate the continuous mining machine (CM ), which has sometimes resulted in accidents. In an effort to prevent these accidents, researchers at the National Institute for Occupational Safety and Health (NIOSH), Pittsburgh Research Laboratory, examined the continuous mining machine operator?s current information cues, or visual attention locations, so that risk of injury relative to the task, equipment and workplace environment can be evaluated in the future. The eventual goal is to develop interventions to enhance the information cues, and thereby increase the safety and health of machine operators. This paper details the operator interview process, determination of visual attention locations (VALs) and simulation of various mining scenarios.

Jan 1, 2011

By John J. Sammarco

Miners depend most heavily on visual cues to recognize underground mining hazards; consequently, illumination plays a critical role in miners? safety. Some hazards are located in the miners? peripheral field-of-view (10 degrees to about 60 degrees off-axis) or on-axis (0 degrees). The objective of this research was to determine if there were visual performance improvements when using solid-state cap lamps with light-emitting diodes (LEDs) as compared to incandescent light bulbs commonly used in miner cap lamps. Recent research has indicated that an increased short-wavelength content of the spectral power distribution of LEDs relative to incandescent lamps improves peripheral visual performance for low-light (mesopic) conditions. The visual performances of nine subjects were quantified by measuring the subjects? speed and accuracy in detecting floor objects located on axis and at ±20 degrees off axis. The objects were located near field (1.83 meters) and far field (3.66 meters). Upon presentation of the objects, subjects would count and point to each object using a red-laser pointer. The object detection response time and number of missed objects were recorded. The results of the visual performance comparison for an LED, a prototype LED, and an incandescent cap lamp are presented. There we no missed objects when subjects used the LED-based cap lamps but, there were three missed object occurrences when subjects used the incandescent cap lamp. The mean detection time when using the incandescent cap lamp was 55.3% greater than the prototype LED cap lamp and 43.5% greater than the LED cap lamp. It can be inferred from this data that the spectral distribution of LED-based cap lamps could enable significant visual performance improvements as compared to incandescent cap lamps1.

Jan 1, 2007

By Sylvan Cromer

THE need for a clear understanding of the physical nature of the flow of gas-liquid mixtures in vertical pipes is ever becoming more apparent. This type of flow is encountered when gas and oil are produced from a well; when water is removed from gas wells with siphon lines and when liquids are elevated by means of air or gas lift. Although a number of investi-gators1-7 have published data on the flow of gas-liquid mixtures, in only a few cases has the experimental setup been devised to permit visual study. In the fields of heat transmission, such as the boiling of liquids and the study of the critical phenomena of the hydrocarbons, researchers have been able to throw additional light on heretofore unexplainable happen-ings through actual observation in glass apparatus. This investigation was therefore undertaken in order to obtain qualitative as well as quanti-tative results for air-water flow. EXPERIMENTAL APPARATUS AND PROCEDURE The flow column used in these tests was made of standard 2-in. pipe and was approximately 98 ft. in height. Pyrex observation sections 2 ft. long having the same internal diameter as the wrought-iron pipe were placed at 14-ft. intervals in the column. The bottom of the tube was cut off square and terminated in the mixing chamber. No perforated nipple or footpiece of any kind was used. To the top of the column was fastened a semicircular return bend having a 4-ft. radius. The flow column was supported by a standard cable-tool drilling derrick (Fig. 1) into which were built observation platforms at each Pyrex section.

Jan 1, 1939

By Maurice J. Peterson

THE VISUAL-ARC spectroscopic method of rapid qualitative analysis of complex inorganic compounds has been popularized in the past few years and is being employed by an increasing number of laboratories. The mineralogy and chemistry departments of several universities recently have added visual spectroscopy to their laboratory curricula. This revival of interest in a somewhat dormant analytical method has been stimulated through the publication of three papers 4 by members of the College Park staff of the Bureau of Mines. These virtually are the only recent sources of information on visual-arc spectroscopic analysis. They include data on the spectroscopic assembly, the analytical procedure, and the practical application of the method to determinative mineralogy and related fields. Requests for reprints of these papers continue to be received; at present only a limited number of copies are available for distribution. In order that these requests may be adequately answered, material from the three papers has been combined and, with some additional data, is presented in this bulletin. Numerous specific inquiries have been received regarding types of equipment available, problems in instrumentation, and information on the approximate sensitivity limits of the elements that can be detected by this method. Some of this material was not included in the original papers. Accordingly, the table of wavelengths has been revised to include the approximate visual-arc spectroscopic sensitivities, and a section on commercially available equipment has been added.

Jan 1, 1953

By J. P. Harrison, J. A. Hudson.

ABSTRACT: When considering the rock stress component of rock mechanics design, the basic procedure is to consider the pre-existing stress-state in the rock mass and then estimate the disturbance to this stress state as a result of engineering excavation. Failure criteria are applied to the final stress state to establish whether failure will occur. However, during the evolution of the stress state, the failure locus may be reached before the anticipated failure state and, in this case, failure will occur unexpectedly. This indicates that the complete stress path (defined as the variations in magnitudes and orientations of the stress tensor components resulting from engineering-induced or natural changes) must be considered. We list a set of stress path principles with their corollaries and then introduce a new and powerful method for simultaneously illustrating changes in the six independent components of the stress tensor. This method plots the magnitudes of the principal stresses above their orientational paths on the hemispherical projection, to provide a three-dimensional stress path locus for each of the three principal stress components. In connection with this presentational device, we illustrate a number of concepts associated with the stress path in rock engineering. For example, we show how the minor principal stress approaches zero at an unsupported excavation face, the interchange of the trajectories of two principal stresses when their magnitudes become equal, and the influence of the bounds on the principal stresses given by strength criteria. RESUME: Si on s’interesse à la composante “contrainte” lors d’un dimensionnement en mécanique des roches, la méthode de base consiste à considérer l’état de contrainte pré-existant dans le massif rocheux, puis d’estimer la perturbation à cet état générée par l’excavation projetée. Des critères de rupture sont appliqués à l’état de contrainte final pour établir si une rupture va se produire. Cependant, lors de l’évolution de l’état de contrainte, la surface critique peut être atteinte ce qui provoquera une rupture anticipée et, dans ce cas, cette dernière sera inattendue. Cela indique que le chemin de contrainte complet (défini par les variations de l’intensité et de l’orientation des composantes du tenseur des contraintes liées à des causes anthropiques ou naturelles) doit être pris en compte. Nous présentons un ensemble de règles pour les chemins de contraintes ainsi que leurs corollaires et, ensuite, nous introduisons une méthode, nouvelle et puissante, pour présenter simultannement les changements des six composantes du tenseur des contraintes. Cette méthode consiste à tracer l’intensité des contraintes principales sur le chemin d’orientation des contraintes à l’aide d’une projection hémisphérique afin d’obtenir le lieu, en trois dimensions, de chaque contrainte principale. En relation avec cet outil de représentation, nous illustrons certains concepts associés au chemin de contrainte en ingénierie au rocher. Par exemple, nous montrons comment la contrainte mineure tend vers zero à la surface d’une excavation sans soutenement, le changement de direction des deux contraintes principales quand leur intensité deviennent égales, et l’influence des conditions aux limites sur les contraintes fournies par un critère de rupture. ZUSAMMENFASSUNG: Bei ingenieurmassigen Taetigkeiten in Felsgesteinen ist es noetig die ungestoerten Gesteins Stress Componenten, die vor einem anthropogen Eingriff im Gestein vorhanden waren, zu kennen und erst dann Vorhersagen ueber Stoerung des Stress Zustandes, der durch einen ingenieurmaessigen Eingriff hervorgerufen wird, herzuleiten. Kriterien fuer das Versagen werden im letzten Stadium, des Stress Zustandes angewendet, um zu erfahren ob ein Versagen wohl eintreten wird. Es ist jedoch zu beachten, dass waehrend des Stress Aufbaus ein oertliches Versagen eintreten kann, welches vor dem eigentlichen, erwarteten Versagens Zustand auftritt. Diese Moeglichkeit weist darauf hin, dass der gesammte “Stress Path” (definiert durch die Variationen der Stress Tensor Komponenten in Richtung und Groesse, hervorgerufen durch ingenieurmaessig hervorgerufene oder natuerlich Vorgaenge) betrachtet werden muss. Wir fuehren eine Liste der “Stress Path” Prinzipien auf und stellen dann eine neue und wirksame Methode zur gleichzeitigen Darstellung der sechs unabhaegigen Komponenten des Stress Tensors vor. Diese Methode stellt die Groesse der “Principal Stresses” in Abhaengigkeit von ihrem rauemlichen Weg auf einer hemispherischen Projektion dar und erlaubt hiermit eine drei dimensionale Darstellung fuer jeden Ort des “Stress Path’s” in die drei Haupt Stress Komponenten. Im Zusammenhang mit der hier gegebenen Darstellungsart, verdeutlichen wir eine Reihe von Konzepten in der Felsmechanik. Wir zeigen zum Beispiel, wie der “Minor Principal Stress” Null zustrebt an einer Wand von einer nicht abgestuetzten Ausschachtung, den Austausch von Trajektorien zweier “Principal Stresses” wenn ihre Groessen sich gleichen, und den Einfluss der Groesse von “Principal Stresses” bei gegebenen Kriterien des Festgkeits Versagens.

Jan 1, 2003

By Z. Y. Xie

The visualization techniques were employed for the analysis of computer simulation studies of dislocation core structure in ordered alloys. Atomistic computer simulation was used for the study of the local configuration of the material in the vicinity of the dislocation. Stresses were applied in the simulation in order to study the necessary stress level for the dislocation to move and onset plastic deformation of the material. The results were analyzed in terms of the strain tensor as a function of the position (x, y) in the material with the dislocation located at (0, 0). Various visualization packages are used to plot the invariants of this strain tensor and to visualize the changes that the dislocation core undergoes under stresses until it finally moves.

Jan 1, 1993

By P. Peczak

A Monte Carlo simulation technique has been used to study dynamic recrystallization in polycrystals. A continuum microstructure of the polycrystal is modeled employing a discrete lattice. The response of the material to hot deformation is simulated by adding stored energy and recrystallization nuclei continuously with time. The experimentally observed nonuniform character of deformation substructures is modeled by employing a phenomenological expression for inhomogeneous distribution of the stored energy. All simulations were performed on HP-Apollo 9000 Series 700 workstations. A program written in FORTRAN with use of PHIGS graphics library calls was used to interactively monitor the current state of the matrix and all relevant parameters: deformation stress, average grain size and effective nucleation rate. Visual analysis of the simulated microstructure allows a better understanding of the data developed by averaging over a number of very long Monte Carlo runs. Since the essential features of dynamic recrystallization are accurately reproduced by the model, it is used to discuss the role of the controlling mechanisms of the dynamic recrystallization in real polycrystal.

Jan 1, 1993

By W. Pawlos

"The paper will present the methods of visual observation and recording of movement paths of coal grains of different physical properties in the paramagnetic liquid. The paths were recorded with a video camera in the working chamber by means of a specially constructed device, acting as a periscope, which were then transformed into digital images.Experimental movement paths were confronted to the paths obtained in a theoretical way by means of solving differential equations of movement. The outlet level of a grain of the same physical properties from the separator is a random variable with normal distribution which modal value is equal to the outlet level of a spherical grain, calculated from the solution of grain movement equations. At these assumptions it is possible to calculate the height of the passage from the separator working chamber to separate a given product with a given separation accuracy, measured by a probable error and to determine separation conditions."

Jan 1, 2003

By Angelina Anani, Nilufer K. B. Akbulut, Sefiu O. Adewuyi

Crucial information about safety, design and operation from ground movement data can be utilized in underground mines. Communicating the information and exploring new findings can be a challenge, however, in a decade where there is an ever-increasing volume and velocity of data due to advancements in mining technologies. This challenge escalates for geotechnical data as they are multidimensional, depending on the space and the rate at which they take place. To tackle this challenge, geotechnical engineers should focus on using simple yet compelling visualization of rock mass data in 3D. Competent visualizations of ground conditions as a trigger action and response plan (TARP) could ease the communication of safety concerns and the exploration of rock mass displacement and strain surrounding an opening at an underground mine. Therefore, this study focuses on using scientific visualization methods by rendering geotechnical data over the surface of a 3D mesh model to display TARP levels. The study was conducted at the East Decline of the San Xavier (SX) Underground Mine, a laboratory mine operated by the University of Arizona. The project aims to produce visualizations that optimize the use of geotechnical data in near-real time.

Sep 1, 2025

By Angelina Anani, Nilufer K. B. Akbulut, Sefiu O. Adewuyi

Crucial information about safety, design, and operation can be utilized in underground mines from ground movement data. Communicating the information and exploring new findings can be a challenge in a decade where there is an ever-increasing volume and velocity of data due to advancements in mining technologies. This challenge escalates for geotechnical data as it is multidimensional, depending on the space and the rate it takes place. To tackle this challenge, geotechnical engineers should focus on utilizing simple yet compelling visualization of rock mass data in 3D. Competent visualizations of ground conditions as a Trigger Action and Response Plan (TARP) could ease the communication of safety concerns and the exploration of rock mass displacement and strain surrounding an opening at an underground mine. Therefore, this study focuses on using scientific visualization methods by rendering geotechnical data over the surface of a 3D mesh model to display TARP levels. The study is conducted at the San Xavier (SX) Underground Mine Laboratory’s East decline. The project aims to produce visualizations that optimize the use of geotechnical data in near-real-time.

Feb 1, 2025

By Makiko Takahashi

A tool is being developed to predict and visualize the microstructural evolution of steels during quenching. This tool utilizes experimental data and reference data that are stored in a database to predict the microstructural development. The visualization tool animates qualitative representation of two- dimensional microstructure drawings as well as the quantitative volume fractions of phases present as a function of time. This is achieved by superimposing the Jominy End-Quench test results over the Continuous Cooling Transformation diagram of the alloy. The predicted microstructure is presented through the web browser to maximize the ease of use. In addition, a parallel coordinate system is used to aid in identifying similarities within the data set by presenting the large number of data at a glance. The results for 4140 steel that was quenched in a wide variety of quenchants will be presented to illustrate the prediction and visualization tools. Keywords: Quenching, Microstructure Prediction, Simulation, Data Visualization, Database, Applet, Animation

Jan 1, 2003

By Javier Antoñanzas, Susana Caballero, Eduardo Fernández, Jorge Aragón, Juan Carlos Múgica, Lourdes Yurramendi

Air Pollution Control (APC) residues treatment by plasma was studied as a technology for vitrification. During the project a protocol to verify the plasma technology was developed and afterwards applied to a specific case study: the APC residues from Municipal Solid Waste Incinerators (MSWI). Different operational conditions were tested and the vitrified products obtained were analyzed using standardized leaching tests in order to evaluate their new properties concerning safety storage. Two leaching tests were used for the evaluation, the European EN 12457-4 compliance test for leaching of granular waste materials and the French XP X 31-211 test for the determination of the leachability of a solid waste material initially massive or generated by a solidification process. Finally, conclusions about the environmental performances of the technology were obtained.

Jan 1, 2008

By William K. Connor, O&apos

The U.S. Bureau of Mines (USBM), in cooperation with the American Society of Mechanical Engineers (ASME), conducted over 200 hours of melting tests to vitrify residues from five municipal waste combustion facilities. Combined residues (grate residue and f1yash) from three municipal waste combustors, a waste water treatment sludge combustor, and flyash from a refuse-derived-fuel (RDF) boiler, were sequentially melted in a I-metric-ton (mt) water-cooled-wall electric arc furnace. Each of the residues underwent magnetic separation, screen size analysis, and bulk chemical analysis prior to melting. The furnace products were examined by optical and electron microscopy and by X-ray diffraction. Bulk chemical analyses were acquired for the metal, fume, and vitrified furnace products. The material balance for the furnace operation indicates that from 69 to 86 pct of the feed reported to the vitrified furnace product, which had leaching potentials well below the EPA limit for each metal, as determined by the EPA TCLP. The electric arc melting furnace currently is being utilized in a cooperative research project between the USBM and the Idaho National Engineering 'Laboratory (INEL) for melting tests on simulated low-level radioactive wastes,

Jan 1, 1991

During incineration of municipal solid waste (MSW), some heavy metals and other environmentally harmful elements are liberated into bottom ash. The stricter environmental regulations require a higher immobilization efficiency of the ash before its safe disposal and application. Vitrification is one of the promising options, and has the advantages of high destruction efficiency of organics, high immobilization of heavy metals, and large volume reduction. The main components of the vitrified slag are SiO2, CaO, Al2O3, Fe2O3, Na2O and MgO, and the compositions have direct effect on the glass formation during vitrification, and further on the physical and mechanical properties of the slag. To provide essential data for the utilization of bottom ash as vitrified slag, the phase relations and thermodynamic properties of the oxide system need to be systematically investigated. In the present study, the liquidus temperature of the typical vitrified bottom ash slag was determined by using differential scanning calorimetry (DSC) measurement. High temperature equilibrium experiments were conducted to investigate the phase relations of the sub oxide system of CaO-SiO2-Na2O by means of Scanning Electron Microscopy (SEM), Electron Microprobe Analysis (EMPA) and X-ray Diffraction (XRD). The results show that the melting temperature of the vitrified bottom ash is around 930°C. In the CaO-SiO2-Na2O system with less than 50 mol% SiO2, the liquidus temperature de-creases with increasing amounts of Na2O along the tie-line of Na2O-Ca3Si2O7. Two compounds Na2Ca3Si2O8 and Na4Ca8Si5O20 are identified in the oxide system.

Jan 1, 2014

By D. C. Fraser

"Geophysical Engineering and Surveys Limited of the Keevil Mining Group have routinely conducted ground surveys with VLF-EM receivers for the past two years. Both Crone's Radem and Ronka's EM16 have been used.VLF-EM dip-angle data often yield complex patterns which require considerable study for a proper interpretation. A method was developed which allows field operators to transform the noncontourable dip angles into contourable data, producing conductor patterns which are immediately apparent to exploration personnel untrained in VLF-EM interpretation.VLF-EM contoured data generally peak very close to the top of a conductor, thereby allowing drill holes to be spotted accurately. However, the data generally should not be used alone to select drill targets because structures may be sufficiently conductive to yield strong anomalies. Thus, magnetic and/or vertical-loop EM correlations may be considered as necessary criteria for drilling.VLF-EM surveys can replace IP surveys in certain environments. For example, the Restigouche orebody in the Bathurst camp of New Brunswick yielded a VLF-EM anomaly as distinct as that obtained by IP, although the body did not respond to vertical-or horizontal-loop EM. However, the cupriferous breccia pipes of the Triba mine near Batchawana, Ontario yield strong IP anomalies but not VLF-EM anomalies, illustrating that disseminated ore targets should be sought with IP rather than with VLF-EM."

Jan 1, 1971

By J. A. Madonna

Universities and colleges in three countries, Australia, Canada and the United States, recognized the need to establish and/or reorganize geoscience programs at the vocational and two-year technical levels. To accomplish this goal, a cooperative study with industry in one state or province from each country was initiated. These include 1) Tasmania, Australia, 2) British Columbia, Canada and 3) Alaska, United States. Over one hundred mineral industry organizations cooperated in the study by providing information regarding their specific training needs for support personnel. The data gathered has been used to identify training areas for semi-skilled, skilled and technical personnel in geochemical mineral exploration, including, but not limited to, geological skills, geochemical skills, environmental skills and computer skills. With the areas of major educational need defined for geochemical exploration, an educational field skills model has been developed for the three levels of training. The depth of each level of education and the training objectives for the work force at each level will be discussed.

Jan 1, 1993

By James A. Madonna

Several universities and colleges in Australia, Canada and the United States, recognized the need to establish or reorganize geoscience programs at the vocational and two-year technical levels. To accomplish this, a cooperative study with industry in one state or province from each country was initiated. These include Tasmania in Australia, British Columbia in Canada and Alaska in the United States. The objective of this work was to develop a diversified geoscience educational model at the two-year technical, vocational and continuing education level that provides the source from which any nation can draw the proper educational tools to create a new geoscience program, modernize an existing program or strengthen a weak program. More than 100 mineral industry organizations provided information regarding their specific training needs for support personnel. The data gathered have been used to identify training areas for semi-skilled, skilled and technical personnel in geochemical mineral exploration. These included geological, geochemical, environmental and computer skills. With the areas of major educational need defined for geochemical exploration, an educational field skills model was developed for the three levels of training. The international need for a study of this type was recognized as early as 1980, following numerous contacts from domestic and foreign geoscience educators regarding the structure and success of training within the University of Alaska Fairbanks Mining Extension program, located in Fairbanks. Contacts, correspondence and visits included educators from Australia, Brazil, Canada, Mozambique and the conterminous United States. The need was magnified between 1985 and 1989 at the University of Alaska Fairbanks, when an attempt failed at initiating and developing a two-year geoscience vocational-technology program leading to an Associate of Science degree.

Jan 1, 1994

By J. A. Madonna

Universities and colleges in three countries -Australia, Canada and the United States, recognized the need to establish and reorganize geoscience programs at the vocational and two-year technical levels. To accomplish this goal, a cooperative study with industry in one state or province from each country was initiated. These include 1) Tasmania, Australia, 2) British Columbia, Canada and 3) Alaska, United States. Over one hundred mineral exploration companies and private consultants cooperated in the study by providing information regarding their specific training needs for support personnel, the data gathered has been used to identify training area for semi-skilled, skilled and technical personnel in geophysics, including, but not limited to, geo-logical skills, geophysical skills, surveying skills, environ-mental skills, and computer skills. With areas of major educational need defined for geophysical exploration, an educational field skills model has been developed for the three levels of training. The depth of each level of education and the training objectives for the work force at each level will he discussed.

Jan 1, 1992