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By Royston Colbourne

Objectives Of Presentation - Identify specific risks - A fresh look at risk - Provide a moment reflection on risk - Open discussion on risk A route to solution and advanced thinking.

May 1, 2010

By Umbreen Agha, Stephan L. Chryssoulis, A. Margaritis

"The deportment of gold in samples of the biooxidation feed and product from the Harbour Lights mine in Western Australia was determined using optical microscopy and microbeam techniques such as Secondary Ion Mass Spectrometry (SIMS), Time-of-Flight Laser Ionization Mass Spectrometry (TOF-LIMS), and Electron Probe Microanalysis (EPMA). The main objective was to determine the mechanisms by which acidophilic bacteria (Thiobacillus ferrooxidans) liberate refractory gold which is locked in a sulphide minerals host as visible gold inclusions (> 0.1 µm) and as submicroscopic or 'invisible' gold.Using the integrated mineralogical approach approximately 99% and 100% of the assayed gold in the biooxidation feed and biooxidation product was accounted for. The results were compared to and verified by chemical assays.The gold deportment study indicates that during biooxidation, locked visible and 'invisible' gold is rendered cyanidable by the direct action of Thiobacillus ferrooxidans as well as indirect chemical leaching. Visible gold which is enclosed in sulphide minerals is liberated or partially exposed and is therefore rendered cyanidable as the host mineral is oxidized and dissolved. 'Invisible' gold either coalesces on the surface of the host sulphide mineral as the particle is dissolved or is released into the liquid phase and immediately adsorbs onto the surface of other ore particles with a net negative charge.The shakeflask suspension indicates that direct bacterial oxidation pits and channels correspond to zones of 'invisible' gold and arsenic (in pyrite) enrichment in the host sulphide mineral."

Jan 1, 1996

By Alan G. Galley

"Advances in our knowledge of the petrochemical attributes of deposit environments and of the character and extent of hydrothermal systems associated with certain deposit types has resulted in increased application of lithogeochemistry to exploration programs. Lithogeochemistry can be used to vector an exploration program toward an area of high potential through the use of a series of collapsing scales of analysis from a tectonic subprovince down to a particular stratigraphic segment. In the case of volcanogenic massive sulphide (VMS) deposits this involves the recognition ofsuitable volcanic domains, and the identification of subvolcanic intrusions and cogenetic felsic extrusive complexes. The recognition of chemical vectors within regional-scale alteration zones and associated chemical sedimentary rocks allows the geologist to identify the stratigraphic units with the most potential for hosting a base metal deposit.An integrated lithogeochemical program requires the judicious use of major, trace and rare-earth element and isotopic analysis. Standard discriminant plots may be employed to identify suitable tectonic and lithologic environments. Analysis of the chemical and mineralogical variations in broad-scale, semi-comfortable alteration zones provides a useful set of vectors to VMS mineralization. These may include contouring raw data, element ratios on XY plots, normalizing data against known rock values, or calculating mass changes in alteration zones."

Jan 1, 1995

By B. R. Neufeld, M. G. Heximer, S. J. Roach, W. G. Van Luven, D. G. Reynolds

"Teck Metals Ltd. operates an integrated zinc-lead complex at Trail, British Columbia, Canada. In the zinc plant, zinc concentrates are roasted to produce calcine, which is then processed in the leaching circuit for zinc recovery. Calcine is first dissolved at pH <2.0. This is followed by a precipitation stage using additional calcine that removes iron as a ferric hydroxide precipitate which is recycled to the lead operations. It is during this pH adjustment that impurities, notably arsenic, antimony and germanium, are co-precipitated with ferric hydroxide which is the primary removal phase for these elements. Recent processing conditions have resulted in lower iron inputs to the leaching circuit and this has resulted in insufficient co-precipitation of key impurities. This paper summarizes the influence of iron concentrations on impurity removal using laboratory and plant scale surveys, and emphasizes key specification limits for the primary iron removal circuit.INTRODUCTIONThe Sulphide Leach Plant (SLP) at Teck Metals Ltd., Trail Operations produces a zinc sulphate electrolyte from three different zinc bearing streams:1. Calcine, primarily containing zinc oxide, from the roasters2. Zinc electrolyte from the Oxide Leach Plant (OLP) is produced by leaching zinc oxide fume from the pyrometallurgical lead smelting operations3. Zinc slurry from the Zinc Pressure Leach (ZPL) autoclaveThe feed sources are blended and introduced to the iron removal process to precipitate iron in the form of a hydrolyzed iron precipitate which is recycled to the lead smelting operation. Along with iron, impurities, namely arsenic, antimony, germanium and silica, also co-precipitate; this process acts as the primary removal step for these elements. Following iron removal, the electrolyte is further processed in the zinc dust purification circuits. Cadmium and copper are removed in the cold stage circuit via zinc dust cementation, followed by cobalt cementation in the hot stage circuit."

Jan 1, 2016

By Jürgen Antrekowitsch, Gerardo R. F. Alvear Flores, Mehmet Ayhan, Christoph Zschiesche

Synergies between copper and lead extractive metallurgical processes enable the processing of a broad range of polymetallic materials. However, this complexity also brings some challenges expressed in terms of complex intermediates and final products. For instance, based on the limited solubility of Cu and Ni in crude lead bullion additional phases will appear during the crystallization of the melt. Beyond the need for continuous optimization of metallurgy the control of phase solidification is a further important pillar to achieve a more efficient process by minimizing the amount and cycles of reverts. This paper describes the microscopy study of one of the most relevant intermediate in the Cu and Pb metallurgy, the Cu based alloy and highlights the importance of applying a well-controlled cooling sequence to improve the overall process efficiency. INTRODUCTION One of the key aspects in Aurubis’s 2025 vision is to move towards the implementation of a multi metal recovery strategy. The implementation of this new multi metal vision is supported by the long tradition of the company, founded in 1866 as Norddeutsche Affinerie, and further developed by adopting modern copper smelting and lead smelting technologies for the processing of primary and secondary materials. The combination of these assets have already build the basis for processing of complex materials in the copper and lead circuits implemented in Aurubis’s facilities. The addition of a new smelting facility, will enhance these capabilities. Aurubis current flowsheet combines Cu, Pb and Zn metallurgy. This includes primary smelting of copper concentrate, processing of secondaries (residues, slimes, slags) and recycling materials (scrap, shredder material, e-scrap). These broad range of materials contain not only the mentioned base metals but also a number of minor metals that requires to be properly managed to ensure efficient recoveries and quality of the targeted metals.

Jan 1, 2019

By Peter Clevenstine

Minnesota Iron Ore Trifecta 1. World Demand 2. Industry Consolidation 3. Competitive Advantages

May 1, 2011

? A BARGE WILL BE INSTALLED IN THE BOTTOM OF A COMPLETED PIT. ? THE PROVEN BAUER CUTTER TECHNOLOGY WILL BE INSTALLED ON THE BARGE AND A DEWATERING PLANT WILL BE INSTALLED NEAR THE BASE OF THE PIT RAMP. ? THE WATER LEVEL IN THE PIT WILL BE RAISED BY 20- 40 METRES AND REMAIN CONSTANT OVER DURATION OF MINING. ? THE CUTTER WILL BE LOWERED TO MINE 10 METRE DEEP BENCHES ON A CHECKERBOARD PATTERN TO AN ULTIMATE DEPTH OF 200 METRES. ? THE 5? MINUS CUTTINGS WILL BE PUMPED TO THE DEWATERING PLANT, DEWATERED, AND TRUCKED TO SURFACE.

May 1, 2003

By C. Dodds, R. S. Ferrari-John, The University of Nottingham, G. Dimitrakis, J. Katrib, A. R. Batchelor

"Sorting technologies have the potential to reduce energy use in comminution by rejecting uneconomic ore before feed material enters the mill. However, a major challenge for sorting porphyry copper ores is providing a basis of discrimination between valuable and non-valuable fragments, due to their complex mineralogies and textural features. Microwave heating in combination with infra-red detection (MW-IR) has been shown to provide upgraded feedstock for certain ores at bench scale. Selective heating of copper sulphide minerals compared to the gangue leads to an increased thermal response for valuable fragments, providing the basis for sorting.Rapid scale up of MW-IR from bench scale to a 100 t/h continuous pilot plant facility has been facilitated by the design of microwave choking structures to allow continuous operation at industrially meaningful throughputs, whilst meeting health and safety and electromagnetic compliance standards, and the integration of materials handling with electromagnetic systems.Laboratory batch testing on a pilot scale microwave system has been undertaken to investigate the thermal response of copper ores under industrial conditions, at microwave energy inputs up to 1 kWh/t. These results provided the operating window and recommended test conditions for the continuous pilot plant. Sortability curves predicted in the laboratory are in good agreement with separations achieved during continuous pilot plant operations. The potential microwave sortability of a number of ores has been studied, allowing informed decisions to be made about potential ore candidates based on mineralogy. Future development of the technology will be underpinned by the creation and validation of scale up concepts for 1000 t/h operations. Understanding the value proposition for individual sites/applications will be central to unlocking the potential economic and environmental benefits of microwave sorting."

Jan 1, 2016

By Richard Dawson

Presentation Outline? Northeast BC Coal Fields Overview and History ?New mines and projects in development ?Design Issues for steeply dipping footwall slopes ?Design issues for angle-of-repose waste rock dumps

May 1, 2006

By H. Tudeshki

A great amount of aggregate is utilized in civil engineering applications such as road construction, railway infrastructure, concrete production, etc. Igneous rocks are the preferred raw material due to their high strength and abrasion resistance. Rock quality assurance is a key factor and has great influence on the quality of constructions in civil engineering. One of the major problems encountered by both the producers and users of igneous aggregate rock is the fact that, with the passage of time, some specific rocks lose their strength, up to a complete loss of structure, i.e. disintegrate and degrade. This phenomenon has a great influence on the quality, strength and durability of aggregates. In the last decades, different methods and procedures such as the glycol test, the methylene blue dye test, as well as the Los Angeles test, have been introduced to distinguish rock properties, and to identify these problems. However, as these wet-chemical methods are time consuming, hard to perform, only to be applied to hand-piece samples, requiring special laboratory equipments, and are only possible to be accomplished under laboratory conditions, their application has always been severely limited. To address this widespread quality management problem of the quarry industry, a relatively quick, easy and user-friendly approach is necessary. It calls for a systematic solution with a device that can simply be used in the day-to-day routine of a mine for quality control of the quarry´s daily production. Our research is concentrated on developing a systematic method for early recognition and diagnosis of rock quality, in order to control and manage the quality of the quarry production in advance. Our new approach is based on two rock parameters: magnetic susceptibility and loss on ignition. The measurement of these parameters provides reliable information on the quality of the rock and allows the quality control process to be accomplished and performed at the borehole location. Our new approach has been assessed through extensive field and laboratory studies and has been implemented on the drill-cuttings of a basaltic andesite quarry. The results of the experiments are discussed in detail, including their impact on increasing resources and environmental protection.

Aug 1, 2013

By S. Banisi, M. Pourkani, A. R. Laplante, A. Partoazar

"Canadian experience in industrial modeling of grinding, classification, and flotation kinetics was applied at the Sarcheshmeh copper mine, which processes 40,000 t/d of ore at 0.9 % Cu, in an effort to improve capacity and metallurgical performance. Mcivor's functional performance analysis was applied to ball mill cyclone circuits to maximize circuit capacity. Plitt's cyclone model was applied to predict how apex wear would affect classification performance, as part of a predictive maintenance program whereby the optimum wear period is determined for cast iron apexes. The flotation flowsheet was improved using Agar's optimization criteria. The impact of these technologies has been nothing short of spectacular, with an improved capacity of 1 S to 20""/o, and increased recoveries.1-IntroductionThe Sarcheshmeh copper ore body, which may rank as third or fourth largest in the world, contains 1 billion tonnes averaging 0.90 % copper and 0.03 % molybdenum. It is located southeast of Iran and has been processing 40,000 t/d of ore since 1982. The mine produces 100,000 tonnes of copper and 2,200 tonnes of molybdenum concentrate per year. After three stages of crushing, the ore with a Fso of 12. 7 mm is fed to 8 parallel ball mills in closed circuit with cyclones to produce a product 70""/o finer than 7 S microns. The concentrate of the first stage of flotation is reground and the tailings constitute the main component of the plant final tailings. A concentrate with an average grade of 31 % Cu is obtained after cleaning and re-cleaning stages. Total recovery of the plant varies between 83 and 87 % depending on the operating conditions and ore type.To improve the overall performance of the plant, it was first decided to evaluate the performance of grinding, classification and flotation. Measures were then taken to improve performance using the following criteria: (i) The improvements should be of the types that have resulted in significant improvements in other plants (e.g. Shannon et al, 1993); and (ii) The proposed improvements must be achievable with the manual operation presently used at Sarcheshmeh. The outcome of this study could also help in making decisions on the implementation of automatic control systems in the Sarcheshmeh copper mine."

Jan 1, 1998

By T. Crivits

"Phase equilibria in the ‘Cu2O’-‘Fe2O3’-SiO2 system, the base slag system in copper production, were recently determined. However, the addition of MgO, commonly present in the slag, drastically changes the phase equilibria in this system. The present study focuses on the phase equilibria in the ‘Cu2O’-‘Fe2O3’-MgO-SiO2 system in equilibrium with metallic copper.Recently, an experimental procedure has been developed that resolved a number of experimental difficulties. This procedure has been successfully applied to characterise several complex industrial copper slags. It includes a high-temperature equilibration followed by rapid quenching and electron probe X-ray micro-analysis (EPMA). The methodology was adapted to the present system and used to determine the liquidus at SiO2 saturation and in contact with high-MgO phases in between 1100 and 1250 °C in Cu2Orich slags.The results indicate a maximum solubility of MgO in the system at 1200 °C of 5 wt%. The boundary line between tridymite and spinel lies 3-4 wt% closer to the SiO2 apex for every 2 wt% MgO added. These new data on the high-copper slags are important for optimisation of the direct-to blister"

Jan 1, 2014

By I. B. Schalamuk, R. E. de Barrio, M. J. Pons, M. B. Franchini, L. Meinert

"Several Fe, Fe-Cu, and Cu-Ag prospects hosted by Mesozoic carbonate-rich sedimentary rocks that were intruded by diorite stocks define an approximately 20 × 200 km belt along the Andes Cordillera of southwest Mendoza province, Argentina (34°-36°S). This belt includes the Hierro Indio and Vegas Peladas Fe skarns, Las Choicas, and several other Cu-(Ag) prospects.The main features of the Fe skarns include: association with mantle-derived middle Miocene (~15-11 Ma) diorite stocks and sills; widespread alteration including epidote ± amphibole ± magnetite endoskarns, and zoned garnet (Grs0-66 Adr32.5-100) ± magnetite ± pyroxene (Di24-50 Jo2-9 Hd74-41) exoskarns formed from oxidized, saline, high-temperature brines (530º-660ºC; 60-70 wt.% NaCl equiv.); and magnetite-hematite orebodies associated with quartz ± epidote ± calcite ± actinolite formed at lower temperatures (290º-436ºC) from saline fluids (32-50 wt.% NaCl equiv.) of magmatic origin.West of the Fe skarn belt, the Valle Hermoso district covers more than 300 km2 and hosts several poorly known Cu-(Ag) prospects (estimated 30 Mt with 1.5% Cu and 20 g/t Ag). These prospects share many characteristics with the iron oxide copper-gold-type systems and manto-type Cu deposits of northern and central Chile. One of the prospects (Las Choicas) is located at the apex of a regional 015°-trending anticline, along the contact of stratified calcareous sandstone and limestone (Neocallovian-Oxfordian) with a diorite pluton. This pluton has positive Ta and Nb anomalies (on normalized diagrams) and a high Ti content, features uncommon in Miocene diorites associated with Fe skarns and of magmas derived from sub-arc mantle sources. Alteration at Las Choicas includes early widespread chlorite + calcite ± albite ± scapolite ± ilmenite or titanite ± apatite, and local actinolite ± hematite ± biotite alteration of diorite and sedimentary rocks along contacts. Later Cu mineralization (1%-10% Cu) is associated with calcite ± albite ± quartz alteration in fractures, vein networks, and crackle breccias. Mineralization is zoned from bornite ± chalcopyrite ± millerite with Zn, As, Mo, Ag, and U anomalies in the main orebody, through chalcopyrite-rich breccias with Zn anomalies, and chalcopyrite ± tetrahedrite vein networks with Sb, As, Ag, and Zn anomalies in the uppermost zone, to a Cu-depleted pyrite-rich envelope with Co anomalies, and finally to late, barren calcite veins in distal zones."

Jan 1, 2007

By R. J. Labine, D. I. Brisbin, R. Roussain, P. R. Coad

"Abstract - The Owl Creek Mine is located near the west end of the Neo-archean Abitibi greenstone belt, 17 km northeast of Timmins, Ontario, and 4 km north of the Destor Porcupine fault. Gold occurs in epigenetic quartz veins and their pyritic wallrocks in two zones within a package of east striking, steeply north dipping, volcanic and sedimentary rocks. At the West Zone, 1 729 603 t of ore with a grade of 4.83 g/t Au (268 587 troy oz.) were produced from an open pit centered on a wedgeshaped unit of Tisdale Group basalt that occurs between two overturned, south facing units of Porcupine Group graywacke and argillite. Basalt/graywacke contacts are locally marked by graphiticcarbonaceous argillite, strike-parallel faults and massive quartz veins.Deformed quartz+/-ankerite veins occur along the graphitic sedimentary/volcanic contacts and in gently to moderately dipping fractures in basalts, and, to a lesser extent, in graywackes. Veins also occur sub-parallel to steeply dipping 070° foliation. Altered host basalts are composed of iron carbonate, sericite, quartz, carbon, chlorite and disseminated pyrite. Gold occurs as inclusions in pyrite, and less commonly as free gold in fractures and along graphite-quartz grain boundaries in quartz veins. Fractures preferentially developed in more competent basalts during pre- to syn-ore deformation are interpreted to have provided the permeability required for emplacement of mineralized quartz veins. Carbonaceous basalt/graywacke contacts further enhanced gold deposition by acting as chemical traps. The interaction of hydrothermal fluids with these carbonaceous sedimentary rocks led to the characteristic local darkening of host basalts due to carbon impregnation and chlorite development."

Jan 1, 1998

By B. Galy, L. Giraud

"This paper compares Canadian provincial mining safety regulations regarding the use and testing of cage safety catches, including a brief history and evolution. Regulations are similar across provinces, with only slight variations. Currently, the “Ontario-type” safety dog is the most commonly used safety catch in Canada. Performance estimation of the compensation mechanism for different safety-dog shapes and tooth angles show this shape works well and has consistent braking results, but the best efficiency is obtained for initial tooth angles greater than 10°. Miner safety is questionable for lightly loaded cages, an issue that should be addressed technically and legislatively.RÉSUMÉ Le présent article compare les diverses réglementations de sécurité minière concernant les parachutes des cages dans les provinces canadiennes ainsi que les essais qu’ils doivent subir. Il semble que les réglementations soient semblables à travers les provinces avec quelques légères différences ou divergences. Un bref historique des parachutes et de leur évolution est présenté. De nos jours, le parachute de « type Ontario » est le plus fréquemment employé à travers le Canada et il présente des résultats de freinage uniformes. Une estimation de la performance du mécanisme de compensation pour les diverses formes de taquets de sécurité et les divers angles des dents montre que cette géométrie fonctionne bien; cependant, la meilleure efficacité est obtenue pour des angles de dents supérieurs à 10°. La sécurité des mineurs est mise en jeu pour des cages faiblement chargées et ce point devrait être traité du point de vue technique et du point de vue législatif."

Jan 1, 2016

By S. V. Ulianov, A. Y. Senchenko, A. A. Shvets, A. V. Aksenov

Development of an efficient technology to process complex ores containing gold and antimony as well as silver is described in the paper. The results from the testwork aimed at the valuables recovery by means of flotation are presented. A process sample of antimonite gold-bearing ore was studied in TOMS institute aiming at development of a technology to process such an ore with generation of antimony concentrate and sulphide gold-containing concentrate. Material composition study indicated that the ore included 5.3% of sulphides: arsenopyrite – 2.4%, pyrite -2.4%, and antimonite – 0.5%. Gold is present as an isomorphic dissemination in arsenopyrite. At sighter testing stage a direct selective flotation flowsheet was chosen to process the ore. Antimonite flotation was activated due to addition of lead nitrate. A single cleaning of a rougher flotation concentrate resulted in antinomy concentrate with 30% Sb content and 71% recovery. Au recovery into antimony concentrate did not exceed 1%. Sb flotation tailings were used to float the remaining sulphides and gold. The resulted sulphide concentrate was characterized by Au content of 20 g/t at about 80% recovery, arsenic content - 10% at ~80% recovery, and sulphur content - 18% at ~81% recovery. The sulphide concentrate can be forwarded to further processing aiming at gold recovery. Given that the concentrate is highly refractory it should be pretreated (bacterial or pressure oxidation, Albion process) prior to cyanidation in order to liberate gold from sulphides. The proposed technology allows one to solve the problem of precious metals recovery from antimonite ores.

Jan 1, 2016

By Lar Liljeblad

"As demands upon the earth&apos;s natural resources continue to grow, exploration companies, mining organizations and others face the problem of the need to tackle increasingly more difficult strata to open up new reserves. Innovations in materials technology and tool design have steadily improved this capability, but none perhaps so drastically as a recently introduced cemented carbide in which tool wear resistance and/or toughness can be tailored precisely to the user&apos;s drilling needs.Introduction Until about forty years ago, the bulk of rock-drilling operations had to be carried out with hardened steels. Short life between re-grinds was common especially in abrasive rock formations. Shortly after World War II, Sandvik, Sweden, pioneered the development of sintered (cemented) carbide-tipped steel tools as a means of improving drill tool life. The new material was a composite of tungsten carbide and cobalt, the latter acting as a &apos;cement&apos; to bind the wear-resistant carbide grains together, and the composite, in turn, was brazed to the steel. The immediate effect was a 100-fold increase in the service life of the tool.Intractable ProblemsWhile the carbide-tipped tools served the mining and quarrying industries admirably there were, nonetheless, some seemingly intractable limitations. The greater the wear resistance of the material - the quality for which it is selected - the more brittle it is. Also, rocks vary widely in hardness and abrasiveness and no single tool, either in terms of material or shape, meets every need. Specifically, for fast penetration of non-abrasive rock, toughness must be combined with a relatively sharp tool prome. Highly abrasive rock, on the other hand, demands a substantially broad area of extremely wear-resistant material on the tool if long bit life is to be assured. Between these extremes there are innumerable variations in rock"

Jan 1, 1991

By L. J. Bryson, C. A. Biley

"Anglo American Platinum’s Rustenburg Base Metals Refiners (RBMR) produces Ni and Cu cathode from slow cooled converter matte after Platinum Group Metals (PGMs) are magnetically separated for further processing. In 2010, execution of the RBMR expansion project was commenced to increase the production capacity to 33 ktpa Ni. The expansion, which is currently still in a ramp-up stage, brought about several fundamental changes to the circuit chemistry, including the installation of a dedicated Pressure Iron Removal (PIR) autoclave. This provided an independent outlet for iron from the refinery, which previously deported to the residue from the leach circuit and was toll refined. At the same time as changes in the circuit associated with the RBMR expansion were being made, the plant experienced a significant increase in iron and copper units per nickel unit in the feed. The decoupling of the leaching and iron removal process steps has had significant advantages for the robustness and control of the overall circuit, in particular pertaining to the preparation of a nickel electrolyte of sufficient purity to produce LME grade nickel. This paper details the primary changes to the RBMR circuit chemistry with a particular focus on iron deportment and the benefits derived from the installation of the PIR autoclave.INTRODUCTIONAnglo American Platinum mines and refines Platinum Group Metals (PGMs) through a complex processing pipeline in its South African operations. Mined ore is first treated through several mineral processing stages, geared to the recovery of base metals and associated PGMs, followed by smelting and refining operations that aim to separate base metals from PGMs and recover the value components to purified, saleable products. The focus of this paper is the Rustenburg Base Metals Refiners (RBMR) complex which receives a PGM-containing converter matte, then physically separates PGMs and base metals, and recovers nickel and copper to cathode by utilising leaching, precipitation and electrowinning processes.With new mining operations coming online and the continued increase in PGM ore arisings, it was necessary to undertake an expansion project at the Base Metal Refinery (BMR) to increase production capacity from 21 ktpa to 33 ktpa Ni. Complicating the expansion project was the requirement of continued production through all stages of design, construction and implementation and, due to stringent capital constraints, the utilisation of all existing equipment installed during a previous expansion in 1981. Against this backdrop, the expanded BMR flow sheet involved significant changes to the chemistry, especially iron management. These changes in iron management allowed for the separation of iron and copper residues and significantly increased the robustness of the plant to changes in feed mineralogy as well as the potential to increase production duties of the existing equipment."

Jan 1, 2016

By I. Lazaro Roche, J. Brunner, J. Busto, X. Martin, J. B. Decitre, S. Gaffet, F. Hivert

"Muon tomography allows investigating the subsurface. Muons being penetrative, the attenuation of the muon flux depends on the quantity of matter the particles travel through, hence on the rock density and thickness. For the Temporal Tomography of rock Density using Muon Measurements (T2DM2) project, the muon flux measurements are performed in LSBB URL (http://www.lsbb.eu) in order to study the hydrogeological processes in the unsaturated area of Fontaine-de-Vaucluse karst aquifer. The suitability of the muography for this study is here numerically demonstrated. In parallel to these simulations, muon flux measurements are carried out in the LSBB galleries by means of a set of four scintillator tanks and Micromegas detectors are developed. These detectors, here described, are adapted for underground and confined spaces as well as other environments. Their performances are particularly interesting and should contribute to the expansion of muon tomography in new application fields. INTRODUCTIONMuon tomography or muography is a method to image large volumes by measuring the absorption of cosmic ray muons. It uses, in a passive way, a natural radiation source: the muons which are charged particles produced in the atmosphere. Primary cosmic rays interact with atmospheric nuclei and produce a huge number of secondary particles, including muons. Due to their important mass compared to electrons, they are highly penetrating, reaching several hundreds of meters below the surface. Their attenuation depends on the quantity of matter they cross. That's why they are used to investigate the subsurface, muon absorption measurement allowing to estimate the in-situ density of the rock.Georges (Georges, 1955) proposed in 1955 to use the muons in order to study the density variations caused by the overburden over an Australian tunnel. In 1970, Alvarez (Alvarez, 1970) imaged the internal structure of Chephren Pyramid thanks to this method. The muon tomography has been particularly developed for volcanology (Nagamine, 1995; Tanaka, 2007; Lesparre, 2010; Carloganu, 2013) over the last twenty years. Since the beginning of the 2010's, a growing amount of projects that proposed to use the muons in various fields get underway: the CO2 storage (Kudryavtsev, 2012), the exploration of Mars (Kedar, 2013), etc."

Jan 1, 2015

By Rodney Allen

Background: Development of the Project ?European GEODE collaboration 1999: considers possible projects, including a VMS project, to continue after GEODE ?GEODE-CODES-Canada collaboration 1999: Questionaire, database ?Workshop at CODES 2000: project theme and strategy selected ?GEORANGE (Sweden-EU) 2001 supports development of Global VMS Project: interest from 12 nations ?Skellefte VMS Project set up as Sweden?s component of Global VMS, 2002; other projects in Spain, Canada collaborate ?Low metal prices ---> little funding from mining industry 2001-2003, change in strategy ?IGCP/UNESCO support 2004: enlargement to over 20 nations

Apr 1, 2005