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By John C. Luck Jr.

"DEVELOPMENT of oil emulsion mud dates back to the early days of rotary drilling when oil was added to the drilling mud solely for the purpose of freeing stuck drill pipe. After the drill pipe was freed, and drilling resumed, this oil was considered a contaminant. Efforts were made to remove the oil but some of it remained and was emulsified with the drilling mud, thus forming a mechanical emulsion.During the late 1930's, operators found that adding crude oil to drilling muds seemed to alleviate 'sticky-hole' problems and so oil was allowed to remain in the mud. This practice was adopted when it was found that faster drilling rates and longer bit life were obtained. These observations led to the development of emulsion drilling muds. During the past five years their application has become more widespread because of the lower fluid losses obtained, greater lubrication qualities, faster penetration rates, and generally better hole conditions.An emulsion may be defined as a two-phase system consisting of a mixture of either finely divided oil droplets in water or of finely divided water droplets in oil. The surrounding liquid is known as the continuous phase. The emulsifiers reduce the interfacial tension, making the droplets tend to repel each other so that they remain dispersed and stabilized. These emulsions are classified as oil-in-water or as water-in-oil, depending upon whether water or oil, respectively, is the continuous phase. Briefly, close inspection shows that they consist essentially of globules of• the one liquid suspended in a continuous mass of the other liquid. Oil emulsion muds are usually of the oil-in-water type. Two basic types of emulsifiers •commonly used in Canadian muds are soaps and lignites."

Jan 1, 1954

By A. P. LeBis

This article attempts to relate the concept of utility to the risk involved when only a small number of projects (compared to their probability of occurrence) are accessible to a firm and to quantify utility when other financial and physical parameters are known.

Jan 1, 1978

By P. Nelson

Extending the campaign life of the Mitsubishi furnaces at Xstrata Copper's Kidd Metallurgical Division Copper Smelter has been a major focus of attention for many years. One aspect of this effort is real time monitoring to detect abnormal conditions and safely shut the furnaces down before significant damage occurs. Traditional real time methods of monitoring the integrity of refractory furnaces containing molten metal include alarms on individual temperatures of the refractory or cooling water. The need to set alarm limits which are not exceeded across the range of normal operating conditions leads to a system that only provides a limited warning, if any, before a failure occurs. Integrity monitoring systems that look at many different signals and alarm only changes in the relationships between the signals have been implemented on the smelting and converting furnaces. The systems are based on principle components analysis (PCA) models and implemented with the monitorMV software package. These provide much more sensitive and selective alarms so that changes in integrity are alarmed well in advance of any event. At a critical alarm level, the converting furnace is set to automatically shut down so that operating and technical personnel can review the situation. The configuration of the systems and operating experience with them will be discussed.

Jan 1, 2007

By Tim Robinson, Michael S. Moats, William G. Davenport, Andreas Filzwieser, Andreas Siegmund, Shijie Wang

This survey continues the long tradition of providing a snapshot of operating data from industrial electrorefineries. It is a supplement to previous surveys that were performed in 1987, 1991, 1995, 1999, 2001, 2003, 2007, 2010, 2013 and 2016. Analyses of current data and historical trends are presented. Examples of innovations to reduce costs, improve productivity, and improve quality are provided. In general, refineries continue to increase productivity while treating anodes with more impurities. INTRODUCTION This manuscript analyzes global survey data provided by operating copper electrorefineries. This paper continues a series of surveys of copper refining tankhouses that started in 1987 (Schloen, 1987, 1991; Schloen & Davemport, 1995; Davenport et al., 1999; Robinson et al., 2003; Moats et al., 2007, 2013, 2016). In this installment, data collected from 2015 and 2018 will be presented and analyzed. The 2015 survey data were presented at Copper 2016 in Kobe, Japan. This survey will continue the analysis of previous data to illustrate long term trends in copper electrorefining, which were originally presented at the Davenport Symposium in October, 2014 (Moats, Robinson, & Wang, 2014). Refineries who supplied surveys are listed in Table 1. Cathode production data from 2015 and 2017/18 (from surveys presented in 2016 and 2019) are provided to indicate which plants provided surveys and when. This manuscript presents operating data for ~6.5 million tonnes of copper production, which represents 30–35% of the world’s copper electrorefining production. The detailed survey results are available upon request from the corresponding author.

Jan 1, 2019

By J. M. Wolverton

CONSIDERABLE interest has always been taken in Safety-First and First Aid at the Sullivan mine. Even during the early days of development, Safety-First committees periodically held meetings, while lectures in first aid were given to any employees interested in the work. In 1929, a Safety Department was organized, and all accident-prevention and first-aid work was put in charge of a full-time Safety Engineer. An extensive programme has gradually been developed, the value of which can best be indicated by the reduction of the accident rate from 18.4 shifts lost per 1,000 shifts worked for non-fatal accidents and two fatalities for 1927, to 3.24 shifts lost per 1,000 shifts worked and no fatalities for 1936. SUPERVISION All work connected with accident prevention or first aid is under the jurisdiction of a central committee, known as the Accident Prevention Committee, which meets regularly once a month. It consists of all superintendents, department heads, foremen, and shift bosses, and is presided over by the Safety Engineer. At these meetings, the accident records of the previous month are reviewed and all accidents carefully analyzed and discussed. All proposed changes in the safety rules or in the accident tprevention programme are taken up and passed upon. Complaints or suggestions from the Safety-First Committee and the Employees Co-operative Committee, dealing with safety, are discussed and passed upon or a subcommittee is appointed to investigate and take any action found advisable. The question of underground ventilation and dust control, which recently has become a very important problem, always receives considerable attention.

Jan 1, 1937

By Roberto Pena, Cristhian Morales, Darwin Morales, Veronica Cambiaso

"This article makes evident the shortcomings of the current operation of oxygen pipes as well as the damages they cause and why they cause them. When focusing on the causes and effects of these drawbacks, it was possible to develop a new family of thermal lances that could pierce a taphole with the precision of a drill but with the capacity to complete the whole operation. Although efforts have been made to replace oxygen pipes since they are annoying, dangerous and inefficient, nobody had worked to improve the way the traditional oxygen pipe taps/perforates the furnaces and reactors tapholes. In fact, developments made in drills and robotic arms, have failed to replace the oxygen pipe, which despite their negative side effects have been used for more than a century. Observation and theory were key to radically transform this humble tool into a dependable and efficient support in the operation. A good news that it is worthwhile to share for the benefit of all of us, passionate about the world of pyro metallurgy.INTRODUCTION Normally, reports and papers prepared for conventions, symposia or other technical events related to metallurgy aim to relevant topics in the operational field, probably because in them lay the scale economies every company pursues. We intend to give relevance to a matter normally disregarded in operations, but that unmistakably vital: if the furnace or reactor cannot be bled, the pyrometallurgical process will not be completed. Besides, if the tapping task is difficult or is long delayed, the availability of the furnace will be reduced. Consequently, there will be a waste of energy and workers will be exposed to dangerous levels of radiation as well as to work overload and physical injuries Apart from these basic effects, in tapping operations where oxygen pipes are used, we can see serious damages in the smelting furnace, especially in the taphole components such as refractory bricks, taphole jackets and water cooled plates. This paper intends to show that taking care of the tapping task can significantly upgrade not only to the tapping operation itself, but also the whole plant productivity."

Jan 1, 2017

By L. H. Chen, Y. C. Chen, Leo Benyamin, W. C. Chen

"To investigate the evolution of fluid-driven fracture of rock-like material subjected to borehole fluid pressure and its consequential damage with regard to post-peak stabilization, micro-seismic activities have been monitored using nondestructive technique of acoustic emission (AE) corresponding to the macro-scale complete history of loading curve by setting the hollow cylindrical external circumferential strain to be a closed-loop feedback signal during servo-fluid-driven tests. Development of a novel fluidinduced loading system injected from internal borehole as well as monitoring system were equipped such that the initiation and propagation of micro-cracks enable to analyze experimentally. By programming/controlling either injection rate or fluid pressure, synthetic sandstones with low-permeability made by cement mortar were conducted in this study. It found that both the growth of macro-crack initialized intensively as reaching the breakdown pressure and the micro-seismic activities represented by AE locations show nice agreement. The experimental results in this paper provide better understandings of fluid-driven fracture mechanism.INTRODUCTIONFluid-driven fracture is a process of generating cracks by injecting viscous fluid into solid material. Conventionally, fluid-driven fracture tests have been performed by mining industry to measure the in situ stress (Haimson & Fairhurst, 1969) and fluid-driven fracture has been employed by the petroleum industry to recover oil and gas. Additionally, the mechanism of crack growth or the extension of existing cracks is important to the evolution of volcanic dikes over distances of a few kilometers (Lister & Kerr, 1991; Rubin, 1995), crack propagation in dams (Bolzon & Cocchetti, 2003) and the disposal of radioactive waste (Sun, 1969)."

Jan 1, 2015

By Yi Yang, Mark Zoback

"We report laboratory studies of the time-dependent deformation of core samples from four different formations in the Williston Basin - the Lodgepole formation, the Middle and Lower Bakken formations and Three Forks formation. The laboratory tests reveal varying amounts of viscoplastic deformation in response to applied differential stress. The time-dependent deformation is generally greater in rocks with higher clay and organic content, and can be described by a power-law function. Because the magnitude of the creep strain is linearly proportional to the applied differential stress, we can utilize viscoelastic theory and geophysical logs to estimate the degree to which tectonic stress is affected by viscoplastic stress relaxation. We suggest that viscoplastic stress relaxation results in the Upper and Lower Bakken Formations act as frac barriers during hydraulic fracture stimulation in the Middle Bakken, but the Lodgepole and the Three Forks Formations are not frac barriers.INTRODUCTIONHorizontal drilling and multi-stage hydraulic fracturing in shale reservoirs are critical for successful exploitation of ultra-low permeability shale gas, tight gas and shale oil reservoirs. Characterization of the mechanical properties of the reservoir rocks is essential to understanding the behavior of rocks during drilling and completion. Previous laboratory studies have shown that the timedependent deformation in clay-rich shales can be characterized as linear/viscoelastic deformation (Chang et al., 1997; Hagin and Zoback, 2004a, b; Sone and Zoback, 2013b, 2013c). Sone and Zoback (2013c) showed that laboratory measurements of time-dependent deformation in various gas shale reservoir rocks, and demonstrated that the viscoplastic deformation of these rocks can be characterized by a power-law function. They interpreted the results in the framework of linear viscoelastic theory to quantitatively assess the geomechanical effect of viscous time-dependent deformation over engineering and geological time scales. (Sone and Zoback, 2014) further extended the theory and proposed a viscous relaxation model that can be applied to predict the continuous differential stress magnitude using the geophysical logs. They tested the validity of their model by comparing the stress prediction with the occurrence of drilling induced tensile fractures (DITFs) and the vertical hydraulic fracture penetration observed from microseismicity."

Jan 1, 2015

By P. K. Gummer

Gold was fir t di covered on the Seabee property in 1947 by the Con olidated Mining and Smelting Company Limited. Acquired by Claude Resource Inc. in 1984, the property is now being explored by Placer Development Ltd . in joint venture with Claude Re ources. Between Augu t, 1985 and March, 1986, Placer completed 54 drill holes, extending the main o. 2 and o. 5 vein y tern to a depth of 1000 feet below surface and di covering two new satellitic gold zone 800 feet west of the o. 5 gold zone. Drill proven and probable geological re erve in four zone ( os. 2, 5, II, 14) to a vertical depth of 1000 feet, are approximately 1,120.000 tons averaging 0.32 oz. Au/ton.

Jan 1, 1986

By T. W. Cavers

The Dwight-Lloyd sintering machine was the answer to the flue-dust problem of the copper blast-furnace smelter. Then came concentration by flotation, which threatened to eliminate the blast furnace from the smelting field altogether, and again the sintering process solved the problem. As is well known, the sintering process is dual in its function; it expels sulphur from the charge and it converts a powdery material into nodules or chunks that hold together. The charge is ignited on top just as it passes over the edge of the first suction box, and the oxygen of the air that is drawn downward through the charge breaks up the sulphide and oxidizes about fifty percent of the sulphur. The heat produced by this reaction in the upper stratum of the charge ignites that lying immediately below, and, when the pallett has travelled the full length of the machine, the tire has reached the graces and the fine concentrate has changed its characteristics by being partially fused and has become a more or less solid mass. When the Granby Company was smelting its ore as mined, one small D-L machine was adequate for the treatment of the flue dust, but as soon as the policy of smelting the concentrate was adopted, it became necessary to add two large machines to the sintering plant. The three sintering units, of which two are 42 in. by 396 in. and the other 42 in . by 264 in. in hearth area, have a combined capacity of from 370 to 450 tons (dry) of charge per day. The capacity varies directly as the hearth area. The sinter produced is about 88 per cent of the dry charge, or 325 to 400 tons per day. The sintered fines returned for resintering average between 30 and 35 per cent of the charge, but this is not as great a disadvantage as might appear, since the addition of hot fines improves the burning qualities of the mixture. From 50 to 54 per cent of the sulphur is eliminated in the sintering operation.

Jan 1, 1934

By T. Scully

Since early days in coal mining, it has been known that some coals and the carbonaceous materials associated with them will heat and fire spontaneously. Many theories have been advanced to account for this phenomenon, but it is only within comparatively recent years that any scientific research has been carried out to determine the causes of this heating, the conditions which bring about its occurrence, and the reason why different coals heat with a varying degree of readiness. So far, this research has not cleared up these points entirely, but a great advance has been made in our knowledge of the matter. In general, any coal will fire spontaneously, although with a varying degree of readiness, provided conditions for its doing so are favourable enough. These conditions are that the coal must be in a fine state of division, that sufficient oxygen must be present for rapid oxidation, and that the air current passing must be so small that it is insufficient to carry off the heat produced by this oxidation. Many other minor factors, however, contribute to bring about spontaneous heating, either by producing initial heat themselves or by inducing the other major conditions.

Jan 1, 1931

By C. Yanqui

"Discontinuum Mechanics is based on two foundations: the idealization of the internal structure of substances, and the principle of the arithmetic mean value. For a linear discontinuum, the methods of Crystallography are used to describe their structure, in which nodes stands for the position of the homologous points such as molecules, grains, or any other motif. The principle of the mean value states that the value of any discrete function at a node is equal to the arithmetic average of the values of this function at the neighboring nodes. This principle leads to an elliptical linear differential equation of the second order, with coefficients given by the statistical second moments of the Cartesian components of the metric vector. As long as those coefficients are components of a symmetric second-order tensor, there are three mutually perpendicular directions, in which the variances reach their extreme values and the covariances are zero, showing that the mean value principle transforms the discontinuum into a statistically equivalent orthotropic continuum.The application of Discontinuum Mechanics to linear rock masses is simple and direct. It is sufficient to define the motif as the plane of geological discontinuity, and the metric vector as the normal vector to this plane, whose magnitude is the spacing between two consecutive planes belonging to the same set of discontinuities. Furthermore, heterogeneities of rock masses can be also included in this description by substituting the plane of discontinuity by a zone of weakness. In this way, the magnitude of the normal vector results from the product of the spacing and the RQD or the RMR. In going further in this theory, at least three conclusions show up. First, in the evaluation of rock masses, it is necessary to determine the orientation, spacing, and RMR for each set of discontinuities. Second, the conventional method of finding the principal families from the contours of equal concentration of poles on the stereographic projection excluding the spacing does not have any physical meaning. Third, any problem of rock mechanics can be solved in a rigorous and reliable way by integrating the differential equation of the mean value."

Jan 1, 2015

By S. Steinlechner, G. Schneeberger, J. Antrekowitsch

Due to always getting stricter environmental legislations as well as increasing land filling fees the efforts for treating residues from metallurgy are continuously increasing. In case of filter dusts from metallurgical industry, the high zinc bearing electric arc furnace (EAF) dusts or also dusts from secondary copper industry are important sources for the recovery of secondary zinc oxide. Because of low capacities for secondary zinc concentrates (like Waelz oxide) in primary zinc metallurgy, the upgrade of such concentrates to a quality that meets the requirements of high quality (technical) zinc oxide becomes more and more important. This would open the opportunity to break into new markets and use it for example directly in electrolytic galvanizing. Therefore this paper will summarize possibilities for an elimination of halogens from secondary zinc oxides. Furthermore selective volatilization trials, with a synthetic mixture according to the analysis of Waelz oxide, were carried out to remove impurities to achieve an upgraded product quality.

Jan 1, 2011

By G. A. Gross

Nearly 90 per cent of the iron ore produced in Canada is derived from iron-formation or bedded iron deposits. About 70 per cent of this consists of concentrates obtained fom iron-formation; another 20 per cent was formed by natural enrichment processes. Four principal varieties of iron-formation are recognized -the Algoma, Superior, Clinton and Minette types. Differences in their geology, mineralogy, chemical composition and environment of deposition are of special significance in their evaluation as ore.

Feb 1, 1966

By John R. Sullivan, Real Daigneault, Mathieu Piché, Jayanta Guha, Gilles Bouchard

"RESUMELa stratigraphie du camp minier de Matagami se résume a la présence de deux groupes volcaniques: le Groupe du Lac Watson et le Groupe de Wabassee qui le surmonte. Les gisements de sulfures massifs volcanogènes sont situés au sommet du Groupe du Lac Watson. Ces roches sont déformées par l'anticlinal de Galinée dont l'axe, orienté E-W, plonge vers l'ouest. Le cœur de cette structure est occupé par le Complexe de la Rivière Bell.Les roches volcaniques du flanc sud de l'anticlinal sont peu déformées et pendent à 45° vers le sud. Les gites qui s'y trouvent présentent la morphologie typique des gisements de sulfures massifs volcanogènes. Ceux-ci se situent le long d'un horizon repère cherteux et sulfure, appelé ""Tuffite Clef', et leurs cheminées d'altération rejoignent, en profondeur, une zone d'altération stratiforme d'étendue régionale.Les roches du flanc nord ont été transposées tectoniquement en écailles chevauchantes, de dimension kilométrique, a l'intérieur d'un couloir de failles anastomosées d'orientation est-ouest. A l'intérieur: le ce couloir, les gites de sulfures sont déformes et sépares de leur héminée d'altération sous-jacente par des failles.Les gites de sulfures situes sur les deux flancs de l'anticlinal de 'Galinée se seraient mis en place dans un mime environnement volcanique. Leur position stratigraphique est identique puisqu' ils se 'rouvent au sommet de la rhyolite porphyrique du Groupe du Lac Watson. lis se seraient constitués au cours d'une pose volcanique recédant 1'éruption du basalte du Groupe de Wabassee. Le Complexe de la Rivière Bell est perçu comme la source de chaleur responsable de la circulation des fluides hydrothermaux qui sont à ""origine des gisements de sulfures massifs volcanogènes."

Jan 1, 1990

By M. Ye. Shulgina, M. L. Bolotin, S. A. Prokopev, Ye. S. Prokopev

Iron ores concentration at Russia’s operations is carried out using conventional flow sheets. They comprise the two-four stage grinding followed by one-two stage magnetic separation. This results in the maximum recovery of magnetite to concentrate and the tailings generation. The final concentrate is generated only during the last stage of magnetic separation. Technologically, this flow sheet layout is not effective at recovering the liberated magnetite grains during grinding to the resulting concentrate. Advanced models of magnetic separators do not allow for the selective separation of the tailings and the portion of the resulting iron ore concentrate. Magnetic product which is the ore mixture of the liberated magnetite grains, high grade and low grade intergrowths is directed to the next grinding stage. In this case, regrinding of the liberated magnetite occurs. In addition, the performance of hydrocyclones during classification in closed grinding circuits is poor. Their classification efficiency does not provide the material separation in accordance with the size. In this case, simultaneous separation in accordance with the density occurs. The quartz particles with the size of 300 mm have similar velocity and trajectory like the particles of magnetite with the size of 60 mm. As a result, light and coarser intergrowths report to the overflow and free heavy magnetite grains report to underflow and return to regrinding (“the density effect”). This resulted in a significant increase of a mill circulating load, the decrease in the feed throughput and higher power consumption. In this connection, the development of iron ore concentrate stage recovery with the focus on gradual liberation of the intergrowths is getting much attention. Gravity concentration technique, particularly, spiral separation is effective at solving the problem of stage recovery not only the dump waste product but also high grade magnetite concentrates at the early concentration stages. This can be attributed to a significant difference in magnetite (4.9-5.2 g/cm3) and host minerals (quartz 2.7 g/cm3) densities, which is the principal during gravity concentration. The test work on concentration of various products samples from current operations (the mills discharges, concentrates from various stages of wet magnetic separation and cyclones underflows) was carried out. Spiral separators SV-500 and ShV-500 manufactured by Spirit LLC were used for the test work. High grade iron ore concentrate (69.05% Fe) was generated during primary wet magnetic separation concentrate concentration using a spiral separator. During the concentration of mills discharges the content of iron in the resulting concentrates and middlings of wet magnetic separation II stage was 64.5% and 64.6%, respectively. The recovery of iron to the concentrates of spiral separation was 33.6-42.0%. The studies presented demonstrate that by using spiral separation for iron-bearing ores concentration, you can separate magnetite liberated grains at the early concentration stages, decrease their regrinding and circulating loads in grinding circuits. This process is able to improve the overall recovery and economics of iron ores concentration process.

Jan 1, 2016

By M. Ye. Shulgina, M. L. Bolotin, S. A. Prokopev, Ye. S. Prokopev

Iron ores concentration at Russia’s operations is carried out using conventional flow sheets. They comprise the two-four stage grinding followed by one-two stage magnetic separation. This results in the maximum recovery of magnetite to concentrate and the tailings generation. The final concentrate is generated only during the last stage of magnetic separation. Technologically, this flow sheet layout is not effective at recovering the liberated magnetite grains during grinding to the resulting concentrate. Advanced models of magnetic separators do not allow for the selective separation of the tailings and the portion of the resulting iron ore concentrate. Magnetic product which is the ore mixture of the liberated magnetite grains, high grade and low grade intergrowths is directed to the next grinding stage. In this case, regrinding of the liberated magnetite occurs. In addition, the performance of hydrocyclones during classification in closed grinding circuits is poor. Their classification efficiency does not provide the material separation in accordance with the size. In this case, simultaneous separation in accordance with the density occurs. The quartz particles with the size of 300 mm have similar velocity and trajectory like the particles of magnetite with the size of 60 mm. As a result, light and coarser intergrowths report to the overflow and free heavy magnetite grains report to underflow and return to regrinding (“the density effect”). This resulted in a significant increase of a mill circulating load, the decrease in the feed throughput and higher power consumption. In this connection, the development of iron ore concentrate stage recovery with the focus on gradual liberation of the intergrowths is getting much attention. Gravity concentration technique, particularly, spiral separation is effective at solving the problem of stage recovery not only the dump waste product but also high grade magnetite concentrates at the early concentration stages. This can be attributed to a significant difference in magnetite (4.9-5.2 g/cm3) and host minerals (quartz 2.7 g/cm3) densities, which is the principal during gravity concentration. The test work on concentration of various products samples from current operations (the mills discharges, concentrates from various stages of wet magnetic separation and cyclones underflows) was carried out. Spiral separators SV- 500 and ShV-500 manufactured by Spirit LLC were used for the test work. High grade iron ore concentrate (69.05% Fe) was generated during primary wet magnetic separation concentrate concentration using a spiral separator. During the concentration of mills discharges the content of iron in the resulting concentrates and middlings of wet magnetic separation II stage was 64.5% and 64.6%, respectively. The recovery of iron to the concentrates of spiral separation was 33.6-42.0%. The studies presented demonstrate that by using spiral separation for iron-bearing ores concentration, you can separate magnetite liberated grains at the early concentration stages, decrease their regrinding and circulating loads in grinding circuits. This process is able to improve the overall recovery and economics of iron ores concentration process.

Jan 1, 2016

By Mike Smith, George Chung

"A 23 million dollar Flotation Plant has been commissioned at the Iron Ore Company of Canada in 1998. Nine OK-50 cells &re used to float silica in this 1,400 tomes per hour plant. The paper details project development, construction and operating results. This plant gives IOC the capability to produce not only high quality blast furnace pellets of varying silica, CaO and MgO levels, but also a high iron, DR grade pellet. The first activity was simply to sit down with the suppliers, Outokumpu, Wemco. GL&V and Svedala, to discuss applications and share experiences. We learnt what each supplier had to offer, what features would particularly suit this application, what options were offered, what were the materials of construction, how the equipment is maintained, which wear parts require replacement, etc., etc. We tried to learn as much about the equipment as the suppliers themselves knew. Then we tried to learn more: we contacted users and asked about any weak points, which options were worth incorporating and which items were not. We then discussed these points with the suppliers and established how potential problems might be overcome."

Jan 1, 1999

By T. L. Tanton

Introduction Sturgeon River area, on the east side of lake Nipigon, Ontario, was the scene of a gold rush in 1934. According to press reports, the active staking during the latter part of the summer spread out rapidly from the early holdings until it embraced practically all of the lower basin of Sturgeon river in a belt up to ten miles wide extending west from Kinghorn for 35 miles to lake Nipigon. And, before winter set in, active prospecting and claim staking reached beyond lake Nipigon to areas where belts of ancient schists were known, notably west of Obonga lake. The writer's familiarity in past years with the areas to which attention has been directed admits of some observations on means of access in the field, the general geology, and the progress that has been made in identifying formations favourable for the occurrence of gold. Canoe Routes From the writer's observations in Sturgeon River area in 1917 and in the Obonga Lake area in 1933, it is recalled that there is, locally, a striking dif~ ference in the accessibility of the two areas by travel along canoe routes. Sturgeon River area is easily accessible from Kinghorn or Jellicoe stations on the Canadian National railways. Many small lakes, commonly of the linear type and with elongations east and west, occur among the forested rocky ridges near Jellicoe (Figure 1) and to the east and west along, or adjacent to, Sturgeon river. This stream has long stretches with gentle current between the falls and rapids. The drainage system provides excellent canoe routes (Figure 2), and the interruptions to travel (Figure 3) are remembered .as scenic features that were passed by portages with firm footing. West of Obonga lake, the streams flowing easterly to lake Nipigon may be followed through scenic canyons to a plateau of law relief characterized by extensive muskegs and shallow, brown-water lakes; and along small streams, where beaver dams have been destroyed, there are muck ponds where the usual alternatives of paddling or portaging can be dismissed in favour of the 'moosing' method of progress with the canoe (Figure 4).

Jan 1, 1935

By Silvio E. Kruger

Real time measurement of wear and corrosion provides crucial information needed to determine an optimal schedule for corrective maintenance and is a powerful tool to maximise equipment availability and reliability. It also leads to savings from optimized spare parts handling and helps to avoid costs of accidents and their negative impact on safety and the environment. This paper presents the technology of ?painted-on? ultrasonic transducers that can be integrated to structures and accurately measure the remaining thickness and therefore determine wear or corrosion losses. These transducers have a small footprint, a performance comparable to other commercially available ultrasonic transducers and can sustain temperatures as high as 400ºC. The application of this technology to mining equipments and its potential benefits are discussed.

Aug 1, 2013