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By C. M. Diaz, S. W. Marcuson

In the late 19th century, the discovery of rich nickel-copper sulfide ore bodies in Sudbury and the need for tonnage quantities of the metal to be used in nickel steel armor provided the foundation for establishing the Canadian nickel industry. For almost 50 years, International Nickel was the key player. In 1930, Falconbridge Nickel entered the field. These two companies remain the key Canadian nickel producers. This paper discusses the factors that have influenced the evolution of nickel smelting processes. The initial Sudbury ore smelting and nickel copper separation technologies were imported from abroad. It was only in 1937 that International Nickel established a process research laboratory in Copper Cliff The explosive post WW II industrial development created a strong demand for a broader variety of nickel products. For both International Nickel and Falconbridge, R&D became an essential business tool to succeed in the new market scenery. In the last few decades, new technologies were developed and commercialized to respond to the raising cost of energy, society pressing environmental concerns, the advent of nickel laterites as an important source of new metal, the incorporation of new nickel producers to the market, and, therefore, the need to increase productivity. Canada thus became an important exporter of technology. In this paper, the authors review this history with the objective of highlighting the forces that have triggered the most important changes in Canadian nickel smelting.

Jan 1, 2005

By A. J. Reed, W. R. Bergey, Carr. J. M.

"The Highmont copper-molybdenum deposits are at Gnawed Mountain in the Highland Valley porphyry copper district, 125 miles northeast of Vancouver. This district is near the center of the lower Jurassic Guichon Batholith, where a north-trending swarm of porphyry dikes is crossed by west-northwesterly structural belts in which fracturing, intrusion of porphyry and breccia, and mineralization areconcentrated.The Highmont deposits are 2 miles southeast of, and in the same southernmost structural belt as, the Lornex deposit. The main deposits occur on either side of a composite dike of granodiorite, porphyry and breccia which strikes west-northwestward in fractured quartz diorite. North of the dike, the adjacent Nos. 1 (East) and 2 (West) zones together contain 150 million tons of open-pit ore mineable in two separate pits. These two zones will support a 25,000-tpd mill with a grade in the first five years of approximately 0.46 per cent copper equivalent. South of the dike, the Nos. 3 and 4 zones are partly explored and will provide large additional reserves. In these various zones, chalcopyrite, bornite and molybdenite form disseminations and fracture-fillings accompanied by quartz, K-feldspar, tourmaline, sericite, specular hematite and other minerals. Bornite extends for varying distances north of the dike, beyond which chalcopyrite is locally accompanied by pyrite. Higher-grade mineralization tends to coincide with fracture swarms, or with shear zones and faults which largely parallel these swarms. The ore zones are reflected by geochemical soil anomalies which show some glacial dispersion. LP. surveys gave weak but significant responses, expressed as per cent frequency effect. The ore zones occur within a strong magnetic gradient, but do not show a significant magnetic response."

Jan 1, 1971

By H. V. Kinsey

"IntroductionTITANIUM is probably the most widely publicized metal today. Much has been written, both in the lay press and the technical press, about its properties and potentialities. In view of the fact that Canada possesses large quantities of titanium-bearing ore, and could conceivably become a major producer of metallic titanium, it was felt that a paper dealing mainly with the physical metallurgy of titanium would be of interest to this Institute. This paper is concerned chiefly with the useful properties of titanium and its alloys and the fundamentals governing the modification of its properties by alloying.Physical Properties of TitaniumTitanium belongs to a family of metals that have been termed 'gas sensitive' (I), because their mechanical properties are altered by certain gases which they readily absorb and retain. Other metals of this group are zirconium, hafnium, vanadium, columbium, tantalum, and chromium. Titanium has a strong affinity for oxygen and nitrogen and once it has absorbed these gases they cannot be removed either by melting in vacuum or by any degassing agent. These gases, when present in excess of about half a per cent oxygen plus nitrogen, render the metal brittle and useless as a structural material.Some of the typical physical properties of titanium are listed in Table I along with those of common structural metals for comparison."

Jan 1, 1953

"IntroductionThe Chairman, in his speech to this body last year in Montreal, stated that the Dominion Coal Board looked to and depended upon the Bureau of Statistics for statistical material, and the Bureau does collect and publish monthly and annual data on coal. It may therefore be asked why an officer of the Dominion Coal Board should prepare and give a talk on statistics.I would explain that it has been our experience in the Board that, since the supply and consumption of coal in Canada is subject to a seasonal ebb and flow, it can be more profitably studied on the basis of a twelve-month period ending on March 31st than of a calendar year, since the end of March does represent a fairly stable end point in this ebb and flow. The figures are not prepared or published by the Bureau on that basis and it has therefore been thought that a presentation on this fiscal-year period would be of interest. The Bureau of Statistics has agreed that this may be valuable and all the data here presented are based on the reports secured from various sources by the Mining, Metallurgical and Chemical Division, Dominion Bureau of Statistics. The only contribution by either myself or the staff of the Dominion Coal Board has been the tabulation in a different twelve month period, and the comments upon the picture presented.It should be noted that the data for the month of March, 1950, are not available in all cases and consequently the figures for that year contain an estimate for this month."

Jan 1, 1950

By R. P. van Hille, A. W. van Zyl

The BIOX® culture, aiding liberation of arsenopyrite/pyrite occluded gold, is inhibited by thiocyanate (SCN > 1 mg/L); precluding the recycling of tailings water up-stream of the bioleaching circuit. The activated sludge tailings effluent remediation (ASTERTM) process is a biological process that was developed to facilitate water recovery and treat waste water on-site (to achieve a SCN concentration < 1 mg/L) to be recycled or disposed of. The aim of this study was to investigate the effects of changing temperature and SCN loading on the SCN degradation ability of the mixed microbial population clue to seasonal temperature changes and fluctuations of SCN concentration in the waste water.

Jan 1, 2011

By S. K. Schwartz

"This paper describes the general layout of the environmental monitoring scheme at Devco &apos;s No. 26 Colliery, including wall face ventilation, fan performance and methane drainage, and then goes on to discuss the sensors, the outstation layout, the surf ace control room and the protection of the system.IntroductionCape Breton coal mines have been pioneers in the use of the latest technology in mining coal on this continent. To mention just one example, continuous methane monitoring at the coal face was started in 1976 and the idea of automatically stopping the face conveyor during high gas levels using the face signalling system was conceived and developed by CBDC engineers.With the introduction of remote environmental monitoring, No. 26 Colliery will be the first underground coal mine in Canada and possibly in North America to have computer-based comprehensive environmental monitoring.Traditionally, surveillance of the mine environment has been based mainly on periodic checks by portable or hand-held monitors. Although this method proved adequate, it has some limitations, namely:1) restricted &apos;number of observations and samples;2) relatively long time between taking measurements and availability of results for assessment.With remote monitoring, the above limitations are overcome because (a) monitoring is continuous and (b) monitored data are updated quickly (typically 5-7 sec.). Remote monitoring also provides a centralized &apos;information center&apos; at the surface from where the entire mine environment can be monitored. Details of modes in which data can be displayed and features available at the location will be discussed later in the paper."

Jan 1, 1982

By John H. Low

Introduction Despite the fact that the .association of magnetite with chrysotile asbestos in the parent producing area of the world, the Thetford Mines - Black Lake area, has been recognized since the ores of that region were first known, magnetic methods were not extensively employed in exploration for asbestos until about the beginning of 1949. Since then, large areas of Ontario, Quebec, and the eastern United States have been prospected both by aeromagnetic and conventional ground magnetic methods. Prior to 1949, a limited amount of magnetic work had been done, notably that of A.H. Miller (1, pp. 184-186), which was carried out in conjunction with the geological survey of the Thetford area by H. C. Cooke (2) in the years of 1930 to 1932. At that time, Miller pointed out that the occurrence of asbestos is associated with very large magnetic &apos;anomalies&apos; and that, within the Pennington dyke, an area of asbestos- bearing peridotite could be distinguished, by the anomalies, from adjacent areas of non-asbestos ?-bearing peridotite. Since he .also observed large anomalies in what were believed to be ?barren areas, Miller concluded, however, that the magnetometer could hardly be of much or any value in the direct location of asbestos War .and post-war demands on known reserves of asbestos ore, however, stimulated the search for new deposits, and an economical and rapid method of directing speculative drilling was most desirable.

Jan 1, 1951

By J. T. Kalala

The High Pressure Grinding Roll (HPGR) is gaining acceptance in the mineral processing industry and has become a competitive technology in reducing the specific energy consumption in Mineral processing plants. The amount of samples required for HPGR amenability testwork and HPGR wear tests is usually high and often cannot be available at early stage of projects were only a few drill cores are available. Although HPGR was initiated from small scale piston die compression tests, the development of small scale piston die test to predict the performance of HPGR has been slow. The objectives of this paper was to present the designs, operating procedure of piston-die press and operating conditions which have resulted in similar particle size distribution obtained from a piston die test and HPGR Labwal unit starting from the same feed size distribution. Testwork were conducted using a 2 MN piston-die press and a Labwal HPGR unit on major South African ore types, viz, gold, platinum and iron ores. The results obtained show that piston-die test can generate data to predict energy consumption, product size distribution, and even to evaluate the edge effect.

Jan 1, 2012

By J. A. Brown, F. P. Kerr, M. A. Archer

Extensive testwork on Global Atomic’s Dasa Project in Niger has been conducted at SGS Minerals laboratory in Lakefield, Ontario. Much of this testwork has focused on a two-stage counter-current leach as a means of improving leach efficiency and decreasing reagent consumption. The ore contains uranium mineralization requiring relatively high sulphuric acid concentrations during leaching to achieve acceptably high extractions. Excess free acidity in the leach solution may be utilized by recycling the high acid solution and contacting it with fresh ground ore. The resulting pregnant leach solution (PLS), now higher in uranium concentration and depleted in free acid, is forwarded on to uranium recovery by solvent extraction. The first stage residue proceeds to the second stage leach where fresh acid and oxidant are provided to leach the remaining uranium. This paper presents the results of the testwork conducted on both a Master Composite and Variability samples.

Jan 1, 2020

By P. deH. Eastcott

The paper summarizes a slide presentation made during the CIM Mechanical-Electrical Operators&apos; Conference, held at Sudbury. Ontario, January 25-27, 1977. Its scope has been limited to a few specific aspects of modern Canadian hoisting plant practice that are likely to be of interest to operating personnel. It is intended to serve as a brief review of established methods discuss in more detail the present state-of-the-art and suggest trends that will appear as products during the next few years.

Jan 1, 1977

By W. D. Mulholland

"I ASSUME that any effort on my part to deal with the question of the importance of the mining industry is going to be largely an exercise in preaching to the converted, but there are one or two aspects that I'd like to particularly mention.The first is that, in terms of almost all factors, the mining industry is a very important industry in Canada. It is important in terms of employment in relation to the gross national product of Canada and it is particularly important in the international trade of Canada. So far from being insignificant domestically, it is also an extremely important factor in the international picture. That's an important point to bear in mind, because as we talk about all the other matters we never can lose sight of the fact that mining management always has to be conscious of its international competitive position. It is something that one forgets at one's peril, and to a somewhat greater extent than is true of many other industries, those managements have to compete in an international context for their markets, to some extent for their people for specialized skills and of course for finance. In the evolution of domestic policies it is a very, very perilous step to take to impair that competitive ability of the domestic mining industry."

Jan 1, 1972

By W. P. Campbell

Foreword At the outset, it should be stated that this paper does not pretend to present a panacea for the ills that &apos;frozen&apos; wells are heir to, but rather is an attempt to bring to the attention of those whose special concern it is, a little theory and some facts, which have been brought to light recently, in connection with the problem of &apos;freezing&apos; as it applies to naphtha-producing wells in the Turner Valley field, and to draw some conclusions that follow from the facts discovered. It should also be stated that the investigation is not to be regarded as in any sense complete, but in progress. Doubtless new facts will be brought to light from time to time which may modify present ideas on the subject, but whether favourable or contrary, these will be welcomed, as the purpose of the Department is to secure as complete information as possible of the factors contributing to &apos;freezing&apos;, since this must be the first step to an intelligent attempt to remedy or prevent its occurrence, if such can be done. It is possible, too, that the cause or causes of freezing may not be the same in all cases, but whether this be so or not will have to be determined later as new information comes to hand. Introduction One of the worries which must constantly confront the operators of gas-naphtha producing wells in Turner Valley-although all, fortunately, have not met with it-is the possibility of the occurrence of what is commonly called &apos;freezing&apos; (going off production).

Jan 1, 1930

By K. Muehlenbachs, J. U. Stemler

"Abstract - The Boston deposit is a recently discovered Archean lode-gold deposit located approximately 700 km northeast of Yellowknife, in the southern portion of the Hope Bay volcanic belt. Primary H2O-CO2-NaCl fluid inclusions associated with gold mineralization at Boston are of low salinity (4.6 ± 1.4 eq. wt.% NaCl, n = 182) and contain pure CO2. Homogenization temperatures of liquid-phase inclusions average 270° ± 33°C (n = 141), but some fluid inclusion assemblages contain coexisting liquid- and vapor-phase inclusions that homogenize near critical conditions, suggesting phase separation. In these groups, liquid-phase inclusions homogenized at 299° ± 25°C (n = 24), and vapor-phase inclusions homogenized at 338° ± 28°C (n = 18). These temperatures overlap within error, and a median temperature of ~320°C is taken as representative of trapping conditions within the veins. An approximate pressure of 2-3 kbar was estimated from fluid inclusion isochores at this temperature. Stable isotopic compositions of carbonate minerals from the mineralized zones range from -4.7‰ to -3.1‰ in d13C, and from 11.2‰ to 12.8‰ in d18O; quartz ranges from d18O = 12.8‰ to 14.9‰; and pyrite ranges from d34S = 2.1‰ to 3.5‰. The d18OH2O, d13CCO2, and d34SH2S values of the fluid calculated from these minerals at 320°C are 6‰-9‰, -2.4‰ ± 0.6‰, and 1.5‰ ± 0.5‰, respectively, and are intermediate between metamorphic and magmatic compositions. A unique source for the fluids cannot, therefore, be constrained from these data. Petrographic and geochemical data for the Boston deposit are consistent with data from other Archean lode-gold deposits worldwide, implying that the Boston deposit formed in a similar environment and from similar types of fluids. These results suggest that the Hope Bay volcanic belt may represent a major new mesothermal gold belt in this part of Nunavut. Sommaire - Le gîte Boston a été récemment découvert à environ 700 km au nord-est de Yellowknife dans la partie sud de la ceinture volcanique de Hope Bay, il s’agit d’un gîte d’or filonien d’âge Archéen. Les inclusions fluides primaires de H2O-CO2-NaCl associées à la minéralisation aurifère du gîte Boston présentent une faible salinité (4.6 ± 1.4 eq. pds.% NaCl, n = 182) et contiennent du CO2 pur. La température d’homogénéisation des inclusions à phase liquide est en moyenne de 270° ± 33°C (n = 141), mais certains assemblages d’inclusions contiennent des phases liquides et gazeuses coexistantes qui s’homogénéisent dans des conditions quasi critiques, suggérant qu’elles résultent d’une séparation de phase. Dans ces groupes, les inclusions de phase liquide s’homogénéisent à 299° ± 25°C (n = 24) et les inclusions de phase gazeuse s’homogénéisent à 338° ± 28°C (n = 18). Ces températures se recoupent à l’intérieur des limites de l&apos;erreur de mesure, et nous considérons qu’une température médiane de ~320°C est représentative des conditions de piégeage dans ces veines. Les isochores permettent d’estimer une pression d’environ 2-3 kbar à cette température. La composition des isotopes stables des carbonates dans les zones minéralisées s’étend de -4.7‰ to -3.1‰ pour d13C et pour de 11.2‰ à 12.8‰ pour d18O; les valeurs de d18O pour le quartz varient de 12.8‰ à 14.9; et les valeurs de d34S dans la pyrite vont de 2.1‰ à 3.5‰. Les valeurs de d18OH2O, d13CCO2, et d34SH2S du fluide calculé à partir de ces minéraux à une température de 320°C est de 6-9‰, -2.4‰ ± 0.6‰, et 1.5‰ ± 0.5‰ respectivement, reflétant des conditions intermédiaires entre des compositions métamorphiques et magmatiques. Il n’est donc pas possible d’identifier une source unique pour ces fluides à partir de ces données. Les données pétrographiques et géochimiques du gîte Boston sont similaires à celles d’autres gîtes d’or filoniens ailleurs dans le monde, ce qui implique que le gîte Boston s’est formé dans un environnement similaire à partir des mêmes types de fluides. Ces résultats suggèrent que la ceinture volcanique de Hope"

Jan 1, 2006

By Z. F. Zhou, X. Y. Zhou, V. G. Papangelakis, Z. D. Jankovic, S. M. Ulyanov, S. N. Lvov

Recently developed flow-through electrochemical techniques (1,2) were employed for measuring pH in high concentration aqueous solutions and geothermal brines. The pH values of (1) 5.0 mol kg-1 NaCl + x mol kg-1 HCl, (2) 3.0 mol kg-1 of NaCl + 0.5 mol kg -1 of KCl + 1.0 mol kg-1 of CaCl2 + x mol kg-1 HCl (x < 0.1 mol kg-1), and (3) mixtures of Al2(SO4)3-H2SO4-H2O, MgSO4-H2SO4-H2O, and NiSO4-H2SO4-H2O solutions have been measured at temperatures from 100 to 280°C. The obtained experimental data and their thermodynamic analysis demonstrated that the electrochemical system can be used for on-line pH monitoring of high concentration aqueous solutions with an accuracy of ±0.1-0.3 pH units over a wide range of temperatures. Greater deviation exists in real laterite leach solution measurements due to in situ precipitation of Na-alunite. The system is excellent for research and process development work. Further work is needed to ensure robust operation under pressure leach conditions of laterites.

Jan 1, 2004

By G. K. Lee, E. R. Mitchell

Designers of combustion processes may select aerodynamic conditions which produce only superfine fly ash. Although it is not usually anticipated that this will create a problem, such as has been found to agglomerate in high-velocity gas streams, to plug mechanical dust separators in a short time, and to contribute to atmospheric pollution. The problem is a fundamental one, and may be approached in several ways. The authors, in the course of their combustion research program, had occasion to examine the agglomeration of ash, ranging from sub-micron to 17 microns in size, produced in a (coal and oil) dual-fuel-fired steam generator. Several theories, supported by extensive laboratory studies, have provided some understanding of a probable mechanism of agglomeration. As a result, certain precautions are suggested in the design and selection of combustion processes and equipment.

Jan 1, 1962

By Y. M. Shneerson, V. M/ Shpaer, E. E. Zhmarin, A. Y. Lapin, E. M. Vigdorchik

This paper describes studies of zinc concentrate oxidizing pressure leaching using the method of mathematical modeling. The concept of a kinetic function was taken as a basis for mathematical modeling of the leaching process. The kinetic function describes dependence of the unreacted component share OJ on the relative time x (the relative time is the ratio of the test duration and the time of complete dissolution). This kinetic function is determined in accordance with the results of batch laboratory tests. The laboratory tests have been carried out on zinc concentrate produced from Kazakhstan zinc-copper ores. Zinc concentrate consisted mainly of three types of minerals: sphalerite (70%), pyrite (13%) and chalcopyrite (10%). Oxidation reactions of sphalerite, pyrite and chalcopyrite have been considered as principal ones. The kinetic characteristics of the process (kinetic function, reaction order, activation energy, duration of complete dissolution of the concentrate components) have been calculated in the course of laboratory tests. The mathematical model was used for estimation of the main technological leaching process parameters (such as process rate, degree of metals extraction, autoclave capacity, heat balance, etc.). Mathematical modeling based on the kinetic function concept allows safe designing of metallurgical equipment and scaling the technology to industrial capacity.

Jan 1, 2004

By E. G. Charlesworth, M. J. Robertson

"Abstract - Gold mineralization in the Main Reef Complex at Sheba Gold Mine is hosted within shear zones in a sequence of shales and greywackes of the Fig Tree Group. Competency contrasts between these rocks and a steeply dipping chert unit provided a locus for the development of right lateral steeply dipping shear zones. A set of flatter dipping shear fractures crosscut these zones with their intersections defining a system of en échelon ore shoots.Mineralization is both of vein type and disseminated strata-controlled replacement type. The latter occurs mainly within the wall rocks to the shear zones. Arsenopyrite and pyrite are the major sulfides, with arsenopyrite being confined largely to greywacke beds and pyrite to the more iron-rich shale units. Gold was introduced, together with minor sphalerite, pyrrhotite, chalcopyrite and early arsenopyrite, toward the end stages of a first pyrite phase. The mineralizing fluids were introduced along dilated cleavage planes and, emanating from these, produced a series of replacement fronts. Mineralization was syntectonic to late tectonic and occurred under conditions of progressive deformation, resulting in sulfides which are concentrated in the hinges of shear-related folds and semi­ massive sulfides within tension fractures which are folded, attenuated and fractured .An analysis of the structures shows a sequence of events in which an initial ductile simple-shear event with a steep sense of movement was succeeded by a more brittle strike-slip event. Mineralization is temporally related to the latter. This evolution in structural style was probably related to reactivation of the Sheba Fault as a transcurrent fault during emplacement of large granitoid bodies."

Jan 1, 1994

By Paul R. Clark

Outline ? Coal As An Energy Resource ? Canadian Clean Power Coalition ? Phase I of the CCPC Project ? CO2 capture options ? Gasification ? CO2 use ? Results ? Phase II Plans ? Next Steps TransAlta - Profile ? 9,726 megawatts (MW) of capacity ? 46,877 gigawatt hours (GWh) produced at an average plant availability of 88.4% ? 47 facilities in four geographies: Canada; the U.S.; Mexico; and Australia ? Fuel mix of coal (62%), gas (26%), hydro and renewables (12%) ? 23.2 million tonnes of coal mined ? 47.0 million gigajoules (GJ) of gas consumed

May 1, 2004

By Penny C. Stewart

Narrow vein underground stope design engineers in Australia have expressed significant interest in the requirements and methodology for developing site-specific stability charts. This is largely due to a concern that existing stope stability charts inadequately take into account factors influencing narrow vein stope stability, such as the effect of backfill abutments and the effect of in stope pillars. This paper presents conclusions from a comprehensive statistical examination of case history requirements for a site specific stability chart and critiques literature arguments for site-specific charts. A new statistical analysis technique and a large comprehensive stability database enabled the authors to quantify case history requirements and any site-specific effects the model exhibits. The analyses indicated that a reliable stable-failure boundary requires at least 150 case histories, of which a minimum of 10 percent should be unstable stope surfaces. Marginal site-specific effects were observed for the operating conditions captured within the database. The authors conclude that the apparent site-specific effects noted in previous literature are attributable to operating conditions inadequately represented in the database. Such operating conditions could induce erroneous stability predictions at any site, and are therefore not truly site-specific. Following from these conclusions, a strategy for taking into account operating conditions particularly relevant to narrow vein mining has been proposed. In particular, the development of a chart that accounts for the effect of backfill abutments on stope stability. Backfill abutment effects are particularly relevant to mechanised narrow vein mining methods such as modified Avoca. Collaboration from at least five sites is required to obtain access to relevant data and underground drives for geotechnical mapping. Preliminary estimations indicate that approximately three months fieldwork is required to meet case history requirements. CMS data in conjunction with 3-dimensional design software will be used to calculate equivalent linear overbreak/slough (ELOS). In contrast to stable, failure, major failure and caving categorical variables, ELOS is an objective and continuous stability variable and is therefore, more conducive to mathematical modelling.

Oct 1, 2001

By A. F. Banfield

"IntroductionELEMENTAL sulphur occurs in three types of deposits: in salt domes in the Gulf Coast region of the United States and Mexico, from which over 90 per cent of world native-sulphur production is obtained; in sedimentary deposits such as those in Sicily, which are thought by some authorities to contain the largest world reserves of elemental sulphur; and as surface deposits, associated now or in the past with some phase of vulcanism, the type which bas the greatest world-wide distribution.Deposits of the volcanic type are the subject of this paper.From antiquity until the successful development of the sulphur-bearing salt domes at the beginning of this century, important sulphur production for local needs was obtained from volcanic deposits in many parts of the world. Due to technical and economic factors, however, producers could not compete in price with sulphur from salt domes. •The result has been that, except in Japan and Chile, little sulphur was produced from volcanic deposits from about 1910 until the start of the Korean war in 1950. Shortly after the outbreak of the Korean war, an acute world sulphur shortage developed and prices skyrocketed in many countries up to several hundred dollars a ton. Interest in volcanic deposits was renewed and exploitation of many was undertaken. Few of these operations have been successful, mostly due to inability of management to solve technical problems.While important volcanic deposits of elemental sulphur have not been reported ( 1) in Canada, and it is doubtful that any will be found, data presented in this paper may be of interest to students of ore genesis.This paper is based on field examination of numerous deposits of the volcanic type in North and South America."

Jan 1, 1954