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By Zara Hosseini

?Microseismicity ?Seismic Systems ?Intrinsically Safe and Explosion Proof Seismic System ?Case studies: ?Gas Drainage Optimization ?Fault Identification ?Conclusion Seismic Event ?Occurrences in which energy is released in the rockmass creating a series of seismic waves propagating throughout the rockmass ?Can cause a Fall of Ground or CoalBurst Factors creating Seismicity: ?Mining at Depth ?High stress zones ?Major geological structures ?Mining practices and strategies ?Mining activities i.e. drilling and blasting

Aug 1, 2013

By M. A. Power

The diamondiferous Drybones Bay kimberlite pipe is the largest pipe (900 m by 400 m) discovered to date in the Northwest Territories. The pipe intrudes granodiorite of the Archean age Defeat Pluton and contains crater, reworked crater (epiclastic) and diatreme facies kimberlite. In-situ measurements of seismic p-wave velocity were recorded with in-line refraction arrays over representative areas. Refractions from fresh kimberlite were recorded over epiclastic facies kimberlite in the eastern portion of the pipe and returned an average velocity of 4300 m/s. Refractions from weathered kimberlite were recorded on all lines and returned velocities ranging from 1900 m/s to 2200 m/s. Granite surrounding the pipe returned an average velocity of 5400 m/s. The results indicate that there is a definite contrast in seismic velocities between kimberlite and country rocks at Drybones Bay and suggest that seismic refraction surveys may be an effective means of screening kimberlite targets in glaciated areas underlain by igneous or metamorphic rocks.

Jan 1, 1998

By J. P. Mogan, E. D. Dainty, K. Katsuyama

"The Volvo BM 861 U articulated truck is one of the few underground diesel units manufactured by an organization which shares the same corporate roof as the engine manufacturer. As a consequence, the unit has provided an opportunity for the characteristics of the entire system- turbocharged aftercooled engine, transmission and exhaust scrubber- to interact to minimize emission levels. The performance of the components of the system, as evaluated by full-scale dynamometer testing, is summarized. The over-all effect of the various innovations was a 38% reduction in the recommended ventilation level over that of the bare engine.IntroductionThe Mining Research Laboratories of Energy, Mines and Resources Canada is required, as part o f the certification service of the Canadian Explosive Atmosphere s Laboratory, to test the exhaust emissions of diesel engines, and to recommend appropriate amounts of fresh ventilating air to minimize the risks to health of underground personnel working with, or in the vicinity of, such diesel engines. Volvo BM AB of Sweden made application for the certification of the BM 861 U truck during a period in which EMR personnel were engaged in a number of research projects concerned with improving the environment in dieselized mines. One such avenue of research was the venturi or high-energy scrubber; as the BM 861 U was equipped with this type of scrubber , EMR and Volvo BM agreed to cooperate in a considerably more extensive investigation than would be normal for a certification application. The outcome of some of this research is summarized in this paper."

Jan 1, 1981

By J. G. A. Stevenson

GENERAL Location of Property THE Stirling zinc-lead-copper deposit is in Richmond county, Cape Breton, about a quarter of a mile southwest from Stirling P.O., and some 45 miles southwest from Sydney. The property is accessible by road for at least nine months of the year, and during the navigation period coastal boats maintain a service touching at the port of Fourchu, eleven miles from the mine. When flying conditions permit, the Cape Breton Flying Club, of Sydney, will carry passengers to or from the property, a service which has been particularly advantageous on two occasions when hospitalization was urgently required. The Company has mining rights on leases Nos. 73-74, 78-80, and 101-104, inclusive, and owns 166 acres at Stirling and one acre at Fourchu. The ore deposit is in lease No. 73. History The Stirling deposit was discovered in the 'nineties', probably about 1895. The original discovery is said to have been made in the bed of Copper creek, which traverses the ore-zone. For a number of years, indifferent development work was carried on with a view to copper production only, and it was not until1915-16 that attention was directed to the possible production of zinc. Previously, the ore had been considered too complex for metallurgical treatment. During the period 1916-24 several operators attempted to develop the property, among them being the Stirling Exploration Company, Stirling Mining & Smelting Company, New Jersey Zinc Company of New York, Hayden & Stone Company of Boston, and The Eastern Mining & Milling Company. Up to 1924, the work was limited mainly to trenching, stripping, ? diamond drilling, and shot drilling.

Jan 1, 1937

By C. M. Campbell

The Inconceivable Wealth propaganda goes on apace. Premier King, at Vancouver, has stated that we still have, untouched, natural resources, "beyond the wildest dreams." Principal Currie, in an address before the Canadian Society in New York said that Canada's resources, "are as yet merely scratched and it is not possible to compute her almost fabulous natural wealth." Mr. Meighen, in the last election campaign announced that, "under the providence of God, Canada is more richly endowed, perhaps, than any other country in the world." Four years ago a despatch was sent to Premier King "on behalf of" this Institute advising him that "Inconceivable Wealth" in minerals in this country was assured. This was made as a statement ~f "incontrovertible fact." Specifically, this despatch stated that this wealth was on such a scale that the mining industry would in the future lead all others in this country. This inventory is still in effect as far as this Institute is concerned.

Jan 1, 1926

By R. S. Bigelow

Part 1.- Metal Mines Early experiments with mechanical loaders in metal mines were confined largely to machines of the shovelling type and generally air-operated. Although the first application of the scraper to metal mines dates back to 1910, it was not until about twelve years ago that it came to be used extensively. Generally, the scraper gives better results in metal mines than in coal mines, as degradation due to soft bottom and breakage are not factors, but it has a wide range of application and is successfully used in the mining of salt, potash, gypsum, zinc, copper, and a variety of ores, from soft material to hard chunky ore which settles compactly. Today, the scraper has replaced to a large extent the shovelling type of machine in metal mines. Scrapers have offered an inexpensive solution for the mucking problem and are now employed in most mining districts throughout the world. They are operated by labourers of all colours and degrees of skill. Each installation, however, requires individual study on the part of the mine mechanical department to determine the type of scraper, horsepower of hoist, and most economical speed of rope, as well as method of rope rigging. Unfortunately, the scraper has no power to select pay ore from waste and its suitability for use under circumstances which might require sorting of the ore can only be decided by a weighing of the economic factors involved

Jan 1, 1931

By Andrew Kerr

Overview of Presentation ? Introduction ? An historical context: From 1866 to the 21st century. ? Geological framework for iron ore in the region known as the ?Labrador Trough?. ? Producing iron-ore deposits of the Labrador City ? Wabush area, and near-future production from the Schefferville area. ? Exploration projects representing potential future production?.or expansion of the district. ? Some concluding remarks???

May 1, 2011

By The Satff

"TEXADA Island is situated in the Strait of Georgia, about 100 miles northwest of Vancouver. The property of Texada Mines Ltd. lies on the southwest coast of the northern end of the Island. A part of the ""Sunshine Coast,"" the climate is moderate, with about 30 inches of rain during winter months and relatively dry summers. Texada has been shipping high-grade magnetite concentrate continuously since 1952 to Japanese ore buyers. In 1959, a 3,000-foot tunnel was driven just above sea level to explore the possible downward extension of known orebodies then being mined by open pit. In January of 1961, because the open-pit operations had a limited life, C. C. Huston and Associates were brought in as mining consultants to do a feasibility study on the possibility of going underground for production. This study was completed in March, 1961. With the completion of the report, the Company went to Japan seeking a ,long-term contract to justify the capital outlay necessary for setting up an underground operation. Concurrently, underground diamond drilling revealed more ore, and the Company planned some modifications to the concentrator for increasing the copper recovery. By November, 1961, a ten-year contract was signed with Japanese ore buyers for the sale of 450,-000 long tons of concentrates beginning in October, 1963. Since that time, the Company has built its own 65 000-ton ore carrier and an additional three-year contract has been negotiated, with an annual tonnage increase of from 450,000 to 550,000 tons."

Jan 1, 1967

By F. Chiesa

Experimental results on thin and thick castings poured in aluminum A356 and magnesium AZ91E by the low pressure permanent mold process have been compared to the result of filling simulations for thin and thick castings. If the results of modeling is reliable when the liquid remains above the liquidus temperature, this is no longer the case when partial solidification occurs. The visco-elastic behavior of a partially solidified liquid is difficult to put into equation as it depends on the amount of shear it has been been subjected to. Attempts to predict misruns with a commercial software has been proven to be very difficult if not impossible; divergence of the numerical solution has been observed unless prohibitively long computing times are used. In order to overcome these difficulties from a practical standpoint, a simple method is proposed which consists in tracking the temperature of the advancing liquid metal front so as to make sure it will always be above so-called `Misrun Critical Temperature' (MCT) determined experimentally for thin and thick aluminum A356 and magnesium AZ91E castings. If the liquid metal front falls below this temperature, a cold-shut or misrun is likely to happen at this location. The values of MCT for thin and thick in aluminum A356 and magnesium AZ91E were determined experimentally on misrun castings of extreme geometries (a thin 2.5 mm wall cover and a 6mm to 25 mm thick bell housing). MCT was found to be lower for magnesium AZ91E and for the thicker castings.

Jan 1, 2011

By C. Lambert

It has been shown that contacts between host rock and engineered barriers may be critical in the design of deep radioactive waste repositories. Water is expected to reach the interface zone after the re-saturation of the geological massive and its presence may lead to concrete leaching. Such a phenomenon could increase the interface transmissivity and compromise the confinement of radioactive waste. Recent experimental results from Buzzi et al. (2008) have enhanced how concrete leaching can drastically change the mechanical behaviour of such interfaces. Because of the local loss of strength resulting from leaching, shearing resulted in a degradation of the interface asperities. Similarly to rock joints, intact interfaces exhibit a usual contracting-dilating behaviour. On the contrary, depending on the extent of leaching, the degraded interface can display a fully contracting. This paper intends to investigate the influence of concrete leaching on the mechanical behaviour of host rock-concrete interfaces. The leaching process consists in the dissolution of some of the hydrates of the cement paste, leading to a reduction of the strength and Young's modulus. A discrete model has been developed with PFC3D where a simplified interface morphology has been introduced using a saw-tooth description of the asperities.

May 1, 2009

By H. Miki, S. Wheatley

The addition of precipitated silica greatly enhances chalcopyrite leaching in the presence of sodium chloride at moderate temperatures (65-90°C) in acid media with ferric ions as the oxidant. The beneficial effect increases with the increase in chloride concentration and temperature. The addition of sodium silicate and silica sand has no significant influence. The analysis of solubility data in acid/salt solutions indicates that the solubility of silica as Si(OH)4 as the dissolved species is controlled by the activity of water, as expected from the hydration theory. Kinetic analysis shows the trends that copper dissolution from chalcopyrite in the presence of precipitated silica with sodium chloride follows a shrinking sphere model indicating a chemically controlled surface reaction. The effect of temperature on copper dissolution in the presence of both precipitated silica and sodium chloride was also larger compared to the results in sodium chloride alone. The SEM analysis shows that chloride and silica facilitates the precipitation of sulfur on the surface of the silica particles rather than the chalcopyrite particles which avoids the blockage of the mineral surface and thus improves the leaching kinetics.

Jan 1, 2014

By Forrest A. Kerr

Introduction During recent years the work of the Geological Survey in northwestern British Columbia has been in the nature of reconnaissance and exploratory mapping, largely for the purpose of gaining knowledge of the potential mineral-producing zones known to occur along the eastern side of the Coast range, and also to gather such data as might facilitate their exploitation. Commencing with fairly detailed mapping in the more accessible parts, the work has been continued and expanded until now an understanding has been gained of the more general features of a continuous section along the range for a distance of about two hundred miles. Geographically, northern British Columbia is more or less isolated. It is cut off from the central part of the Province by a rugged and mountainous country which, except for the telegraph line and a rarely travelled trail along it, is not penetrated by any developed routes or lines of communication. To the west, it is cut off from the Pacific by the Coast range, an extremely rugged area sixty to eighty miles in width which, except along the few navigable rivers cutting across it, cannot be readily traversed. Politically, it is further isolated in this direction by the narrow strip of south-eastern Alaska which borders the coast and extends inland to the axis of the range.

Jan 1, 1931

By K. Lascelles

ABSTRACT Nickel compounds vary significantly in their toxicological properties, so it is critical that continuing studies to accurately quantify worker exposures consider the processing that accompanies refining nickel-containing materials. The Clydach nickel refinery, which has operated for more than 100 years, was the first nickel-producing facility to show a high risk for lung and nasal-sinus cancers among workers employed since it opened in 1902. Process chemistry and equipment have changed dramatically over Clydach’s history. This paper describes the processing evolution at Clydach with a focus on the propensity for aerosol formation and the forms of nickel in airborne dusts.

Jan 1, 2013

By G. P. Gu, B. Fang, R. W. Revie, M. Elboujdaini

Stress-corrosion cracking (SCC) tests were conducted in the near-neutral pH standard solution, NS4, and in an actual soil solution, using four-point bending at high a stress ratio and low frequency conditions very similar to those of operational pipelines. Pitting incubation appeared first and then pitting initiated and grew in both solutions although there were many more pits on the specimen tested in soil purged with 5% CO2 + 95% N2 than in the specimen tested in NS4 solution purged with the same gas. These observations show that samples in soil solution are more susceptible to pitting than those in NS4 solution. When the pit reached a critical size, the increased stress concentration around the pits, resulted in the transition to a crack.

Jan 1, 2005

By D. A. Jacobson

Mining operations, whether new or existing, are constantly looking for ways to maximize production and improve energy efficiency, while keeping the footprint required to a minimum. The Nordberg MP1250 cone crusher was designed with these three goals in mind. A series of side-by-side evaluations comparing an MP1250 to an MP1000 were completed at two Freeport-McMoRan operations. The first evaluation began October 2009 in a tertiary position and the second began March 2010 in a secondary position, where it remains in full production today. Utilizing 25% higher power capacity than the existing MP1000 tertiary crushers, the MP1250 had 29% higher capacity and 17% lower specific energy, adjusted for differences in feed and product size. The MP1250 compared to the existing MP1000 secondary crushers achieved 30% higher capacity at a slightly reduced specific energy, while achieving a finer product. The MP1250?s higher capacity and energy efficiency may have application in many crushing plants. Depending on site specific economic factors, greenfield projects may benefit from a smaller footprint and less ancillary equipment, whereas brownfield projects may benefit from higher capacity or a finer product within the same footprint.

Jan 1, 2012

By E. V. Konopleva, H. J. McQueen

Steels in high variety have been providing strength and ductility for more than a century mainly through complex heat treatments following hot shaping. The economical and sustainable goal was a steel with the two operations combined through applying knowledge of dislocations and strengthening mechanisms aided by new mechanical and microstructural techniques. Primary hot reversing-mill rolling produced static recrystallization (SRX) between every pass to significantly finer grain size. Hot torsion showed that with lay-on temperature and rate of reduction suited to gradual precipitation of minor additions of Nb, the austenite grains would become highly pancaked; the existence of very fine subgrains along the grain boundaries (GB) could be deduced from tests on stainless austenite. The HSLA strip had to be water-jet cooled immediately to prevent SRX at austenite GB and ensuring complete transformation to ferrite avoiding grain growth after coiling. Confirmation on old mills and successful product led to the design of more flexible mills for wider range of compositions and products. A significant one was auto bumpers that reduced crash damage. More crack-resisting compositions were developed for strip welding into line pipe for arctic oil transport. Lower metal consumption and easier fabrication has resulted in more sustainable welded bridging.

Jan 1, 2015

By R. H. McCorkell

Radon emanation rates. J. and compositions of materials from the Canadian Certified Reference Materials Project (CCRMP) indicate that the fraction of the Rn produced that escapes, E, is usually 1% to 8% and the 238U decay chain is nearly in secular equilibrium. For some Chinese ore standards, E values are higher than f or the CCRMP materials. Standard ore tailings have 2/oPb concentrations higher than expected from their 226Ra concentrations and Rn escape rates (12 - 34%) . Biological materials have E ˜100%, their ash E ˜0%. Pelletizing ore powders at 20 000 lb/in2 reduces J by only 20 - 40% but only 2% of Rn escapes from pressed Li2B4O7 pellets and 0.01 - 0.04% from fused Na2B4O7 or Li2B4O7 discs. Large, difficult-to-explain random variations in J are observed in some situations but several highly reproducible ways of measuring emanation rates have been found.

Jan 1, 1986

By E. C. Payne

"IntroductionTHE SMALLER industrial and commercial steam generating plants in the United States are suffering from an ‘engineering deficiency' which, if allowed to continue, will probably result in the extinction of the species• that now burn •approximately 75 million tons of coal. We will classify as 'small' those plants which should require not more than one operating man per shift, including those in which as little .as thirty minutes per day should be adequate for .all service attention. These are the small steam plants that need the most, and get the least, expert attention for fuel :planning, equipment selection, design layout, .and proper operating technique. Dissatisfaction with bituminous coal is usually caused by one or more preventable weaknesses such as excessive or burdensome labour •for firing, .coal or ash handling and manual operation, smoke and fly ash emission above nuisance levels:, high maintenance and premium coal application for acceptable operation, and .finally, overall steam costs which are not .competitive. These 'deficiencies', so .common in the small coal-fired steam plants, can be readily eliminated by competent engineering and modern equipment with automatic controls."

Jan 1, 1953

By J. E. Udd, L. P. Geldart, B. B. Dhar

"Solutions for the stress distributions around simulated underground openings have been limited to calculations of boundary stresses for simple openings in which the boundaries may be expressed in mathematical terms. Studies involving circles, ellipses and ovaloids are re-ported in the literature.The stresses on the boundary of an opening and those at a distance from it in the medium are of concern to the engineer. The former may be related to the greatest concentrations of stresses encountered; the latter have a bearing on the identification of the ""zone of influence"" of the opening.Recent advances, in the form of a derivation for the stresses at a distance from an opening of elliptical shape, together with a solution derived previously for stresses in depth around ovaloidal openings, have been combined with computer programming techniques to provide complete solutions for a wide range of cases and variables. Some typical results which, it is hoped, may have some application to the design of underground openings are given herein."

Jan 1, 1970

By N. Dahata

Earlier research has indicated that an addition of titanium master alloy to aluminum alloys, results in improved fillability, grain refinement and finer pores. B206 alloy differs from other alloys used in automotive industry, with lower titanium level. This paper examines the effect of alloy chemistry (copper and titanium levels) and grain refinement (A1-5`)oTi- 1%B grain refiner) on grain size, microstructure and microporosity in B206 aluminum alloy. In this study, characterization of grain size, microstructure and microporosity was carried out using light optical microscopy (LOM) and scanning electron microscopy (SEM). Results have shown that the addition of 0.05 wt % titanium resulted in grain refinement of B206 alloy. With an increase in titanium to 0.25 wt further grain refinement, much reduced pore size and uniform distribution of pores resulted. These results suggest that B206 with proper addition of titanium has a promise as an alloy for automotive casting.

Jan 1, 2007