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By C Dowding, C Aimone-Martin, P Abeel

This paper presents measurement and analysis of the dynamic response of a five-storey building to very high frequency excitation (>100 Hz) from blasting vibrations originating from a contiguous excavation of rock. Velocity response measurements in the rock and on the structure were employed to calculate the time-correlated dynamic displacement response of the building to blasting. Time-correlated structure response measurements are needed to advance the understanding of the response of urban structures to high-frequency excitation. Current regulations and understanding are based upon measurements of the response of one- to two-storey residential structures by 10 to 40 Hz excitation. The extension of these observations to taller structures when excited by high-frequency excitation needs to be investigated further.Measurements show that the amplification patterns at the ground level and top of the structure match or are lower than that observed by the US Bureau of Mines (Siskind et al, 1980) for the shorter residential structures. They decrease with increasing peak particle velocity. From the measurements, the global transverse shear strains found by differentiating ground floor and top displacements were calculated to be 12 µstrains. Time-correlated bottom and top of structure displacements show that building response may be more reflective of wave propagation up the structure than whole-structure inter-storey drift.In addition, a 3D model was used to compare computed displacements and strains to measured results. Modelled responses varied considerably, both in magnitude and location of the maximum strain. No conclusion can be made regarding the best 3D model to employ to simulate building response. More data such as motions measured at many points in the structure are needed. Maximum inter-storey transverse shear strains calculated with the model were found through the acceleration excitation and were less than 12 µstrains for 37 mm/s rock motion excitation. The inter-storey transverse shear strains calculated with rock displacement input were less than that found with the acceleration excitation.CITATION:Dowding, C, Aimone-Martin, C and Abeel, P, 2015. Measured and modelled response of a multistory, urban structure to high-frequency blasting excitation, in Proceedings 11th International Symposium on Rock Fragmentation by Blasting, pp 211–220 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 24, 2015

By Chung Yu, Wang

CHINA can he roughly divided into three metallogenetic province: North China, the Yangtze Valley, and South China. In North China the old Pre-Cambrian schists and gneisses are represented by the abundance of quartz mines in which sporadic occurrences of copper, lead, zinc, gold, and silver are sometimes found in subordinate quantities. Along the Yangtze Valley and in Central China, extending eastward as far as Shantung, are found here and there intrusions of dioritic rocks, in which occur the famous contact deposits of iron ore, besides which minor quantities of copper. lead, and zinc are also found. In South China the igneous intrunsions are of granitoid type in which, or in the vicinity of which, occur in certain regions immense deposits of antimony, tungsten, tin, and mercury. Broadly speaking. most of the famous coal mines are now situated in regions north of the Yangtze River, in which occur also the sedimentary deposits of iron in contradistinction to the contact deposits of iron along the Yangtze Valley.

Jan 1, 1943

By C. J. Slaughter, S. P. Harteis, L. L. Chasko, D. W. Alexander

The Department of Health and Human Services (HHS), National Institute for Occupational Safety and Health (NIOSH), Office of Mine Safety and Health Research (OMSHR), with the assistance of cooperating underground mining operations and state agencies, has conducted research exploring devices and technologies that could be used to assist miners navigating through smoke and dust resulting from a fire or explosion. Recent events in mines confirm that smoke and dust can enter and contaminate mine escapeways, creating an atmosphere with severely reduced visibility. This reduced visibility results in substantially increased escape times, possible disorientation or confusion, and increased stress levels, and may prevent evacuation altogether. Tools or devices that assist miners in navigating through smoke-filled areas void of lifelines could make the difference in successful escape from the mine. This paper presents the results of OMSHR research to identify and evaluate tools and devices that could provide meaningful information to evacuating miners in areas with limited visibility and without the benefit of a lifeline.

Jan 1, 2011

By A Salama, J Greberg, B Skawina

In today’s underground mass mining, the orepass is an important part of the infrastructure as it connects two or more mine levels and is used for conveying or storing large amounts of material. One of the main risks related to an orepass is when operational or structural failure occurs, leading to long-term loss of functionality. Developing or rehabilitating an orepass when major failure has occurred is a time-consuming and expensive operation, and the risk of a long-term orepass loss motivates the development of alternative transportation strategies to ensure the continuation of smooth operations in large underground systems. The study presented in this paper has been done at the Loussavaara Kiirunavaara AB Malmberget mine in Sweden, where iron ore deposits are being extracted using sublevel caving. The study analyses the transportation system in one of the mine’s orebodies using discrete event simulation, with a focus on maintaining ore transportation in the event of the loss of an orepass.CITATION:Skawina, B, Greberg, J, Jonsson, K and Salama, A, 2016. Orepass loss mitigation approach in Malmberget mine, in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016), pp 617–622 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016

By M. Beus, S. Inverson, B. Stewart

Abstract Recent ore pass failures have underlined the need for improved designs, standards, structural mon¬itoring methods and better hang-up prevention and removal tech¬niques. Researchers at the Spokane Research Laboratory of the Na¬tional Institute for Occupational Safety and Health (NIOSH) are investigating methods to improve safety during the transport of ore in ore passes. Design criteria and hang-up prevention and remedia¬tion strategies involve studies of the effects of static and dynamic ore and waste-rock loads on chutes, walls, gates and support structures. Particle flow analysis methods were used to simulate the response of various ore pass designs to a wide range of ore loading condi¬tions. A full-scale mockup of ac¬tual ore pass and chute assemblies was duplicated and tested for load response. Data from a particle flow code and the mock-ups were com¬pared Loads on an active ore pass chute were measured.

By P. A. Mingione

"AEROPHINE@ 3418A is a unique sulfide mineral promoter produced by Cyanamid, based on phosphine (PH3) chemistry. It has proven effective as a collector for the sulfide minerals of copper and particularly lead (galena), as well as for secondary gold and silver values. AEROPHINE 3418A has widest application as a Cu and/or Pb collector for complex ores of Cu-Zn and Pb-Zn, which frequently have significant quantities of associated precious metal values. Advantages shown in the use of AEROPHINE 3418A are improved selectivities against Zn- and Fe-sulfides, increased precious metals recoveries, reduced total collector consumptions for Cu and/or Pb flotation, and increased flotation kinetics leading to higher recoveries of these values. Operating plant, pilot plant and laboratory test data from treating different ores are presented, demonstrating the advantages in use and preferred application of AEROPHINE 3418A.INTRODUCTIONCyanamid operates the only phosphine and phosphine derivatives plant in North America, located in Niagara Falls, Ontario. Specialty chemicals manufactured at this facility are used in many diverse applications, including solvent extraction reagents and textile flame retardants. A unique phosphine-based sulfide mineral promoter, AEROPHINE 3418A, is also produced. The origins of AEROPHINE 3418A promoter date back to the 1960's, when it was established that sulfide mineral collectors based on phosphine chemistry demonstrated efficacy. This new collector chemistry was found to provide flotation performance differing significantly from those of more traditional thiol collector chemistries such as xanthates, dithiophosphates, mercaptobenzothiazoles, thionocarbamates and those with xanthogen groups. Some of the advantages ultimately demonstrated by AEROPHINE 3418A promoter compared to these traditional collectors include:"

Jan 1, 1990

By Jr. Koch

As a means of investigating the distribution and variability of gold in ore from the Homestake mine, Lead, S. Dak., the Bureau of Mines performed a designed sampling experiment, and assay results were statistically interpreted. Fifty-six feet of diamond-drill core from five boreholes was sawed into l-inch-long cylinders, which were sampled randomly and were assayed. Analyses of variance of the assay results were used to compare and assess the different types of variation: within drill holes, among paired drill holes, among unpaired drill holes, and among furnace runs. The extreme variability in gold mineralization found is the natural variability on the smallest scale that can be detected by fire assay; most of the variability is associated with among-feet rather than within-feet sample intervals. Because of the extreme variability, one-half of the gold is in 3 percent of the samples.

Jan 1, 1967

By Alvin Kaufman

To aid industry and Government in planning water developments the Bureau of Mines in 1963 canvassed mineral producers to determine water use in 1962. Water use by the mineral industry comprises only 2 percent of the water withdrawn by industry as a whole. The major water-using mineral industries are natural gas processing, phosphate rock, sand and gravel, and iron ore. Analysis indicated the following conclusions: 1. Total water use and new water intake is dependent on the quantity of material processed and the process water requirements of the particular industry or commodity. 2. Recirculation is dependent on the processing requirements of a particular commodity, the manner in which the water is used, cooling and condensing requirements in certain large industries, the quality of new water intake, and the need to treat new and discharged water. 3. Consumed water is dependent on the quantity of water recirculated, the temperature and humidity in the area, and the proportion of water used for cooling and condensing. 4. A threefold increase in water use by the mineral industry by 1985 is forecast.

Jan 1, 1966

By Dennis S. Kostick

Salt is a universal mineral commodity used by virtually every person in the world. Although a very common mineral today, at one time, it was considered as precious as gold in certain cultures. This study traces the material flow of salt from its origin through the postconsumer phase of usage. The final disposition of salt in the estimated 14,000 different uses, grouped into several macrocategories, is traced from the dispersive loss of salt into the environment to the ultimate disposal of salt-base products into the waste stream after consumption. The base year for this study is 1990, in which an estimated 196 million short tons of municipal solid waste was discarded by the U.S. population. Approximately three-fourths of domestic salt consumed is released to the environment and unrecovered while about one-fourth is discharged to landfills and incinerators as products derived from salt. Cumulative historical domestic production, trade, and consumption data have been compiled to illustrate the long-term trends within the U.S. salt industry and the cumulative contribution that highway deicing salt has had on the environment.

Jan 1, 1993

By S. Banisi, A. R. Hasankhoei, A. R. Ghasemi, E. Razi, G. A. Parsapour

At the pelletizing plant of the Gol-E-Gohar mining and industrial company two parallel dry closed grinding circuits, each with the average throughput of 300 t/h, are used. Each grinding circuit consists of a burner, a dry ball mill (6.2 m×13 m) and an air separator. The ball mill consists of a 2 m-long drying and an 11 m-long grinding chambers. The iron ore concentrate is fed to the drying chamber by a feed chute. The first 1.35 m of the drying chamber consists of 56 flights in two rows to decrease the feed moisture from 5% to below 0.2% and the rest of dryer chamber consists of deflectors to pass the material to the grinding chamber. It was found that when the feed moisture content increased from 1.3% to 3.5%, the throughput decreased by 12% (35 t/h) indicating a low performance of the dryer. Monitoring the wear rate of flights for a period of 12 months showed that the first 0.8 m length of the flights length did not experience any wear. This means that about 59% of flights do not contribute in material distribution and drying. A DEM simulation of feed chute and the drying chamber demonstrated that due to the inappropriate design of feed chute most of materials do not get in touch with the first 0.8 m length of the drying chamber. To overcome this problem, various feed chute designs with different geometries were simulated by the KMPCDEM© software. With the aim of arriving at a proper material trajectory, where the total length of the flights are used, a new feed chute was selected. The simulation results indicated that if the height of the flights is increased from 1.60 to 2.26 m and the slope is increased from 45 to 48 degrees the material arrive at the first 0.48 m of drying chamber. In this manner, the unused part of the drying chamber decreases from 59% to 36% of the length. After installation of the new feed chute, during a period of three months the throughput increased by 36 t/h.

Jan 1, 2018

6889. Aslakson, C. I., and Swick, C. H. Gravity Observations in Peru and Colombia. Coast and Geodetic Survey,-Special Pub. 233, U. S. Government Printing Office, Washington, D. C., 1943, 18 pp. (Price, 10 cents.) In accordance with the policy of cooperation among American republics, the-United States Coast and Geodetic Survey in 1941 made gravity surveys in Peru and-Colombia. The information was desirable for determining the figure of the earth for geophysical purposes and for studying the relationship between intensities of gravity and deflections of the vertical. The survey instrument was the Brown pendulum apparatus. 11 gravity stations were established in Peru and 13 in Colombia. The results obtained at these stations are given in a table covering observed gravity, theoretical gravity, and anamalies. - V. S.

Jan 1, 1943

By Karl J. C. Harries

"2.1. INTRODUCTIONNo agreement can be perfect in the sense that it contemplates and provides for all eventualities. Mineral acquisition agreements are usually negotiated and drafted at a time when an orebody is no more than a gleam in a geologist’s eye, so it is hardly possible to provide for development and operation in other than the most general terms. However, an agreement that stops short of contemplating the possibility of an orebody and production is ill-advised. Accordingly, it is important to provide procedures to make decisions that will let the project proceed, even in the face of a fallingout between parties. Whether the parties are shareholders in a corporation or venturers in a contractual common undertaking like a joint venture, differences of opinion and disputes will occur. Unfortunately, more and more are ending up before the courts. Besides greed and the growing tendency in society to fight rather than talk, there are other factors that contribute to the increase of litigation. In some jurisdictions, agreements have tended to become complicated, often defying interpretation, even by a lawyer, and explorationists want their budgets to go into the ground as constructive work rather than into a lawyer’s pocket. All this has led to a growing tendency for corporations to take the attitude that the chances of finding a mine are, at best, marginal and there are lots of earlier agreements in the files to draw from, so why not prepare their own agreements? As discussed in the preceding chapter, this can be folly. All these factors can quickly have parties facing each other in court while a project sits idle. Added to this is the problem that, in some jurisdictions, lawyers may take cases on a contingency-fee basis, sometimes promoting the pursuit of a nebulous claim.When an orebody is discovered, someone will always want some, or more, for himself. There is a breed of “prospectors” who prospect for legal actions, on the somewhat sound grounds that a major corporation will buy off nuisance litigation, rather than incurring the cost and effort of attacking even a poorly founded claim in the courts. They may even find a winner. Besides, it is far more comfortable and relaxing to prospect for problems and legal niceties than to prospect for an orebody.1 In short, it is appropriate to consider briefly some of the factors relating to lawsuits and judgments. Although many of the comments are made in the context of the common law and the Canadian legal system, most of the concepts and suggestions are applicable to any legal system."

Jan 1, 2003

By W. A. Lang

Introduction That the coal industry has entered a new phase in its development is now evident. Coal, besides being the chief source of heat and power, has become a potential raw material for many industries. Rapid progress has been made in the methods used in the mining and preparation of coal, and in the equipment for the burning of coal. Data of a fundamental nature relating to the composition of coal and to its transformations? during combustion and processing have also been revealed. Research, the key which has opened this new era, has already accomplished much, but it has only begun to show what it may and should be able to do. New developments of coal burning equipment, super-power plants, carbonizing and briquetting plants, hydrogenation and synthetic chemical processes, will undoubtedly have a marked influence in the post-war years on the economic welfare of many coal producing countries. Until comparatively recently, however, there has been in many branches of the coal industry a tendency to regard research as something abstruse and something which had little or no value to those managing such branches. But the fact that coal has suffered as a source of heat and energy through inroads of oil, natural gas, and water power, has made it plain to the industry that, if it is to maintain its present markets in this competitive world, much less increase them, the whole industry must be willing to follow the example of other industries and plan for the future.

Jan 1, 1946

By Jr. Hazen

This report documents 653 sets of sample data involving 78,366 assays obtained from past exploration for various minerals and metals. Most of these data have been taken from published reports describing exploration projects, conducted jointly by the Bureau of Mines and the Geological Survey, for the Strategic Minerals Program from 1940 through 1949. Means and standard deviations have been computed for the exploration assay data and have been plotted on graphs for 22 minerals and metals. A mathematical model, based on the binomial distribution, has been developed to explain the configuration of the plots of the exploration means and standard deviations. The two statistics, mean and standard deviation, which describe assay data, have been used for simulating probability models. These probability models then have been combined with the binomial model of the exploration assays and related to the sequential decision process associated with exploration drilling for mineral deposits. These probability regions can be used to form the basis for sequentially predicting the probable range of the average grade of mineral or metal that may be expected as an exploration drilling program is continued after the initial discovery of mineralization has been made.

Jan 1, 1966

By A Litwinowicz, M Laxman, A Fourie, A L. Li

This paper presents a design approach and analytical methods that were used for assessing the potential of static liquefaction and developing the mitigation measures for a tailings dams. The rigour of the design and analysis approach represented leading practise in the industry to address static liquefaction, which contributed to a robust design with high confidence and certainty. The salient features of our approach to static liquefaction included geotechnical investigation and tailings characterisation, static liquefaction screening assessment, static liquefaction triggering analysis, limit equilibrium analyses and numerical modelling of static liquefaction using the NorSand model, which was amongst the first tailings dam projects involving numerical modelling of static liquefaction using these methods.

Jul 1, 2021

By R. Marleau, R. Assad, J. Dugas

"A study of the geological features of known occurrences of mineralization in Gaspe is the basis for a classification. Nickel, chromite, asbestos and some copper are pre-or syn-Taconic, whereas the most important deposits are tied to granitic post-Taconic stocks. Most occurrences are clearly related to igneous rocks: nickel, chromium and asbestos to Ordovician serpentinite; copper to volcanic rocks of different ages; and copper, zinc and lead to acidic intrusions with apparent zoning. Some lead-zinc deposits lying between the Grande Greve and York Lake formations are stratigraphically controlled. Some occurrences are tied to faults; e.g., the nickel-copper mineralization along the North Grand Pabos fault. Northerly-trending transverse structures appear to coincide with the Gaspe Copper, Mount McGerrigle (Tabletop) granite and Lemieux dome areas of mineralization. JEAN DUGAS, after graduating"

Jan 1, 1969

By Bruno Lafrance

Abstract - Quartz veins at the Mufferaw gold prospect and Komis gold deposit, northern Saskatchewan, are examples of oblique-extension veins that crystallized in shear and tensile fractures, which propagated and then opened oblique to their walls during a single continuous deformation event. The Mufferaw gold prospect consists of an interlinked mesh of conjugate shear fractures, tensile fractures, and veins. Oblique-extension veins crystallized in conjugate shear fractures, which opened during dilation of intersecting tensile fractures under the same far-field stress system. At the Komis gold mine, tensile and dextral shear fractures cut across granodiorite dikes. The tensile fractures formed perpendicular to the dike margins during stress transfer from the less-competent country rocks to the more-competent dikes. During extension of the dikes oblique to the bulk extension direction in the country rocks, the tensile fractures were reactivated as sinistral shear fractures. The reactivated tensile fractures and dextral shear fractures opened oblique to their walls, parallel to the bulk extension direction, and were sealed by the deposition of oblique-extension veins during the same deformation event.

Jan 1, 2004

By James R. Finlay

SOMETIMES the American Institute of Mining and Metallurgical Engineers appears to be a strictly technical society, and if so my paper should deal with the technical operations of finding and producing gold. But I have not been engaged in practical gold mining since 1910. What I have been doing mainly for the last 25 years is to try to figure out what the income of a mine-gold, or any other-would be worth to an investor. So I have been in contact with gold mining, in one way or another, for some 42 years. I say that with a purpose. In that time the industry has been through one of its cycles. The value of gold mines is very dif¬ferent at different points in one of these cycles. For this reason the cycle of gold mining is a highly practical study. The cycle of gold is a more or less rhythmical change in its value or purchasing power measured in the grand average of other commodities, which is the same thing as its price. Taking the price of gold in 1897 as a stand¬ard, a dollar at that time declined to 55c. in 1913, to 26.8c. in 1920, and since then it has risen to 47.4c. in 1930 and to about 64c. in 1932. It is worth about 21/ times as much now as it was in 1920, but less than two¬thirds as much as in 1897. When this change is applied to the value of a gold mine still greater differences are evident. The cost of producing gold is of course measured in labor and other commodities, and as that cost goes down the margin of profit measured in the gold itself increases. Thus a mine which might make only 10 per cent profit in 1920 on its gross output may easily make 25 per cent now. The stockholder gets 2 ½ times more gold that is worth 2 1/2 times as much in purchasing power, therefore the real value of his holding has risen by the one factor multiplied by the other, giving him 61/4 times as much goods or services as he had in 1920.

Jan 1, 1933

A glance at the accompanying table reveals that for the first time in many years the industrial minerals field did not post significant gains in production. Gypsum, cement, sand and gravel, and crushed stone production-which are very sensitive to construction industry performance-barely managed to stay even, or in fact, declined slightly. Even barite production, in spite of increased oil and gas drilling, was off 5% in 1979 from 1978. Domestic fluorspar production continued to decline while imports, primarily from Mexico, South Africa, and Spain, rose 11%. Worldwide production of iodine (which is used primarily as a catalyst, animal feed additive, and in ink and colorants, stabilizers, pharmaceuticals, photographic film, and disinfectants) grew about 9% on a worldwide basis-from 10.75 Tg to 11.16 Tg. This does not include US production. The two US producers increased demand as apparent domestic production increased about 5%. Increasing energy costs and the transportation situation have had a prohibitive effect on the industrial minerals field. The critical shortage of railroad cars, according to consultant Neil Johnson, is due to several factors: • High capital investment rind interest rates needed to build new equipment, • Accidents, obsolescence, and failure to repair equipment reduced car availability, •Reduction in some train schedules due to fuel economy, and •Increased turnaround time as a result of new safety regulations. Railroad rates have increased an average of 7% per year for the past 10 years. Last year's increases were about 11.1% due to fuel costs and surcharges. Truck shipments have increased their penetration in certain areas of the southeast because of the shortage of box cars and the producers' demand for quick shipment. Some producers report a 15-20% increase in truck use. In the feldspar-mica area, which formerly made most shipments by rail, trucks are now used for about half the shipments. Marketing prices, as expected, increased due to higher costs for energy, power, labor, and supplies used in production. Estimated average price increases were about 10% which, in many cases, did not cover increased production costs. These factors-rising energy costs and the critical transportation situation-resulted in an unsatisfactory year for industrial minerals. Stanley J. Lefond Cnntrihuting Editor

Jan 5, 1980

By C. A. Stewart

I. INTRODUCTION AND GENERAL STATEMENT OF RESULTS. The field-work upon which this paper is based was done in the summer of 1910, and was made possible by the courtesy of the Imperial Copper Co., which gave me access to its property. For their kindness in this respect I wish to express my thanks to W. F. Staunton and Meade Goodloe. Moreover,. B. F. Smith and G. B. Gentry, mining engineers in the employ of the company, gave invaluable assistance by placing maps,. etc., at my disposal, and by discussing with me the problems of the district; and it is a great pleasure to acknowledge this indebtedness to them. In order that the significance of some of the details that follow may be better appreciated at first reading, a general outline of the conclusions reached is given here. In the Silverbell mining-district a series of Palaeozoic limestone blocks is completely surrounded by post-Palaeozoic igneous rocks, intruded in the following order: alaskite, alaskite-porphyry, biotite-granite, andesite, and quartz-porphyry. The biotite-granite is believed to represent a differentiation of the. magma from which the alaskite-porphyry came ; and this conclusion-has an important hearing on the origin of the ores. The intrusion of both alaskite-porphyry and biotite-granite was followed by the emission of magmatic waters, which sericitized and silicified the alaskite-porphyry and granite, and produced in the limestone, by the addition to it of silica, iron, and alumina, great masses of garnet, quartz, and wollastonite. Following close upon these solutions came metal-bearing magmatic waters, which impregnated porphyry, granite, and alas kite with cupriferous pyrite, and deposited in the garnet zones chalcopyrite and copper-bearing pyrite that make important bodies of contact-metamorphic ores. Secondary enrichment has taken place in the disseminated ores in the igneous rocks,. raising their copper-content to 2 per cent. in some cases,. and extensive drilling has been undertaken to block out these deposits. East of the contact-metamorphic deposits there is a fissure-vein of lead-silver ore in the quartz-porphyry. This rock is distinctly younger than the alaskite-porphyry and the granite; and the lead-silver ores belong, therefore, to a period of mineralization distinctly later than the copper-deposition.

May 1, 1912