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The copper and zinc contents of herbarium specimens of 11 of the 12 Australian species of Polycarpaea were determined in order to establish background and anomalous values of potential use in biogeochemical prospecting.Cumulative frequency curves were used to establish appropriate threshold concentrations for six species including the "copper plant"' P spirostylis. Collection localities of Polycarpaea specimens with anomalous copper or copper-and-zinc values are under investigation.

Jan 1, 1978

By Corneille S. Ek

Flotation of several copper and lead-zinc ores has been carried out with mercaptobenzothiazole (MBT) as promoter. The results of laboratgory batch flotation tests have been compared with those obtained when using more common collectors like xanthates or dithiophosphates. It generally appears that MBT is an effective collector of all the sulfides, including pyrite, but that high selectivity is rather difficult to attain, except for gangue drop-out. Some kinetic tests have been performed to check the froth production rate by MBT as compared to other collectors.

Jan 1, 1995

By R. J. Sweigard

Productive and beneficial use of reclaimed surface-mined land is a concern of industry, government, and the general public. An investigation was conducted of current mined-land planning practices to aid in the development of a procedure for evaluating postmining land use potentials. This investigation considered both the industry and public planning approach to mined-land planning and was based primarily upon three case studies conducted in various regions of the United States. The site planning process that was developed during the investigation is iterative in nature and has been designed specifically for the mining industry. It centers around preliminary studies and data collection, development of land use alternatives, and the evaluation of alternatives. Use of this process facilitates the evaluation of economic, environ- mental, and social impacts of postmining land use alternatives. In this paper, the process is presented along with a description of its development, application, and significance.

Jan 1, 1984

By S. P. Goplen, M. Henriksen, T. F. Barron

In the past decade, numerous large scale drilling projects have made use of reverse circulation air lift methods. Reverse air lift pumping can be established by injecting gas into a column of liquid; the subsequently decreased density of the gas-liquid mixture allows atmospheric pressure outside the lift conduit to establish flow. The rate of flow can be controlled by varying the gas to liquid ratio. A typical reverse circulation air lift system is depicted in [Fig. 1]. Allen 1 has described a number of reverse air lift drilling projects. Although cited examples are generally related to large diameter holes, the method has seen use in other applications such as sand dredging, chemical pumping, water well pumping. and continuous coring. One particular benefit obtained with enclosed reverse circulation drilling is elimination of lost circulation. The required air/water ratio for pumping at a given submergence and lift has been established experimentally by Gibbs.2 His data, however, do not reflect sensitivity of flow rate to air/water ratio. Further, in Gibbs' work, air apparently is injec-

Jan 1, 1980

By Tara Schenk-McFarland, Mark Bliss

Echo Dam, located near Coalville, Utah, is a facility that provides storage for irrigation and municipal use. Original construction of the dam was completed in 1931. Because of seismic concerns, the spillway crest structure and upper chute section, founded on old landslide and colluvial material, were recently replaced. Prior to replacement of these structures, jet grouting of a block of the loose and potentially liquefiable soils, directly beneath the spillway crest structure was selected as the preferred alternative to address the potential for settlement and cracking of the spillway crest structure. The replacement or alteration of the in-place soil reduces the likelihood of seismic-induced excess pore pressure development and subsequent settlements. Core drilling and sample recovery of the production jet grouted columns was completed to verify compliance with the specifications. It was recognized that due to the larger rock sizes within the deposits that full homogeneity of the jet grouted zone was unlikely to be achievable. However, the purpose of this jet grouted section was to strengthen enough of the soil so that widespread liquefaction does not occur. During the jet grouting production many instances of ground fracturing occurred. Fracturing was evident based on grout/air bubbles exiting the surface near some of the grout holes during jet grouting, air bubbles appearing in the spoil pits, and lifting of the ground surface in the vicinity of the monitor during the jet grouting process while the system was pressurized. In one instance, a section of the upstream spillway slab, which was left in place, was cracked due to pressurized grout escaping beneath the slab. The overall results of the jet grouting were satisfactory despite difficulties encountered. The cause of the fracturing is hypothesized and a recommendation is included to reduce the likelihood of this occurring on future jobs.

Jan 1, 2017

By T. M. Olson, B. G. Lewis

The adsorption of selenite on bentonite, kaolinite, and an iron--coated illite was studied to determine the importance of several soil variables on selenite removal from uranium mill tailings pond seepage. Adsorption capacities of the clays of selenite varied by orders of magnitude and decreased in the following order: illite > kaolinite > bentonite. Maximum adsorption of selenite on the clays was observed between pH 2.5 and the clay's zero-point-of-charge. Substantially less selenite was adsorbed on these clays in actual mill tailings solutions than in model systems. Virtually all selenite was removed from the tailings at pH 7. The principal removal mechanism at this pH is suggested to be the adsorption of selenite on freshly precipitated metal hydroxides. It is concluded that selenite can be removed from tailings seepage in soil or in clay liners in the presence of kaolinitic clays and iron oxides. Selenite would also tend to be removed from tailings seepage in calcareous strata.

Jan 1, 1984

By Ruilin Yan, Kameron Ray

This paper reports a simple approach to model the waveform change due to travel distances based on the field measurement. A linear interpolation is used to estimate the waveform at a distance from two vibration waveforms recorded at two different distances. The resulted waveforms are compared with actual recorded waveforms at the point in both time and frequency domains. It shows that the proposed method to estimate the waveform change yield reliable results. The advantages of the proposed method are that it does not require assumptions that a transfer function does and that it is based on purely the measured waveforms that are encoded with in-situ rock properties. The method could be more reliable for far field seismic waveforms and could be an approximation for near field waveform estimation.

Jan 1, 2014

By Antonio Jorge de Sousa

In order to compare several mining variants, on the point of view of the variability of the ore quality parameters, a conditional simulation technique is applied to a complex pyrite deposit (FEITAIS orebody, Portugal). Exploitation methods such as cut and fill and sublevel stoping are studied by the a.m. methodology. For each mining variant, it is assessed the influence of several mining operators on the variability of grades.

Jan 1, 1982

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

Reduce worker exposure to respirable dust without interfering with bag-filling operations. Approach A dust control hood was developed which contains and captures dust close to its source and prevents it from entering the bag-filling operator's work place. How It Works A sheet metal hood is placed around the nozzle of the bag filling machine. The hood is connected through ducts to the plant exhaust ventilation system. Air pulled into the front of the hood and around the sides of the bag picks up dust generated inside the hood, and carries it to the dust collector. The size of the hood can be adapted to fit most fluidized valve-type bag-filling machines. The height of the hood depends on the bulk density of the product and weight of the bags being filled. The 14-inch-width of the hood allows it to be used on multi-nozzle baging machines spaced 16 inches on center. Only 2/3 of the bag is actually within the hood, and this allows easy operator access for placing the bags on the nozzle.

Jan 1, 1978

By Subagyo, Geoffrey Brooks, Ken Coley

The generation of droplets and their subsequent reaction in the emulsion is critical to the overall kinetics of oxygen steelmaking. High temperature experiments have been performed at McMaster University to study this behavior. The results from this work and other previous studies has formed the basis of a number of physical and chemical models that attempt to describe the critical aspects of droplet behavior in Oxygen Steelmaking. These models include semi-empirical models for predicting droplet generation rate, droplet size distribution and droplet residence time as a function of blowing parameters.

Jan 1, 2004

By D. L. Petersen, C. R. Nelson, B. K. Nelson, B. D. Wagener

The Lafayette Bluff tunnel, currently under construction for the Minnesota Department of Transportation (MnDOT), will be among the widest highway tunnels in the United States. The 199-meter tunnel is being constructed in a closely jointed, variably weathered diabase rock mass. Cover above the tunnel crown ranges from 4 meters to 27 meters, and is less than the tunnel excavated width of 18.3 meters for about 60 percent of its length. These factors dictated special support and lining design, limitations on excavation sizes and required sequences for support installation. Tunnel excavation is by controlled blasting, with multiple top headings and bench. Rock support and lining consists of external portal beams, rockbolts and reinforced shotcrete. A final concrete lining provides structural support for the rock mass and the membrane waterproofing system.

Jan 1, 1991

By Alan J. Fejes

As part of its mine subsidence research program, the Bureau of Mines and the American Electric Power Co. cooperated on a study, conducted at the Price River Coal Co. No. 3 Mine, directed toward developing the capability to estimate the surface subsidence resulting from longwall mining in a geologic, topographic, and mining environment common to coalfields in the Western United States. Subsidence was monitored at the No. 3 Mine over two adjacent longwall panels. The subsidence study area was reduced when the two planned panels were reduced in length because of equipment failure and a mine fire. Subsidence was measured for 21 months. Subsidence continued for 6 months after mining had been completed. A maximum of 2.2 ft of subsidence occurred over the two longwall panels mined at an overburden depth ranging from 300 to 1,500 ft.

Jan 1, 1986

IDO not want to omit anything in which fire or its operation has a part, if I know or can tell it, and have already told you so many other useful, powerful, and ingenious effects (finally of powder and other' fire deadly and very injurious to all living things, indeed, composed for the destruction of those who possess it as well as those who do not) but I do not want the end of my writing to be in tragedy. Therefore I wished to tell you how, from these fires composed of forceful and horrible mate¬rials bringing harm and terror to men, a happy and pleasing effect is also produced and, instead of fleeing from it, the people willingly go to see it. Among others I remember that it was once customary to use these in Florence and in Siena, more than elsewhere. The chief feast day celebrated. by one of these cities is the day of the birth of Saint John, and the other is the Assumption of Our Lady, on the fifteenth of the month of August. In the morning they visit the shrines with great devotion and solemnity, displaying their pomp as much as possible, and later they hunt lions, wild bulls, untamed horses, and many other animals. In the same public squares there was also erected as a decoration an edifice fixed in the ground in the middle of this space, or hanging from a heavy rope crossing between the loftiest points of equal height that could be found in that place. This they have done and still do, and perhaps in time to come will continue to do when opportune. This structure was usually of wood; indeed it is necessary that the latticework of its construction be made only of this. It was covered and en¬larged by tying and fastening hay on top to bring it almost to completion and then papier-mâché was applied. [165v] The figures were first appropriately painted and made of a combination of vessels one above the other, developing various decorative figures in relief which should represent some fable or history and should not appear haphazardly made or without understanding. Now the master proceeded to arrange these figures in a composition according to his skill or art of design, and likewise planned

Jan 1, 1942

By Arthur L. Murray

"Oil-shale camps are peculiarly favored, in that before they are establishes it can be ascertained with a degree of certainty, that the life of the project is not limited. Unlike camps at metal mines, where the metal content of a given area is frequently an unknown quantity until after years of development, oil-shale camps should, from the outset, be planned and. built as permanent types of camps. Where this procedure is followed camps will be established which better serve the needs of the industry and the cost of their general care and upkeep will be less.Selection of camp or townsite.The site of the camp or town' whether on company property or not, should be selected with care. It should be separate if possible from the location of the plants of the company so as to be free from noise and fumes and so as to provide a change of environment for employees in going from their work to their homes.The principal features governing the site to be selected are as follows:Drainage. The general contour of the surrounding country should be such that drainage is away from the site. The camp or town should, if practical, be situated on higher ground than that in its immediate vicinity.Soil. The nature of the soil on which the camp or town is located may bear a decided relation to health. A porous, well underdrained top soil of at least four feet in depth insures dryness and facilities the placing of foundations and the laying of water mains and sewer pipes. Such a soil also is an advantage in growing trees, shrubs and grass plots, which are a decided adjunct to making the community attractive.Enviroment. The contiguous territory should afford no unwholesome sur¬roundings such as swamps Or accumulations of stagnant water.General Considerations. The water supply to be provided and the method of disposal of wastes influence to a certain extent the location of the camp or town-site. The means of supplying water, whether by gravity or by pupping, and the disposal of sewage, whether by outfall, system, sewage disposal system through septic tanks, broad irrigation or filter beds, or cesspools will govern the location of the site topographically in relation to source of water and point of disposal of sewage.* This article was prepared as part of the paper ""Use and Supply of Water for the Oil-Shale Industry"" by J. J. Jakowsky, to be published by the Department of Metallurgical Research, University of Utah, in cooperation with the United States Bureau of Mines."

Jul 1, 1921

By C. Edwards

ABSTRACT The versatility and specificity of rare earth elements (REEs) have led to their use in an everincreasing variety of applications in new technologies; consequently, demand for REEs has increased significantly. However, separating REEs safely and effectively is a complex and expensive process. This paper presents a review of REE mineral processing technologies, providing an update on current capabilities in REE mineral processing and REE extraction from the major commercially valuable REEbearing minerals such as bastnaesite, monazite, and xenotime, as well as the ion-absorption type of REE deposits.

Jan 1, 2013

By Wouter Bleeker, Isabelle Cadieux

"Abstracts of theses related to mineral deposit studies and exploration, completed at geology or earth science departments of Canadian universities, have been compiled for the period 1991 to mid-I993. Part I, presented in the June, 1994 issue of the CIM Bulletin, gave a listing of thesis titles. Part II. which consists of edited abstracts of theses considered to be of direct application to mineral deposit studies and exploration. is presented under various themes as follows:A. Kimberlites, Other Alkaline Intrusions and Related Studies;B. Volcanogenic Massive Sulphide Deposits and Related Studies;C. Mineral Economics;D. Mesothermal Gold Deposits. Other Gold Deposits and Related Studies:E. Magmatic Nickel-Copper, Platinum Group Element and Chromite Deposits and Miscellaneous Platinum Group-related Studies;F. Granite and Pegmatite-related Deposits and Porphyry Deposits;G. Diverse Hydrothermal Deposit,>, Sediment-hosted CopperDeposits and Mississippi Valley Type Lead-Zinc Deposits; andH. Uranium-related studies, Evaporites and Exploration Geophysics.Abstracts related to themes A to F were presented in previous issues of the CIM Bulletin, abstracts related to themes G and H are presented in this issue.G. Diverse Hydrotbennal Deposits, Sedimenthosted Copper Deposits and Mississippi Valley Type Lead-Zinc Deposits"

Jan 1, 1995

By lndu S. Das

An analytical simulation of the material characteristics of Inconel 718 is developed and bounds for mechanical and microstructural stability are obtained for isothermal and temperature-dependent cases. Experimental flow stress data using hot compression tests are reported for a wide range of temperature and strain at various strain rates. A parametric study of strain rate sensitivity, dissipation and entropy are presented. A complete set of processing maps delineating the stable and unstable regions are developed to help define the most efficient means of manufacturing an Inconel product.

Jan 1, 1992

By J. G. Russell

The valuation of known mineral re-serves entails the economic evaluation of the mining enterprise and the valuation of other assets employed, including mining and processing plant and intangible assets. A case study approach analyzes two reserve situations: ownership of reserves (phosphate rock), and leasing of reserve lands (kaolin). The appraisal of the physical property is outlined, along with the economic analysis of the operation. The discounted net cash flow approach is used to value the enterprise, leading to value of the reserves after correlation with other assets employed.

Jan 1, 1989

By P. A. C. De Ruiter

The Lower Cretaceous salt deposits of the Gabon Basin and Congo Basin were said down on ton of an Burly Cretaceous Lato Jurassic, continental graben fill that represent!) the rifting phase of the Afro-American continent. The salt 13 characterized by high percentages of potash and magnesium salts and the scarcity of sulphates and carbonates. The salt probably originated from a brine that was already enriched in high-soluble salts before entering the Gabon Congo basins. Their low-solubility equivalents are found in the Cuanza Basin of Angola. Commercial mining of the potash salt is only possible in those onshore areas where it is essentially undisturbed, shallow and of the right chemical composition. These conditions are net in Congo where the Holle mine produces from rich sylvinite deposits.

Jan 1, 1978