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By E. H. Burroughs

Persons interested in th_e study of petroleum and allied substances have long felt the need of a bibliographic index to the literature. This bibliography, which is intended to be the first elf a yearly series, has been compiled by the petroleum division of the Bureau of Mines with a view to satisfying this need. The references include only the more noteworthy writings that appeared during the year 191.5 in both ·the United States and foreign countries. Only patents plainly applicable to the industries in point have been included, although, of course, a close scrutiny of the great volume of patent literature might reveal many other patents of possible value. The references are arranged according to the subject classification on pages 3 to 11. This classification, which is to be followed in the succeeding bibliographies of this series, is offered as a guide for further study and classification of the pertinent literature.

Jan 1, 1918

By J. B. Clark

In multiphase ternary diffusion studies, plots of the variation bf the composition on the isotherm constitutes one of the most effective methods of presenting experimental results, especially if such plots are made in a manner which relates the composition path on the isotherm with the diffusion layer structure in the couple. Unfortunately, if different conventions for plotting are used serious misinterpretations occur readily, causing apparent disagreement between investigators who actually share the same viewpoint. A common convention for mapping these diffusion paths is needed at this time because with the increasing use of the electron-probe X-ray microanalyzer, a much greater number of ternary diffusion studies can be expected in the near future. In an effort to prevent unnecessary confusion in the future litera- ture, a convention for these plots is proposed, as outlined below. A hypothetical example of the use of these conventions is given in Fig. 1 where the path of composition through the diffusion structure of the 100 pct A/50 pct B, 50 pct C couple is plotted on the appropriate isotherm of the ABC system. The lower case letters relate the region in the diffusion layer structure to the appropriate composition on the ternary isotherm. 1) The diffusion path is plotted on the isothermal section corresponding to the diffusion temperature of the couple. 2) The terminal compositions of the plotted diffusion path are the initial compositions of the couple halves—provided infinite boundary conditions are maintained. If, in either couple half, infinite conditions are not maintained, then the path terminates at the composition of the exterior surface of the couple. If, at this surface, the composition varies with time or if the plotted path is time dependent, then the diffusion time should be noted beside the plotted path. 3) A solid line crossing a single phase field (e.g., line a-b in Fig. 1) denotes an existing layer of that phase in the diffused couple. 4) A dashed line crossing a two-phase field parallel to the tie lines (e.g., line g-h) represents an interface between the two phases with interfacial compositions designated by the ends of the tie-line. The line represents no spatial extent. 5) A solid line crossing a two-phase field so as to cut tie lines (e.g., line b-c or line j-k) represents a locally equilibrated columnar two-phase layer. The solid line should cut those tie lines which correspond to the lateral interfacial equilibria along the columnar

Jan 1, 1963

By I. A. Mwamba

Plain and alloyed titanium aluminides of composition Ti-47.5 at.% Al were prepared by melting commercial-purity titanium and aluminium with additions of 1 at.% precious metal. The as-cast alloys were subjected to potentiodynamic scans in 5, 15, and 25 wt% HCl aqueous solutions at room temperature and compared for their abilities to spontaneously passivate. Addition of precious metals resulted in a general improvement of corrosion resistance by increasing the open circuit potential to more noble values. Addition of 1 at.% gold or silver to titanium aluminide did not significantly increase the corrosion potential (Ecorr) above that of the plain titanium aluminide alloy, indicating that gold and silver are not sufficient cathodic modifiers to improve the corrosion resistance of titanium aluminide in all the solutions tested. However, platinum, palladium, and iridium additions shifted the corrosion potentials to the position of the passive region of plain TiAl for all solution concentrations. This indicated that TiAl alloyed with these platinum group metals would passivate spontaneously by cathodic modification. TiAl alloyed with palladium performed the best in 5 wt% HCl solution with the most positive corrosion potential. In 15 wt% HCl solution, alloys with platinum exhibited the most positive corrosion potentials, while alloying with iridium or palladium revealed more negative corrosion potentials. Thus, palladium alloying led to the best cathodic modification of titanium aluminide in low-concentration HCl solution, whereas platinum and iridium alloying additions resulted in the best cathodic modification of titanium aluminide in high-concentration HCl solutions.

Jan 1, 2013

As metal prices fluctuated over the years, so too have the fortunes of many of those mining in Canada?s Yukon province. With a rich mining history that dates back to the Klondike gold rush of 1896 to 1898 and continues to thrive today, Yukon has experienced several ?boom-and-bust? cycles. However, during the world?s most recent mining ?bust? Yukon has held strong and has re-mained one of the world?s hottest destinations for mineral exploration. In fact, the area even exceeded forecasts in 2009, more than doubling last year. And the near-future looks just as bright.

Jan 1, 2010

By J. P. BONARDI, J. C. Williams

Until the end of 1918 Boulder County ranked as one of the foremost tungsten-producing districts of the world, but in August, 1919, there was practically no production in the district. The operators there could not compete with tungsten ores from foreign sources, particularly China, Burma, and South America. As a. result there · has been a strong movement for placing a protective tariff on all imported tungsten ores and products; and it seems to be the general belief of tungsten producers that some form of protection is necessary to the maintenance of the industry in this country. The stimulus, due to the great demand for · tungsten alloys in the manufacture of munitions during the war, was felt in all the productive localities of the world. The ores of Boulder County were especially in demand on account of their comparative. freedom from • harmful impurities, and this demand greatly extended mining operations in the district and increased the efficiency of the gen~ral milling practice there.

Jan 1, 1921

By J Williamson, M Griessmann

"An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation. The Watershed tungsten deposit is located in the Hodgkinson Province of north Queensland, Australia. The deposit is hosted by Siluro-Devonian flysch-type meta-sediments of the Hodgkinson Formation, which were subjected to four major deformation events. Mineralisation has occurred syn- to post-D4 and is related to the intrusion of S-type granitoids of the Permian Whypalla Supersuite.Watershed is located within a regional NW–SE-striking melange zone composed of brecciated and intermixed arenites and shales. The major NW–SE-striking Tullah fault zone is situated in close proximity to the east of the deposit.The Watershed deposit occurs within a tightly folded upright anticline with NW-plunging fold axis. The anticline contains a major package of coarse-grained to conglomeratic arenite, which harbours the Watershed mineralisation. Several alteration styles occur within the arenites, of which Fe-poor calc-silicate alteration dominated by clinozoisite/epidote is the most significant. Less widespread but locally important alteration styles comprise garnet-dominated calc-silicate alteration, albitisation and sericitisation. The arenites are enveloped by unmineralised carbonaceous shales and shale breccias.Tungsten mineralisation occurs solely as molybdenum-poor scheelite and can be found as three styles: disseminated mineralisation in calc-silicate altered arenites, vein-style mineralisation with quartz-albite-scheelite veins and minor but high-grade mineralisation in albitised felsic dykes.Contact metamorphic rocks and geophysical data indicate the proximity of an underlying granitic body. It is believed that this granitic body was the main driver of the hydrothermal system generating the Watershed deposit. An early mineralisation stage caused the selective calc-silicate alteration of the arenites, while a second stage caused the vein-style high-grade mineralisation. The folded shales enveloping the arenites worked as an effective barrier that kept the mineralising fluids in a confined rock volume.The scheelite mineralisation at Watershed is open to depth, with a granite-hosted porphyry or greisen-style mineralisation anticipated below the current resource.CITATION:Griessmann, M and Williamson, J, 2015. The calc-silicate-hosted Watershed tungsten deposit, far north Queensland, Australia , in Proceedings PACRIM 2015 Congress, pp 545–550 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 18, 2015

By Jacob Chacko

The east span of the San Francisco-Oakland Bay Bridge (SFOBB), which is one of the most heavily traveled bridges in the world, will be replaced due to seismic safety concerns. The majority of the new bridge will be founded on large-diameter (1.8 to 2.5 meters), approximately 60- to 100-meter-long pile foundations The large-diameter steel pipe piles and soil conditions are similar to those used/encountered in many offshore structures. Thus, the design methods used are based on site-specific modifications to the procedures recommended by the American Petroleum Institute rather than the conventional procedures that have been formulated and used for the design of much smaller piles. Pile foundations will experience their maximum loads during the design earthquake. For the Safety Evaluation Earthquake, tension loads of up to approximately 80 to 90 meganewtons (MN) and compression loads of up to approximately 120 to 140 MN were calculated. Due to the economic importance of the SFOBB and the consequences of catastrophic failure in both economic and human terms, the design and analysis of the pile foundations supporting the bridge consider a number of aspects of pile-soil behavior that are normally ignored. Those aspects include: 1) the effects of consolidation and setup, 2) the behavior under dynamic loading, 3) the losses of resistance under cyclic loading, and 4) the load-settlement behavior of the piles under severe cyclic loading conditions. Since the treatment of complex aspects of pile foundation behavior is not codified in any guiding documents, several project-specific methods were developed for design and analysis of the foundation piles.

Jan 1, 2002

By A. Burger Pintér

To be meaningful the sharing of ideas about the National Environmental Management Act (NEMA) and social issues within the context of Mining and Metallurgy (M&M) requires an honest scrutiny of the M&M/social environment relationship, both past and present. It is not a secret that this relationship has been and is fraught with difficulties. Thus from all perspectives (M&M, society and environmental and social consultants) such a dissection, that highlights the realities, both good and bad, is uncomfortable. For this section of the colloquium to have any value, the honest but difficult approach needs to be taken.

Jan 1, 2000

THERE are certain facts that the mining industry in Australia is faced with at the present moment which may be accepted as axioms. The industry is at a low ebb, as evidenced by statistics. Metals form the basis of all modern industries, and are necessaryfor the welfare of Australia. Mining is a wasting asset. Every ton of ore extracted is one ton less which c.annot be made good, and it should be our duty to get as much profit froin that ore as possible, otherwise there is a permanent loss to the country.The metal market cannot be controlled by Australia; it is more or less an international matter. Australia has not been thoroughly prospected. There are no mines being developed that are likely to replace those which are being depleted.Our mining engineers are as capable as those in other parts of the world, and have made good where they have been given a chance. There is no one cause for the present depression; there are several, more or less, interwoven. Of course, the war has had an adverse effect, but that has only dislocated things temporarily; it upset our markets, influenced the price of metals, and affected the labour market and cost of stores. Labour troubles made their appearance before the wave of unrest swept over the world. The cause of labour discontent must be investigated, and if possible removed. As each industry has .its·own problems, miners must inquire into their special problems, as there is no sovereign remedy that will suit all cases.It is obvious that we cannot mine ore if we do not know where it is; therefore, the first thing is to discover workable deposits.

Jan 1, 1919

By George A. Morgan

The 53 countries that constituted Africa in 1991 accounted for a significant portion of total world output of a number of mineral commodities. However, total output for the continent declined for many major mineral commodities produced compared with that of 1990. Also, Africa's share of total world output of these commodities generally declined. (See tables 1 and 2.) The most conspicuous declines were for cobalt and copper owing to mining and metal processing difficulties experienced by the world's two largest cobalt producers, Zaire and Zambia. Phosphate rock output declined primarily owing to a sharp fall in production from Morocco, also a leading world producer. Morocco's state corporation for phosphate production experienced marketing problems, leading to the decline.

Jan 1, 1993

By L. T. Isaacs, W. H. Traves

A numerical model for analysing the drainage of fill in mine stopes has been described. The model can be used to analyse the process of fill drainage in existing and proposed mine stopes. The validity and potential value of the model have been established by experience with a simpler, 2-dimensional numerical model and by testing the new model against the earlier model. The new model is more useful than the 2-dimensional model because it allows for heterogeneity of fill material within the stope - a factor that has been demonstrated to affect drainage characteristics significantly. The 3-dimensional model is also capable of predicting pore pressures and drainage rates at specific locations in the stope without the need to resort to 2-dimensional generalisations. Such information, integrated with relevant field data as they become available, will provide valuable mine planning information for the scheduling of filling operations and design of fill mixes

May 1, 1991

By Patrick Pelletier, Pierre-Alexandre Bossé, Julie Fournier, Gianni Bartolacci, Jayson Tessier, Ahmed Bouajila, Carl Duchesne

"This paper summarizes research into the study of the control of flotation processes based on froth images. The use of numerical image analysis techniques for the extraction of significant patterns (froth structure and colour) from industrial flotation froths is discussed.First, the froth was analysed by the use of the Multivariate Image Analysis (MIA) method to extract the spectral variation contained in a RBG image. The Partial Least Squares (PLS) was applied to develop the empirical model for the prediction of froth grade. The results of this application are illustrated using one industrial case study.Second, the froth was also analysed by Gray Level Co-occurrence Matrix (GLCM) and Wavelet Transform Analysis (WTA) to extract features related more to morphological aspects. Since there is useful information hidden in froth texture, these methods are used as texture descriptor to classify different types of froths.Third, a control strategy based on a froth structure indicator was developed and implemented on an industrial zinc flotation circuit. The feedback controller uses a reagent flow-rate in order to maintain the froth structure at its set point. Process improvements obtained with the implemented control strategy are highlighted.Finally, the feasibility to implement a hybrid control strategy consisting in a froth structure supervision controller based on the froth concentrate grade estimated by MIA and recovery inferred by image analysis is discussed.INTRODUCTIONThe development of control strategies to achieve satisfactory control performance has always been a great challenge for engineers and the need for improved process diagnosis, control and optimization has become more and more evident for the mineral processing industry in the last decades. That is why new process variables need to be measured particularly in highly multivariable processes such as flotation. This industrial process is subject to a wide variety of disturbances mainly generated by frequent and sometimes abrupt changes in physical and/or chemical ore characteristics and also, due to some irregularities in manual process operating procedures. A flotation circuit scheme is always a complex network of more than two dozens slurry streams. Information about those streams (% solid, metal content analysis and flow rates) is important for process diagnosis performance evaluation and control. Also, because of the grade decrease and increasing complexity of the new processed ores, more instrumentation outputs and more powerful and significant pr"

Jan 1, 2005

By B. J. Schat, A. W. O. Bots, O. S. Langhorst

Amsterdam City Council is building a new metro line, the North–South Line. The line passes under Amsterdam Central Station (a listed building) about 18m below street level. The retaining wall that has to be built underneath the existing building is an innovative construction consisting of two rows of steel piles interspersed with a solid mass of overlapping jet grout columns: a composite ‘sandwich’ wall. This paper gives an overview of the approach taken to designing (computational models) and building the retaining wall. Special attention is paid to the observational method used for the construction of the jet grout columns.

Jan 1, 2007

By M. Bwalya, L. Mabokela, L. C. Woollacott

This paper presents a study on the ability of the King stratification modelto describe density stratification patterns that are achieved under idealizedconditions. Tests were conducted in a batch jig using artificial particles inseven density classes. All particles in a density class had essentially thesame density, size, and shape. Tests were conducted for particle systemsinvolving from two to seven components. Good agreement was obtainedbetween measured and modelled data to an extent that gave strongendorsement of the mathematical appropriateness of the core equation inthe King model. Somewhat ambiguous results were found with regard toclaims about the independencies of the single experimentally-determinedparameter required by the model.

Jan 1, 2015

By P. J. Rua

The Piedras Verdes copper mine is a new run-of-mine (ROM), heap leach, solvent-extraction/electrowinning (SX-EW) operation located 21 km (13 miles) north-northwest of the town of Alamos in the state of Sonora, Mexico. The Piedras Verdes copper mine is wholly owned by Frontera Copper Corp. (FCC), a Canadian corporation, through its 100 percent beneficial interest in Cobre del Mayo S.A. de C.V. (CDM), a Mexican registered company. The January 2008, minable reserves were estimated to be 193.6 Mt (213 million st) at a grade of 0.36 percent copper. The overall recovery of total copper was estimated to be 61.9 percent. The property has an additional 17-year life and is designed to produce 31.7 kt/a (70 million lbs/year) of cathode copper. Construction commenced in early October 2005. The first copper cathode was produced 12 months later at a total capital cost of $100 million. Elevations at the site range from 150 to 300 m (490 to 985 ft) above sea level. The area has excellent infra-structure in the form of towns, power, water, roads, rail, airfield and access to the deepwater port of Guaymas (Fig. 1). The surrounding area is also famous for its numerous polymetallic (lead, zinc, copper, silver and gold) epithermal veins. Some of these were mined for more than 200 years and provided the wealth on which the town of Alamos was built. The original village of Piedras Verdes was located in the area of the proposed openpit mine and, consequently, it was necessary to construct a new townsite 6 km (3.7 miles) to the south before project development could commence. The new town site (Fig. 2), complete with power and water supplies, roads, sewer system, schools, clinic and recreational facilities, was completed and occupied by 49 families in September 2005. CDM received its remaining permits from the Mexican environmental authorities on Sept. 20, 2005. This enabled the company to proceed with full-scale development. CDM owns or controls 27 mining concessions covering the resource. Surface rights to the Piedras Verdes project were controlled by four Ejidos (communal agrarian and/or ranching societies) and five individual landowners. CDM has acquired all surface rights necessary for its mining operations and associated facilities either through outright purchase or long term lease agreements.

Jan 1, 2008

By G. P. Holmes

"IntroductionThe copper-molybdenum property of Brenda Mines Ltd. is located 18 miles north west of Peachland in the Okanagan Valley of the Southern Central interior of British Columbia. The actual site is 50 miles north of the international boundary and 150 air miles east of Vancouver at an elevation of 5000 feet above sea level. The earliest written mention of the prospect is found in the Geological Survey of Canada, Memoir No. 243, issued in 1947 by Dr. H.M.A. Rice. In 1954 the area was staked by a prospector, Bob Bechtel, who interested Bern Brynelsen of Noranda Exploration in examining the claims. A joint Noranda - Kennecott program resulted but since the grades were so low the property was not taken up until in 1964 a re-examination by Chapman, Wood and Griswold produced recommendations leading to the construction of the Brenda Mine as it is today.The rounded, timber covered mountains of the area are composed of the tuffs, argillites and limestones of the Upper Triassic Nicola Group, which is intruded by a Jurassic quartz diorite, called the Brenda stock0 The actual orebody occurs in a strongly fractured zone within the Brenda stock, approximately 1500 feet from the contact with the Nicola group0 The ore minerals, .chalcopyrite and molybdenite, associated with pyrite and magnetite of lesser importance, occur as fillings within the fractures 0 The grade of the ore decreases outwards from a central higher grade core and in January 1971 total reserves were estimated at 165 million tons assaying 0,182% Copper and 0,049% Mo."

Jan 1, 1972

By S. E. Phillipson, P. L. Tyrna

Lineament analysis, a remote sensing application for geological structures, has been criticized for reliance on subjective interpretations. The Mine Safety & Health Administration’s Roof Control Division performs lineament analyses with a technique that removes much subjectivity. Study areas are viewed on satellite images with software that allows examination under artificial sun azimuths and elevations. Extraneous lineaments are removed through successive steps of superposition, resulting in selection of the most robust linear features. Field investigations revealed a strong coincidence of joint and fault zones that were parallel with projected lineaments. The Roof Control Division’s successful identification of lineaments associated with roof falls and highwall failures has prompted some mine managers to incorporate lineament analysis as a mine-planning tool. The identification of potentially hazardous ground conditions will allow mine operators to obviate safety concerns that might otherwise adversely affect miner health and safety.

Jan 1, 2002

By Jan E. Nesset, Antonio DiFeo, James A. Finch, Jose Hernandez-Aguilar, Cesar O. Gomez

"The gas dispersion measurement sensors and methodology developed by the mineral processing group at McGill University have to-date been employed at a number of plants in Canada, Australia, the U.S., South Africa and South America. In some cases the measurements have been directly linked with metallurgical performance while in others the gas dispersion surveys on their own have proved very useful in understanding the behaviour of the flotation cells. In addition to reviewing the current state of the gas dispersion measurement technology, the paper will present a series of case studies from the various plants and will show how this technology brings a remarkable new level of understanding to flotation behaviour. The influence of the bubble size distribution on recovery and grade are emphasized in the paper.INTRODUCTIONBackgroundThe advent of new sensors to characterize gas dispersion parameters in flotation cells is a development that is long overdue. While the chemistry of flotation has been studied since the early 1900’s, it is only now that the significance of bubble size distribution, gas rate and gas holdup can be meaningfully measured in-plant with robust and precise sensors. Early researchers, like T.A. Rickard (1916) recognized the importance of understanding the role of air and bubbles in flotation when he wrote in 1916 “we know that the key to the flotation process is to be found not in the oil, the acid, or the apparatus, but in the bubbles. The man who understands the mystery of a soap bubble has mastered the chief mystery of flotation”. In his 1999 review paper on The Froth Flotation Century D.W. Fuerstenau laments the fact that due to their “inert nature”, bubbles have never received their due attention from researchers who tended to focus on the chemical, physical, surface and colloidal aspects, rather than the physics of the process. It is perhaps fitting that now, 100 years after the inception of industrial flotation practice at Broken Hill, Australia, researchers and industry have turned their attention toward the importance of truly understanding the role of bubbles in flotation."

Jan 1, 2005

By R. Hummel

When the slope angles of the southern side of the Venetia open pit were required to be flattened by some 20 degrees after an analysis completed by De Beers geotechnical engineering in conjunction with SRK, the additional waste stripping tonnage generated was in the order of some 70 million tons. The potential cost of having to move this tonnage had a significantly negative effect on the Net Present Value of Venetia Mine, challenging the viability of the third pushback and rendering a potential fourth pushback completely uneconomic. This paper details some of the innovation that went into the design and planning process undertaken to virtually negate the instantaneous effect of the flattened slope angles and the associated waste tonnage as well as further improve the NPV of Venetia Mine and bring the fourth pushback back into economic viability. This process has become known as NPV+ and is anon going exercise in waste reduction/deferment and revenue advancement.

Jan 1, 2001

By R. M. Kear

Strategic and tactical planning are both required in the mining industry but have completely different objectives and require different environments. If these are not fully understood, then the best value for a mining operation may not be realized. This paper examines the differences in these approaches and how they interface in the mining environment. The objectives, content, skills required and the implied management issues for these two components are examined with the hope that this will assist management and the planning teams in defining their respective roles and expectations. The opinions are those of the author based on his experience on several mining operations and projects.

Jan 1, 2006