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By B. R. MacKay

Introduction The Corbin coalfield is one of the smallest, and at the same time one of the principal, producing bituminous-coal areas in southeastern British Columbia, and is unique on account of the great original thickness of one of its coal seams and the remarkable concentration of coal in a small area that has occurred through intense folding and faulting of the measures. These are such that the deposit has been referred to at times as "the world's thickest coal seam" and as" a mountain of coal." The determination of the number, thickness, and character of the seams present, and the structure, extent, and geological relationship of the several deposits, are of vital interest both to the operating company in its endeavour to evolve the most efficient method of mining these exceptionally thick deposits and to the Government in estimating the coal resources of the different fields. With the object of ascertaining these data the writer was assigned in 1930 to geologically map and study the Corbin coal deposit. A topographic map covering Coal mountain and the immediate vicinity on a scale of 1 inch =800 feet, with a contour interval of 25 feet, made by the Topographic Division of the Geological Survey, served as the base for the geological mapping.

Jan 1, 1931

By Chulgi Suk, Hoon Park, Hyonsoo Kim, Hakman Kim, Sangho Cho

Dust emission from blast demolition and other construction activities can be a nuisance; it is widely recognized that fine particles less than 10 µm in equivalent diameter (called PM10) may cause health problems. Mist spray systems, such as rain guns, sprinklers, water/surfactant sprays (or foams) etc., are some of the most effective dust suppression methods. A large amount of research has showed that when water droplets are produced in an equal amount to that of dust particles, the airborne dust is suppressed by the agglomeration of dust and mist particles. A method for generating micro-sized mist from water, achieved by the detonation of explosives in the water tube, was suggested and is called the ‘detonationdriven water bag burst system’. There are many experimentally observed limitations of the explosioninduced water break-up process. The water bag explosion tests were simulated using the AUTODYN software, in order to investigate the aerosolization mechanisms of the detonation-driven water and water break-up process into micron-sized droplets. As a result of the numerical analyses, the diffusion direction of water when detonating in the central interior part of water tube was radioactive and significantly stronger than when detonating in the bottom exterior part; this is due to the compressive flow of the volume change inside of the water tube, which resulted from the blasting wave inside of the tube, as well as the reflected pressure on the ground. Blast tests of full-scaled reinforced concrete columns were conducted to verify the effectiveness of the suggested detonation-driven water bag burst system. The water breakdown and dispersion that occurred while blasting the reinforced concrete columns were observed using a high-speed camera, and dust generation was monitored using four density detectors. The suggested detonation-driven water bag burst system showed that the average dust density decreased by up to 7 mg/m3.

Jan 1, 2016

The C.S.A. copper-lead-zinc mine, located 7 miles north of Cobar in central-western New South Wales, is the largest known mineral ocurrence in the Cobar mining field. The generally discordant orebodies occur within a strike width of 600 ft and an overall strike length of 1200 ft. They are enclosed by the steeply westdipping, west-facing sediments of the Cobar Group, and comprise lenticular steeply north-pitching and eastdipping zones of sulphide mineralization which range in composition from massive pyrite-sphalerite-pyrrhotitegalena to less massive pyrite-pyrrhotite-chalcopyrite varieties.The thinly bedded siltstones, shales, and greywackes enclosing the mineralization appear to have derived some of their constituents from volcanic sources. They have been metamorphosed to the greenschist facies of regional metamorphism. At least two stages of deformation and folding have occurred. The first stage folded the rocks on a south pitching fold axis into their present configuration, and superimposed a strong axial plane cleavage which subsequently guided the emplacement of the mineralization. The second stage of deformation is considered to have controlled the zonal distribution of the orebodies.

Jan 1, 1970

By Patrick Bermingham

This report presents the results of six STATNAMIC loading tests that were carried out on four different pile types at the CALTRANS 280 Test Site (Bridge No. 34-46) in conjunction with the Tension Pile Test Program. The STATNAMIC testing was performed by Berminghammer Corporation at the request of the California Department of Transportation, Office of Geotechnical Engineering. Others performed the static tension (uplift) and compression loading tests which werecarried out on the piles tested using the STATNAMIC method. A summary of the STATNAMIC test results is presented and discussed, and the appropriate results are compared with the static test results

Jan 1, 1993

By G. L. Oldwright, F. K. Shelton, W. E. Keck

"INTRODUCTION Zinc must be of high grade to satisfy the present demand. Even when the amount of premium paid is small, the purer metal as the buyers' preference. The following specifications for spelter were taken from the American Society for Testing Materials for 1927, Part I, pane 524. (The specifications for 1930, p. 582, are tile same.)Another specification for zinc of a much higher grade than any of the above has been established lately by the same society. The committee on zinc die-casting (Proc. Am. Soc. Test. Mat., vol. 31, 1931, p. 263) reached the following, conclusions: I. ""That the purest of zinc is necessary to produce stable zinc-base die castings, and as a result requested specifications for zinc spelter .with total impurities not over 0.02 percent."" Their tests showed that the die castings made of the purest zinc had the least elongation and the greatest tensile strength, and exhibited the least changes with temperature.Still more far-reaching claims are made for the properties of zinc containing over 99.99 percent metal. Zinc foil, for instance, may someday be made as a common commercial product. It would seem likely that the demand for zinc of high grades rill continue and that even purer varieties may be desired. This demand fits in with the modern trend in manufacturing plants of reducing the number of variables to a minimum by using pure materials, and of controlling the processing of metals during their various stages of fabrication by mechanical means instead of by expert laborers."

Jun 1, 1933

When perusing articles which treat of mining geology, and when talking with miners on the field, one is at times unable to follow the exact thoughts intended to be expressed, owing to the introduction of occasional technical words, the meanings of which are not thoroughly understood either by the speaker or by the hearer, or possibly by both and laymen at times accuse their technical brethren of attempting to confuse them by employing unusual words in their conversations and writings. Technical words are necessary adjuncts to all arts and sciences. They creep into our language, frequently unnoticed by those who employ them, as being more concise and convenient than longer sentences to explain frequently recurring expressions. In many cases these words give the finest shades of meaning, such as aglomerate and congzomerate, but in others they are extremely ambiguous, for instance black sand, which in some places means ilmenite, in others, chromite, tourmaline, cassiterite, in fact, any black mineral occurring in the form of sand. Then, again, much confusion is cansed by the same rock or mineral having different names, e.g, jlu01'spa'i', which is known as cand, cann, cauk, kawk, blue-John, Derbyshire spar, &c. The multiplicity of local names is of course chiefly found among the more common minerals, which are widely distributed some people have a propensity for using words the meanings of which they understand as little as' they do how to pronounce them. We have heard such persons speak 'of vughs as "bugs," and oxides as "ox hides," and to show that there was no mistake in their intentions, we have seen these and other words written in the same way as they were pronounced. Then, again, some persons, relying more on examples than definitions, get a very vague idea as to what the true meaning of a term may be the word dimite is an example in point, which we have frequently heard applied to any dyke rock that the miner was unable to recognise as granite in fact, he uses the word in a general sense, just as the field geologist provisionally employs the word " greenstone " for certain rocks, until he has an opportunity of thoroughly investigating their character.

By Peter Jackson

The dewatering of the large construction pits required for major infrastructure projects often has a significant impact on the environment. This is particularly so in urban areas and where groundwater resources are of interest. These environmental impacts are inter alia, groundwater lowering and the consequent effects such as settlement and deterioration of timber foundations, together with the impact of the dewatering on the groundwater quality. In order to minimise the environmental impact of the dewatering, the quantity of water to be abstracted and the amount of groundwater lowering in the surrounding area must be minimised. This paper describes the measures that have been taken on the Copenhagen metro project to achieve the objective of minimal environmental impact whilst still carrying out a major dewatering scheme.

Jan 1, 2000

By John Sleavin

As part of the Link Light Rail project in Seattle, WA, work was completed at the Pine Street Stub Tunnel (PSST) in early 2007 for the Central Link project. This tunnel was excavated using cut-and-cover construction within the limits of Pine Street. The stub tunnel provides a turn back via double crossover for light rail trains running in the Downtown Transit Tunnel (DTT), as well as a connection point for the next phase of the project, the University Link (Fig. 1). Designing the new University Link tunnel connection to the existing PSST was a tricky task. The on-site geotechnical conditions, buried obstructions, geometry, requirements for construction and balancing operational considerations and neighborhood stakeholder concerns associated with the recently completed PSST combined to create a uniquely challenging assignment.

Jan 1, 2010

Analysing a flotation plant?s operating performance requires accurate metallurgical sampling. Typically, the aims of performing flotation plant surveys are to establish a consistent and accurate understanding of the operation of the circuit as well as to identify potential areas for improvement. Once the data have been collected, a mass balance is required to provide a consistent set of data from which plant performance can be assessed. Mass balancing is a key skill that many metallurgists and mining industry professionals are familiar with. Mass balancing reconciles the feed and product streams throughout the plant and is sometimes used for accounting of the material entering and leaving a system (eg. JKMetAccount). However more common reasons for mass balancing are: better understanding of the flowrates within a system, assessing the quality of data obtained from sampling and surveys, and providing a key dataset for assessing and improving the performance of unit operations. Mass balancing requires practice and experience to determine if the results are reasonable. There are various software programs available to assist in the mass balancing and understanding of processing plants. This paper is focused on JKMultiBal initially developed by Gay (1993), and then later commercialized by JKTech. JKMultiBal in its current release is for balancing data in both one and two dimensions, i.e. balancing data on either sized or assay bases as well as size-by-assay. With the recent trend in flotation circuits becoming more complex, JKMultiBal has been used to gain a better understanding of the processes occurring within the circuit. This paper provides a description of the program as well as several case studies where the two-dimensional mass balancing has resulted in improvements in plant performance.

Jan 1, 2009

By K. G. Kebkal, R. Bannasch

"Because the operation of tethered underwater vehicles in the deep ocean or under drifting ice areas is very complicated or impossible, the application of autonomous underwater vehicles (AUV) is preferred or even the only possible solution. However, this implies the possibility of a direct and real-time control over all AUV functions, which is only achievable with the availability of accurate positioning/navigation and a high-speed communication link. This paper presents a flexible bottom- or surface-based solution enabling high positioning accuracy of underwater objects (harvester, AUVs, bottom nodes); specifically, a multifunctional system that combines Ultra Short Baseline (USBL) transceivers and Long BaseLine (LBL) stations deployed at a large depth. Moreover, each baseline transponder is equipped with a high-speed communication device to provide the means for real-time AUV control based on the information about its current position, e.g. navigate it with direct commands and operating its actuators and other mechanisms. Moreover a communication link with a high data rate can provide valuable visual information from the operation area.Depending on how many nodes the LBL grid comprise has, target transponder positions can be estimated with an accuracy of several to tens of centimetres. The purpose of the paper is to present the experiments with all key elements of the multifunctional Hydro-Acoustic USBL-aided LBL Positioning and Communication System."

Sep 1, 2014

By Grant R. Brown

The report provides guidance for determining those environmental impacts associated with the surface mining of steeply pitching coal seams. In addition to the environmental impacts, four additional issues are addressed, namely (1) Time and motion studies of those coal mining systems employed in mining seams which pitch in excess of 250, (2) Assessment of those mining techniques, (3) Development of rationale for the mining methods employed, (4) Identification of the reclamation practices and determine whether these practices were in compliance with appropriate Federal and State regulations. Five surface mines located in three geologically distinct basins of the United States were analyzed during the period of August through November 1979. The three basins include the Hanna Basin of Wyoming, the North Park Basin of Colorado and the Southern Anthracite Field of Pennsylvania.

Jan 1, 1980

"An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation.Low-sulfidation epithermal gold mineralisation at Ridge Mountain occurs within the Oligocene to Miocene volcanic rocks comprising andesite, porphyritic dacite and diatreme breccia. A diatreme breccia complex with a NE–SW elongated orientation covers an area of 3.0 × 1.7 km. Four main stages of mineralisation were identified, comprising: E–W- to NW–SE-trending quartz-chalcedony veins with disseminated pyrite, chalcopyrite and gold. N–S- to NNE–SSW-trending breccia veins with quartz matrix and disseminated pyrite and accessory sphalerite, galena, chalcopyrite and gold. NE–SW-trending quartz and calcite veins with disseminated pyrite and accessory sphalerite, galena, chalcopyrite and gold. ESE–WNW- to ENE–WSW-trending quartz veins with disseminated pyrite. This stage is only mineralisation that is hosted by diatreme breccia and clearly postdates.Quartz veins of the first, third and fourth stage are less than 2 m wide. Only breccia veins of the second stage are up to 10 m wide. Gold is present in all stages as microscopic inclusions in quartz and sporadically in pyrite. Macroscopic gold can be seen in the first and second mineralisation stages. Gold commonly occurs in association with sphalerite, galena and chalcopyrite in the second and third mineralisation stages.CITATION:Kucera, J, 2015. Diatreme breccia-hosted epithermal gold deposit at Ridge Mountain, eastern Mindanao, Philippines, in Proceedings PACRIM 2015 Congress, pp 587–592 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 18, 2015

By Leigh J. Wardle

This paper describes a numerical method for calculating the three¬-dimensional stresses and displacements induced by tabular excavations in a rock mass consisting of parallel layers of distinct material properties. The method is based on the superposition of numerical solutions for elementary displacement discontinuities in a parallel layered rock mass. The method can be used to analyse complicated excavation layouts such as those encountered in room-and-pillar or longwall mining. The method can automatically take into account the effect of the earth's surface. The method offers an economic and efficient solution to stress analysis problems which cannot be adequately modelled using two¬-dimensional methods and for which the expense of three-dimensional finite element or general boundary element analysis cannot be justified.

Jan 1, 1984

By A. Robles-Vega

In recent years, tellurium has been extensively used in the manufacture of semiconductor materials. For this type of application, high-purity tellurium is required. Selenium, lead and silicon are usually the main impurities in tellurium. During the electrolytic refining of copper, tellurium gold and silver are collected in the anode slimes. A pyrometallurgical treatment is used to recover gold and silver from the decopperized anode slimes whereas tellurium is oxidized and skimmed off from the refining furnace as a Na2CO3-based slag. In the slag, tellurium is present as sodium tellurite (Na2TeO3), which is further water-leached from the slag. The first step in the conventional process for tellurium recovery consists of the precipitation of the tellurium contained in the leaching solution as tellurium dioxide (TeO2). The solid TeO2 is then dissolved under acidic conditions for its further reduction with sulfur dioxide gas (SO2). In this paper, an alternative route for tellurium production is presented in which a sodium tellurate [Na2TeO4] intermediate is obtained by oxidation of the sodium tellurite in an alkaline solution following the water leaching step. Sodium tellurate is then dissolved in acid media and high-purity tellurium is obtained by reduction with SO2 gas. Experimental tests under laboratory conditions indicate that the novel process yields higher precipitation selectivity for tellurium than the conventional process. A comparison of its efficiency concerning impurities co-precipitation with respect to the conventional process is discussed.

Jan 1, 2009

"1.0 INTRODUCTIONThese Guidelines reflect the state-of-the-practice of the Deep Mixing Method (DMM) in North America. DMM is an in situ mixing process that breaks down the soil structure; injects binders, fillers and reagents into the soil; and blends them with the soil. DMM is also commonly referred to as Soil Mixing. The final properties of the treated soil in situ are a function of the composition of the native soils and groundwater, the binders introduced, the mixing methods and energy, and the conditions and time of curing. Treated soils generally have increased strength and stiffness and/or reduced permeability relative to the native soils.This document addresses DMM performed by rotating single and multiple axis mixing tools, rotating cutter wheels at the end of a rigid kelly bar, or trench mixing using a rotating cutting/mixing chain around the perimeter of a rigid bar. Binder may be injected through low or high energy (velocity) jets.The treated soils created through wet DMM are heterogeneous mixtures of binder, water, soil, and groundwater. Treated soils produced by dry DMM techniques are a mixture of binder, soil, and the water already present in the native soil.DMM applications described in this document include•,Earth retention•,Liquefaction mitigation•,Groundwater seepage control and containment isolation•,Bearing capacity improvement•,Deep foundations•,Mass stabilization and contamination containment•,Embankment, levee and dam strengthening, and stabilization•,Casing replacementThis document was developed to address deep foundations applications. Use of deep mixing for seepage control is not specifically addressed. The reader is referred to documents prepared by the U.S. Army Corps of Engineers for additional information. Shallow soil mixing and the use of DMM for stabilization/solidification of contaminated soils performed at depths less than 10 feet (3 m) are mentioned briefly. Jet grouting is not covered by these guidelines."

Jan 1, 2016

The concentration of Mt. Morgan sulphide ore has always been attended by serious loss of gold. Until recently, with a simple selective flotation flowsheet, even the lowest grade of ore milled-about 2 dwt. per long ton-thislloss was 0·9 dwt., whilst for average to high-grade ore, 3·5 to 5 dwt., the figure was 1·5 to 2·0 dwt. Early in 1937 it was decided to equip the research laboratory for an investigation into the condition and location of the escaping gold and the physical and mineralogical barriers preventing its recovery.With the completion of: this equipment in July 1937, trial and error testing, which had been explored to exhaustion, was abandoned and a five months' research programme mapped out and commenced. Based on the knowledge so gained, a flowsheet combining primary desliming, bulk flotation of the natural slime, selective flotation of the deslimed fraction, and cyanidation of the selective flotation tailing was drafted and tried with encouraging results in a 70-lb. per hour pilot plant. This flowsheet, modified to meet current circumstances, is being dove-tailed into the existing 1,500-ton sulphide ore concentrator, though the cyanidation treatment is actually carried out in the oxidized ore mill, to which the flotation tails are pumped.RESEARCH EQUIPMENT(1) Five tube elutriator (Fig. 1) t built in the company's workshop.

Jan 1, 1939

By C. E. Julihn

In the fall of 1933 a new discovery of gold was made in the old Mojave mining district of California about 70 miles north of Los Angeles. It led to mining operations that have surpassed in their results all reasonable expectations and are of exceptional promise for the future. In less than 3 years, exploration has opened up a number of veins, from some of which a substantial amount of high-grade ore has been shipped, while a large tonnage of milling ore has been disclosed. Two mills, operating on ore averaging better than $12 a ton, will probably produce more than a million dollars worth of gold in 1936, and a considerable increase of their output in the following year is anticipated. While continuance of these operations for a number of years is already assured by ample reserves of ore, future discoveries of still other veins are reasonably possible, as occurrence of gold throughout the volcanic rocks of the district is widespread and the veins now being mined showed little to attract attention at the surface.

Jan 1, 1937

By D. L. H. Bulbring

The removal of a cylindrical core from thick-wall sections for creep analysis by the relatively new Weldcore® process represents a very exciting methodology for obtaining more representative creep damage data from large engineering structures. The cylindrical core that is removed, representing about 60% of the wall thickness, leaves a substantial removal site that needs to be repaired. This paper presents data pertaining to taper Friction Hydro Pillar Processing as an alternative repair technique for filling the core removal site. Process parameters were evaluated with special attention being paid to the effect of downward force on process response variables, weld defects, and mechanical properties of 10CrMo910 steel. Process temperature and torque response as well as total process energy input were also considered. This paper also assesses the static and dynamic performance of this repair technique. The influence of a varying downward force and the occurrence and position of discontinuities were quantified. Downward force was shown to have the most notable effect on weld joint dynamic performance and was found to be related to the process temperatures achieved in close proximity to the weld interface.

Jan 1, 2013

By Richard Dahl, Richard P. Taylor, David H. Watkinson

"Abstract - Detailed mapping of the Eastern Gabbro, Coldwell Complex, Ontario, revealed that the copper and platinum-group-element deposit on the Marathon property is confined to a coarsegrained to pegmatitic gabbro-diorite intrusion, the Two Duck Lake intrusion (TDLI). Exposed along the eastern boundary of the Coldwell Complex, the TDLI was emplaced as a sill whose orientation is slightly oblique to the general structure of the Eastern Gabbro. The TDLI has been subdivided into lower, middle and upper sub-units on the bases of lithological, textural, mineralogical, and geochemical criteria. Both border sub-units are sulfide-, base- and precious metal-enriched, and exhibit abundant evidence of host-rock assimilation. The primary mineral assemblage in the TDLI is plagioclase, olivine, clinopyroxene, Fe-Ti oxides, with accessory orthopyroxene, biotite, apatite; this primary mineral assemblage is essentially preserved in the core of the intrusion (i.e., the middle subunit). The Cu-PGE Marathon deposit, delineated mainly in the upper sub-unit of the intrusion, consists of disseminated Fe-Cu-Ni sulfides, and platinum-group-minerals derived by hydrothermal remobilization from primary magmatic sulfides. Enrichment in Cu and PGE resulted from partial replacement of original Fe-Ti oxides and pyrrhotite in the primary mineral assemblage by reaction with (a) residual magmatic fluid, and (b) fluids derived from the breakdown of host rock xenoliths and hydrothermal alteration along the lower contact of the TDLI. Résumé - La cartographie détaillée de l’Eastern Gabbro, Complexe Coldwell, en Ontario, révèle que le gisement de cuivre et éléments du groupe du platine de Marathon est confiné à une intrusion gabbro-dioritique, de grain grossier à pegmatitique, l’intrusion Two Duck Lake (TDLI). Cette intrusion s’est mise en place sous la forme d’un filon-couche légèrement discordant sur la structure de la bordure orientale de l’Eastern Gabbro. On y distingue trois sous-unités, inférieure, centrale et supérieure, sur la base de zonations lithologique, minéralogique et géochimique. Les sous-unités marginales sont enrichies en sulfures, métaux usuels et précieux, et montrent de nombreux indices d’assimilation des roches hôtes. La paragenèse minérale primaire inclut le plagioclase, l’olivine, le clinopyroxène, les oxydes ferro-titanés et accessoirement et localement, l’orthopyroxène, la biotite et l’apatite : cet assemblage est surtout préservé au coeur de l’intrusion (sous-unité centrale). Le gisement de Cu-EGP de Marathon, situé principalement dans la sous-unité supérieure, comprend une minéralisation disséminées à sulfures de fer, cuivre, nickel, et minéraux du groupe du platine, dérivés de sulfures magmatiques primaires par remobilisation hydrothermale. L’enrichissement en Cu et EGP résulte du remplacement d’oxydes ferro-titanés primaires par réaction avec des fluides tardi-magmatiques, et des fluides assimilés le long de la bordure inférieure de l’intrusion, dérivés de la fusion partielle des xénolites et de remobilisations hydrothermales."

Jan 1, 2001

By A. J. Vietti

A pilot plant paste thickening campaign was conducted at the Anglo Platinum Limited Mogalakwena South Concentrator plant in South Africa in order to determine the water saving capability of P&TT technology. In the process a simple water consumption model was developed for estimating the overall water consumption of the mine. The model indicates that for the Mogalakwena tailings, significant water savings are achieved by discharging thickened tailing directly to the TSF but only at densities where free water release at the TSF is close to zero. Keywords Paste, thickened tailings, thickener, water savings, water consumption.

Jan 1, 2011