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So many emergencies that crop up in mining necessitate a departure from ordinary methods that the writer has been led to illustrate a few of the examples that have come under his notice during a somewhat lengthy career; and as most of the methods illustrated are certainly outside the ordinary, it may be hoped that while to many they may convey little that is new, to the larger number some acceptable information may be gleaned whenever the occasion calls for it. Experience has shown that there can be no hard and fast rule in mine timbering that will fit the varying- necessities of different localities, and the engineer must divest his mind of all prejudices that his practice of any particular system or systems may have induced, and must direct his attention to the character of the local timber and its fitness or otherwise for the purpose he has in view. Fortunate indeed are the man and mine that can claim an abundance of good and cheap mining timber it simplifies, oftentimes, what would be, under unfavourable timber conditions, a difficult problem. In many parts of the States there is either none or at best a scrub if the latter, he has to either pigstye, balk, or bulkhead, if his ground will permit; if, not, and the necessary timber has to be imported, then some system of recovering his timber and using it over and over again may be possible. As an illustration of this, Fig-s. Nos. I and 2 show a method applied to the copper deposits of the LyellTharsis, Tasmania. The workings were wide; varying from 30 ft. to 50 ft., and the deposit a taIcose schist of fairly good...

Jan 1, 1902

By Peter Faust

The foundations for the new South Viaduct Bridge in San Francisco were extremely challenging due to the requirement for very large and deep piles installed adjacent to historic structures. Drilled shafts up to 12? foot in diameter were constructed to a maximum depth of 200? feet in alluvial soils and Franciscan Bedrock using an oscillator system for the installation of the permanent steel casing. This paper provides an overview of the construction techniques, the equipment, and the challenges associated with constructing 12? foot diameter shafts on this very complex project in one of the nation?s nicest landscape setting.

Jan 1, 2011

At the treatment plant of the Broken Hill South Limited, Broken Hill, the zinc concentrates, with water, are pumped out to a more or less level area, and stored in dams to dry by drainage and evaporation.In-the construction of these dams a clay bank is first thrown up around the proposed dam site. The concentrate and water mixture are then run in from the perimeter, the solids being continuously shovelled up to increase the bank height, while the clear water is drained off at the centre and returned to the treatment plant.These dams vary in size up to 57,000 sq. ft. in area; when completed the banks are about 12 it. high, and the capacity for the largest dams is about 350,000 cub. ft., say, 20,000 tons.The survey office is called upon for a monthly survey of these dams, generally three of which are in process of building or refilling. The puggy nature of the material prohibits walking beyond the bank of the dam, therefore the following method of estimating concentrates was evolved. No originality is claimed, but as the need is for a true survey, and the results have shown the accuracy of the method, a description is warranted. The dam site is first laid out into 10-ft. squares with a theodoliteand 150-ft. steel tape, the outside lines being placed about 15 ft. from the clay bank - 15 ft. is the maximum convenient distance from the bank for working with the levelling staff mentioned later.As the dam is rarely rectangular in plan, the outside points pegged out are not always the corner of a square, but are placed to give the greatest convenience in later work, that is to say, there may be triangles and irregular figures. The plan (Fig. 1) and photographs (Figs. 5 and 6) will give the general idea of the layout. At each point is driven a 3 ft. 6 in. round iron peg about 3 ft. into the ground. This peg is to permanently mark the point, and is not liable to be...

Jan 1, 1925

By J A. Rabe, PAP Fouche, K O?Neill

Two of the most important issues mines have to deal with are tracking the ore mined from pit to plant and to test the efficiency of beneficiation equipment. Kumba Resources and Saco Systems are working together at moment to develop a RFID tracer system to help address these issues. This paper will focus on the tracking of ore from pit to plant. The main advantages for ore tracking is to ensure plant feed blending and dilution according to plan. The RFID tracer system works on the basis of a tracer that physically simulates the ore properties and radio frequency technology that facilitates communication with the tracer and allowing information to be stored on the tracer. This paper tends to indicate the progress on the application of RFID tracer technology in the minerals processing environment as tested at Kumba Resources so far. It is concluded that the system has great potential, but some important problems remain

Jan 1, 2005

By Milton Camino Ramos

MARSA forma parte de los yacimientos vetiformes de la franja metalogenética aurífera del Batolito de Pataz, y políticamente se encuentra ubicado en la provincia de Pataz, La Libertad. En este sentido, el presente texto describe los resultados del programa de exploración 2010-2011, donde se dio el descubrimiento del primer cuerpo mineralizado del yacimiento, el cuerpo Esperanza, entre otras ocurrencias. Asimismo, se muestra que los cuerpos mineralizados de la franja metalogenética de Pataz, se formarian en estructuras de primer orden con evidencias de reactivacion, cuyo sistema estructural funciona como entrampamiento y en varias etapas de mineralizacion.

Sep 12, 2011

The problem of ventilating an advancing drive which finally reached 5,550 ft from the fresh air base in rock with virgin temperature of 83°F was solved economically by the use of two 15 h.p. electric fans forcing ventilating air through 281/2 in. dia. fiexible polythene tubing of wall thickness 0·010 in. The saving in cost over conventional metal duct was estimated to be £3· 24 per ft of drive.INTRODUCTIONAs described by Dutton (1965) and Newton (1965) the existing 1,480' ft level drive at the South Mine, Broken Hill, was extended in two stages. The first extension was 3,790 ft, the face then being 4,790 ft from the fresh air inlet. Later, after a vertical ventilation connection was made 1,000 ft back from the face, the drive was extended a further 4,550 ft. The rate of face advance in both stages was about 15 ft per day (3 shifts of 5 ft), 5 days per week. Drive size was 8 ft by 9 ft 6 in. high.The Mines Inspection Act of New South Wales requires 6 hr shifts (instead of the normal 7 in Broken Hill) to be worked if the wet bulb temperature exceeds 80°F. Virgin rock temperature on the 1,480 ft level was 83°F. Inlet air temperature varied with seasons from 58 to 72,oF wet bulb.To adequately ventilate the face, a flow of air of about 11,000 c.f.m. was thought to be necessary.Re-entry time was about 75 min, being governed by the 7 hr length of shift (3 shifts per day) and travelling time.Blasting was permitted only at the end of the shift, in accordance with local industrial restrictions.

Jan 1, 1965

In, one stage of the purification sequence of the zinc sulphate electrolyte used at Risdon, cobalt is, precipitated as cobalt nitroso-,B-naphtholate, which is separated from the solution by filtration. Owing to the method of conducting the purification the filter cake contains much gypsum, unconsumed calcium hydroxide, basic zinc sulphate, and entrained zinc sulphate solution, Small amounts of iron and copper that have escaped previous purification steps are also precipitated with the cobalt as nitroso-,B-naphtholate. Thisprecipitate, normally carrying about 18% cobalt, is the raw material for the production of cobalt oxide, cobalt sulphate and cobalt metal.COBALT OXIDEThe main problem in the preparation of a reasonable grade of cobalt oxide from the filter cake is the economic separation ,of the cobalt nitroso-,B-naphtholate from the gypsum. This was solved by the application of flotation. It was discovered that the cobalt nitroso-,B-naphtholate, under correct conditions, would float without any addition agent, giving a relatively high grade concentrate. A plant, was built and has been in operation since 1936. The filter cake is pulped with water and pumped to one of two mechanically agitated tanks, eath capable of holding one day's output. Sulphuric acid is added until the free acid concentration reaches about 3 gm. per litre. Basic zinc sulphate is dissolved and calcium hydroxide converted to gypsum. The pulp, carrying about 2t lb. of solids per gallon, is pumped at a suitable rate to the first of a series of 10 flotation, boxes.. Each box is 3 ft. by 2 ft. 9 in. by 5 ft. deep, and, all have a common, pulp level, since the...

Jan 1, 1949

By Tae-kyeong Yeu, Jong-Choi, Cheon-Hong Min, Hyung-woo Kim, Jae- Won Oh, Sup Hong, Minuk Lee, Sung-Soon Kim, Chang-Ho Lee, Ki-Young Seong

"Collecting mineral resources from the seabed using a seafloor crawling robot is the firststep in the mining operation. The second-step is lifting the collected ore up to the water surface. For lifting through a riser pipe, prevention of pipe clogging (flow assurance) and economic and eco-friendly up-transferring is of the utmost concern.During collection of mineral ores, the production rate can be highly variable because of the variability in the distribution of the mineral deposit, variations in seafloor topography, fluctuations robot speed, and variations in performance of the mining robot, etc. Direct transfer of the collected ore to the riser pipe might cause unpredictable and serious problems such as over-loading of the lift pump, reduction in the life of the equipment, pipe clogging, severe increase of down-time, critical damage of equipment, further propagation of damages, and total failure after all.As a counter measure to these potential problems, a buffer station has been adopted, which is capable of storing the collected ore for a certain time and simultaneously regulating the transfer of the ore into the riser pipe. A pilot buffer has been developed by KRISO/KIOST (see Fig. 1)."

Sep 1, 2014

By James A. Madonna

Several universities and colleges in Australia, Canada and the United States, recognized the need to establish or reorganize geoscience programs at the vocational and two-year technical levels. To accomplish this, a cooperative study with industry in one state or province from each country was initiated. These include Tasmania in Australia, British Columbia in Canada and Alaska in the United States. The objective of this work was to develop a diversified geoscience educational model at the two-year technical, vocational and continuing education level that provides the source from which any nation can draw the proper educational tools to create a new geoscience program, modernize an existing program or strengthen a weak program. More than 100 mineral industry organizations provided information regarding their specific training needs for support personnel. The data gathered have been used to identify training areas for semi-skilled, skilled and technical personnel in geochemical mineral exploration. These included geological, geochemical, environmental and computer skills. With the areas of major educational need defined for geochemical exploration, an educational field skills model was developed for the three levels of training. The international need for a study of this type was recognized as early as 1980, following numerous contacts from domestic and foreign geoscience educators regarding the structure and success of training within the University of Alaska Fairbanks Mining Extension program, located in Fairbanks. Contacts, correspondence and visits included educators from Australia, Brazil, Canada, Mozambique and the conterminous United States. The need was magnified between 1985 and 1989 at the University of Alaska Fairbanks, when an attempt failed at initiating and developing a two-year geoscience vocational-technology program leading to an Associate of Science degree.

Jan 1, 1994

By Fulton Flick

THE micrography and macrography of aluminum and its alloys present certain difficulties. Many of the difficulties attendant on the micrography have been removed by methods developed during the past few years, notably those of E. H. Dix, Jr.1 The development of grain size in aluminum and its alloys may be equally troublesome, yet comparatively little detailed attention appears to have been given to it. Satisfactory reagents. are available for the development of such structures in ferrous and most non-ferrous metals, but those applied to aluminum and its alloys, i. e., alcoholic or aqueous solutions of sodium hydroxide or hydrofluoric acid are not entirely satisfactory. Hanson and Archbutt,2 in speaking of these two reagents, state that "These two reagents give fairly satisfactory results, but they sometimes produce badly tarnished surfaces from which the surface deposit is difficult to remove." It has been our experience that neither of these reagents is to be entirely relied on for developing structures suitable for study or photography. This means that when the etch fails to produce satisfactory results the, specimen must be repolished, through the 000-paper at least, and then etched with another reagent. This procedure entails a con¬siderable loss of time, and the final results may not be all that might be desired. However, the reagent to be described, although not a panacea for all etching troubles, has improved results so markedly that it is felt that it is worth offering as a grain-size etch generally applicable to aluminum and aluminum alloys. Czochralski3 in 1915 mentioned the application of a solution of 10 to 20 c. c. concentrated hydrofluoric acid in 100 c.c. absolute alcohol, etching in this reagent being followed by dipping in concentrated hydrochloric-acid solution.

Jan 2, 1925

By Braden Lusk, Paul Sainato, Josh Calnan, Hiago Vasconcelos, Luis Felipe Marinho

"Blasting and rock fragmentation is one the most important unit operations in mining. Since itsintroduction into the mine production cycle, mining has become more efficient in mineral production(Hartman, 2002). Widely used with the main objective of breaking rock mass in smaller fragments to be loaded and hauled at a minimum cost, blasting is optimized when stemming materials properly confine drillholes charged with explosives. Halim Cevizci (2013) performed a stemming application using Gypsum plaster, a kind of material that exhibits solid-like behavior when it is dry. Based on his theory, the present article reports an experiment using another type of material that shows similar behavior, non-Newtonian fluids. The primary goal of this study is to measure the confinement effectiveness provided by a non-Newtonian mixture as the stemming component. The study also analyzes the explosives’ energy propagation throughout the rock mass relating to the stemming materials applied. Currently, mining literature recommends the application of dry granular materials in stemming columns, because of its inertial and high frictional effects (Hagan, 1973). However, the test verified that the mixture added to the stemming column was able to reduce energy and gas losses to the atmosphere, because of the liquid’s property of filling voids in the material. The solid-like behavior of the non-Newtonian mixture was investigated for its capability to improve borehole confinement, since the mixture reacts like a solid when under shear stress. The results were compared to those from sand and air stemming applications, configured in different arrangements. It was concluded that the non-Newtonian mixture yielded high results due to its better confinement effectiveness, a reduction of air overpressure, and an increase of the strain propagation and ground vibration throughout the rock."

Jan 1, 2016

By Takashi Saito

Since early 1970?s skirt suction foundations (skirted foundation / bucket foundation) have been used as support for large fixed substructures or anchors for floating structures in offshore hydrocarbon development projects. In recent years skirt suction foundations are recognized as one of the solutions in foundations applicable to bridge substructures installed in waters, because skirt foundations have a wide variety of functions such as control of settlement during service life, less impact to environments during operation at installation site. This paper introduces general features of skirt suction foundations, and then discusses design practice of them for the application to bridge substructures, with reference to experiments in both laboratory and field.

Jan 1, 2013

By Paul J. Ehret

With the passage of the Surface Mining Control and Reclamation Act (SMCRA), and the implementation of state permanent programs, underground coal mining operations are for the first time subject to government regulations regarding subsidence. These regulations now and in the future will directly affect the manner in which mining companies mine their coal. Since the promulgation of the original final regulations by OSM, numerous changes in those regulations have been made and many additional changes are pending in the near future. This paper will discuss state and federal approaches to regulating underground coal mines and examine issues surrounding future subsidence regulations.

Jan 1, 1986

By R. N. Zitter

PRESENT work was done in connection with a program for obtaining a low energy gap semiconductor suitable for photodetection. The inter-metallic compound InSb, which is now being in-

Jan 1, 1959

By John J. Murray, Michael T. McRae, Michael A. Krulc, Kathy L. Schuler

The San Vicente Pipeline Tunnel Project involves the construction of an 8.5-foot-diameter water pipeline in an 11 mile tunnel in San Diego, California. The tunnel is located in extremely variable geologic conditions of strong granitic and volcanic rocks, weak sedimentary rocks, abrasive conglomerates, and mixed face conditions. One reach of the tunnel is a 5,200-foot mixed face reach that includes Friars Formation Conglomerate overlying granitic rock. Due to the variable ground conditions in this reach, the use of a TBM was deemed too risky and the contract documents required drill-and-blast and hand mining methods. Although it was not required, the contractor elected to construct this reach using NATM methods. This paper describes the geology of the 5,200-foot mixed-face reach, the design evaluation, and the construction challenges faced on this project.

Jan 1, 2007

By D. Hoffmann, S. Plumb

IRUP is an iron-rich ultramafic pegmatite rock that formed due to hot ironrich fluids and gases replacing local stratigraphic zones of the Bushveld Complex. This study focuses on the estimation of the probability of IRUP occurrence on the Merensky Reef at the Marikana Karee Mine. A 2.15 million centare IRUP-rich domain at the Karee Mine was initially defined from the interpretation of a surface aeromagnetic anomaly, and exposures in the mine workings. Surface boreholes (spaced 250-500 m apart) within this IRUP domain contain approximately equal numbers of IRUP-replaced and IRUP-free intersections. Owing to the uncertainty in the continuity of the IRUP alteration (a result of the wide borehole spacing), the risk associated with the development of mining infrastructure within this domain is unquantifiable. Semi-quantitative data comprising visual estimates of IRUP replacement from reef development mapping data and surface borehole reef intersections was interpolated into blocks using indicator kriging estimation. Comparative analyses of the estimate of IRUP occurrences were made by changing the block size and declustering the data systematically. Reconciliations of the probability of IRUP predicted from the block models derived from the different data-sets and sequential indicator simulation models were analysed for four mining study blocks. A quantitative approach to modelling the occurrence of IRUP can be an additional tool for refining the estimate of the geological losses that inform the mine plan in such high-risk zones.

Jan 1, 2015

Over recent years the trend in Australia has been towards the definitions of sustainable development which emerged from the 1992 Rio Summit of retaining a commitment to ecological integrity, but also incorporating social and economic dimensions of sustainability. Sustainable development may be seen as maintaining and enhancing:natural capital: defined as all natural resources, both environmental and those of traditional economic value; manufactured capital: made by human kind; including produced goods, infrastructure and built environment; human capital: defined as the health, well-being, intellectual capabilities and spiritual welfare of individuals; and social capital: defined as social relations and institutions within and between societies, their norms and functionality (Ameef, 2002). This paper will endeavour to assess the challenges and opportunities facing the professionals and their Institute in the minerals industry in Australia because the MMSD Global and Regional Australia Reports do not, in the authorÆs opinion, adequately address the æhuman capitalÆ input into the current or future development of the minerals industry, in particular, the sustainability of the professionalsÆ skills, knowledge and experiences in a global context.

Jan 1, 2002

By Arpit Parikh

"Ground Water or Pore water pressure development in Sandy Soil formation is Critical situation in foundation analysis and design.Moreover it become severe while associated with higher liquefaction probability in river bank areas. It is difficult to find cost optimized solution for liquefaction mitigation under limited budget allocated for the project. Here in these research paper the attempt has been made to have clear picture of liquefaction by using various techniques and field tests. And its mitigation by suitable foundation type. In Bangladesh, On Bank of River Meghana, Power plant structures are proposed. The particular site is full of fine sand having partial silt throughout from EGL to 55 m depth. Hence in addition to Conventional Boring / Drilling operations, CPLT, SCPT, SCHT and PMT had been performed to arrive deterministic effect of liquefaction. By use of Geologismiki software and some excel based programs developed which indicates that Certainly liquefaction occurs under the event of earthquake. By Checking past records of Bangladesh we found, there are small magnitude earthquakes are inevitable and frequent. Hence fourth to overcome the bad effect of liquefaction, the deep pile foundation -Driven Pre Cast Solid Square Pile of 400 mm dia. had been suggested for various types of power plant structures. Which densify the soil and ground will improve in resisting liquefaction.1. INTRODUCTIONA Detailed Geotechnical/Foundation design Analysis had been done to arrive at optimum foundation design solution in highly probable liquefaction zone of Silty Fine Sand near Dhaka City of Bangladesh for proposed 750 MW Cyclic Power Plant. Hence about 24 no. of (Borehole) Boring and Drilling up to depth of 55 m from existing ground level has been carried out. Additionally, 09 nos. of Static Cone Penetration Test (SCPT), 02 Nos. of Dynamic Cone Penetration Test (DCPT), 02 Nos. of Pressure meter test (PMT), 02 nos. of Cyclic Plate load test (CPLT) of suitable capacity with 06 nos. of Seismic Cross Hole Test (SCHT) in boreholes had been carried out. The purpose of PMT and SCHT was to have clear idea about the Seismic behavior - knowhow of site. According to Basic principles of Soil Mechanics and foundation design, it is proved that PMT & SCHT are dynamic test. These tests stimulate field condition of occurrences of earthquake. In later stages of analysis, it is found that site have high probability of liquefaction through use of Geologismiki – Liquefaction Analysis Software. Author of these research paper also felt earthquake vibrations – strong aftershocks during site study where Epicenter of the earthquake was in Myanmar during month of august 2016."

Jan 1, 2017

Standard petrographic profiles for many Permian seams from New South Wales and Queensland have been drawn up. The standard profiles of seams of the same age and from one or more coalfields were used to compile an idealized or type seam sequence for those coals in which more than half the seam profiles were similar to one another. A marked similarity existed between at least 7 of the 10 type seam sequences formed.The configurations of the vitrite-plus-clarite contents of the plies of 95 per cent of the seams could be formed from different arrangements of 3 basic sequences. These were...

Jan 1, 1970

By C. A. Geffen-Fowler

This report, sponsored by the Bureau of Mines, presents the results of an examination of the safety of the Blind Shaft Borer (BSB) shaft sinking system and an alternative modified BSB design concept in comparison to conventional shaft sinking technology. Detailed study of the two systems was also performed to identify and recommend design changes for optimum safety conditions. A comparison of the BSB systems with conventional shaft sinking was made on the basis of relative risk levels. Risk incorporates both the frequency and the potential consequence of accidents. A safety evaluation of the component operations of the two BSB systems was performed using a Failure Modes and Effects Analysis (FMEA) methodology. The results of this analysis show generally that both BSS systems are safer than conventional shaft sinking. The potential risk of conventional shaft sinking operations could be reduced by over 30%, on the average, with the use of the original BSB system, and by an average of about 10% with the modified BSB. Design change recommendations to further improve the safety of these systems include a better fire suppression system, improved man haulage systems and more compact hydraulics. An operational safety manual was also developed for the modified BSB system.

Jan 1, 1981