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The headwaters of Skippers Creek and the Shotover River are reputed to be among the richest alluvial gold catchments in the world. This alluvial gold has no doubt been derived from reef systems similar to, and associated with, the Bullendale lodes. Physiographically the prospect covers steep ridges and deeply incised gullies between the Richardson Mountains in the west and the Harris Mountains in the east. Vegetation is mainly tussock with bush either side of Murdochs Creek. Access to the area is by metalled road to Skippers and then by 4WD track to Bullendale. Alternatively the prospect area can be reached by helicopter from Queenstown in around ten minutes.

Jan 1, 1992

By Liming Yuan

Barometric pressure changes affect air density, leading to change in the mass of the gas in the gob. When the barometric pressure decreases, the volume of gas in the gob expands, while the volume of gas contracts when the barometric pressure increases, causing the gob to breathe out and in. Although the concept of gob ?breathing? is simple, its effect on spontaneous heating of coal in the gob area is not clear. In this study, computational fluid dynamics (CFD) simulations were conducted to model the spontaneous heating of coal in longwall gob area under measured barometric pressure changes. A single longwall panel using a bleederless ventilation system was simulated. If there is no barometric pressure change, the intake airflow rate is equal to the return airflow rate. When the barometric pressure changes, these two airflow rates are no longer equal, and the difference between the two airflow rates represents the airflow rate the gob breathes in and out. The effect of inflow and outflow of gas on the potential spontaneous heating in the gob was investigated using the CFD model developed in our previous study. The effect of barometric pressure changes on the spontaneous heating was found to be dependent on the gob permeability and the coal oxidation rate. The effect of barometric pressure changes on oxygen concentrations in the gob was also examined.

Jan 1, 2010

By Erich U. Petersen

Recognition of mineralogical and chemical zoning patterns associated with mineralization is an integral part of mineral exploration. Even though the origin of zoning may not always be known, zoning patterns as expressed by the systematic distribution of ore and gangue minerals, alteration or elemental assays (soil and rock geochemistry) have received much attention and are extremely useful in guiding exploration efforts toward locating economic mineralization. By contrast, the potential of using zoning information recorded in solid-solution minerals to address practical geological-engineering problems has received less attention. Solid-solution minerals can provide critical information for common problems faced in exploration, mine development and valuation. Mineral zoning information from solid-solution minerals can now be easily obtained because advances in electron microprobe instrumentation have made these instruments a most efficient, accurate, economical and practical tool for analysis of large numbers of samples. Now entire mines and districts can be studied in a timely and cost-effective manner as required by modern mineral exploration and mining practice. This article shows how knowledge of the composition of fahlore minerals can be used in addressing important problems in exploration, development and valuation. Situations are described in which drilling intersected "low grade zones" (Case one: Orcopampa, Peru, precious metal system) and where there was a need to determine the "lateral correlation of multiple ore intercepts" (Case two: Sheep Creek, Montana, sediment-hosted sulfide deposit).

Jan 1, 1992

At a regional scale, the Otago Schist has been divided into textural zones, metamorphic zones, structural transposition zones, and terranes and lithologic associations. Each of these subdivisions reveals aspects of the internal structure of the lithologically monotonous Otago Schist but, to date, a map of the schist derived directly from structural data has not been made. In the present study, digitised structural data from the QMAP GIS were used to make a form line map of Schist foliation which, in turn (and using certain non-unique guiding assumptions), was used to construct a provisional foliation thickness map of the Otago Schist. Contours of dominant foliation (Sp) thickness have been drawn from 4 kIn above to 16 km below the reference level of the Caples-Torlesse terrane boundary in the schist structural pile. A recent revision of the Otago Schist textural zone classification has shown that the grain size of metamorphic white micas increases progressively with textural grade. There also appears to be a correlation between schist mica grain size and foliation thickness. Using mica grain size, it may eventually be feasible to establish the vertical structural position of samples in greenschist facies parts of the schist pile to a precision of ¦ 1 km or better, even if they are in inliers or fault-bounded blocks. Foliation thickness and mica grain size are thus potentially useful tools for research and exploration in the Otago Schist in that they assist with structural interpolation and extrapolation. Even at this early stage of application they can be used to provide hitherto unobtainable, semi-quantitative estimates of displacement on Mesozoic and Cenozoic faults and folds.  

Jan 1, 2001

This paper examines the reform of mining legislation over recent years, the establishment of new Crown land management agencies, and the role of the Crown and environmental groups in nature conservation inNew Zealand. It describes the relationship of the minerals industry to the Department of Conservation and environmental groups over recent years, and the prospects for mineral development on the Conservation Estate in future.

Jan 1, 1995

Nominating Committee.-On the recommendation of the President, the Board of Directors, at their meeting on Apr. 25,1913, appointed the following Nominating, Committee to nominate officers and directors for next year: John Hays Hammond (Ex-President), Chairman. Robert H. Richards Chairman of Boston Local Section. Richard S. McCaffery, . . . . Chairman of Spokane Local Section. Chester F. Lee Chairman of Puget Sound Local Section. Frederick G. Cottrell, . . . . San Francisco, Cal. Charles W. Goodale Butte, Mont. James W. Maleolmson, . . . . Kansas City, Mo.

Jan 5, 1913

By P. A. Croce

A total of 17 mine gallery fire tests (23 including sub-tests) were completed during this report period (10/1/76 - 11/30/77), directed at identifying a hazardous timber-set fuel-loading in a mine passageway that is otherwise free of combustibles. Results of these initial tests show that the capability of a particular fuel loading for propagating a fire is dependent upon the imposed ventilation air velocity and the ignition intensity, although this dependency needs to be better defined. It is also apparent that care must be taken when relating gallery test fire behavior to actual mine fire behavior, because of the restrictive length of the gallery. Present data indicate that some modification to the instrumentation scheme may be advantageous before proceeding with future tests.

Jan 1, 1978

By J S-L Chan

"An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation. Cu-Ag-Au mineralisation at Kluwih prospect in Eastern Java, Indonesia is related to a high-sulfidation hydrothermal system within a volcanic dome (2.35 × 1.7 km diameter). The mineralisation occurs mainly in steeply dipping, structurally-controlled quartz-enargite-pyrite veins (several centimetres to 2 m wide) and is hosted mainly in porphyritic dacite, volcaniclastic rocks and volcanic breccia of the dome and in an underlying andesite that yielded a zircon U-Pb age of 11.5 Ma.Short wave infrared spectrometer analyses were carried out for alteration mapping at Kluwih. There are two main stages of alteration produced by the hydrothermal activity. The alteration mineral assemblages indicate an advanced argillic alteration. The Cu mineralisation occurred in the form of enargite and subordinate chalcopyrite with an intergrown texture in the early stage. These mineralised veins are characterised by narrow pyrophyllite ± diaspore and dickite selvages (metres wide) and a peripheral K-muscovite envelope (sericitic alteration) up to 100 m wide. The K-muscovite envelope is zoned outward to Na-muscovite or Na-illite. Late-stage kaolinite and smectite alteration overprints the porphyritic dacite and may obscure the nature of early mica-clay alteration. The spatial distribution of different alteration assemblages suggests that the temperature of hydrothermal fluid increases with depth.Both the high-sulfidation mineralisation and advanced argillic alteration are suggested to be related to magmatic-hydrothermal fluids, which are likely to originate from an undiscovered deeper porphyry Cu-Au system below the porphyritic dacite. Based on alteration mapping results and comparisons to similar deposits, the porphyry intrusion could be up to 500 m below the volcanic dome. Further geochemical and mineralogical studies may help to target the potential underlying porphyry system.CITATION:Chan, J S-L, 2015. High-sulfidation epithermal Cu-Ag-Au deposit, Kluwih, eastern Java, Indonesia – alteration and implications for potential porphyry cu mineralisation, in Proceedings PACRIM 2015 Congress, pp 213–218 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 18, 2015

By R. M. Schuster, F. M. Benavides

Samuel G. Bonasso The article by Benavides and Schuster provides an in-depth study of three transportation alternatives for a four-mine complex in western Kentucky. The examination of aerial tramways was not undertaken as an alternative solution. We feel this is an oversight since industrial ropeways are competitive with both belt conveyance and overland truck hauling. In fact, there are aerial tramway systems, operational today, which are 100 years old and operating with some original components. Maybe unfortunately, there are no fixed rules or guidelines whereby the most cost-effective means of transporting and handling material for a given situation may be selected. Each situation must be evaluated so the variables that influence the selection of the desired alternative can be clearly defined. However, there are in-place industrial ropeway systems that have proven economically feasible over a range of 1.6-50 km (1-31 miles). The more difficult the terrain, the greater the cost efficiency.

Jan 1, 1983

By Loren R. Anderson

A probabilistic slope stability computer model was developed at Utah State University and independently evaluated by CH2M Hill Consulting Engineers as a design and analysis tool. Volume I of this report describes the model and Volumes III and IV are users manuals for the computer programs. This volume (Volume II) constitutes the report by the CH2M Hill. It includes a description of a field investigation and stability analysis of an existing tailings dam. Based on the results of the analysis, the tailings dam was evaluated for redesign using probabilistic considerations. Conclusions are made regarding the usefulness of the model as a design tool.

Jan 1, 1982

By Larry R. Powell

As part of the Bureau of Mines effort to establish a comprehensive subsidence data base for subsidence technology development, subsidence and related data are being compiled for various mining, geological, and environmental situations. This publication presents data for two longwall mining operations in the Northern Appalachian Coal Region. Vertical displacements and relative face positions are tabulated for 104 subsidence monuments. Brief physiographic and geological descriptions of the mining sites are presented along with a general account of the mining and subsidence monitoring methods.

Jan 1, 1981

By C. B. Manula

This report is volume 4 of at. eleven-volume final report for a Grant completed by The Pennsylvania State University for the Bureau of Mines to develop a dynamic general purpose computer simulation model for underground coal mining. The simulator developed under the Grant has a wide range of possible applications in the design and evaluation of underground coal mining systems from the standpoints of health and safety, productivity, and mine environment: The Master Design Simulator consists of nine free-standing function-oriented subsystem models linked together into an integrated, comprehensive model of an entire mining system. The subsystems comprising the Master Design Simulator include geology and reserves, methane generation, roof support, subsidence, production, rail haulage, cost, water generation,' and ventilation. This volume of the final report describes the Roof Support subsystem of the Master Design Simulator. This model is based on popular roof support practices for different geological environments with related restrictions imposed by the Coal Mine Health and Safety Act of 1969. From geological sections, the model determines the anchor horizon for roof bolts and the density of roof support necessary. The roof support subsystem is tied to both the geology and reserves subsystem and the production subsystem of the Master Design Simulator, but can also operate as a free standing model. Several case studies are presented showing the application of the model. A detailed user's manual, including a program listing, is presented in the appendices.

Jan 1, 1974

By D. O. Kennedy

"INTRODUCTION During the recent war attention was directed to prevent the destruction of American industries by sabotage. By Executive order of Lay 19, 1942, the Bureau of Mines was required to conduct investigations and make recommendations that would prevent loss of production of essential war minerals. The Health and Safety Branch of the Bureau of Lines was able to extend its activities with minimum loss of time to include security surveys of the important mineral facilities in the United States.A Mineral Production Security Division was established in the Health and Safety Branch with funds appropriated for that purpose by Congress in April 1942. From July 1942 to July 1945 engineers of this division, under the direction of D. Harrington, Chief, Health and Safety Branch, and J. J. Forbes, Chief, Mineral Production and Security Division, conducted investigations of 1,560 metallic and nonmetallic mines and associated facilities in accordance with the requirements of the Executive order.PURPOSEAn analysis of losses in the production of minerals shows that failure or destruction of equipment either from deliberate or accidental causes produces essentially the same result. Maximum production is insured by the prevention of subversive activities, fires, and industrial accidents."

Sep 1, 1946

By Javier Pozo

La herramienta de gestión corporativa más adecuada en el ámbito de la gran minería es el sistema EAM (Sistema Corporativo de Gestión Mantenimiento de Activos, Enterprise Asset Management). Para que este sistema se realice de manera exitosa, se requiere del compromiso y el apoyo de la gerencia. Posterior a esta etapa de implementación, se desarrolla la de consolidación, donde es importante el apoyo personal externo a la empresa para ejecutar tareas de implantación. Finalmente en SPCC fue necesario un cambio organizacional para la implantanción de MIMS.

Sep 13, 2001

This publication is provided on an "as is" basis without warranties of any kind, either expressed or implied including, but not limited to warranties of title or implied warranties of merchantability of fitness for a particular purpose. The information contained in this publication is for general information purposes only. It does not constitute professional, technical, financial or other advice to the user of this publication and must not be relied upon as such by any person whatsoever. The use of this publication is at the users own risk. The authors/creators of the information contained in this publication have tried to ensure that the information contained herein is correct, but errors or inaccuracies may exist or the information may be incomplete, unreliable or no longer up to date. Therefore, no warranties of any nature whatsoever are given and any liability to any person in respect of anything and in respect of the consequences of anything done or omitted to be done, wholly or partly in reliance upon the whole or any part hereof, are disclaimed, including and without limitation any contractual, dialectal, direct, consequential or financial damages or losses. On no account will Organisers and/or any of the contributors or any person or entity involved in creating, producing or distributing the information and or software available in this publication be liable for any such damages arising out of the use of or inability to use this publication. Copyright Reserved The South African Institute of Mining and Metallurgy P O Box 61127, Marshalltown 2107, South Africa www.saimm.co.za All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical photocopying, recording or otherwise without the written permission of the copyright owner. Although the greatest care has been taken in the compilation of the entire contents, the editors and publishers do not accept responsibility for errors or omissions. First Edition Copyright February 2004 Proceedings ISBN: 0-9584663-5-1 (1 volume and CD-ROM)

Jan 1, 2004

By Wils L. Cooley

The report covers tests and criteria for the establishment of safe grounding systems for coal mines. The work deals primarily with under-ground coal mines, but much is applicable to surface mines as well. Included is an extensive guide to grounding and bonding procedures for mine surface substations. Xit-Rods are evaluated and shown to deviate from manufacturer's claims. An analysis shows that very long cables are difficult to monitor using audio frequency ground-check techniques. A method is developed to detect failing cable splices without removing the cable from service. Simulation and measurement are compared for a technique to detect bad rail bonds, and an assessment is made of grounding techniques for dc face equipment.

Jan 1, 1979

By F. B. Henderson

1.0 PROLOG Since the "end" of the Cold War, revolutionary new research and commercial remote sensing capabilities are being developed that will dramatically change the way we map the earth and address its environmental problems. The technology challenge is not the growth of new environmental remote sensing technologies themselves. It is, rather, how these new innovative observing systems can be accepted and used to the benefit of both the regulatory and the mining communities in the light of present concerns about unknown risks of discovery and liability. The basis for this paper is an unpublished technology primer prepared for the industry-government Workshop on Advanced Measurement and Site Characterization for Mining Impacts held at Colorado School of Mines, Golden, Colorado, July 14-17, 1997

Jan 1, 1999

An understanding of the way that solutes are transported in mining or natural environments is essential to the development of sound strategies for managing waste disposal. Research on miscible pollutant movement in unsaturated porous media is carried out both experimentally and numerically. Results of numerical modelling are obtained by solving the groundwater flow equation and the solute transport equation. The finite element method is employed and comparisons between simulation results and experimental data are found in remarkable agreement.

Jan 1, 1995

Five types of mineral resource were known in the sedimentary cover of the oceans and seas floors prior to the 1980s: 1. hydrocarbon fields including some very large zones of oil and gas accumulation; 2. æRed SeaÆ type thermal oozes with increased concentrations of noble metals; 3. ferromanganese nodules; 4. concentrations of metallic sulphides (æBlack SmokersÆ); and 5. cobalt-bearing ferromanganese crusts on the summits and slopes of seamounts.   Since then, the so called æWhite SmokersÆ, containing sulphides of copper and zinc, have been discovered. The ore horizons (manganese, copper, nickel and other metals) of the sedimentary cover of deep-sea basins comprise a sixth type of mineral resource in the oceans. These horizons have not only a theoretical, but also a principal economic significance.

Jan 1, 1995

By L. D. Johnson

On a project which is to develop a system to suppress coal dust explosions, a facility has been built and several devices tested. The facility is a 317-foot, 4.5-foot diameter shock tube and to date 53 tests have been carried out with methane-air and methane/coal dust-air as the explosive mixtures. Suppression of slowly propagating (up to 300 ft/sec) flame fronts has been successfully carried out on two tests using the dry chemical extinguishing agent Purple K. Delivery of the material directly into the flame front Seems to be required if effective suppression is to be accomplished.

Jan 1, 1972