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By Marcelo Claure

"La evolución de los Andes Bolivianos ha estado dominada por arcos magmáticos donde existe una progresiva migración hacia el oeste y que están relacionados a procesos de subducción. El arco volcánico moderno se inicióhacia los 26 Ma debido a la subducción de la placa de Farallón y subsecuente aumento en la velocidad de convergencia. Asimismo, la región de la Cordillera Occidental desarrolló campañas de exploración que condujeron al descubrimiento de numerosas zonas mineralizadas y prospectos de interés económico, debido a las favorables condiciones geológicas para el descubrimiento de diferentes tipos de yacimientos ya sean diseminados, en stockworks o filonianos, con mineralización de plata, oro, plomo, cadmio, indio y germanio, entre otros. En este sentido, el presente texto señala los resultados de esta exploración, los ciclos evolutivos, su cronología absoluta, los rasgos geoquímicos y potencial minero de la región andina. "

Apr 24, 2001

By Rafael Flores

En los últimos años, el Perú ha crecido en términos de energía generada a través de los proyectos mineros y demanda vegetativa, donde se ha verificado un fuerte crecimiento en la zona norte y sur del país. En este sentido, el presente texto desarrolla un análisis del abastecimiento de la demanda del SEIN (Sistema Eléctrico Interconectado Nacional) en su conjunto, así como en los subsistemas centro, norte y sur, a través de la evaluación del crecimiento de la demanda y los nuevos proyectos de generación, considerando principios esenciales en la estructura de un funcionamiento adecuado de los sistemas interconectados.

Sep 14, 2009

By Wellington Pereira Inácio, Fernando Wypych, Sergio Neves Monteiro, Artur Camposo Pereira, Rafael Marangoni

"The efficiency by which an applied load is transmitted from the matrix to reinforcing fibers in a composite depends on the fiber/matrix adhesion strength. This is determined as the interfacial shear strength, IFSS, which may be measured by means of pullout tests that measure the force needed to pull a single fiber out of a block of material simulating the composite matrix. Different techniques are used to perform pullout tests. The objective of this work was to characterize the IFSS of sisal fibers embedded in epoxy matrix through the determination of the critical length pullout curves. As the main results, a relatively small critical length was found for the sisal fiber/epoxy pullout specimens, corresponding to a weaker IFSS. This was compared to other results applying different pullout techniques. Scanning electron microscopy observation identified the mechanism responsible for the weak sisal fiber adhesion to the epoxy matrix.IntroductionSynthetic fiber reinforced composites is today one of the most successful class of materials with increasing industrial applications from house appliances to large airplanes like the modem Airbus 380. However, environmental issues are revealing serious drawbacks related to the fabrication, use and post-use discard of these composites. For instance, the thermoset polymer composite reinforced with E-glass fiber, known as ""fiberglass"" has an energy-intensive fabrication associated with a surplus emission of C02, which is responsible for global warming [1]. Moreover, the glass fiber is considered toxic and also causes long term pollution after being discarded."

Jan 1, 2011

By Fernando Zevallos

Las metodologías actuales para el procesamiento topográfico en las minas subterráneas peruanas pueden ser mejoradas. En el mercado se encuentran módulos de topografía subterránea dentro del entorno de los softwares especializados de minería que integran y automatizan el procesamiento topográfico, la generación de reportes y el manejo de la información topográfica. Este proceso integrado asegura resultados correctos en cuanto a los entregables (sólidos con volumen, planos y reportes). Asimismo, permite reducir el tiempo de procesamiento, que puede ser usado para elevar el nivel de detalle del levantamiento topográfico y realizar una correcta gestión de la información topográfica.

Sep 20, 2019

By Alejandra Díaz

La minería es una actividad importante para las regiones de Moquegua y Tacna. Sin embargo, el desconocimiento de su importancia económica -en tanto producción de rocas y minerales industriales tales como la sílice, calcáreos, arcilla común y rocas ornamentales, cuyas ocurrencias y canteras verificadas en estas regiones corresponden el 63% a minerales industriales, 20% a los áridos para la construcción y 16% a las rocas ornamentales- conlleva promover el conocimiento y uso de los minerales industriales. En ese sentido, el presente texto señala el potencial geo-económico de las rocas y minerales industriales que existe y explota en estas regiones y así estimular su inversión en actividades mineras e industriales, relacionadas con el aprovechamiento de los recursos de rocas y minerales industriales (RMI), orientándose a disminuir las importaciones y aumentar las exportaciones capaces de generar divisas.

Sep 14, 2009

By M. Matthias

A study, part of a doctoral dissertation (Matthias, 1991), was conducted during 1987 and 1988 to establish the means by which professionals assess and maintain their competence during the various stages of their careers. The study elicited responses from fifty-nine subjects representing engineering, pharmacy and medicine (twenty subjects from engineering, nineteen from pharmacy and twenty from medicine) on their perception and assessment of continuing competence. The findings revealed a wide variation of how professionals perceived their continuing competence and the means they adopted to keep current. The implications of the study are significant for adult education practice and theory building. The author strongly believes that now, more than ever, engineers must take ownership of their careers and professional development activities. While management and supervision have a key role to play, it is the engineer, who is ultimately responsible for the scope, planning and implementation of her/ his professional development needs. An example from one high technology company will illustrate these points.

Jan 1, 1999

By Philip S. Mathews

THE tremendous stimulus given to the mining industry by the gold and silver policy of the present administration has found the capital market for mines ill prepared to afford practical means of financing. Particularly has this been true of the host of abandoned high-cost producers and prospects which increased gold and silver prices have made potentially profitable. In a comparatively short time, experience has demonstrated abundantly that valuable properties have frequently failed to secure capital, while questionable properties have drawn to themselves and their promoters more of the public moneys than their prospects justify. Singularly enough the fault is usually attributable to faulty financing. Discussion and study of this problem are vital to the industry.

Jan 1, 1936

By Ronald Ticona

Con el objetivo de mejorar la trazabilidad del mineral desde mina a planta en una operación de una mina de cobre del Perú, se evaluó el impacto en la planta de procesamiento en relación con las optimizaciones de voladura, un sistema de trazadores, relacionando el desempeño de los procesos de mina a planta con las propiedades geotécnicas y geometalúrgicas, detectando en tiempo real minerales en la planta de procesos alimentación estéril, alta, baja Ley, mineral con Arsénico, entre otros.

Sep 29, 2023

By R. S. Douglas

Introduction The mine at Copper Mountain of the Granby Consolidated Mining, Smelting and Power Company was one of the pioneers in the use of blast-hole diamond drilling for ore breakage. This method of mining has now been brought to a high degree of perfection. The system in use has?been described in a previously published paper which has become an important part of the literature o the blast-hole drilling method. At the time of the establishment of the system at Copper Mountain, standardized loading and drilling procedures were set up. These procedures were based partly on the results of experiment and partly upon the judgment of men experienced in breaking rock in the mine. The success of the method has been proof of their adequacy. With the progress of scoping in the mine, the diamond drill method of breaking was applied to other ore blocks where different conditions obtained. It was found necessary to make adjustments in the standard procedures to get the best results under the new conditions. The following paper attempts to express, in terms of mathematics, the relations of the variable factors. Until recently, estimations of drilling required were based upon the tonnage to be broken and the proposed rate of explosive loading. A revised method of estimating is outlined below which is direct and which involves no unrelated variable factors.

Jan 1, 1947

By Brian D. Smith, Batric Pesic

Typical sulfide gold bearing ores are refractory to standard cyanidation practice. This type of ore always needs some form of oxidative pretreatment to destroy the original host mineral matrix to make the cyanidation possible. The oxidative pretreatment can be achieved by roasting, autoclave leaching, bioleaching, or some other chemical method. Today, the most common practice of ore oxidation is either roasting or pressure leaching. The other methods are still considered developmental.

Jan 1, 1992

The American Mining Congress, 841 Munsey bldg., Washington, D. C. J. F. Callbreath, Secretary. The American Mining Congress is a trade association rather than a technical society and as such does not issue scientific papers. Aside from the articles appearing in the monthly Mining Congress Journal, and the Proceedings of the Annual Meetings, only two works have been issued. They are: The standard handbook on mining methods, practice and equipment. $3.

Jan 1, 1933

The figures given here were received through the courtesy of the Bataafsche Petroleum Maatschappij and the Standard-Vacuum. There is an increase in production for the year of approximately 4½ million barrels. In November the average production indicated that during the year 1935 the total production would probably exceed 50 rnillion barrels. To maintain this production, only 106 wells were drilled during the year, mainly in South Sumatra.

Jan 1, 1935

As the awareness and concerns on subsidence issues increase, there are clear, challenging and credible community expectations for responsible mining, public safety, optimal resource recovery and effective land use and environmental management, coinciding with a changing and strengthening regulatory environment being implemented by the NSW Government. This paper discusses a number of areas where cultural changes in the mining industry will assist with improved subsidence management to meet the enhanced standard.

Jan 1, 2003

There has been much debate in the past as to whether the Australasian Institute of Mining and Meteorology ("AusIMM") should issue valuation guidelines in addition to the ASX and NCSC requirements. My experience in preparing independent expert reports has been that "best practice" sets higher standards than any laws or requirements set out by the ASX and NCSC. This is where I see the AusIMM coming in.

Jan 1, 1989

By Burton E, Eaton R

The incentive to improve wear resistant materials performance is examined with respect to plant availability and recent trends in the labour force. Standard practice at Isa Mine Concentrat- ors in countering the effects of abrasive and corrosive wear is discussed with emphasis on results with more exotic materials such as ceramics and the Cr-Ni-Mo white irons. The paper updates work on rod and ball mill Linings.

Jan 1, 1978

By J. E. Taylor

A detailed planning and design project has been undertaken at Callide Coalfields, as the first step towards implementing a fully integrated mine graphics system. The system, when fully installed, will support applications ranging from business graphics through to terrain modelling and computer-aided design. The conceptual design which will accomplish this is presented. The problems of retrospectively applying graphics standards to existing applications are discussed, and a practical solution outlined.

Jan 1, 1986

By C. D. Jardine, D. G. Patton

Rapidly increasing energy costs and more rigid customer quality requirements necessitate improved control of pelletizing processes. With the introduction of dedicated microprocessor-based controllers, sophisticated control strategies are now possible. An application of this technology at Carol Project has resulted in fuel savings, improved pellet quality, and standardization of operating procedures. This was accomplished with no production loss by using a "building block" approach to design and equipment selection.

Jan 1, 1985

By W. E. Curran

For years the geographical isolation of the Southern iron-ore district from the great producing centers in the North and East enabled it to meet its conditions and solve its own problems without regard to the practices and policies of other districts, but during the past few years distances have been shortened, practices and wages are being standardized, .and these changing conditions have brought new problems to the South.

Jan 1, 1937

By J. N. Economopoulos

The mining industry is becoming increasingly aware of environmental issues and has made big forward steps in the field of environmental management. Legislation, social pressure and competition introduced changes in the industry?s policies and practices in order to conform to the new standards of environmental performance. The paper addresses the need for an integrated and systematic approach to the issues of environmental management within the mining industry.

Jan 1, 2002

By Rogers M, Sullivan B

Golden Crown Mine is a narrow vein gold mine producing 75000 tpa. Production has been predominantly by shrink stoping using hand held machine and airleg. Bogging from these stopes is done with Toro 150 LHD units.Previously the standard development method consisted of developing a sill drive, a footwall drive and millholes every 7 m. This meant that for every metre of ore development, 2 m of waste development was required.

Jan 1, 1993