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The West Coast region of the South Island is situated astride the Pacific û Australian plate boundary zone. The most significant component of this zone is the Alpine Fault. A variety of reconstructions of the pre-Alpine Fault plate tectonic configuration of the New Zealand continental area have been attempted over the past 25 years or so. Most of these have not been closely constrained by a regional compilation of field data related to the age and horizontal displacement history of the Alpine Fault. A model in which the Alpine Fault was initiated no earlier than the interval 18 - 16.5 Ma (B.P.) is proposed, a significantly younger age of inception than has been widely accepted as the onset of dextral displacement along the plate boundary through the South Island. A subsequent history of displacement is presented consistent with the West Coast basin stratigraphy. The alluvial gold content of some parts of the Miocene to Pleistocene conglomerate sequences is also discussed.

Jan 1, 1996

By Lily Ruíz

El presente texto evalúa el relave minero de SIMSA con el objetivo de obtener un producto ecológico que pueda ser utilizado como mejorador cationico de suelos y restaure el equilibrio de los suelos ácidos de la selva peruana. Para ello, se desarrolló un trabajo a nivel de laboratorio, obteniéndose resultados satisfactorios. Posteriormente se pasó al nivel piloto donde a través de la experimentación se utilizó el relave en diferentes concentraciones para la producción agrícola y forestal, reafirmando los resultados en las mejoras de la productividad en suelos ácidos.

Sep 9, 2007

By William L. Rice

This Bureau of Mines Open Pile Report on cobalt is one of a series of minerals availability commodity deposit abstracts. Nonconfidential information from the Minerals Availability Program data base covering domestic and foreign cobalt properties and deposits has been abstracted for use in his report. Abstracts include applicable data on location, published reserves and resources, geology, mine and beneficiation systems, and operation information.

Jan 1, 2011

The Menominee Range of northern Michigan was a major producer of direct shipping iron ore for nearly a century. When the last underground mine on the Range ceased operation in 1978, it marked the end of an era. For since the start of mining in the early 1880's the district has gone through a Lull cycle from the start-up of mining through close-down. During this period over 200 million long tons of iron ore were produced and shipped from nearly 100 mining operations. This development and production spanned the time from when the United States advanced from an essentially rural-agriculatural society through the industrial revolution and into the beginnings of the computer and space age. There are many lessons that can be learned from such a rich history. This report attempts to provide ouch a lesson. Through the use of case histories, deficiencies in past mining practices and mine closure procedures that have resulted in current mine related problems are documented. These problems -an be grouped into three areas; 1) subsidence 2) hydrological or drainage problems and 3) problems related to inadequate mine shaft sealing and capping practices.

Jan 1, 1983

By Fred V. Carrillo

Of the total quantity of secondary copper and zinc that became obsolete in the United States from 19b1 through 1970, more than 11 million tons of copper and 10 million tons of zinc were not recovered. These estimates are based on a study of the flow and recovery of old copper and zinc scrap by consumption end-use. This report describes (1) where copper and zinc are being used; (2) when they become obsolete and available as secondary metal; (3) how they are being collected for recycling; and (4) how much might be recovered from scrap that presently is not being recycled.

Jan 1, 1974

The extraction of minerals and coal at greater depth, employing higher-powered machinery to improve production levels, imposes an increased burden on the ability of a ventilation system to maintain an acceptable mine climate. Hence, mechanical mine cooling systems are often adopted, which can be expensive in terms of both their associated capital and operating costs. Consequently, in order to optimize the total mining costs, it is essential to provide the mine operator with a method with which to determine the most cost effective and efficient mine cooling system. In a previous paper1a novel energy analysis employing the concept of exergy was proposed and applied to cooling systems applied to two conceptual model mines, representative of UK deep coal operations, and their resultant subsurface thermal environ-mental conditions predicted. This paper presents an analysis of the results obtained from the application of this novel technique to assess the performance of various cooling systems applied to a current UK colliery that is experiencing climatic problems due to its depth and highly mechanized production and development workings. To perform this analysis, ventilation and climatic data collected at the case study mine were used to construct balanced mine ventilation and climatic network models to replicate the subsurface environment. Where air conditions exceeded specified climatic limits within identified climatically control zones, mechanical mine cooling systems were employed. A number of cooling system configurations were applied to these model to investigate the potential to satisfactorily regulate the thermal environment. The heat energy transferred out of the air stream by the various cooling methods was absorbed using a variety of chilled water systems, which were designed to operate at various water flow rates and temperatures. Models of various cooling system were developed and applied to control the underground climate within this mine network to within pre-set climatic limits. The results of a comparative analysis of the energy transfers that were produced by the application of the different cooling systems are presented in the form of exergy performance indices. The results produced by simulation models constructed to represent chilled water distribution networks to supply the various air coolers, are designed and balanced. The results of the exergy analyses applied to the operation of the various chilled water pipe networks are discussed and used to assess the exergetic performance of the application of each proposed cooling system to the mine ventilation network.

Jan 1, 2004

By M. E. Alam

In the present study, 1.1 volume percent of nano size copper was incorporated into pure tin using hybrid microwave sintering assisted powder metallurgy route. Microwave sintered samples were extruded both at room temperature and at 230 °C. Microstructural characterization studies were conducted on the extruded samples to investigate the distribution characteristics of secondary phase and grain morphology. Room temperature tensile test results revealed that hot extruded Sn-Cu samples exhibited higher strengths (~ 41%, in case of 0.2% yield strength and ~ 38%, in case of ultimate tensile strength) and ductility (~ 15%) when compared to room temperature extruded samples. On the contrary, the tensile properties of pure tin remained independent of extrusion temperature. An attempt is made in this study to correlate the effect of extrusion temperature on the microstructural evolution and tensile properties of Sn-Cu solder.

Jan 1, 2009

By J. R. Thoenen

In the summer of 1937 the authors began a series of time studies of the various processes employed in' the production of crashed stone. These studies, made at quarries situated in the eastern and southeastern parts of the United States, have not been completed, but to make results available to the industry as early as possible, it was decided to publish summarizes of the studies made to January 1, 1939, as a series of progress reports. The first of these dealt with power-shovel loading and was issued as Report of Investigations 3461 in September 1939. The second, issued in September 1939 as Report of Investigations 3467, dealt with quarry haulage. The present report discusses analyses of time studies of primary drilling a t the same group of quarries. OBJECT OF STUDY Pressure of business problems frequently requires the entire attention of quarry management, and in consequence internal plant economies often are neglected. Also, operating officials absorbed in their local problems are prone to overlook possible economies that would attract attention immediately were they critically examining another plant. The authors felt that technical studies at a number of plants, made by impartial engineers, might disclose opportunities to reduce costs or improve efficiency in internal plant processes.

Jan 1, 1940

The paper discusses the special mixing requirements for Metallurgical Plant Design and outlines the problems associated with the agitation in Mineral Processing Industry today. It also covers new applications such as state of the art large leach tanks and backfill for deep mining.

Jan 1, 2004

The U.S. economy and, consequently, the demand for minerals grew at more moderate rates in 1995 compared with stronger performances the previous year. Demand for metals such as steel and copper was relatively stable. For example, the decline in steel consumed in motor vehicle manufacturing (reflecting lower vehicle sales) for the first half of 1995 was offset by an increase in steel consumed in construction during the same period. More detailed information on events, trends, and issues in the mineral and material sector Is presented below and in the commodity sections that follow. Overall Performance The value of processed materials of mineral origin produced in the United States during 1995 was estimated to be $395 billion, an increase of almost 10% compared with 1994. The estimated value of U.S. raw nonfuel minerals production in 1995 was $38 billion, about 7% more than in 1994. The value of U.S. minerals production has increased in 30 of the last 35 years.

Jan 1, 1996

Apr. 9, AIME, Chicago Section, Chicago Bar Assn., 29 S. La Salle St., Chicago. Apr. 11-12, Geological Society of America, Cordilleran Section, annual meeting, University of Arizona, Tucson. Apr. 15, AIME, Morenci Subsection, Longfellow Inn, Morenci, Ariz. Apr. 15-17, AIME, South West district meeting, Jefferson Hotel, St. Louis, Mo. Apr. 17, AIME, Utah Section, New House Hotel; Salt Lake City. Apr. 21-22, American Zinc Institute, annual meeting, Hotel Statler, St. Louis. , Apr. 21-23, Chemical, Metallurgical, and Mining Society, and Diamond Drilling Research Laboratory, symposium on diamond drilling, Johannesburg, South Africa. Apr. 22, Assn. of Consulting Chemists & Chemical Engineers, Inc., general symposium, Hotel Belmont Plaza, New York. Apr. 25-26, AIME, New England Regional Conference, Kenmore Hotel, Boston. Apr. 26-May 11, Liege International Fair, Liege, Belgium. May 4-8, Electrochemical Society, Inc., Spring meeting, Benjamin Franklin Hotel, Philadelphia.

Jan 1, 1952

By D Fergusson, J D. St George

Highwall stability is a major consideration in optimising opencast mine geometry. It involves assessing the risk of those slope failures that are large enough to have significant cost, safety and/or operational implications. These risks are then balanced against the value of the resource to arrive at an acceptable slope design. Load-deformation models (commonly referred to as ænumericalÆ models) of slopes provide a powerful tool in this decision-making process since they can be verified well before slope failure occurs. This gives the slope designer increased confidence in reviewing designs during excavation, potentially allowing early revision of pit geometry to either increase or decrease safety margins as appropriate. However, these models are not always adopted as they depend heavily on an appropriate choice of constitutive model and material parameters.   A preliminary load-deformation model of a 170m highwall in Solid Energy North (SEN) OperationsÆ Awaroa 4 opencast coal mine in the Rotowaro Coalfield has been prepared. This uses a strain-dependent constitutive model based on laboratory test results, strength parameters developed by SEN and excavation monitoring data. The laboratory testing has included triaxial compression tests on large-diameter fractured samples to characterise the stress-strain response of the closely-jointed soft rock masses that exist in many parts of the mine. Data from the monitoring of a 25m cut made during excavation of a haul road has been used to refine and verify the constitutive model. The resulting highwall model has predicted highwall crest movements corresponding to the excavation of each bench, for comparison with monitored values. Key model outputs are total horizontal movements of about 0.5m near the highwall crest and shear strains of 0.5-0.7% at the locations of potential bedding-parallel shear planes underlying the highwall. Most of the movement is expected to occur as creep rather than as an immediate response to excavation.

Jan 1, 2006

Measurements from an old survey are being machine processed as a pilot project in the development of a computer-assisted method of structural mapping in shield areas. The key element in the system is a field data sheet which requires the geologist to determine a textural hierarchy in each exposure. The pilot system is limited to orientation analysis and utilizes a prior textural analysis, but this would not usually be a problem in utilizing the system ab initio for exploration. A data processing system of this general type offers promise of considerably increased productivity of field geologists by reducing compilation time and improved technical supervision through centralization of processing, and would make structural analysis an economically viable tool in mining exploration and development.

Jan 1, 1969

For the year ending February, 1920 PRESIDENT HORACE V. WINCHELL MINNEAPOLIS, MINN. PAST PRESIDENTS PHILIP N. MOORE ST. Louis, Mo. SIDNEY J. JENNINGS NEW YORK, N. Y. FIRST VICE-PRESIDENT A. R. LEDOUX, NEW YORK, N. Y. TREASURER GEORGE D. BARRON NEW YORK, N. Y SECRETARY BRADLEY STOUGHTON NEW YORK, N. Y

Jan 7, 1919

By Joseph A. Vanous

The inductive communication system was developed under this contract for use in the hoist of deep mines. This program was a four phase program with experimental dual frequency equipment resulting from Phase I, emergency single frequency equipment developed under Phase II, and equipment documentation required under Phase III. An additional emergency system was provided under Phase IV.

Jan 1, 1976

For the year ending February, 1920 PRESIDENT HORACE V. WINCHELL MINNEAPOLIS, MINN. PAST PRESIDENTS PHILIP N. MOORE ST. Louis,. Mo. SIDNEY J. JENNINGS NEW YORK, N. Y. FIRST VICE-PRESIDENT A. R. LEDOUX NEW YORK, N. Y. TREASURER GEORGE D. BARRON NEW YORK, N. Y. SECRETARY BRADLEY STOUGHTON NEW YORK, N. Y.

Jan 9, 1919

For the year ending February, 1920 PRESIDENT HORACE V. WINCHELL MINNEAPOLIS, MINN. PAST PRESIDENTS PHILIP N. MOORE ST. LOUIS, Mo. SIDNEY J. JENNINGS NEW YORK, N. Y. FIRST VICE-PRESIDENT A. R. LEDOUX NEW YORK, N. Y. TREASURER GEORGE D. BARRON. . . . ' NEW YORK, N. Y SECRETARY BRADLEY STOUGHTON NEW YORK, N. Y

Jan 6, 1919

For the year ending February, 1920 PRESIDENT HORACE V. WINCHELL, MINNEAPOLIS, MINN. PAST PRESIDENTS PHILIP N. MOORE ST. Louis, Mo. SIDNEY J. JENNINGS NEW YORK, N. Y. FIRST VICE-PRESIDENT A. R. LEDOUX NEW YORK, N. Y. TREASURER GEORGE D. BARRON NEW YORK, N. Y. SECRETARY BRADLEY STOUGHTON, NEW, YORK, N. Y.

Jan 8, 1919

For the -year ending February, 1920 PRESIDENT HORACE V. WINCHELL MINNEAPOLIS, MINN. PAST PRESIDENTS PHILIP N. MOORE ST. Louis, Mo. SIDNEY J. JENNINGS NEW YORK, N. Y. FIRST VICE-PRESIDENT A. R. LEDOUX NEW YORK, N. Y. TREASURER GEORGE D. BARRON NEW YORK, N. Y. SECRETARY BRADLEY STOUGHTON NEW YORK, N. Y.

Jan 5, 1919

For the year ending February, 1920 PRESIDENT HORACE V. WINCHELL MINNEAPOLIS, MINN PAST PRESIDENTS PHILIP N. MOORE ST. Louis, Mo. SIDNEY J. JENNINGS NEW YORK, N. Y. FIRST VICE-PRESIDENT A. R. LEDOUX NEW YORK, N. Y. TREASURER GEORGE D. BARRON NEW YORK, N. Y. SECRETARY BRADLEY STOUGHTON NEW YORK, N. Y.

Jan 4, 1919