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By James T. Bartis

Review of Key Issues Affecting the Prospects of CTL in the United States ?Issues of concern to the public - Impacts of coal mining - Water use - Greenhouse gas emissions ?Issues of concern to investors - CTL production costs - Oil prices - How greenhouse gas emissions will be managed ?RAND recommendations

Jan 1, 2009

Workers in underground stone mines have a high fatality rate caused by falls of ground from the mine roof or rib. NIOSH recommendations to reduce ground fall injuries and deaths address baskets, mechanical scalers, mechanical bolters, drill steel changing, personal protective equipment, and training. Description of Exposure An informal National Institute for Occupational Safety and Health (NIOSH) review in 1998 identified approximately 17 new underground limestone operations in vari¬ous stages of planning; as many as 35 new underground stone mines are expected by 2005. Many of these new underground stone mines will employ new or inexperienced workers with minimal knowledge of the hazardous conditions that exist underground. Workers in underground stone mines have a fatality rate nearly 20 times that of workers in the manufacturing sector. Three quarters of the fatalities in underground stone mines are caused by falls of ground from the mine roof or rib (Figure 1) [Statistical Abstract of the United States 1985-1999; MSHA 1983-1999]. During 1983-1999, nonfatal ground falls resulted in 140 injuries, or 15% of all underground, lost time stone mine injuries. These nonfatal ground fall injuries resulted in more than 13,800 lost workdays (one third of all lost workdays). Ground falls generate more disabling injuries and time away from work than any other type of incident. [ ]

Jan 11, 2003

By J. F. Neill, O&apos

[The Cartersville mining district is in Bartow County, Ga., about 40 miles northwest of Atlanta. Barite, limonite, ocher, amber, hematite, and, manganese oxide ores have been produced from the strict since about 1840. In the search for a possible source of manganese ore, Bureau of Mines engineers made a preliminary study of the district from September 1950 to January 1951. During this study 139 deposits were examined, and many mineral exposures were sampled. Manganese mineralization occurs as fine oxide and concretionary pellets in residual clays, as fine oxides in umberous clay, in brown-iron deposits, and in a limited quantity in mud ponds and Jig-tailing piles. The future supply of ferrograde manganese ore from the district, using current mining and benefication methods, appears limited to the recovery of the hard manganese ores deposits. Rough estimates indicate a reserve of manganese-bearing clays of about 8,000,000 long tons. This type of deposit has been extensively exploited and the larger deposits mined out to depths of from 50 to 200 feet. The remainder of these deposits are low grade, are covered with deep layers of colluvium, or lie below the ground-water table. Any future production from this source will require systematic prospecting, improved concentration, and an increase in the price of concentrate.]

Jan 1, 1954

By Ernest E. Berger

"INTRODUCTIONOne of the outstanding problems in the normetallic industries, and one which involves two of the greatest of these industries, cement and gypsum, is the reaction of Portland cement with calcium sulphate. To all Portland cement clinker there is added in the manufacturing process, a small amount of retarder, as a necessary ingredient of the finished product. This retards the initial set, increases the strength, and adds to the plasticity of the cement so it will have the desired working and setting qualities. The retarder commonly used is gypsum, (CaSOA.2HO), which is the hydrous form calcium sulphate. Calcium sulphate is also available as plaster of Paris (CaSO4 1/2 HC) and anhydrite (CaSO4). The purpose of this inquiry was to determine the form or mixture of forms best adapted for retarder. The problem is complicated by the fact that cement clinker is a complex mixture of calcium silicates and aluminates, and that clinker from different mills, making cement of approximately equal quality, differs considerably in chemical constitution. Thus the same retarder may give very different results with different types of clinker, especially in the percentage of retarder required for the same degree of retardation.It has been known for some time that a small percentage of plaster of Paris will greatly retard the time of set of Portland cement as well as increase its strength and plasticity, but whether gypsum and anhydrite will have a similar effect is as such disputed question. The offects of gypsum have received little consideration in laboratory research because, even though it will not retard a clinker when the two are mixed in the laboratory, as has been noted in some instances, the cement will have a normal set when the two arc mixed in the large tube mill at the plant, so that practically, gypsum seems to be equally as goou as plaster of Paris, and because of the great saving in cost it has been used almost exclusively."

Sep 1, 1925

Since March 28, domestic producer prices on 99.5 percent aluminum ingot have been at 5l¢ per pound. Dealers in this same time frame have held ingot quotes at 49¢-50.5¢ per pound. COBALT: Imports from southern Africa in 1976 constituted 73 percent of total cobalt imports. Moreover, the United States is 98 percent dependent on imports of cobalt. For this reason, the Bureau of Mines is closely monitoring developments abroad to ensure an advance notice of any possibility of a shortfall in supply. Included in these imports were those from Zaire (41 percent directly from Zaire and 15 percent via Belgium-Luxembourg), Zambia (11 percent), and Botswana (6 percent). Also being closely watched are industry stocks.

Jan 1, 1977

By Fred W. Johnson

The first section of this circular has been prepared with a view to answering inquiries frequently received by the Bureau regarding laws governing the staking of claims and regulations covering requirements for holding them and obtaining title in fee to placer ground. These laws and regulations were summarized briefly in Information Circular 6796, "Placer Mining in the Western United States." These laws, however, are administered by the General Land Office, Department of the Interior, and it has been considered advisable to combine an authoritative résumé thereof by the Commissioner of that Bureau with information on small-scale placer mining previously published by the Bureau of Mines. The second section of this circular is largely a revised reprint of Information Circular 6611, "Small-Scale Placer Mining Methods", first published in April 1932 for the purpose of answering the many daily inquiries then being received on this subject. This circular has been reprinted repeatedly, and about 30,000 copies have been distributed, most of them in response to applications therefor. At present (June 1937) requests for this publication continue to be received daily.

Jan 1, 1938

By David Portocarrero, Kevin B. Heather, Stewart D. Redwood, Erika Dávila, Hubert Gamarra

El proyecto Antakori (Regulus Resources Inc.) está ubicado a 53 km al noroeste de la ciudad de Cajamarca en el distrito minero de Hualgayoc y es parte de la cuenca de los depósitos de Cu-Au-Ag del Mioceno del norte del Perú. Tiene un recurso indicado de 250 Mt con 0.48% de Cu, 0.29 g/t de Au y 7.5 g/t de Ag y un recurso inferido de 267 Mt con 0.41% Cu, 0.26 g/t de Au y 7.8 g/t de Ag (Eggleston et al., 2019). La geología consiste en un basamento cretácico de rocas sedimentarias (formaciones Farrat, Inca y Chulec) intruído por varios diques de pórfido que generan alteración y mineralización tipo skarn con mineralización de Cu-Au-Ag y cuerpos de sulfuros masivos. Posteriormente, se desarrolla un sistema tipo pórfido asociado a diques de pórfido cuarzo-feldespato-(biotita) y cuerpos de brechas con mineralización de Cu-Au-Ag-(Mo). Sobre las secuencias sedimentarias se depositan rocas volcánicas del Mioceno procedentes del centro volcánico Tantahuatay y son intruídas por diques/stocks subvolcánicos, ambos afectados por una fuerte alteración argílica avanzada con mineralización epitermal de sulfuración alta de pirita-enargita con Cu-Au-Ag-As-Sb. Un sistema epitermal de sulfuración intermedia con mineralización tipo “Carbonate-Base Metal” de Au-Ag-Pb-Zn-Cu, asociado a diques, de pórfido hornblendico constituye el último evento de mineralización en el proyecto Antakori.

Sep 20, 2019

By Hugo Medina M.

La cuenca de Casma, Chimbote es una de las tres unidades que conforman el EUGEOSINCLINAL de la zona tectónica Chiclayo- Pisco, cuya estratigrafía se divide en Grupo Chimbote, Casma y Volcánico Calipuy, cuyas nuevas formaciones y unidades menores se designan con nombres de la localidad. En este sentido, el texto describe las unidades del umbral de Cuenca, como las rocas instrusivas del "Batolito de la Costa" de amplia distribución. Así también la cuenca posee yacimientos metálicos y no métalicos, siendo de importancia los primeros para el desarrollo siderúrgico. Entre estos tenemos las calizas dolomíticas, carbón, antracita, etc.

Oct 14, 1980

By Frank G. Miller

Controlling natural-water drives to effect efficient and economic production of petroleum, through wells, from reservoir sands and rocks is a problem of major importance in the oil-producing industry. Water-drive fields are characterized by large quantities of mobile water under high pressure immediately below the oil in the flanks or extraneous parts of reservoir formations, Hence, the water, which is in fluid connection with the oil and a source of a large proportion of the energy available for moving it, advances up-structure to replace it. This phenomenon of water moving crestward into the oil-bearing parts of the reservoir and replacing oil is termed edgewater encroachment. The mechanism by which oil is flushed out and continually replaced by water as the hydocarbon content of the field is depleted must be understood if natural-water drives arc to be used successfully to, induce efficient recovery of oil from its reservoir rocks. Until recently, the function of water in the production of oil has been somewhat obscure and was not given the consideration it deserved in early petroleum production-research programs because of the greater importance associated with and the effort devoted to investigations concerning the relations of natural gas to production of oil. Thus, with virtually no fundamental information at hand, it is not surprising that at first edgewater was considered a necessary evil, and the manner in which it was dealt with depended largely on the experience of the operators. During the intervening years, however, practical information on encroachment of edgewater in oil sands has been widely disseminated as a result of studies of oil-field depletion, and many theories pertaining to petroleum-reservoir energy and performance have been advanced; these theories necessarily included consideration of edgewater as an integral -art of the reservoir fluids and a source of energy for propelling hydrocarbon fluids through the reservoir and to the surface of the ground.

Jan 1, 1941

By Frank G. Miller

Controlling natural-water drives to effect efficient and economic production of petroleum, through wells, from reservoir sands and rocks is a problem of major importance in the oil-producing industry. Water-drive fields are characterized by large quantities of mobile water under high pressure immediately below the oil in the flanks or extraneous parts of reservoir formations. Hence, the water, which is in fluid connection with the oil and a source of a large proportion of the energy available for moving it, advances up-structure to replace it. This phenomenon of water moving crestward into the oil-bearing parts of the reservoir and replacing oil is termed edgewater encroachment. The mechanism by which oil is flushed out and continually replaced by water as the hydrocarbon content of the field is depleted must be understood if natural-water drives arc to be used successfully to, induce efficient recovery of oil from its reservoir rocks. Until recently, the function of water in the production of oil has been somewhat obscure and was not given the consideration it deserved in early petroleum production-research programs because of the greater importance associated with and the effort devoted to investigations concerning the relations of natural gas to production of oil. Thus, with virtually no fundamental information at hand, it is not surprising that at first edgewater was considered a necessary evil, and the manner in which it was dealt with depended largely on the experience of the operators. During the intervening years, however, .practical information on encroachment of edgewater in oil sands has been widely disseminated as a result of studies of oil-field depletion, and many theories pertaining to petroleum-reservoir energy and performance have been advanced; these theories necessarily included consideration of edgewater as an integral part of the reservoir fluids and a source of energy for propelling hydrocarbon fluids through the reservoir and to the surface of the ground.

Jan 1, 1941

By Terry J. Close

In 1986 and 1987, at the request of the U.S. Bureau of Land Management, U.S. Bureau of Mines personnel studied 7,040 acres of the 7,240-acre Sheep Mountain Wilderness Study Area (OR-006-003) in order to evaluate its identified mineral resources. The area studied is along the divide between the Snake River and Pine Creek about 1.5 mi south of the village of Oxbow in Baker County, OR. No mineral resources or mineral-related activities were identified in the Sheep Mountain study area. The basalt covering most of the study area has no known mineralized sites. However, it contains common agate and opal that is of limited interest to mineral collectors. This basalt (stone) could be used locally as construction material (crushed stone or fill); however, suitable material is wide spread in the region and more accessible to possible markets.

Jan 1, 1987

By Walter D. Holland

This is one of a series of instruction guides developed to help instructors present health and safety training courses to workers in the coal mining industry. This course is intended for training those, usually the safety officers, who perform surveys fur inhalation contaminants in above ground work areas. The handbook entitled ?Handbook for Surveys of Inhalation Contaminants in Above Ground Coal Mining and Processing Work Areas? (NTIS #PB-243-35";) is used as a manual for the course and as a prime reference when performing the actual surveys or interpreting the sampling results. There are six experiments for the students to perform during the course to familiarize them with the sampling devices routinely used during the surveys.

Jan 1, 1976

By R. L. Virta

Ball Clay -- Four companies - H.C. Spinks Clay Co. Inc. (owned by Lhoist Group), Imerys Group (formerly Kentucky-Tennessee Clay Co.), Old Hickory Clay Co. and Unimin Corp. - mined ball clay in four states during 2010. Production, based on preliminary data, was 910 kt (1.11 million st) with an estimated value of $42.9 million. That was a 10-percent increase in tonnage from 831 kt (916 million st) with a value of $37.7 million that was produced in 2009. Tennessee was the leading producer state with 61 percent of domestic production. It was followed by Texas, Mississippi and Kentucky. About 70 percent of production was airfloat, 20 percent was crude and 10 percent was water-slurried.

Jan 1, 2011

By Wils L. Cooley

Several aspects of coal mine safety-ground system operation are studied. Evaluations of two sophisticated ground-wire monitors are presented, along with a detailed report of development work on a modular ground-wire monitor. A portion of the report covers stray current flow in the safety-ground system, analyzing in detail conditions surrounding the generation of both dc and ac ground wire current. Considerable detail is provided concerning studies of mine ground beds. Additional progress is reported in the development of a. continuous ground-bed monitor, and new techniques are developed for the design of ground beds and their resistance measurement. New methods of accurately measuring electrical parameters of finite layered conducting structures are also reported. The effects of stray currents in ground beds is included. Touch-and step-potentials associated with mining equipment are analyzed, and methods are presented for determining earth voltage gradients around structures contacting earth. Instrumentation to determine gradients easily is suggested. Finally, an extensive effort is described dealing with lightning transients on open-pit coal mine ground systems. The nature of the transients, their expected frequency of occurrence, and the ways in which they damage equipment are analyzed in detail.

Jan 1, 1977

By William L. Crentz

This Investigation of the preparation characteristics of the coals in Armstrong County, Pa., is the third in a series of Bureau publications by counties appraising the practicability of upgrading marginal deposits to metallurgical standards. Earlier investigations covered the washing characteristics of the coals occurring in Cambria County, and the principal reserves remaining in Indiana County. In Armstrong County, the Upper Freeport bed is the major source of production, the Lower Kittanning bed being of secondary importance. The Lower Freeport bed is mined to some degree, but it is usually too thin and spotty in occurrence to support large-scale operations. The remaining production is taken from the Pittsburgh, Middle Kittanning, and Upper Kittanning beds, but the quantities are insignificant. Table 1 shows the county's coal production) by beds, during 1948. The coals of Armstrong County are not generally considered to be of metallurgical quality because of the high sulfur content. The raw coals usually analyze more than 2 percent sulfur, and more than 4 percent sulfur is not uncommon, especially in the Lower Kittanning bed.

Jan 1, 1951

By C. M. Harrer

The location, features, qualities, and extent of iron occurrences and the associated resources--limestone and dolomite, bentonite, coal-lignite, petroleum and natural gas, power, and water--are evaluated. The results of pioneer beneficiation tests on South Dakota taconite are discussed. In addition, pertinent features of taconite development, cost factors, the Western and Central United States trade area and markets are reported. The State's production of iron ores until 1963 has been small and for purposes other than the manufacture of iron. This investigation disclosed the probability of large resources of taconite in Pennington and Lawrence Counties. The average iron content is 29 percent, and a 65-percent or better iron concentrate might be produced. Ample resources are available for mining and processing taconite. An investment of at least $26 million would be required for a plant capable of turning out 1 million tons of agglomerated iron concentrate per year. The feasibility of such an enterprise is indicated, but intensive investigation and research must be completed to justify such an investment,

Jan 1, 1966

By Gailen T. Vandel

El presente texto describe la historia, geología, exploración, actividades de explotación como parte de la construcción de la planta de beneficio en la Bahía de San Nicolás, Marcona. Dicho proyecto contempla una ampliación del la planta de chancado y almacenamiento de la mina, así como la faja transportadora de bajada a San Nicolás y red de carreteras. Asimismo se incluye la planta eléctrica Diessel y transmisión, el muelle y zona abycente, la expansión de esta planta para el tratamiento del chancado, la planta de la peletización y la planta térmica. Con la implementación de estos elementos a la planta de Marcona, se convertirá a la región en uno de los centros industriales de mayor importancia en Sudamérica.

Jul 20, 1961

By O. C. Blade

"INTRODUCTION This report on the properties of motor fuels sold through service stations in the United States is a continuation of a series of reports made in accordance with a cooperative agreement between the Coordinating Fuel Research (CFR) Com¬mittee of the Coordinating Research Council (CFC) 3/ and the Bureau of Mines of the United States Department of the Interior. The first of these reports presented data on motor gasolines sold during the winter of 1935-36. 4/ Further re¬ports were issued describing motor gasolines sold during the succeeding summers and winters to and including the summer of 1941.4/ No reports were made on motor gasolines sold during the winter of l941-42 and during the summer of 1942. However, starting with the winter of 1942-43, the semiannual reports were resumed. The present report presents analytical data for 3,011 samples, representing the products of 113 companies. Most of the samples represented in this report were obtained during July and August 1946. As in previous surveys the companies covered by the survey include both large and small suppliers. Conforming to former reports, the data cover three groups of samples - regular-price, premium-price, and third-grade gasolines.As the number of analyses submitted for samples of third-grade gasoline are not considered adequate to represent this type of motor fuel, data for the analyses have not been averaged, but the individual items are tabulated. The number of samples, items, and brands comprising each group is as follows: Regular-price, 1,585 samples, 311 items, and 99 -brands; premium-price, 1,422 samples, 280 items, and 94 brands; third-grade, 4 samples, 4 items, and 4 brands. The meaning of these terms as used in the survey is as follows:"

Dec 1, 1946

By J. A. Cruise

From 27th to 29th September, The South African Institute of Mining and Metallurgy held a Colloquium on Equipment Alternatives in Underground Mining in Johannesburg. The Colloquium, which was highly successful, was held concurrently with the 1988 Electra Mining Exhibition. Particle characterization The Fourth European Symposium on Particle Characterization is to be held in Nirnberg, West Germany, from 19th to 21st April, 1989.

Jan 1, 1988

By F. S. Boericke

"INTRODUCTION The mineral found in natural-chromite deposits is never pure Fe0.Cr203, but rather one in which the Fe0 and Cr203 are in part replaced by Mg0 and A1203, respectively. The purest gravity concentrates from many domestic de¬posits consist of a mineral referred to as ""picotite,"" in which this isomorphous replacement is such that the ratio of chromium to iron is low. The Bureau of Nines has investigated methods of chemically beneficiating ores that contain too much iron to be classed as ""high-grade"" chromite 3/ Early investigations 4/ demonstrated that high-iron chromite or picotite ores can be roasted with carbon to obtain selective reduction of the contained iron, and that most of this reduced iron can be removed by acid-leaching the roast products to produce residues of higher chromium-to-iron ratios. tests 5/ indicated that commercially acceptable reaction rates cannot be obtained at roasting temperatures below 1,3000 C., using solid carbon as reducing agent. By this high-temperature reduction and subse¬quent acid-leaching, however, all ores investigated, regardless of the original composition, readily yielded residues considerably better than the minimum specifications for high-grade chromite.In an effort to obtain satisfactory reduction of chromite at lower temperatures, liquid and gaseous seducing agents were tested with varying success. Of the several reducing agents used, methane appeared to be the most promising and was shown to be highly effective at temperatures between 1,000º and 1,100º C., roughly 300º below the roasting temperatures necessary in solid carbon reduction. Further experiments indicated that mixtures of methate with some diluent (hydrogen or other nonoxidizing gas) gave better reduction than did methane alone."

Feb 1, 1946