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By Steinar L. Ellefmo, Fredrik Søreide

"The Norwegian University of Science and Technology (NTNU) and Nordic Ocean Resources AS, with support from Statoil ASA have carried out a project reviewing the knowledge about seabed mineral resources in Norway to identify and prioritize needs for further research and development.A special focus area in the project has been to increase the knowledge of possible massive sulfide mineralizations along the Mid-Atlantic Ridge. This Ridge is a subsea mountain range which separates the Eurasian and the North American continental plates. In this area, seafloor massive sulphides (SMS) are formed from the volcanic and hydrothermal activities along the Ridge. A large part of the North-Atlantic Mid-Atlantic Ridge between Jan Mayen and Spitsbergen is located on the Norwegian shelf.Analysis and interpretations of multibeam data have been carried out by NTNU in cooperation with the Russian Institute for Geology and Mineral Resources of the Oceans in order to disclose relevant areas for the formation of SMS deposits. This analysis has identified several promising areas."

Sep 1, 2014

By David Mast, Amanda Foote, Mina Shinouda

The Michigan DOT’s I‑75 Modernization Project, Segment 3, is a 30-year, $1.2 Billion design-build-finance-maintain project in Southeast Michigan. The scope includes building a nearly 4-mile long, 14.5-foot ID stormwater storage tunnel. The tunnel and pump station are being built concurrent with new roads and bridges, requiring multiple levels of design and construction coordination. Underground risks include the poten‑ tial for encountering granular soils, groundwater, and explosive gases. The new tunnel will be mined by a new open-face TBM and lined with a one-pass steel-fiber-reinforced precast concrete segmental lining. Shaft construction began in early 2020 and tunnel mining in July 2020.

Jun 13, 2021

The Golden Cross mine commenced production in December 1991. Both open pit and underground mines produce 1000 tonnes of ore per day. Mining techniques are discussed along with results and variations to proposed methods of extracting the ore.

Jan 1, 1992

By Christopher Mark

A new method for the design of longwall pillars, called "Analysis of Longwall Pillar Stability" (ALPS), is described. The method is the final result of a research program that included two major field studies, extensive reanalysis of data from other in situ measurements, and detailed evaluations of available pillar design methods. The key problem addressed by ALPS is estimation of the abutment loads applied to longwall pillars. Based on underground stress measurements made in mines in three states, equations for predicting the magnitude, distribution, and time-of-arrival of abutment loads are proposed. Stress measurements are also used to evaluate empirical pillar strength formulas for use in longwall pillar design. ALPS has been verified by application to case histories from several mining areas, and examples taken from the Pittsburgh and the Blue Creek seams are presented. Step-by-step guidelines for using this design method are also given.

Jan 1, 1987

By Christopher Mark

Perhaps the most significant development in coal mine ground control during the last century was the introduction of roof bolting during the late 1940’s and 1950’s. From an engineering standpoint, roof bolts are inherently more effective than the wood timbers they replaced. Roof bolts promised to dramatically reduce the number of roof fall accidents, which then claimed hundreds of lives each year, and they were initially hailed as “one of the great social advances of our time.” Roof bolting also emerged at a time of rapid technologic transformation of the coal industry, and greatly accelerated the transition to trackless, rubber-tired face haulage. The U.S. Bureau of Mines quickly became the new roof support’s strongest advocate. Some state agencies and miners were skeptical at first, but nearly everyone was soon won over. Case histories were reported showing that roof falls could be largely eliminated while productivity increased dramatically. Little wonder that, in the words of one contemporary observer, “roof bolting has been adopted more rapidly than any other new technology in the history of coal mine mechanization.” Yet by the end of the 1950’s, it was clear that roof fall fatality incidence rates had actually increased. It would be another decade before the superior ground support provided by roof bolts would clearly save lives. The story of how roof bolting was implemented by the mining industry, but took so long to live up to its promise, is a fascinating example of the interaction between economics, technology, regulation, and science. It still has important lessons for today.

By Albert L. Toenges

(1) The Castleman Basin was investigated by diamond drilling, engineering examination, and geologic study. Agreements permitting investigation of about 14,700 acres of land were entered into with 79 landowners. Eleven beds of coal between the horizons of the Harlem and Mercer beds were penetrated in drilling. These beds from top downward are: Harlem, Upper Bakerstown, Lower Bakerstown, Brush Creek, Upper Freeport Rider, Upper Freeport, Upper Kittanning, Middle Kittanning, Lower Kittanning, Mount Savage, and Mercer. The total estimated reserves of coal (measured, indicated, and inferred), 14 inches or more thick, in six beds follow: [Coal bed: Etimated reserves, tons Harlem _______________________ 23,430,000 Lower Bakerstown _______________ 44, 688, 000 Brush Creek ____________________ 23, 694, 000 Upper Freeport __________________57, 731, 000 Upper Kittanning ________________ 40, 450, 000 Middle Kittanning ______________42,276,000 Total________________________ 232,269,000]

Jan 1, 1952

By Steve Kral

For the past several years, copper producers have faced a tough business climate. Nagging low prices forced many them to reduce their production and make other drastic cutbacks just to breakeven. And sometimes even that did not work. But, like other downturns in the industry, this latest dismal copper market allowed technology to make further inroads into mining and processing operations. Now that the copper market appears to be making a turn for the better, those years spent investing in technology by equipment manufacturers and forward-thinking mining companies should begin paying off.

Jan 1, 2004

Determination of Flotation Kinetics of Coal Grain Types in a Pilot Scale Jameson Cell using Coal Grain Analysis Method

Sep 13, 2010

By Alan D. Fisher

Amtrak made a decision to replace an aging bascule bridge with a vertical lift bridge for their crossing of the Thames River in New London, Connecticut. The new lift bridge occupies the same alignment and shares the same foundations as the bascule span. During construction the deep foundation caisson supporting the bascule span settled and tilted. Investigation into possible reasons revealed interesting historical facts, both of the construction of the innovative open well caisson foundations and of the state-of-the-art in tremie concrete placing methods in use at the turn of the century. This paper describes both of these topics.

Jan 1, 2008

By C. J. Bise, D. A. Poukhovski

Two integral components of the 30 CFR 48 training requirements mandated for new miners, newly employed experienced miners, and the annual refresher training of all miners are hazard recognition and prevention of accidents. In these categories, instruction shall include the recognition and avoidance of hazards present in the mine, and a review of accidents and their causes. Unlike instruction preparation for fact-based material, program development for hazard recognition places a particular challenge before safety-training specialists because they are often limited in their ability to adequately gauge the trainees' levels awareness prior to training. Further, they must also assure that the training is relevant, and it is presented in a thought-provoking manner. Computer-based instruction is particularly well suited for assisting trainers in developing hazard- recognition topics because it can be used in pre-training and post-training modes for assessment of training effectiveness, in addition to use as a presentation tool. Therefore, this paper will present a recent approach developed at Penn State to apply this technology for assessment and instruction of accident prevention through hazard recognition, with an application prepared for surface coal mines.

Feb 24, 1997

By P. G. Guest

MANY of the gases and vapors used in anesthesia form explosive mixtures with oxygen or air. Sources of ignition for these mixtures always have existed in operating and anesthetizing areas. When ether was first introduced, candles,5 gaslights, and coal stoves caused fires and mild explosions of the vapor-air mixtures. Today the chief causes of ignition are electrical. Fires and explosions are still much too frequent; and, because many of the mixtures are rich in oxygen, the explosions sometimes are very violent. Obvious sources of ignition, such as electric-power sparks and arcs in open motors, switches, and receptacles, as well as exposed incandescent wires and hot plates, usually are recognized by hospital personnel and corrected. A source of ignition that is not so obvious to many is static electricity. Until quite recently the presence of this hazard in a large majority of anesthetizing areas was not even suspected. However, numerous explosions-many of them fatal to patients-have been attributed, with good reason, to sparks from static electricity.

Jan 1, 1953

Effect of Matching Relationship Between Bubble Size and Particle Size on Kaolinite Flotation

Sep 13, 2010

By William F. Hahn

The Bureau Of Mines recognized the desireability of illuminating working places in trona mines. This report describes two illumination system designs, their demonstration and evaluation on a Jeffrey 120HR continuous mining machine in an active working trona mine in Wyoming.

Jan 1, 1980

By D. S. Choi

This paper describes an improved source location technique for microseismic events related to coal mining. A system of non- linear distance equations is solved with the use of the Newton-Raphson method. This computational method is- advantageous when the number of geophones is limited. In addition, this paper includes the results of the analysis of data from several instruments which characterize both mine seismicity and environmental noise such as vehicle traffic. Analysis of the mine seismicity has contributed to a better understanding of caving above a longwall gob and of what constitutes stable ground conditions.

Jan 1, 1990

By Tian Sugui

By means of the measurement of the enduring property and microstructure observation, an investigation has been made into the influences of the element Re and TCP phase on the enduring property of the single crystal nickel base superalloys. Results show that the needle-like TCP phase is precipitated along the <110> orientation on {111} planes in Re-containing/free superalloys during the long term aging, the TCP phase is identified as µ phase, and the precipitated µ phase in 4.5%Re alloy is gradually spheroidized during aging. Thereinto, the needle-like µ phase may obviously decrease the enduring lifetimes of the alloys due to the consumption of the refractory elements and the effect of the stress concentration. But the stress concentration is not easily generated in the regions near the spherical-like µ phase, which is a main reason of reducing the enduring lifetime of 4.5%Re alloy to a small extent.

Jan 1, 2010

By Günter Huber, Bruno Mattle, Helmut Westermayr, Daniel Spöndlin, Max John, Nejad Ayaydin

PROJECT DESCRIPTION Alignment The Strenger Tunnel forms part of the S16 four-lane expressway between Landeckand Bludenz. The construction of this important East-West connection started in 1973with the Arlberg Road Tunnel as its key constituent. Beginning in 1992, solutions for the section between Pians and Flirsch were investigated. Efforts to conserve nature and to avoid potential avalanche and landslide areas led to a solution detouring the villages in the Stanz valley. The starting points were predetermind by the intersections at Pians in the East and at Flirsch in the West. As a result of the expected traffic load and the comparatively high gradient of 2.9%, both one-way, two-lane tubes were constructed at once. The north tube is 5.851 m long, the south tube 5.775 m, see Figure 1. Layout of Tunnel Cross-Section The tunnel cross-section was determined by 2 × 3.75 m wide, 4.70 m high roadways, two sidewalks and sufficient space for two fans above the clearance

Jan 1, 2005

By N. T. Lowe

The National Institute for Occupational Safety and Health (NIOSH), Spokane Research Laboratory (SRL), investigated a means to evaluate the potential impact of surface conditions above underground mines on emergency response activities. Recent events have highlighted the need to conduct critical emergency operations on the surface above underground work areas. Accessibility and usability of the surface, such as the ability to drill holes or deploy seismic monitoring or through the earth communications systems, are an important consideration for emergency response planning. This paper identifies critical surface conditions such as: surface waters, valley fill, highways, railroads and significant structures that must be considered in emergency response planning and in the conduct of emergency operations as they relate specifically to the seismic detection of trapped underground miners. Results of case studies indicate a need to consider the impact surface conditions may have on emergency response capabilities.

Jan 1, 2009

The early development patterns of both Australia and New Zealand were substantially in parallel and both were heavily indebted to gold mining for, providing the stimulus to growth. However, since the mining boom, of 1895 - 1899, the mining sector in New Zealand has progressively declined, while in Australia it has assumed an increasing importance in the economy. The continued dominance of minerals in Australian trade, and the fact that eight out of the top ten companies in Australia are directly involved in mineral exploration and production, has strongly influenced government and public attitude&apos;s to the minerals sector. Although the legal framework of mining and exploration Acts and Regulations are similar it is in, the method of administration, particularly in regard to exploration and prospecting licences, that the gulf across, the Tasman is apparent. Despite the relative ease of application and granting of licences in Australia, in the more settled south eastern part of the continent we are finding more and more land is being zoned unavailable for exploration. In the remote areas, the Aboriginals now control nearly ten per cent of the land area of Australia, virtually with drawing that portion from exploration. The concept of &apos;Australianisation&apos; has softened a hardening attitude against foreign investment in mining on the part of the bureaucracy. This anti-mining attitude is fortunately, not shared by the public, and we can but hope that the will of the Australian people can filter through to our masters in Canberra, and ease the rapid increase in the number of regulatory bodies which does so much to inhibit the normal conduct of business. The delays caused by interminable hearings and committee investigations all cost money. This cost can only rebound back on the end consumer, who after all is a voter.

Jan 1, 1982

By Kung-Lee Wang

SUSTAINED growth characterized the U.S. economy in 1964. Many new peaks were achieved in production, sales, employment, employee earnings, and business profits. At the end of 1964, the economy had experienced 4 years of uninterrupted expansion, and the greatest net gains in output for all postwar cyclical advances had been registered. There were no indications of the various weaknesses which have previously characterized advanced stages of business expansion. Both gross national product (GNP) and national income were 6.7 percent higher than in 1963. In 1964 GNP totaled $628.7 billion, a gain of $39.2 billion over the 1963 figure. On an overall basis, prices rose 1.75 percent in 1964. The real volume of output of goods and services (GNP in constant dollars) increased by 5.0 percent ill 1964; this was more than the 3.8-percent gain in 1963 but less than the 6.6 percent gain in 1962. The 1964 output gain also exceeded the average 3.7 percent annual increase for the postwar period. Congress authorized a two-stage tax reduction designed to further stimulate economic growth and employment. The tax cut favorably affected the 1964 economy in the following ways: By helping to boost personal income, corporate profits, and industrial production; by accelerating the pace of consumer spending and business capital expansion; and by increasing employment, thereby reducing unemployment to 5 percent. Three major problems remained unsolved. These were unemployment of 3.7 million persons, poverty conditions among more

Jan 1, 1965

By L. C. Bird, N. T. L. Landgren, M. W. Mikhail

"Through funds made available in 1972 by the Nova Scotia Department of Mines and Energy (DME) and the federal Department of Regional Economic Expansion, a program was initiated to recover saleable coal from mine waste dumps adjacent to the existing Acadia wash plant in Stellarton, Nova Scotia.Following evaluation of these dumps in 1972, the Acadia wash plant was modified to treat high-ash material. The first production was recorded in late 1974. By the end of 1979, a total of 738,202 t of dump material had been processed, yielding a total of 205,212 t of thermal-quality coal.The successful Stellarton operation led to considering the possibility of recovering thermal coal from other dumps. Evaluation of the Westville dumps indicated total recoverable reserves of 1,346,617 t averaging 53.8OJo ash.Parameters for plant design were defined from the washability characteristics of the dump material and the results of a bulk test. Two options were proposed; one was to use the existing plant with some modifications, the other was to build a modular mobile plant that could be used at future dump sites in the province after Westville. At the 25% ash level, the potential recovery of coal from the dump was estimated at 41% yield (by weight) or 549,679 t."

Jan 1, 1981