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By S. C. Nordeng

The program described in this paper is primarily a test of the possible utility of multiple regression in ore search, It was carried out as a cooperative project between White Pine Copper Company, the Institute of Mineral Research and the Department of Geological Engineering of the Michigan College of Mining and Technology. The authors wish to thank Dr. Cleaves Byers, Associate Professor of Mathematics, MCM&T, and Mr. Robert DeBaubien, Graduate Student in Mathematics, MCM&T, for their work in programming the project for the computer,

Jan 1, 1964

By D. M. Baird

"THE Island of Newfoundland lies on the extreme eastern edge of the continent of North America and at the extreme northeastern end of the Appalachian geological province. Its belonging to the Appalachian province is shown in the geological history of the region and in the rock types and structures.Geosynclinal sedimentation in early and middle Palaeozoic times was interrupted by Taconic and, more profoundly, by Acadian, mountain building activity. Mid-Palaeo-zoic intrusions range from masses of serpentinized ultrabasic rocks to granite batholiths. A Carboniferous overlay of continental and shallow, drying sea types covers the earlier developed complex. Local basins in these times were filled with products of the erosion of tl1e earlier rocks, and, locally, grew the right kind of vegetation to make thin, discontinuons seams and pockets of coal. Post-early Pennsylvanian history is one of erosion and pene-planation with renewal of movement along many of the older fault systems."

Jan 1, 1960

By Xuexin Ding, Weijie Wei, Jinwang Zhang, Yi Chen, Shengli Yang

"Many ultra-thick coal seams exist in Xinjiang and the northern part of the Inner Mongolia. These coal seams are more than 30-40m thick. This kind of the thick coal seam is too difficult to extract in one slice, so the top-coal caving longwall mining method was designed for this purpose. In order to study the movement characteristics of the overburden strata and the development of the ""three zones"" in ultra-thick coal seams, the physical and numerical simulations were carried out based on the in-site condition of Baiyinhua coal mine. The result shows that, when extracting the upper part of the l 5m thick coal seams, the first weighting interval was 50-58m and the periodic weighting interval was I 8-20m. The caving zone, fractured zone and bending and sinking zone were 38m, 92m, and 50m respectively in height. The fractured zone height increased with the advancing distance of the face, but in some localities, a ladder-like distribution due to the periodic weighting existed. When extracting the lower part of the 25m thick coal seams, the roof was extremely broken and the collapse range of overlying strata continued to increase in irregular form.INTRODUCTIONThe thick coal seams occupy 44 percent of coal reserves in China and account for 45 percent of the gross domestic coal production. There are three main methods for extracting the thick coal seams: sublevel mining, large height mining, and longwall top-coal caving (LTCC) (Wang, 2009). Due to the rapid development of LTCC in the past two decades, it has become the most extensively used mining method. It possesses the advantages of high-production, high-efficiency, low development ratio, and low-cost (Yang, Zhang, Chen, and Zhengyang, 2016; Wang and Zhang, 2015). Baiyinhua coal mine's coal reserves are full of uniformly distributed thick coal seams, with the minable thickness of the main coal seam between 25 to 40m, i.e. the main coal seam is an ultra-thick coal seam. Sublevel longwall top-coal caving (SLTCC) which is an efficient method for extracting the ultrathick coal seams has led to multiple disturbances Xie, Chen, and Wang, 1999; Singh and Singh, 1999; Xie, Chang, and Yang, 2009. Therefore, using the case of Baiyinhua coal mine, the movement features of overburden strata and development characteristics of the three zones in ultra-thick coal seams were studied by physical and numerical simulations (Qian, et al, 2003; Qian, 1994)."

Jan 1, 2016

By Swaminathan Srinivasan, Aaron J. Muck

"When an opportunity arises to combine state-of-the-art concepts with advanced modeling tools, engineers need to take what they know and apply forward thinking to geotechnical solutions to promote the state-ofpractice. Such an opportunity was seized during the design and construction of the Great American Tower in Cincinnati, Ohio. The forty-one story Great American Tower at Queen City Square – currently the tallest building in Cincinnati – has not only changed the downtown skyline, it is also contributing to the advancement of the state-of-the-art use of auger cast-in-place (ACIP) piles as settlement reducers. Predicted settlements of a traditional mat foundation were excessive, and the costs and construction time associated with traditional ACIP piles extending to bedrock were not preferred. A mat supported on a limited number of ACIP piles, with the piles primarily acting as settlement reducers, was evaluated as the preferred foundation type.Promoting the unique soil-structure interaction of the foundation system with confidence required the use of sophisticated numerical modeling tools. Traditional standard penetration test boring data (SPT) was initially used to develop a numerical analysis of the soil-structure interaction using FLAC 3D software. The model was further modified with cone penetration (CPT) and pressuremeter testing (PMT), along with actual load test results on several ACIP pile elements of varying lengths, but all tipping above bedrock. Through a combined design team effort, and detailed numerical modeling analysis, ACIP piles were recommended for reducing mat foundation settlement. Instrumentation during and post-construction confirmed design assumptions and predictions. Integrating sound geotechnical concepts, and using advanced geotechnical analysis and design methods, traditional mat and ACIP pile foundations were successfully integrated into a unique foundation support system.INTRODUCTIONThe Great American Tower at Queen City Square in Cincinnati, Ohio is located within a region dissected by historical geologic deviances associated with the meander of the Ohio River and glacial progression/recession. Combining a challenging geology, with the development of a high-rise office building afforded the design team an opportunity to combine state-of-the-art soil-structure interaction concepts and method with traditional geotechnical engineering concepts. Such a combination required a variety of field tests, collaboration with the design team and owner, and geotechnical-structural modeling during the design phase. During construction, in addition to materials testing and observation, a variety of instrumentation systems were employed. Together, the data was used to corroborate the design model and make adjustments during construction and further substantiate design assumptions following construction."

Jan 1, 2015

By J. P. Hansen

Wustite beds were reduced with carbon monoxide and mixtures of hydrogen and nitrogen in the temperature range 900° to 1,300° C to determine the effect of temperature, gas flow, and surface area on the rate of reduction to iron. The composition of the gas stream as it passed through the wustite bed was continuously measured with infrared absorption cells and heated-wire methods. The change in composition was used to calculate the reaction rates. Arrhenius plots of the data give heats of activation of 34 kcal for particles using CO, 27 kcal for particles using H2, 24 kcal for pellets using C8, and 6 kcal for pellets using H2. The velocity of reduction is dependent on the area of reacting interface and the driving potential of the gas (reducing gas concentration minus equilibrium concentration) as well as the exponential temperature effect. The reaction rate was independent of the gas velocity over the range of conditions studied.

Jan 1, 1965

By AIME AIME

THE PAPER, "Surface Effects on Assay Beads Caused by Metals of the. Platinum Group," presented by J. L. Byers, before the Institute of. Metals Division at the February meeting of the Institute, is the subject of interesting discussion, an abstract of which follows. The original paper is available at Institute headquarters as a Preprint. Member-What assurance have you that the percentage of metals, as stated, is really an accumulation?

Jan 1, 1932

By Edward Hart

The specimen of glazy iron used for analysis was highly characteristic in appearance. It was made at one of the furnaces of the Glendon Iron Works, working a light burden of ore with a highly silicious cinder. There are very few records of analyses of this variety of iron. I have been able to find but the two given by Bell, and I add these to my analysis for comparison. Bell. 1. 2. Iron,......89.47* 88.18 90.70 Carbon, combined,.... 0.00 0.79 0.71 Graphite,......2.88 2.59 2 68 Silicon,......5.47 5 13 5.13 Manganese,.....1.54 0.77 0.56 Sulphur,......0.04 0.17 0.23 Phosphorus,.....0.60 1.12 1.12 Titanium,.....- 0.26 0.18 Calcium,......0.00 0.22 0.20 Magnesium,.....0.00 0.06 0.03 100.00 9929 101.54

By M. Mirnezami, J. A. Finch, M. S. Hashemi A.

The surface of -30µm silica suspension (2% v/v) treated with 100 ppm Mg2+ at pH 11 was fully coated with Mg(OH)2. Under this condition, the silica is strongly positively charged (+30 mV) and the suspension is dispersed. Subsequent addition of Ca2+ promoted aggregation and reduced the surface charge. At this pH calcium is present as Ca2+ and CaOH+, i.e., positively charged ions interacted with the positive surface. Aggregation by a chemical bridging mechanism is proposed. The observation may be relevant to the widespread practice in mineral processing of adding lime to promote aggregation and settling in concentrate thickeners.

Jan 1, 2004

By A Calderon, J Harris, M Shi, D Viswanathan, C Ribeiro Duthie, P A. Kirsch

Mineral resource development activities impact the health and well-being of many people, from workers, to families and surrounding communities. In the current environment of corporate social responsibility life-of-mine planning considers that mining activities should be conducted in the best environmentally, socially and economically acceptable way for the entire life of the mine (ie from exploration to decommissioning and closure). In this context, the health impacts of mining extend throughout the life of the community from worker injury and chronic exposure to communicable and non-communicable causes of illness, through to family and community health and well-being. At the inaugural Life-of-Mine conference in July 2012, the authors proposed the life-of-mine in the life-of-community (LOMLOC) matrix as a framework for understanding issues at the interface between resource extraction operations and the surrounding environment.This paper reviews and compares health activities extracted from social and environmental reports published by selected major mining companies with American operations in Canada, Colombia and Brazil. These corporate approaches to public health management are mapped to the LOMLOC matrix to identify and compare trends and behaviour in corporate health investments. This analysis of how companies approach and prioritise health issues in the context of different regions, cultures and environmental drivers will serve as a resource for minerals industry managers, civil society and regulators regarding current health management approaches in this sector.CITATION:Ribeiro Duthie, C, Calderon, A, Viswanathan, D, ?Shi, M, Harris, J and Kirsch, P A, ?2014. Resource company investments in health – a life-of-mine / life-of-community perspective across America, in Proceedings Life-of-Mine 2014 , pp 349–364 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 16, 2014

By F. Pošepný

Part I.—General Facts and Theories. PAGE 1. Systems of Classification Employed Hitherto, . . 199 2. Standpoint and View of the Present Paper, . . . 206 3. The Xenogenites in General, ...207 4. The Subterranean Water-Oirculation, . . . 212 A. The Vadose Underground Circulation, . . . 213 Filling of Open Spaces Formed by Vadose Circulation, . . 217 B. The Deep Underground Circulation, . 220 Ascending Waters Encountered in Mines, , 222 Related Phenomena near the Surface, . 225 Mineral Springs at the Surface,. . 230 Chemical Constitution of Mineral Waters, . 232 Minute Metallic Admixtures in Mineral Waters, . . . 238 Alterations Produced by Mineral Springs, . 240 Structural Features of the Deposits of Mineral Springs, . . 244 5. Origin of Ore-Deposits in the Deep Region, . . . 247 Manner of Filling of Open Spaces in General, . . . 254 Part II.—Examples or Classes of Deposits. 1. Ore-Deposits in Spaces of Discission, .. 264 General Features and Illustrations, a. Ore-Veins in Stratified Rocks, .. 269 Clausthal, 269; Andreasberg, 270. b. Ore-veins in the Neighborhood of Eruptive Masses, 271 The Erzgebirge, 271; Przibram, 272. c. Ore-Veins Wholly Within Large Eruptive Formations, 274 Hungary, 274; Dacian Gold-field. 275; Verespatak, 276; Vulkoj, 276 ; Comstock lode, 278.

Jan 1, 1894

By Donald L. Katz

FIFTEEN years ago Dr. Manning published a paper in "Petroleum Development and Technology" on '.Fundamental Research Relating to Petroleum." He tabulated for several industries "the proportion of their present success which can be fairly attributed to the application of information and processes obtained by scientific research," giving petroleum a score of 7 compared to 100 for the electrical and coal-tar industries. Today the petroleum industry as a whole and the producing groups both have raised their score beyond the majority and are climbing toward the top. Present practices are being developed both by fundamental research and the application of the research method in field operation.

Jan 1, 1941

The Brothers hydrothermal system is host to two very contrasting vent fields and to date, is the only known example of this kind for any submarine arc volcano in the world. Firstly, there is the NW caldera field. It is perched on the caldera walls and is up to 1,200 years old, and represents a more ?mature? system dominated by water/rock interactions, though there is also evidence for magmatic contributions to the hydrothermal fluids. It is host to relatively high temperature (~300°C), focused venting of metal-rich fluids. Large Cu- and Zn-rich sulfide chimneys occur at this site, with high concentrations (up to 90 ppm) Au apparent in some chimneys. Vent fluids of the NW caldera site show sub-seafloor phase separation is occurring at this site. Silica concentrations in these vent fluids are consistent with the vent fluid temperatures. Secondly, there is the cone vent field that is much younger, and which sits atop the summits of a main cone (the Upper cone) and an adjacent satellite cone (the Lower cone) that occur inside the caldera, near the southern caldera walls. This field is dominated by S-rich vents with vent fluids more diffuse, lower in temperature (<120°C), very gassy and acidic (to pH 1.9), and relatively metal-poor. Fluids of the cone site have Mg and SO4 concentrations higher than seawater values, indicating these ions have been added to the hydrothermal fluid and are not being depleted via normal water/rock interactions. Variability occurs between the two cone vent fields, with the diffuse discharge observed at the Upper cone volumetrically small and chemically different from the Lower cone. For example, from the vent fluid Mn, Li, Rb, and Cs concentrations, it is apparent that the Lower cone has experienced a lower degree of water/rock interaction (i.e., more reaction) than the Upper cone. Vent fluid pH is higher for Lower cone, consistent with more reaction and neutralization of acidic gases. Fe/Mn is lower at the Lower cone due to decreased Fe solubility at the higher pH. The lowest pH sample (1.9) is from the Upper cone that has 39.4 mmol/kg of SO4, consistent with input of magmatic SO2 and disproportionation to sulfuric acid and S or H2S. Thus, the Upper cone site could be interpreted to have a shorter reaction path and residence time between the point of magmatic degassing and the seafloor venting than the Lower cone site. Isotopic compositions of the NW caldera and cone vent fluids show evidence for magmatic water with negative dD and d180 values, while 3He/4He values show the Brothers hydrothermal system has shifted towards more magmatic conditions over the past several years with both sites affected by magmatic events. Similarly, vent fluid sulfide d34S values and those for sulfide minerals from NE caldera chimneys also indicate disproportionation reactions involving magmatic SO2. Minerals such as chalcopyrite, bornite, chalcocite, covelllite and euhedral grains of hematite occurring in high temperature chimneys from the NW caldera site are consistent with a more oxidizing, magmatic fluid, while bulk sulfide geochemistry data show evidence for a higher temperature suite of elements (e,g., Mo, Co, Se) associated with Cu-rich chimneys. Gold mineralization occurs in these high temperature chimneys and is associated with the most recent deposition of high concentrations of Cu, where d34S values are most negative. Geophysical evidence suggests that the top of a magma chamber occurs ~2.5 km below the caldera floor, beneath the cone site in the SSE quadrant of the volcano. Very low velocities of <1 km-2 are seen in the seismic data between the magma and the seafloor, and are indicative of gas release. Harmonic tremor data provide evidence for a 500 m pipe-like ?conduit? located above the magma chamber (and below the cone), linking it with the overlying hydrothermal system, providing a mechanism for magma-derived metals to enter the hydrothermal system under the cone site. The NW caldera and cone sites are considered to represent stages along a continuum between magmatic-hydrothermal and water/rock-dominated end-members.

Jan 1, 2010

Research cruises dedicated to seafloor hydrothermal activity along the Kermadec arc first began with the Sonne-135 expedition in 1998. This was followed by the worldÆs first systematic survey for venting along an arc during the 1999 NZAPLUME I expedition. Since then, cruises dedicated to mapping plumes along the Kermadec arc include NZAPLUME II (2002), NZAPLUME III (2004) and ROVARK (2007). In addition, the manned submersible cruises SWEEP Vents (2004) and NZASRoF (2005) utilised the Shinaki 6500 and Pisces V, respectively, to sample in detail select hydrothermalsystems for mineralised samples, rocks and vent fluids. The ROVARK (2007) cruise was the first to deploy an autonomous underwater vehicle (ABE) along the arc which surveyed Brothers volcano at a far greater resolution than had been done previously by ships on the sea surface. While these expeditions have largely been led by GNS Science, together with its collaborators from National Oceanic and Atmospheric Administration, Pacific Marine Environmental Laboratory (NOAA/PMEL), significant contributions have been made by other groups from various nations, exemplifying the global interest in seafloor hydrothermal activity associated with intraoceanic arcs. This is an&nbsp;ASTRACT&nbsp;only.&nbsp;A full-length paper was not&nbsp;prepared for this presentation.

Jan 1, 2008

By Renliang Shan

Site conditions of China?s coal roadways are complex and changeable, and scientific classification of them is the fundamental basis for coal roadway support design, with great significance for ensuring proper roadway service. Upon analysis of the issues, a commentary regarding the research progress on classification of the stability of rocks surrounding coal roadways in China has been achieved from the point of view of classification methods and indexes. The shortcomings and applicable scope of rock stability classification methods related to coal roadways have been analyzed. It has been asserted that combining artificial neural networks with fuzzy mathematics, combining fuzzy mathematics with grey theory, applying new avenues such as support vector machine algorithms or unascertained average classification, and making classification indexes more scientific are future directions for development of rock stability classification for coal roadways.

Aug 1, 2013

By Alistair Burrows

Situated in the oblast of East Kazakhstan, the Ust-Kamenogorsk Metallurgical Complex has spent the past twenty years renovating and remodelling itself as a modern polymetallic sulphide smelting facility, and a regional centre of excellence for custom smelting. Along the way there have been changes to the company structure, introduction of new technologies, investments in expanded capacity, environmental improvements, and addition of new metal products and by-products to the site’s repertoire. These changes have been gradual and incremental, but taken together they represent a significant contribution to placing Kazakhstan’s sulphide smelting industry on a strong foundation for enduring success in the international custom smelting market. In achieving these changes, a workforce that was historically isolated from much of the world now has recognised expertise, internationally competitive skills, and confidence to embrace the future. Further improvements in energy efficiency, environmental compliance and polymetallic processing capabilities are challenges that UKMC stands ready to face.

By E. Oraby, S. Garcia, A. Thurgood, D. Bertoldi, G. O’Malley

Mining and Process Solutions (MPS) most advanced process, GlyCatTM is the only process that can be easily adapted to existing cyanidation plants in the market today whose real advantages over cyanidation are when treating copper containing ores, concentrates or tailings. With such complex material, GlyCatTM requires 70-90% less cyanide addition to achieve the same precious metal extraction. However, GlyCatTM is not simply cyanidation with added glycine. It is a completely different process where the solution chemistry and conditions needed to effectively leach the precious metals are quite different. Downstream however, the process is largely unchanged as the recovery of the leached gold and silver uses existing known processes such as conventional activated carbon or zinc cementation (Merrill-Crowe process). Another advantage is lower SCN, OCN, WAD and no free cyanide in the effluent which can substantially reduce cyanide detoxification requirements and decrease the OHS and ESG risk of the operation. This paper outline some of these differences and presents testwork, piloting and process examples to highlight the advantageous of this new process over conventional cyanidation.

Feb 1, 2023

By Ari Glazer

"Every year the tunneling business is expanding and collaboration with the International Society of City and Regional Planners (ISOCARP) for the future design of cities and urban communities is in the making. During the last half of this century, billions of people migrated to cities, and it is estimated that by 2030 almost five billion people worldwide will reside in urban communities. Hence, “Underground development will be an important tool in reshaping our urban areas to meet the challenges of the future without destroying their heritage or worsening their surface environment” (Esaki, 2005). In 2013, the Organization for Economic Co-operation and Development (OECD) estimated life expectancy to be around 80 years, meaning that in less than a decade we will need to bury billions of people in cities and urban communities, while trying to retain the deceased’s beliefs and customs. Religion plays a major role in our lives, and many people worldwide still decline to cremate their body after their death; therefore, cemeteries are essential for city inhabitants. Rites and traditions usually call for burials to be near the place of residence, which allows the remaining family members and friends to visit the grave frequently, at least in the first years. This is a challenge that urban designers and architects must confront while trying to solve the problems of future urbanization. In recent years, population growth, the rising cost of land and the extensive preservation of green areas have made cemeteries a burden and a nuisance, particularly for large cities and communities. Many graveyards that were once on the city's outskirts have become lifeless islands in populated areas (Fig. 1), rarely visited by the second and later generations. Cities worldwide face the challenge of allocating less land to maintain current burial practices. In response, some cities have begun to bury their dead at a great distance from the community; others have started to stacked burials, one on top of the other, while still others are constructing buildings and even skyscrapers for the practice of burial (Fig. 2)."

Jan 1, 2016

By B. A. Waite

The new OSH regulations concerning ground ward monitoring of underground coal mines has been the source of many concerns for the mining industry. Because the regulations were initially written at the federal level but are being administered at the state level, considerable confusion exists within the industry as to what is actually required. Based on the preparation and submission of over 30 monitoring plans for existing deep mines in Pennsylvania, West Virginia, and Ohio, we now have a very good feel for the detail the monitoring plans, as well as the costs to im plement the plans. We do not, however, feel confident in our evaluations of the long-term impact the ground water monitoring regulations may have on the industry.

Jan 1, 1980

By Wu Aixiang, Zhou Qian, Zhou Zaibo, Liu Juanhong, Wang Hongjiang

To improve the pumping capacity and engineering efficiency of fresh thickened tailings slurry, a high charge density superplasticizer was developed to improve the rheological properties of tailings slurry. The effects of superplasticizer content, the concentration and fineness of tailings, the proportion and type of cementitious materials, temperature, and hydration time on the rheological properties of unclassified tailings slurry and backfill materials were studied. The variation characteristics of the slurry yield stress, plastic viscosity, and thixotropy with different factors were measured by a Brookfield R/S-SST plus rheometer. The experimental results of fresh thickened tailings illustrated that the higher the concentration of the slurry and the finer the tailings, the worse the rheological properties of the slurry. The results of cemented paste backfill materials indicated that the rheological parameters increased as binder content and time increased. The rheological parameters decreased as the temperature increased. The addition of a superplasticizer reduced the rheological parameters and improved the rheological behavior of the fresh thickened tailings and cemented paste backfill materials, which was beneficial to the slurry’s pipeline transportation. This paper can provide technical guidance for slurry transportation in the backfill system and provide a reference for designing the superplasticizer used in tailings.

Jan 5, 2022

By Gary R. Corbett

The federally owned Cape Breton Development Corporation (CBDC) mines approximately 2.5-3.0 Mt of coal per annum from its Phalen Colliery. As part of an ongoing process to become more commercially viable the Corporation has implemented changes in its support method, namely, the transition from traditional steel set inseam supports to roof bolts as primary support in the single entry longwall retreat drivages. During 1991 and 1992, a monitoring program was implemented by the Cape Breton Coal Research Laboratory (CBCRL) to determine the loading on support systems and ground reaction in the gateroads in front of the retreating longwall faces of the 4 East and 5 East panels at Phalen Mine. The 4 East gateroad had been supported by steel sets alone. The 5 East gateroad had been supported by steel sets as well as roof bolting and strapping of the gateroad roof. Steel sets in both gateroads were instrumented with strain gauges and load cells to record support reaction to the retreating face abutment pressure. Multipoint borehole extensometers and multipoint strain gauged roof bolts were installed in the gateroad roof to monitor strata displacement and bolt loading above the gateroad as the longwalls retreated. This paper describes the details of the instrumentation and monitoring techniques utilized during this program and discusses the results, trends and differences observed in the two differently supported access roadways. Work on future data acquisition instrumentation is also briefly described.

Jan 1, 1993