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By Matej Petružálek, Tomáš Svitek, Tomáš Lokajícek

"Migmatite from the Skalka region (Czech Republic) was chosen as the experimental rock material. It has macroscopically visible plane parallel structure (foliation). The foliation was caused mainly by biotite grains arrangement. The cylindrical samples of migmatite with subhorizontal, subvertical and oblique foliation were uniaxially loaded up to the failure. Network of 8 broad band sensors was employed for acoustic emission monitoring and ultrasonic sounding. A grid search method with anisotropic velocity model was used for AE hypocenters localization. The source types of successfully localized events were determined from the average first arrival amplitude. Structural anisotropy of tested rock material caused the anisotropy of its mechanical properties (peak strength, Young’s modulus) as well as a different way of fracturing process in dependence on the angle between axial stress and foliation plane. The combination of splitting, shearing and sliding was found to control the fracturing of sample with subhorizontal foliation. The shearing and sliding was dominant in fracturing of samples with oblique foliation. With greater dip of foliation, the role of sliding increased at the expense of shearing. Due to the favorably oriented system of microcracks already present, the shearing and splitting was at the same level during fracturing of the sample with subvertical foliation before nucleation began.INTRODUCTIONThe process of failure of low porosity rocks depends on their mechanical properties and actual stress and temperature condition. At the low pressure and low temperature, the most common way is brittle failure, which is a progressive process requiring the initiation, growth and coalescence of cracks (Lockner, 1993). Stress strain behavior of low porosity crystalline rocks, during the laboratory compression experiments, is divided into four characteristic stages: crack closure, elastic region, stable crack growth and unstable crack growth which leads to the brittle failure, Brace et al. (1966) , Bieniawski (1967), Lajtai (1974), Cai et al. (2004), Nicksiar and Martin, 2012 and 2013.The fracturing process of stressed rock begins with the crack initiation (sci), which for low porosity rocks occurs approximately at 40-50% of peak strength (sp) (Cai et al., 2004; Nicksiar and Martin, 2013). After the sci, the dilatancy begins and stable crack growth follows up to the crack damage threshold (scd), which is approximately at 80% of sp (Cai et al., 2004). After crossing the crack damage level, there is an unstable crack growth accompanied with nucleation of fault plane (sn) at 97-100% of sp. (Rao et al., 2011). The stress drop accompanied with formation of macro scale shear failure plane follows after peak stress is crossed."

Jan 1, 2015

By Walter Voglauer, Elisabeth Zechmeister

Description of Project: The four photos show a chimney blasting operation in Vienna’s district of Floridsdorf on May 4 2011. The blasting was done with two types of charges. An internal charge provided a force of blast which resulted in 135 single electrical blasting caps initiated detonations on the basic ensured the straight collapse of the chimney. The preparation work was done by reserve force military engineers. The series of photos were shot by Elisabeth Zechmeister. She works in the Austrian DOD but not as a professional photographer; much more she did all activities in her spare time.

Jan 1, 2013

By G Williams

Discussing equipment, systems of work, the need for updated programmes of local seismic exploration, and developments within the South Wales coalfield.

Jan 1, 1993

By John E. Crawford

A year ago, if I had the pleasure of addressing you, I would have discussed ocean mineral resources from a promotional standpoint. I would have described exciting indications of mammoth tonnages of sea-floor industrial minerals. I would have attempted to fire your imaginations as to the potential of a nation having the technologic know-how to exploit its submerged boundaries. As a first step toward this capability, I would have solicited your support for a Bureau of Mines? program aimed at determining the industrial worth of marine minerals and devising techniques and hard- ware for their recovery. We still need your support, but recently we have ventured out of the realm of planning and into your Government's first program in marine mineral engineering. Today, I wish to describe what we have done within the framework of existing research problems and our possible goals. I will be brief so as to allow ample time for questions, and I can do this with confidence because our program is so new that I need not be chagrined at not having all the answers.

Jan 1, 1965

By Thomas T., Read

ANY discussion of State-supported schools of mining and A metallurgy needs to be prefaced by a definition, since the first school to offer a mining curriculum, the Pennsylvania Polytechnic College, was established by a grant from the State. But, so far as can be determined, it received no further State support. It would be tiresome to go into precise details,. and it will be enough to stipulate that by State schools are meant those which derive their main financial support from regular appropriations made by a State legislature. The University of Michigan was the first of these to offer a mineral industry curriculum; its story, as well as those of Wisconsin and Illinois, has been related in the preceding chapter.* Arranging the others in chronological order involves making a decision as to what weight to attach to plans for giving instruction, as contrasted with its , effective initiation. This may appropriately be illustrated by the history of mineral industry education in California. California Among those who came to California in 1849 and the following years were many New Englanders who had a keen interest in education. Some of them, mostly Congregationalists and Presbyterians, sought to establish a school of higher education around San Francisco Bay and eventually succeeded in opening the "Scientific and Classical School at Contra Costa' in Oakland, at Broadway and 5th St., on June 20, 1853. This prospered so well that it was chartered by the State as the "College of California" on April, 13, 1855. Developing so rapidly that its quarters became cramped, in 1864 it not only bought a tract of

Jan 1, 1941

By Robert Halupka

The industrial minerals sector represents a broad range of products involving a variety of technologies serving a diversity of markets and end uses. Unit values of products vary widely, reflecting the peculiarities of each product/market sector. Generalizations are therefore understandably difficult to make and borrowers may need to take extra time to "educate" lenders on the key aspects of their business and industry sub-sector. This paper will examine the factors and the thinking that lenders apply when considering financing proposals to companies in the industrial minerals sector. If you understand the lender's perspective and their concerns, then you can make better use of your own time and resources when arranging financing for your company or project.

Jan 1, 2001

By Carla J. Moore

The National Geophysical Data Center (NGDC), Marine Geology and Geophysics Division and co-located World Data Center-A for MGG archives and distributes global marine sediment data from U.S. and international sources. NGDC is part of the U.S. Department of Commerce, National Oceanic and Atmospheric Administration (NOAA), National Environmental Satellite, Data, and Information Service. NGDC offers a variety of digital marine sediment data sets including sediment descriptions, textural analyses, geochemistry, paleontology, paleomagnetism, and well logs. Some data sets are compiled by outside sources and sent to NGDC for distribution; many are received under exchange agreements and through the World Data Center system. Other data sets are compiled at NGDC, frequently in cooperation with other government agencies or academic institutions. One of the best examples of the latter is the Index to Marine Geological Samples, or "Core Curators' Database".

Jan 1, 1993

By Frederick W. Lee

List of contributing editors of Geophysical Abstracts:

Sep 1, 1932

By Oswald J. Heinrich

This question having been repeatedly raised, and particularly revived in a discussion at the last meeting of the Institute, I beg to submit the following remarks, based partly upon personal experience, partly upon the results of large works in Europe, establishing, years ago, the practicability of certain methods, which may therefore be considered to have passed the stage of mere experiment. Before entering upon the merits of one system or the other, it is indispensable to lay down some recognized principles, which ought to serve as guides, in arriving at fair judgments in questions of this character. In a profession like that of mining, locally so much influenced by combinations of circumstances too various to mention, it is difficult to do more than lay down the main features of a system based upon general laws and recognized facts, leaving the details to the sound judgment and experience of the engineer, who, by virtue of his education, ought to be able to make such choice and such modifications in the plans of a mine as the particular case demands. Mineral resources, in some countries the sole property of the owner of the soil, in others controlled by the strong hand of a government, are nevertheless a gift of nature, in which, indirectly, the whole of the human race has as real an interest as the immediate owner himself. This interest requires, at least, that no unnecessary waste of

By Manis Kumar Jha, D. D. Pathak, Archana Kumari

Treatment of secondary/waste to recover rare earth metals (REMs) is gaining importance due to its increasing global demand, lack of availability of high grade natural resources and huge generation of secondaries. Present paper reports the critical review on available processes for recovery of REMs from secondaries viz. manufacturing scraps, e-waste, industrial residues such as red mud, fly ash, waste water, etc. Hydrometallurgical processes with combination of Beneficiation/ Pyro-/Electro techniques are discussed to recover REMs effectively. The recommended processes require less energy to deliver high purity yield which is one step towards green environment. Salient findings on various methods are reported with recommendations which will be helpful to researchers working in the area of REMs extraction.

Mar 1, 2018

By Ballard H. Clemmons

THE future of the steelmaking industry of the Birmingham, Ala., district is closely related to and, in a large measure, dependent on the development of workable, economic processes of ore concentration. Operations thus far in the area have been possible only because of the fortuitous occurrence of iron ore, fluxing stone, and coking coal-all the primary iron-making materials within a 25-mile radius of the blast furnaces.

Jan 12, 1950

Contractors are used extensively in the development of underground mines in Australia. Often problems arise, some originating as far back as the feasibility stage of projects, through inexperience, lack of preparation and inflexibility by both parties.Guidelines are put forward for both principals and contractors which are seen as necessary to ensure that disputation is avoided and the full benefits of the use of contractors are obtained.

Jan 1, 1985

By D. Harrington

Part III-B, presented in this circular, completes the series reviewing the literature on effects of breathing dusts with special reference to silicosis; it includes data on the status and cost of compensation for silicosis in the United States and several foreign countries and a summary and general conclusions covering the whole series. Parts I, II, and III-A of the series have been issued as Information Circulars 6935, 6840, 6948 , and 6957; Part I defines and classifies dusts, indicates sources of exposure, and describes the physiological effects of breathing dusts; Part II-A discusses the principal dust factors producing pulmonary pathology and methods of determination of dust in air; Part II-B presents data on the engineering and medical control in the prevention of dust diseases and general recommendations for their control in industry; and Part III-A deals with the economic and legal aspects of dust diseases in industry.

Jan 1, 1936

By M. H. Kline

The Great Gossan Lead in Carroll County, Va., is one of the largest undeveloped sulfide ore bodies known in the eastern United States. It extends for 16.7 miles along the western slope of the Blue Ridge Mountains (fig. 1). The various known segments of the deposit, extending from the southwest end to the northeast, are: The Great Outburst or Iron Ridge segment, Chestnut Creek, Copperas Hill, Sarah Ellen, Wild Cat, Cranberry, Dalton Hill and offset segment to the south of the Cranberry, Little Reed Island, Little Vine, and the Betty Baker at the northeast end. All of these segments have been explored or mined to various extents in the past for the iron gossan and secondary copper ore. The Great Outburst or Iron Ridge segment is now being mined by the General Chemical Division of the Allied Chemical & Dye Corp. for the sulfur and iron content of the primary ore. These deposits are becoming increasingly of Interest as a. large potential source of iron and sulfur owing to their proximity to Birmingham, where the burned cinder sells at a premium, and to the acid markets of the region.

Jan 1, 1949

By David Verrelli, Melissa Kistner, Leanne Smith, Chris Aldrich, Lidia Auret, Warren Bruckard

In this investigation, different mixtures of realgar and orpiment particles were floated in a laboratory batch flotation cell and multivariate image analysis was used to estimate the arsenic content in the froths. The analysis was based on the froth colour, as well as extraction of three groups of textural features, namely those based on grey level co-occurrence matrices (GLCMs), wavelets and local binary patterns (LBPs). Collectively, these features provided better information on the arsenic content of the froths than any one of the individual groups of features. Partial least squares models could explain approximately 78% of the variance in the arsenic by using all the features combined. The colour content, particularly the green component in the red-green-blue (RGB) features, provided almost as much information as each of the three sets of texture-base features individually.

Jan 1, 2014

By R Jacobs, J Yeates

"The Stockman base metals project is situated in State Forest in the alpine area of East Gippsland, Victoria, adjacent to a National Park and within the headwaters of a major Ramsar-listed wetland catchment and the Murray-Darling River system. Site topography is steep, and elevated (650 m – 1200 m above sea level), and subject to circa 1 m annual rainfall, with occasional winter snowfall. The project consists of two volcanogenic massive sulfide (VMS) deposits to be mined by underground methods and treated in a 1.0 Mt/a central concentrator to produce copper and zinc concentrates for export over a ten year operational life. New resource projects are rare in Victoria. Recognising the sensitive setting, planning for the Stockman Project, which is now in the advanced permitting stage, has focused on balancing economic, environmental and social outcomes to ensure social licence to operate is secured and can be maintained. This has involved close attention to triple bottom line (TBL) risks and outcomes. Stockman has successfully gained State and Federal approvals via the Environmental Effects Statement process. The process of obtaining these approvals has required close attention to effective stakeholder involvement, and management of a lengthy and difficult approvals process, which is still to be finally concluded. This paper is a case study of the process of that permitting and the issues encountered to date. Key learnings from the experience have included: successful approvals require close attention to much more than just the project and its technical aspects and physical setting – effective stakeholder involvement and endorsement is critical the differing consultation requirements for local, regional and government stakeholders, to design and plan implementation of a project to meet TBL objectives, and to gain social licence to operate within the Victorian approvals process, the need for an effective lead government agency with policy authority dealing with material policy change requiring post-closure financial sureties estimating realistic permitting time and cost during the project evaluation phase. CITATION: Jacobs, R and Yeates, J, 2016. Stockman base metals project – sustainability, social licence to operate and permitting lessons learnt, in Proceedings Project Evaluation 2016, pp 98–110 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 8, 2016

By R Norris, M Dunne

Substantial efforts by the industry, as well as by process and equipment designers, have resulted in many innovative developments that provide cost effective reductions in water usage. This paper showcases four emerging best practices in industry including examples of recent installations. Belt press filters are a small fraction of the operating and capital cost of alternative ædryÆ tailings technologies. This gives operators who must ædryÆ their tailings a competitive advantage and makes such operations much more sustainable. The new generation of belt filter presses use less energy, produces lower cake moistures and better disposal stacking properties. The need for tailings storage facilities may be eliminated or in some cases high-grade tailings can be dewatered and sold as a low value product. Mining applications include sand tailings, sinter plant waste, coal tailings and power station fly ash. Flip-flow screening machines are proven worldwide in the dry classification of coal and other minerals, reducing the size of beneficiation plants, whilst reducing energy, water demand and media consumption. They also allow the screening of wet/sticky materials not able to be sized using conventional screens. Lamella separators are used for toxic water clarification and/or sludge thickening in many downstream metal industries with the underflow often dewatered in a belt filter press. Such low cost, high capacity thickeners could also be used instead of conventional thickeners at smaller mines. The simple and reliable continuous washing upward flow (CWUF) sand filters have been used for treatment of waste water from coal preparation plants and steel works as well as in the production of potable water. The filtered waste water from mining processes can then either be reused or discharged from site. Other installations include cleaning mine water to prevent the blocking of dust suppression spray nozzles.

Jan 1, 2006

By S Liu, N M. Rana, A Take, N Ghahramani, D Clohan, S McDougall, S G. Evans, H J. Chen

Tailings dam breaches have caused significant life loss, social, economic and environmental damage in recent years. The term "tailings-flow" refers to various forms of tailings outflow movement resulting from the breach of a tailings dam. These flows, comprising a mixture of tailings, water and dam materials, can take different forms, ranging from a debris flood to a flowslide, and can travel long distances and impact large areas. The inundation extents depend on the failure mechanism, tailings dam height, total released volume, sediment concentration (associated with the rheological behaviour of the flow) and downstream conditions (including topography, land cover and presence of a water body). Numerical runout modelling of tailings dam breaches is important for predicting the dynamics and extent of tailings-flows, which are crucial steps in tailings dam consequence analysis and risk management. This paper presents a comparison of numerical simulations of the 1994 Merriespruit tailings dam breach using three numerical models: DAN3D, FLO-2D and MADflow3D. Using compiled site condition information and data from the literature and public domain, model performance was evaluated primarily based on comparisons between the observed and simulated inundation extents. The main purpose of this preliminary model benchmarking exercise was to help us evaluate the capabilities and limitations of each model, and to identify opportunities for future model improvements as part of a broader research initiative known as CanBreach. This exercise also highlights the inherent complexity of tailings-flows and the importance of using judgement to interpret model input and results.

Jul 1, 2021

Discussion, at the Virginia Beach Meeting, February, 1894, of the Paper of Prof. Posepny. (Trans., xxiii., 197, 587.) Including communications subsequently received. a T. A. Rickard, Denver, Colorado (communication to the Secretary) : The paper of Professor Posepny was printed so short a time

Jan 1, 1895

By John Ward Smith

Aragonite, co-occurring with calcite and dolomite as matrix minerals, has been discovered in Mahogany zone oil shales of Colorado's Eocene Green River Formation, posing puzzles on the geochemical patterns of their separate origins, reasons for their simultaneous existence, and their interrelation. The presence of aragonite is demonstrated by X-ray diffraction. Amounts of aragonite and dolomite are significantly and inversely related, but the calcite quantity is essentially independent of either aragonite or dolomite quantity. A geochemical pattern outlining the deposition conditions that created the Green River Formation oil shale is postulated from characteristics of the oil shale. The development of the three separate carbonates--aragonite, calcite, and dolomite--the inverse relationship between aragonite and dolomite, and the independence of amounts of calcite and the other two carbonates are shown to be natural consequences of this oil-shale genesis pattern.

Jan 1, 1973