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By F. N. Earll

4.1 – DEFINITIONS 4.1.1-MINERALS, ROCKS, ORES AND NONMETALLIC MINERALS F. N. EARLL A mineral is a naturally occurring inorganic element or compound. Most minerals are distinctly crystalline in habit, and many commonly occur in well-formed crystals or crystalline aggregates, but a few species are characteristically amorphous or noncrystalline. Nearly 2,000 mineral species are now recognized but, perhaps fortun¬ately, a rather large proportion are rarely encountered. Even so, the application of modern mineral-detection and identification techniques reveals the presence of surprising numbers of mineral species, even in deposits of outwardly simple mineralogy. A rock is an aggregate of grains or crystals of one or more minerals. Some rocks are essentially monomineralic. Thus, limestone consists largely of the mineral calcite, and many sandstones are dominantly quartz. Most rock varieties, however, contain a number of mineral species, and their classification or identification depends upon the minerals present, their relative abundance, and such factors as rock tex¬ture and origin. Ore is defined as an accumulation or deposit of one or more minerals that can be exploited at a profit. The profit criterion commonly is taken somewhat liberally, however, for, although always present, the specific mineral content that constitutes a viable product is transitory. The term ore, usually, but no longer consistently, is restricted to the description of mineral deposits that are of value for their metal content. Nonmetallic deposits, although similar to metallic ores in many respects, generally are valued for the minerals or compounds present, as with rock salt (halite), rather than for individual contained elements, though such minerals as elemental sulfur are of much value. 4.1.2-ROCK TYPES F. N. EARLL Rocks arc grouped tinder three broad headings: (1) igneous rocks formed by the crystallization of magma; (2) sedimentary rocks formed by surface processes of weathering and deposition; and (3) metamorphic rocks, which may have been derived from either of the foregoing, but have undergone important physical and/or chemical changes through the application of heat or pressure, or both. The three groups can he further subdivided for convenient reference. Thus, igneous rocks are described as being abyssal or plutonic if formed at great depth, hypabyssal if formed at intermediate depth, and extrusive or effusive if formed at or on the earth's surface. The sedimentary rock group is similarly subdivided into clastic sediments and chemical precipitates. The clastic sediments form by deposition of preexisting minerals that were released from their place of origin by weathering and were transported to their point of deposition as discrete grains

Jan 1, 1973

By J. B. Knapp, J. W. G. Betts, Scott L. Burreill, J. H. Bassarear, E. A. Lowe, W. J. N. Davis, John L. Bolles, Gaylord P. Dopson, William H. Keener, N. S. L. Steenkamp

This chapter contains moderately detailed descriptions of some typical and well known mills that treat predominantly sulfide copper ores, some containing secondary values in gold, silver, and molybdenum. The descriptions are general in nature, because most of the specific data will be found in tabulations elsewhere in this section, covering a large number of mills in such matters as flotation reagents, crushing and grinding equipment and steel consumption, thickener and filter operating data, power consumption, and many others, in a manner that the reader will find convenient and comprehensive for reference and comparison. On the other hand, the plant descriptions selected for this chapter emphasize the kind of information that cannot be readily tabulated.

Jan 1, 1985

By Charles Kimbell, L. Nahai, E. Shekarchi

INTRODUCTION AND SUMMARY World mineral trade during 1960 to 1984 has shown substantial changes both in value and tonnage. Although fuel commodities dominated total mineral trade during this period, this paper will focus attention primarily on nonfuel minerals. Brazil and Australia, modest producers of iron ore in 1960, have become dominant producers and exporters, together accounting for about half of major iron ore exports in 1984, far surpassing traditional export suppliers such as Sweden. Australia has also become the largest producer and trader of bauxite and alumina, and worldwide alumina trade has increased at the expense of bauxite trade. Similarly, shipments of ferroalloys have increased more than shipments of ores such as those of chromium and manganese. Canada, retaining its first rank in world export of zinc, has become also the leading source of potash and sulfur in world trade, and South Africa has been the dominant factor in chromite, manganese and their respective ferroalloys. Developing countries' share of world copper trade has increased, with Chile maintaining first rank, but developed industrialized countries have continued to dominate production and trade of lead and zinc. Phosphate, sulfur, and potash have been the principal crude nonmetallic minerals traded worldwide. Looking to the near future, dramatic increases in export of iron ore, phosphate, potash and sulfur are not envisaged. Bauxite exports will continue to decline relative to alumina but at a slower rate than in the recent past. Zinc concentrate will continue to be exported but lead will be traded more as metal than as concentrate. For iron and steel, there will be some production shift from traditional producers to certain developing countries and recently industrializing developing countries such as Brazil, India, the Republic of Korea, and Taiwan. In the following sections dealing with specific commodities, it should be understood that information is presented only on the major forms of each commodity that move in trade, and only for a selected group of countries for each commodity or major form of each commodity. Thus, totals shown or mentioned generally represent only the totals of figures presented here and do not include estimates for minor forms of material or for countries that are not listed. However, the data provided is regarded as sufficiently complete to reflect major patterns and trends, and exclusions are there- fore not seen as affecting conclusions that may be drawn from the material provided. FUEL AND NONFUEL TRADE Values of Fuel and Nonfuel Trade The value of world export trade in major mineral commodities (ores, concentrates and scrap, crude minerals, iron and steel, nonferrous metals, nonmetallic minerals and mineral fuels) in 1983, the latest year for which comprehensive data are available, was reported by the United Nations in May 1985 to have totaled over 514 billion current U.S. dollars (Table 1). This was 79% of the historic record high of nearly $649 billion ,current dollars set in 1980, but almost 18 times the current dollar value reported for 1960. [1/] The value of these 1983 exports in constant 1960 dollars was $164 billion (Table 2), only 66% of the record 1980 high of almost $250 billion, and only about 5.7 times the 1960 dollar level.

Jan 1, 1986

By Ulrich Maidl

The use of EPB shields in the so-called mixed face conditions has set new demands to man and machine in EPB shield tunneling. EPB shields were initially conceived to drive in the pressurized closed mode in soft ground, whereas hard rock TBMs were designed to work in the unpressurized open mode. The present use of EPB shields in hard rock and mixed face conditions requires the combination of both technologies by finding best compromise solutions. This paper deals firstly with the geotechnical and mechanical interactions between machine and ground. Further on the critical points such as tool wear and tool replacement are exposed, together with a proposal of best solutions.

Jan 1, 2003

By Gareth Mainwaring

The Cross Harbor Freight Movement Project is currently in the Environmental Impact Statement phase. The scheme is addressing alternative solutions to transport freight across the Upper Bay of New York Harbor, from New Jersey through to Brooklyn, Queens and Long Island. Amongst the alternatives being assessed are two tunnel options; from the north shore of Staten Island through to Brooklyn, and from Jersey City to Brooklyn. These tunnels are approximately 30,000 feet in length, and with up to17,000 feet under the Harbor, would make it one of the longest undersea crossings in the world.. The paper addresses the development of the project, from the Major Investment Study through to the current EIS, and describes the tunnel schemes that are being taken forward. The geological conditions that will be encountered, proposed construction methods, and the ventilation issues associated with such major undersea tunnels will all be described.

Jan 1, 2003

By M. T. Worley

Joint Development Associates International, Inc. (JDA) began humanitarian relief and community development in Central Asia in1992, following the collapse of the former Soviet Union. Appropriate technology has played an important role in their efforts to assist those segments of society that are most vulnerable to poverty and disease. Three case histories are described to illustrate the successful implementation of simple, but effective technology in community development.

Jan 1, 2004

By Richard W. Kimball, Fred B. Estep, Dwayne E. Easterling

This paper discusses the overall challenges to construct a 15,125.7 m (49,625 LF),wastewater drainage tunnel in Cobb County, Georgia by a joint venture of Gilbert Southern Corp. and S.A. Healy Co. and a construction manager Parsons, with Jacobs Associates as a subcontractor. The goal of the project is to provide wastewater retention during peak usage and is connected to a treatment facility near the Chattahoochee River. The primary component of the project is the TBM-driven hard rock tunnel. Additional works include drill and blast areas; four intake interceptors, two construction shafts and a 33.5 m (110 ft), diameter pump station shaft.

Jan 1, 2003

By C. Cigna, M. Patrucco, D. Savoca, E. Lovera

The paper deals with the activity program and the preliminary results of a research work commissioned by IReR Research Centre and Regione Lombardia to the Department of Land, Environment and Geotechnologies of Politecnico di Torino. The aim is to define measurement, analysis and control criteria for the emission of chemical and physical pollutants from non-metal mining industries, with particular reference to noise and airborne particulates. Such emissions are related to health risks and annoyance problems, both for the working crews and the neighbouring population, and so, in order to get an effective sustainability of the industry, suitable reduction methods and assessment tools are required. A simple technique for the evaluation and forecasting of both the emission levels and deriving impact has been tested at different mining and quarrying sites, considering their differences in terms of layout and exploitation method, the latter ascribed to a series of main typologies as present in Lombardia region.

Jan 1, 2005

By Michael Deutscher, Jozef F. Zurawski

Part of Capital Improvement Project SE-754 tendered by New York City Department of Design and Construction included installation of a 96-in. (2.47 m)diameter sewer by pipe jacking methods. The pipe selected by the Contractor, EIC Associates, Newark, New Jersey, was a glass-fiber-reinforced thermosetting resin pipe installed in two reaches: 72 m (235-ft.) and 222 m (728-ft.). The machine selected for the excavation was an open face shield. This paper describes the set up of the tunneling operations, subsurface conditions, progress of excavation, pipe performance and other details of the project including unexpected difficult ground conditions that were encountered during excavation and how these conditions were overcome.

Jan 1, 2003

By Gennaro G. Ph. D Marino

In order to improve handling of subsidence damages the Illinois Mine Subsidence Insurance Fund supported the development of novel cost-effective methods of repair. The research in developing the repairs was directed towards the most common and costly damages that had been observed. As a result repair techniques were designed for structurally cracked foundations in the tension zone; structurally cracked foundations in the compression zone; and damaged or undamaged tilted foundations. When appropriate, the postulated methods would result in: 1. significant cost savings (over conventional procedures); 2. a structural capacity greater than when the foundation was untracked; and 3. an aesthetic appeal. All the postulated repair methodologies were laboratory and/or field tested. The paper will summarize the essentials of each technique developed and the test results.

Jan 1, 1986

By M. Fornaro

A small size quarrying activity (3 different quarries with an overall production in blocks less than 10.000 m3/year) has been exploiting for a long time the ?Tonalite? deposit of Adamello-Presanella. In 1967, given the outstanding natural beauty of the area, a natural park has been established with the aim of preserving environmental quality and, at the same time, of providing a sustainable development to the area. Because of the potential impacts of a mining activity in such a context, a specific study has been recently carried out in order to define if and how the quarries could co-exist with the park, beyond the ?administrative results? of a classic environmental impact assessment. The paper deals with the process that drove to the conclusion that the activities are not ?a priori? incompatible with the aims of the park. In the opinion of the authors, a responsible quarry management, which must take inspiration from the care given to environment by traditional alpine productive activities (e.g. the use of water, of wood, and of the stone itself), and take advantage of modern technologies in terms of emissions and safety, can be considered not only compatible with the protected area, but even able to positively contribute to the protection of the land and environment (Barisone et al., 2001). A series of specific prescriptions, which have been adopted by the Park Authorities after this study, are also discussed in the paper: only the definition of suitable spatial and temporal limits, the adoption of effective technical practices and a strict control are considered to be able to drive this ?exceptional? activity towards the final goal of real sustainability.

Jan 1, 2007

By Robert A. Bauer

Two basic types of subsidence occur in Illinois: pit and sag / trough. Pits develop over mines less than 165 feet deep and where relatively incompetent strata are found over the mines. Sag subsidence is found over mines as shallow as 75 feet and more generally over mines of greater depths. The percentage of subsidence and angles of draw associated with sag subsidence appear to be controlled by the rock properties at each specific site. The percentage of subsidence and angles of draw are smaller where the sites are not affected by geologic structures. An investigation to determine if a time factor based on the time interval from the date of mining to the subsidence events has shown that simple correlations with time, percent extraction, average pillar stresses, and pillar dimensions is not evident in Illinois.

Jan 1, 1982

By W. M. Ma, Daniel W. H. Su, K. Centofanti, Yi Luo, W. L. Zhong, Syd S. Peng

4.1 INTRODUCTION There have been numerous methods developed for predicting the final subsidence and final displacement profiles (Voight and Pariseau, 1970; Brauner, 1973a; Kratzsch, 1983). But for discus- sion purposes, they can be classified into six categories: theoretical, profile function, influence function, graphical, physical, and numerical modeling. The theoretical method employs mainly continuum mechanics theories and attempts to explain the mechanisms that lead to sur- face subsidence. Many models using nearly all kinds of material behavior have been developed. These include elastic (Salmon, 1963; Berry, 1964), plastic (Pariseau, 1968), viscoelastic (Iman, 1965), and elastoplastic (Dahl, 1969). The Profile Function Method is essentially a method of curve-fitting against the measured subsidence profiles in a particular mine or region. There are more than 20 profile functions developed empirically for nearly all major coalfields in the world. These include, to name just a few representative ones: Hungary (Martos, 1958), Japan (Hiramatsu and Oka, 1968), Russia (Avershin, 1947), United Kingdom (Wardell, 1965), and USA (Peng and Chen, 1981; Karmis et al., 1984). The NCB's graphical method in the subsidence Engineers' Handbook (1975) also belongs to the profile function method. The influence function method was first proposed by Bals (1931/1932). It was further developed in various periods and stages by Knothe (1957), Liu and Liao (1965), Brauner (1973a) and Marr (1975). This method is now widely used in various parts of the world. The physical models include sand (Litwiniszyn, 1959; Pariseau and Dahl, 1968) and gelatin (King and Whetton, 1958; Khair et al., 1986). They are used mainly to study the parameters that control subsidence behavior. The most popular numerical method is the finite element technique. It can simulate nearly every conceivable material behavior, inhomogeneity, bedding planes, anisotropy, and various boundary conditions. This versatility is absolutely necessary considering the ever-changing geologic and mining conditions encountered. In the following sections, only those methods that have been applied to US coalfields will be discussed. Furthermore, the methods for prediction of several key parameters such as maximum subsidence, maximum possible subsidence, and maximum displacement are discussed first, because they are the key parameters to be used in the profile function, influence function, and graphical methods.

Jan 1, 1992

By David A. Holmes

Zeolites are crystalline, hydrated aluminosilicates of the alkali and alkaline-earth metals. Their crystalline framework is based on a three dimensional network of SiO4 tetrahedra with all four oxygens shared by adjacent tetrahedra. The alkali and alkaline-earth cations are loosely bound within this framework structure and may be exchanged, to varying degrees, with other cations or molecular water. Most zeolites can be reversibly dehydrated. At present, close to 40 natural zeolite minerals have been identified and over 100 zeolites have been synthesized. Zeolites are a family of hydrous aluminosilicate minerals whose physical properties provide unique features for a wide variety of practical applications. Zeolites have been known for more than 200 years, but it was not until the middle of this century that their economic potential and widespread occurrence in sedimentary rocks were known. Since 1950, literally thousands of articles and patents have appeared in technical literature, and commercial pro¬duction of natural zeolites may now exceed 1 Mt worldwide an¬nually. In the past 40 years, the zeolite mineral group has changed from that of a museum curiosity to one of an established industrial mineral commodity. According to Breck (1974), zeolites are characterized by the following properties: 1) High degree of hydration, 2) Low density and large void volume when dehydrated, 3) Stability of the crystal structure of many zeolites when dehydrated, 4) Cation exchange properties, 5) Uniform molecular-sized channels in the dehydrated crys¬tals, 6) Ability to adsorb gases and vapors, 7) Catalytic properties. All zeolites are molecular sieves, but not all molecular sieves are zeolites. Activated carbon, activated clays, alumina powder, and silica gels are also molecular sieves. Molecular sieves are materials that can selectively adsorb molecules on the basis of their size, shape, or electrical charge (Clifton, 1987). Commercial application of zeolites is based on the following physical properties: molecular sieving, ion exchange, adsorption, and catalysis. Potential commercial utilization includes hundreds of possible applications. The principal uses at this time, however, are as fol¬lows: -Ammonium-ion removal in waste stream treatment, sewage treat¬ment, pet litter, and aquaculture, -Odor control, -Heavy metal ion removal from nuclear, mine and industrial wastes, -Agricultural use, such as soil conditioner and animal feed supplement. An estimated 800 kt to 1 Mt of natural zeolites were produced and consumed worldwide in 1991. Eight small operators reported collective production and consumption of an estimated 18 kt of natural zeolites in the United States during 1991, mostly for feed additives and for odor control, aquacultural, agricultural, catalytic, and ion exchange applications (Eyde, 1992).

Jan 1, 1994

By Terry Owen

Not since 1917 has a foreign company developed a standalone, grass roots gold mine in Russia. With Russia's political changes of the late 1980s, development of mineral prospects once again beckons foreign investors. Cyprus Amax's interest in Russia began before the mid-1991 breakup of the former Soviet Union. In 1990, Cyprus Amax began searching for such an opportunity. Early this year, production will begin at the Kubaka gold project located in the Russian Far East, near the Arctic Circle. The Kubaka project is a 1.75-kt/d (1,930-stpd) open-pit operation that will produce more than 9.3 t/a (300,000 oz/year) of gold. Identifying Russian mining opportunities In late 1990, the first Cyprus Amax people travelled to Russia. The trip was to determine the potential for western firms to develop profitable mines. This encouraging visit suggested that Cyprus Amax focus on the Russian Far East with its mineral riches and its easier access to the United States. The company's initial efforts thus focused on working with the Soviet Union's Northeast Geologic Expedition, the then government agency for exploration and geology in Russia's Far East. After the breakup of the Soviet Union, Cyprus Amax continued working with the same people, but they now represented new independent, nongovernmental entities. For three years, Cyprus Amax investigated numerous deposits. This resulted in the identification of two properties of significant interest, one of which was Kubaka. Location Kubaka is located in the Northern Evensk District of the Magadan Oblast in the Russian Far East. This is an area east of Siberia. The project is situated in a mountainous area of the Kolyma Range, about 300 km (985 miles) south of the Arctic Circle. It is 285 km (180 miles) north of the fishing village of Evensk and 380 km (235 miles) northeast of the silver-mining town Omsukchan. The site is 950 km (590 miles) northeast of the regional capital city of Magadan. Magadan, the political and economic center of the Oblast, has a population of about 150,000 people. It is served by a year-round deep-water port (with icebreaker assist) and an international airport with service to Moscow and Anchorage, AK. Access to the Magadan region

Jan 1, 1997

By K. L. Browne

After a decade of high copper prices, major mining companies are renewing their interest in purchasing operating properties and/or developing ore bodies. An existing operation carries with it a history that can present unique opportunities, while a greenfield operation allows for the establishment of a defined culture. Capital investments are distinctly different. A comparison of BHP Copper's Robinson operation, a greenfield property, and BHP Copper's Tintaya operation, a government owned Peruvian property, will provide insights into mining, concentrating and cultural differences between North and South America operations. The Broken Hill Proprietary Co. Ltd. (BHP) is Australia's second-largest company. Fiscal year 1996 sales were US$16 billion, profits were more than US$1 billion and total market capitalization was about US25 billion. In 1885, BHP began mining silver, lead and zinc at Broken Hill, New South Wales, Australia. Throughout its 112-year history, BHP achieved an impressive record of performance and expansion. Today, BHP is one of the world's leading companies (66th on the Standard and Poors 500), having diversified into steel, petroleum and mining with more than 65,000 employees in 70 countries.

Jan 1, 1997

By Marco D. Boscardin

During subsidence, the ground surface may settle, change slope, change curvature, go into tension, and/or go into compression. In response to these ground movements, buildings and buried utilities in the subsidence area may settle, tilt, bend, distort, and sustain extension, compression and/or torsion. In order to develop measures to protect existing structures and utilities, or to design new structures and utilities to withstand potential movements in areas of subsidence, it is necessary to understand the interaction between the ground and the building or buried the utility. This paper reviews subsidence-induced ground movements, how these ground movements are transmitted to and accommodated by buildings and buried pipelines, and how these structures may alter ground movements relative to free field subsidence-induced ground movements.

Jan 1, 1986

By J. Herbst, J. A. Kitchner, J. P. Anfruns, G. Poling

Measurements have been made of the rate of capture of single particles of strongly hydrophobic, surface-methylated, quartz, of sizes ranging from 12 to 40 pm diam., by single rising bubbles of diam. 0.5 to 1.1 mm. The results agree closely with the theoretically calculated hydrodynamic collision rates, indicating that, in this system, every collision results in capture and retention of a particle.

Jan 1, 1976

By Kenneth P. Katen

Though the use of continuous mining machines consolidated the operations of cutting, drilling, blasting, and loading in one machine that would theoretically provide uninterrupted production, it was soon realized that the face haulage and roof support operations remained as major impediments to continuous production. The ability to provide not only continuous cutting and loading, but also continuous haulage and roof support (see Fig. I), was the basis for the introduction of mechanized longwall systems in this country from Europe in 1951. The early systems employed friction props for roof support, but were to become obsolete shortly after introduction of the first hydraulically powered, self-advancing supports in 1960. Since then, use of the longwall technique has grown to the point where it is currently providing more than 5% of the annual output of underground coal mines in the United States. The shortwall system had its origin in Australia, but was first introduced into this country in 1962 following the development of powered roof supports. It, too, provides for continuous cutting, loading, and roof support (see Fig. 2), but has not experienced the widespread popularity of longwall due to its inherent inability to easily provide for continuous haulage. While there are in the neighborhood of 100 longwall systems currently in operation in this country, there are only a handful of short- wall operations providing production of slightly more than 907 184.7 t/a (1,000,000 stpy) Both of these systems provide uninterrupted roof support for face operations by means of hydraulically powered steel roof supports. In each case, the coal removal consists of open-end cuts made from the narrow end of a large rectangular pillar (panel) which has been blocked out by continuous miners developing entries around its perimeter. However, this is the extent of the similarities between the two systems. It is hoped [ ] that the information presented in this chapter will enable the reader to better understand the two mechanical systems and the mining concepts involved in their employment.

Jan 1, 1981

By Hans-Christian Kurzweil, Klaus Mussger

CERN, the European Laboratory for Particle Physics, are upgrading their existing particle accelerator for the next generation of experiments and have three major packages of underground construction work in progress. Each package involves the construction of shafts, cavern, tunnels and surface buildings. This paper gives an overview of CERN, the LHC Project and a more detailed discussion of design process, design review and construction works of Experimental Point 5. The LHC works at Point 5 include two large shafts, two major parallel caverns with a total span of 50 m, which are separated by a 7 m wide and 28 m high concrete pillar, and a system of secondary tunnels and caverns. The overburden ground consists of around 50 m of water bearing moraine (silty, clayey gravels and sands) overlying 20 mof molasse, which consists of horizontally bedded marls and sandstones. The shaft shave been constructed with ground freezing, primary concrete lining, membrane and secondary slip formed concrete lining. The concrete pillar was then excavated and concreted in advance of excavation of the two caverns. Cavern construction includes primary support of shotcrete lining and rock bolts, followed by waterproof membrane and primary support of shotcrete lining and rock bolts, followed by water proof membrane and insitu concrete secondary lining.

Jan 1, 2003