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By Daniel Hauer

Blocking. (5) The “blocking” of boulders is a much cheaper way of breaking them up than “mud capping.” It should always be used in preference to that method except when too much time will be consumed by a crew of men waiting for the drilling to be done, as shown in example of cost No. 1, as given under “mud capping.” Under such circumstances the time consumed would be a greater cost to the contractor than the extra amount of dynamite. Then, too, on large thin boulders to drill one hole would result only in breaking the stone into such pieces as would again have to be broken; and the many holes might equal the cost of extra dynamite. Under such circumstances if method (6) cannot be used, “mud capping” will have to be resorted to, to do the work economically.

Jan 1, 2006

By Roberto Folchi, Hans Wallin

Lake Mead, the largest man-made reservoir in the United States, is located about 30 miles southeast of Las Vegas, Nevada. For the construction of Lake Mead third water intake, which is entirely placed underground, an underwater excavation was needed at a depth of 100 m (330 ft): a large surface had to be deepened by 20 m (66 ft) in basalt.

Jan 1, 2012

By Colwell J. B, Constantine A. E

A unique, regional grid of deep (12 - 14 second record length), seismic reflection and refraction data has been recorded by the Australian Bureau of Mineral Resources (BMR) across the offshore Gippsland Basin and parts of the adjacent Bass Basin, in southeastern Australia. These data have been combined with onshore mapping to produce a new model for the development of the Gippsland and adjacent Bass Strait basins. Overall, the Gippsland Basin contains up to 12 - 14 km of sediment in an ESE-trending depocentre bounded on its north and northwestern margins by a detachment ramp, and on its southern side by a relatively linear, listric fault system. The basin, together with the adjacent Bass and Otway Basins, appears to have formed as part of a linked, largely- strike-slip to 'transtensional' system, which started to extend through Bass Strait, probably during the latest Jurassic. Each of the basins developed by movement on a common detachment or detachment complex, which produced headwall extension at their western ends, in the areas now occupied by the Strzelecki Ranges, Otway Ranges - Torquay Sub-basin, and Robe Trough. Adjustments and reactivation from the mid Cretaceous of several postulated microplates in the region, largely in response to Tasman Basin rifting, gave rise to the wrench-related and compressional structures which form the major petroleum targets in the Gippsland Basin. However, the same process formed largely extensional stuctures in the Bass Basin. Our interpretation of the tectonic history of the Gippsland Basin leads us to the conclusion that there may have been several phases of petroleum generation and migration, and that potential petroleum traps appear to exist in the deeper section, in structures sometimes not reflected at the top or near-top Latrobe Group levels.

Jan 1, 1992

By Terry S. Cory

This report is a comprehensive summary of the results of the propagation measurements program conducted for the US Bureau of Mines under Contract H0366028. Data was gathered in the MF frequency range from a cross sample of six mines representative of the industry having typical wireless requirements. From the raw data which was gathered, a logical method of data reduction is presented which culminates in a set of average attenuation characteristics for all mines visited. These characteristics define a typical MF wireless system when the communication range requirements are known. Direct through-the-earth propagation and the range enhancement mechanism due to coupling on and off conductors are evaluated and related to the planning of a typical wireless MF communications system.

Jan 1, 1977

Three large deposits of good quality lignite were located and delineated in the Central Otago region between October 1978 and July 1979. The program was initiated and funded by Mines Division of the Ministry of Energy as part of the national Coal Resource Survey. The exploration work was carried out by Lime and Marble Limited on a contract basis (Bowman, 1980). The three deposits were all potentially mineable by open cast methods and possessed combined indicated and, inferred reserves in the order of 1000 x 106 tonnes. They ranked with the previously discovered Eastern Southland 1ignites and as such constituted an important national energy resource. Fifteen months later a second more detailed investigation of similar duration was undertaken by the Liquid Fuels Trust Board (LFTB). The objective was to upgrade and refine the geological data base of all of the nine South Island 1ignite deposits in order to make preliminary economic assessments of their potential. Again Lime and Marble Limited acted as the exploration operator (Bowman, 1981a, 1981b, 1981c).

Jan 1, 1983

By Brian Fulcher

In April 1997, Kiewit/Parsons Brinckerhoff (K/PB) completed the 7,600-m (25,000-ft) primary access tunnel for the Yucca Mountain, NV proposed high-level nuclear waste site. K/PB then began boring an exploratory east-west cross drift tunnel at the site. The 2,681-m (8,796-linear ft)East-West Cross Drift Tunnel was excavated through volcanic tuffs having zones of incompetent rock using a rebuilt Robbins 5-m (16.4-ft)hard-rock tunnel boring machine(TBM) with a special arrangement of supporting equipment. This portion of the Yucca Mountain project was completed in eight months.

Jan 1, 2000

It is a great honour to be privileged to address The Institute for a second time as President and I appreciate it more than I can say. Eight years ago in Hobart I tried to cover the development of the mineral industry in Tasmania. That was a general subject. Tonight I want to be more specific - I propose to talk to you about rutile.The choice of subject for a Presidential Address is never easy. One is addressing an informed audience and the best one can do is to try to crystallize a particular subject and to present it in a form that willbe of interest to those who listen.I looked carefully at the addresses given by our Presidents over the past seven or eight years. The titles are impressive, the content excellent, and the length, as published, much greater than I had hoped.It is therefore with some trepidation that I have chosen as a subject one only of the three crystal forms of titanium dioxide. This subject is not as limited as may at first appear.There are two aspects with which I can deal - the mineral itself, which has become familiar as the major product of the East Coast beach sand operations, and the lesser-known "synthetic" product, which is the major pigment in almost all the white paints in common use today, and in cosmetics and white-walled tyres and toothpaste, and even the better types of fine papers. The synthetic form of rutile is' the "whitest"of white pigments.

Jan 1, 1966

Paper 1: Risk of gastrointestinal cancers from inhalation and ingestion of asbestos, John F. Gamble Selikoff suggested the hypothesis that asbestos exposure is causally associated with increased risk of gastrointestinal (GI) cancers in an early study of insulation workers. In this paper, John Gamble reports on his extensive review and reanalysis studies that address the relationship between asbestos exposure and GI cancers. The purpose of the review was to evaluate the association between asbestos exposure and risks of stomach, colorectal, colon, and rectal cancers separately. Gamble evaluated exposure?response (E?R) relationships using surrogate exposure methods ??because few individual studies of GI cancer have reported exposure? response analyses.?? The principal asbestos exposure surrogates are: (1) the rate ratio (RR) for lung cancer; and (2) the percent of mesothelioma among exposed workers. Analyzing SMRs for GI cancers from individual studies versus the risk of lung cancer and mesothelioma provides crude estimates of E?Rs for asbestos exposure and GI cancer. Briefly, Gamble justifies the surrogate approach as follows:

Jan 1, 2007

By J. Bruce Clemmer, M. F. Williams, B. H. Clemmons, Carl Rampacek, R. H. Stacy

"INTRODUCTION This report is the first of several dealing with the application of flotation methods for beneficiating the calcareous and siliceous red iron ores and ferruginous sandstones of the Birmingham district. The flotation study was part of a general investigation of the concentratability of various iron ores of Alabama and other Southeastern States undertaken by the Southern Experiment Station of the Bureau of Mines, United States Department of the Interior, in cooperation with the University of Alabama, Tuscaloosa, Ala.Batch testing and pilot-plant flotation testing of the calcareous red ores of the Birmingham district have been in progress for several years, and although some phases of the study are not yet completed, enough data are available to indicate that many of the ores will yield marketable-grade concentrates with good recovery.The first flotation tests on the calcareous red ores employing conventional methods either the iron oxides or the siliceous gangue materials failed to give the desired results. The inferior separations obtained or prohibitive reagent requirements made the methods unattractive. Other more effective flotation methods were sought. A laboratory study of various reagents was undertaken. It resulted in the development of two attractive methods embracing anionic flotation of the activated siliceous gangue from the retarded iron oxides. The methods were similar in that fatty acid or soap-collecting agents were employed in strongly alkaline pulps to float the naturally activated quartz from the iron-ore pulps. The methods differed, however, in the addition agent employed to retard the hematite or hematite and calcite. By proper choice and quantity of the addition agent, the calcite could be floated with the quartz or retarded with the hematite as desired. Ability to recover or reject the calcite gives added flexibility to the separation. Although the methods have their limitations and cannot be considered ""cure-alls,"" they have given encouraging results on a number of calcareous red ores that heretofore proved difficult to concentrate by conventional flotation procedures."

Mar 1, 1945

By Tim Peterson

Factors Controlling Stability Stability of slopes in soft rock, waste dumps or soils is governed by three factors: ?Slope configuration ?Groundwater ?Shear strength

Jan 1, 2004

Heap leaching for the recovery of precious metals is a comparatively new and rapidly expanding technology. The practical aspects of heap leaching are described and environmental and economic implications discussed.

Jan 1, 1984

Les Mines Inmet ? La Division Troilus exploite une mine d?or à ciel ouvert depuis 1996 et produit un concentré de cuivre. La Division Troilus est localisée à 175 KM au nord de la ville de Chibougamau? au 51 parallèle.

Feb 1, 2008

By R. Larry Grayson, Joel R. Warneke

The mining industry has searched for a message that will resonate with the public while focusing on the industry’s positive contributions to society. So far, environmental groups remain unconvinced and the public is still largely uninformed. In the authors’ opinion, a number of recent events and experiences have converged to help shape a more effective public communication on mining’s important role. This article presents a perspective on coal’s role in sustaining society by anchoring the message in a transparent way, including a material flow analysis, that links coal’s impacts across a range of social and environmental aspects. Past and continuing image problems In her 1994 paper, Nancy Bingham, with Caterpillar, outlined what the public thought about mining. Based on extensive interviews, the following results were found: • The public believed mining harms the environment. • The public believed mining harms people in nearby communities. • The public believed mining exploits workers. • The public believed mining has little personal benefit to the individual.

Jan 1, 2006

By S. J. Haynes

"This paper documents the characteristics of the different quartz veins, and their relation to gold, in the turbiditic Meguma domain of eastern Nova Scotia. Eleven different types have been distinguished in the greenschist facies on the basis of form, internal structure, mineralogy, wallrock alteration and crosscutting relationships to each other and to regional structures. Gold is present as rare visible disseminations in host rock slates and in ore-grade, early-formed veins, that pre-date the formation of upright Acadian folds and intrusions of Devonian granitoids. Four vein types pre-date Acadian folding. Five gold-deficient vein types are associated with Acadian folding (syndeformation); whereas two gold-deficient vein types clearly post-date this deformational event: Previously unreported, wall rock alteration is associated with early crosscutting and semiconcordant auriferous veins. In contrast, early stratiform veins are devoid of wallrock alteration. It is suggested that the auriferous vein arrays formed as submarine exhalitive systems over synsedimentary tensional faults and that the Meguma domain may represent the opening of a basin similar to the modernGuaymas rift .IntroductionThe term ""turbidite-hosted gold deposits"" is introduced to distinguish gold deposits contained within a turbiditic sequence of wackes and shales (or their metamorphosed equivalents) from gold deposits in other types of sediments. Usage and justification for the term is similar to ""carbonate-hosted lead-zinc deposits"" or ""volcanogenic massive sulphides"". A range of different characteristics can be present in individual deposits, some of which may be indicative of specific deposit types in the same manner that volcanogenic massive sulphides can be subdivided into ""Cyprus type"", ""Kuroko type"", ""Besshi type"", etc. Historically, gold deposits hosted by turbiditic flysch were an important class of quartz-vein gold mines in the 19th century. They included the goldfields of Victoria, Australia, Otago, New Zealand and Nova Scotia, Canada. Production from most of these fields had ceased by World War II and interest in this type of deposit waned. However, the recent exploration interest in gold has resulted in both re-assessment of the classical mining camps and the discovery that ""turbidite-hosted"" gold deposits are present in many parts of the world.Mapping of the regional geology and gold deposits of the Megumadomain of Nova Scotia was carried out by E.R. Faribault of the Geological Survey of Canada between 1886 and 1939. Faribault produced a comprehensive series of maps and reports for each gold district, a compendium of which was published by Malcolm (1929)."

Jan 1, 1987

By Lucas Lopes da Costa

In this work, a natural foam extracted from the Amazon buriti palm tree is investigated as possible substitute for synthetic foams. The basic physical and mechanical properties of this biofoam were evaluated. Its sponge-like structure was characterized by the amount of pores and morphological aspects. It was found that the buriti biofoam displays a very low density of the order of 0.1 g/cm3 with a relatively good compressive strength. This would be suitable for several engineering applications and as a new material with the potential for replacing currently applied synthetic polymeric foams.

Jan 1, 2010

By Homer S. Frankhouser

Materials may be dredged, processed, stored and loaded for shipment at a single site in water depths ranging from 250 to 1200 ft. Solution mining may also be accomplished in deep sea situations. And, open air subsea mines with direct surface access may be developed and worked under the ocean floor. These concepts for deep sea mining are the results of extensive testing of individual components of the proposed systems by Dravo Ocean Structures, Inc., a subsidiary of Dravo Corp. A basic structure in these systems is the articulated platform. The platform consists of a gravity- type base and a buoyant cylindrical column which is constructed at an onshore location, towed to the offshore site and installed in a matter of days without use of heavy equipment. The base is also buoyant for towing purposes. This allows for gradual flooding to the point of negative buoyancy for positioning and anchoring to the ocean floor.

Jan 1, 1971

By B. Anameric, S. Kawatra

Pig iron nuggets, which have similar chemical and physical properties with blast furnace pig iron, were produced by a single step heat treatment of self reducing – fluxing dried greenballs. During this single step heat treatment the transformation of self reducing fluxing dried greenballs into pig iron nuggets did not take place instantaneously. Rather, it was composed of three transformation stages, (1) transformation of self reducing – fluxing dried greenballs into direct reduced iron (DRI), (2) transformation of DRI into transition direct reduced iron (TDRI), and (3) transformation of TDRI into pig iron nuggets. Thus, the objective of this research was to investigate these transformation mechanisms by analyzing the transformation stage products. The transformation stage products were produced at a constant furnace temperature of 1425°C and various furnace residence times. They were characterized according to their microstructure, microhardness and apparent density. The changes in the product’s physical and chemical properties with furnace residence time were utilized in understanding the transformation behavior, the chemical events that took place and the controlling mechanisms. It was determined that the transformations were dictated by the changes in the slag viscosity and wetting properties, and by carbon diffusion into metallized areas.

Jan 1, 2007

By Pavel Vasak

Microseismic monitoring has become standard practice in the mining industry as a ground control monitoring tool at depth. Translating the information into practical hazard assessment tools for the rock mechanics practitioner is the focus of research jointly conducted at Creighton Mine by INCO Mines Technology Centre (MTC) and the Geomechanics Research Centre (GRC) in Sudbury, Ontario. Rock mass damage mechanisms are typically related to stress and the presence of geological structures. Due to well executed de-stress blasting practices at the mine, stress related problems are minimized. However, structurally related damage mechanisms associated with shear zones, faults and joints pose a substantial hazard. Identifying active structures from the dataset of seismic and microseismic events is generally problematic. We propose a new methodology that uses a combination of spacetime event density, hierarchical clustering and principal component analysis to identify planes of microseismic activity, termed active planes (APs). Once identified, the presence and intersection of active planes can be used to provide a hazard ranking for nearby excavations. The ranking is based on the standard Q rock mass classification system, with emphasis on the joint set number (Jn) and stress reduction factor (SRF) parameters. If the rock is treated as a fractured continuum, then, the Jn indicates the degree of freedom for blocks to move and hence, increased potential hazard. An increased hazard can also result if the APs are larger-scale and discrete (faults) rather than ubiquitous (joints). In this case the SRF is used as a measure of the degree of looseness in the rock mass.

May 1, 2004

By Ian D. Pirie

Presentation outline ?Project location ?Geology ?Resources and reserves ?Results of the FEED study ?Social and environmental considerations ?Project path forward

May 1, 2010

INTRODUCTION ò World coal production, Exporters and Importers òNew Zealand Exports, Markets and Products ò Types of Markets and Price Setting ò Bench Mark Prices and Exchange Rate ò Transport ò International Marketing - Key Factors ò Coal New Zealand , the Challenges

Jan 1, 1996