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The sixth Annual RMCMI Mine Rescue Evaluation was held during the 1997 Institute convention at Sheraton Steamboat Resort, Colorado. The Mine Rescue committee, co-chaired by Becki Boam and Gary Cook, is one of 18 committees of the Institute. In 1997 the largest number of teams participated in the program. There were nine: BHP Minerals - La Plata Mine, BHP Minerals - Navajo Coal Co., BHP Minerals - San Juan Coal Co., Bridger Coal Co., The Coteau Properties Co., General Chemical Co., The Sabine Mining Co., Solvay Minerals and Western Energy Co. Professional evaluators who provided challenging scenarios for the 80 participants were Jack Knight of Milton, Florida; Wilson Begay, Chris Saxon, and Gaylon Yazzie all of Western States Security; Mary Bailey, Bailey Associates; Tom Bass, California Department of Corrections; and Art Saenz, BDC. Seven members made up each team plus one or more trainers and represented the states of Montana, New Mexico, North Dakota, Texas and Wyoming. Ten different scenarios were presented during the two day evaluation. Each team was given the pertinent information to solve the problem as they assembled at the site. Mine Rescue families and friends participated as victims providing realistic scenarios to simulate the stress of an actual rescue incident. Each team was unaware of the circumstances until arriving at the various scenes in and around the Sheraton resort. [ ] These teams are providers of prompt rescue and medical care for accident victims at their respective properties. The members act with immediate and professional knowledge to save lives and prevent further injuries. Sponsors who contributed financially to the 1997 program are: Argo Industrial, Antelope Construction, Fisher Safety Supply, Flanders Electric Motor Service, Inc; Intermountain Electronics, Inc.; King Energy Services, Inc.; Rocky Mountain Electric Motors, LS.; TerraMatrix and Triune Inc. On Saturday evening, June 28, a reception was held for all mine rescue participants and spouses who had advance registered for this social event. The RMCMI Board of Directors was invited to attend and meet with the teams. As convention attendees, all mine rescue participants and registered families attended the Monday night country western reception and Bar-B-Q. This was followed by an adult western melodrama. [ ] Glass awards with the RMCMI logo and a Mine Rescue figure were presented at the Tuesday Mine Rescue buffet breakfast to all nine teams, each of which had achieved proficiency at level 3. Captains of the teams pictured below are (from left standing): Ron Neff, BHP-San Juan; Ted Laughline, Bridger, Terry Davis, Coteau; Jim Knutson, General Chemical (from left kneeling): Dan Allerdings, Rosebud; Ron Miller, BHP-Navajo; Jonathan Sorrell, BHP-La Plata and Ray Blaisdell, Solvay. Gary Cook is to be commended for his solo last minute supervision of the Mine Rescue program, due to Becki Beam's unavoidable absence. The teams look forward to the 1998 convention at Snowmass Village Resort, Colorado Thursday and Friday, June 25 and 26.

Jan 1, 1997

By James A. Finch

The Gaudin lecture is devoted to fundamentals. Given my involvement with column flotation over the last 20 years, this is my topic. I have tried to identify spinoff basic research and provide a personal list of favorites. Two are selected for discussion here. They are single bubble rise and bubble surface area flux. The rationale for such work, as well as some of the findings, are reviewed. Support for fundamental work seems as volatile as the economy (and the link is probably not coincidental). I hope some utility to the minerals industry is evident in the text. Column flotation in its current form originated in the early 1960s. The method was invented by Boutin, patented by Boutin and Tremblay and pursued doggedly by Wheeler. Their aim was to overcome the problem of mechanical entrainment of fine particles in the water carried by the bubbles, which they were convinced contributed to lowering flotation concentrate grades (Wheeler, 1988; Finch and Dobby, 1990). The solution was a combination of columnar geometry, the addition of wash water into a deep froth and the maintenance of an excess of water to the tailings, as compared to the feed (a so-called positive bias). Success at Les Mines Gaspe, Quebec, on cleaning Mo in the early 1980s signaled the start of industrial acceptance, making the column one of the flotation machines of choice today. Over the next 20 years, column applications mushroomed to cover virtually all mineral commodities, as well as nonmineral applications such as soil decontamination, deoiling of water and deinking of recycled paper. In the wake, research groups are continuing to probe the fundamentals, conferences and workshops have been transferring the technology and specialist companies have emerged to service the demand. Innovations were triggered as problems arose (for instance, in gas injection systems) and novel flotation cells, much in vogue in the 1990s, had the door opened. Mechanical cell manufacturers have not been idle - there is nothing like competition to provoke a fresh look at an established business. Flotation-cell technology has probably not seen so much activity since the patent rush in the early days of flotation, which occurred around the turn of the century. For an industry often considered reluctant to risk innovation, this is not a bad record. A good idea will find a place, but patience (not always an innovators strong suit) and careful preparation are required. Two books (Finch and Dobby, 1990; Rubenstein, 1996), three symposia (Sastry, 1988; Agar and Huls, 1991; Gomez and Finch, 1996), and a series of reviews (Dobby and Finch, 1991; Finch and Dobby, 1991; Finch, 1995; Finch et al., 1995) document the period. Like many good ideas, column flotation has been overexposed, and there have been disappointments. In a recent example, columns performing scavenging duty were replaced by mechanical cells (Chong et al., 1998). The further applications stray from the original - to

Jan 1, 1999

By Donald W. Gentry

Introduction The mining industry is perhaps best characterized by the numerous and abnormally high risks associated with the business of mining and by its most basic assets - ore deposits, people and technology. At the most fundamental level, it is the quality and effective utilization of these basic assets that determine a mining company's ability to compete efficiently in the international market place. The gold industry has received much attention in recent years and especially in recent months, for good reason. This commodity serves as an excellent platform for the subsequent discussion of these three basic assets and their role in mining's future. Facets of the gold industry The fate of this noble metal in recent times illustrates some of the various risks associated with the mining industry and the importance of high-quality assets, whether they be ore deposits, people or technologies. The following comments pertaining to the gold industry help place proper focus on subsequent discussions. All monetary amounts given are in US dollars. Throughout 1997, falling gold prices broke record after record: first hitting three-year lows, then a 12-year low in July and finally an 18-year low at year's end. From Jan. 1 through Dec. 31, 1997, the price of gold fell by more than $2.57/g ($80/oz), or some 22%. The decline in gold-mining profitability and stock prices was even more dramatic. At the beginning of 1997, the 20 largest gold producers in North America had a market capitalization of approximately $44.5 billion. At year's end, this market cap had fallen to $26.2 billion, a reduction of 41%. The total market cap of all the world's gold companies fell from $71 billion to $46 billion, a 35% drop (Serwer, 1998). Analyses suggest that, at a spot gold price of $9.65/g ($300/oz), only one, or possibly two, North American gold-producing companies can make money when break-even or "total costs of production" are considered. While strong hedge positions mitigate this situation in the short term, clearly, this is an industry in desperate straits. For example, write-downs for North American producers in 1997 were approximately $2.5 billion. Speculative short positions in 1997 were near historical record highs and generally exceeded long positions by factors of 9:1 or 10:1. Much of this is driven by some US commercial banks, hedge fund managers and commodity speculators who can significantly move gold prices sharply over short periods of time by selling gold they do not own in the expectation they can buy it back at a lower price before they have to deliver. These signifcant short positions are likely to continue as long as central banks are willing to sell or loan gold to financial institutions that in turn make the gold available to speculators who hope to capitalize on price fluctuations. The Far East accounts for approximately 26% of the annual demand for gold. Including India, the region accounts for 43% of total demand. More than 85% of the physical demand for gold is for investment jewelry in Asia and the Middle East. This demand is extraordinarily price sensitive. The fairly recent turmoil in Asian markets and economies, combined with currency devaluations throughout the region, have made gold more expensive (30% to 50% in local currencies) for those peoples most likely to treat gold as a safe investment haven. Higher interest rates also have reduced the amount of money they have to spend on consumer goods such as jewelry. All of these recent Asian events are deflationary in nature. Deflation, if coincident with rising unemployment, could result in significant dishoarding of gold. There is one key fact to remember when analyzing

Jan 1, 1999

[Participating Scholarship Colleges and Universities 138 AmerCable 130 Andalex Resources, Inc 82 Behre Dolbear & Company, Inc 83 Commercial Testing & Engineering Company 86 Continental Conveyor & Equipment Co 87 Crane & Hoist Sales Inc 12 Crested Butte Mountain Resort 88 Dakota Coal Company 89 Empire Machinery Company 90 Energy West Mining Company 91 GH Hensley Industries 92, 93 Hitachi Construction Machinery (America) Corp 96 Ingersoll-Rand Company 131]

Jan 1, 1998

The seventh Annual RMCMI Mine Rescue Evaluation was held during the 1998 Institute convention at the Silvertree Hotel, in Snowmass Village, Colorado. The Mine Rescue committee, co-chaired by Becki Boam and Elliott Tsosie, is one of 18 committees of the Institute. In 1998 a record number of 10 teams participated in the program. The teams were from the four western states of Montana, New Mexico, Texas and Wyoming and were comprised of about eight members each. Teams participating were BHP-La Plata Mine, BHP-Navajo Mine, BHP-San Juan Mine, all from Farmington, New Mexico; Bridger Coal Company, Rock Springs, Wyoming; General Chemical, Green River, Wyoming; Jacobs Ranch Mine, Gillette, Wyoming; Powder River Coal Company-North Antelope/Rochelle, Gillette, Wyoming; Sabine Mining, Hallsville, Texas; Solvay Minerals, Green River Wyoming, and Western Energy-Colstrip, Montana. The professional evaluators provided challenging scenarios for over 90 participants and many observers. The evaluators were: Art Saenz and Tom Bass of Western Environmental Associates, Keith Mitchell and Jim Jennings of Emergency Services Detail; Mary Bailey of Mary Bailey Associates; and John Peleaux of Innovative Access. Teams are not given advance warning of what the problem will entail. They are provided the necessary details when they arrive at the scenario location and work to resolve the problem in an effective and efficient manner. [ ] Seven participants made up each team with an . eighth member as an alternate. Team trainers and other mine personnel traveled with the team from scenario to scenario providing support and encouragement. The teams were presented with four scenarios each day, involving High Angle Rescue, Low Angle Rescue/Medical, Hazmat, and Confined Space. All of the victims, except for one, were provided through the cooperative efforts of the Snowmass Fire Department, who also assisted with providing several evaluators. Snowmass Fire Department is to be commended for providing over 20 victims/evaluators each day to facilitate the evaluations. Training sessions were held Friday afternoon and Saturday evening to help the teams prepare for the scenarios. A swap meet was held Friday evening for teams to trade hats, shirts, belt buckles, stickers, etc. All mine rescue participants and spouses and registered families attended the Bar-B-Q on Sunday evening followed by an adult dance. [ ] Front row: Ray Blaisdell, Solvay; Gary Rasmussen, General Chemical; Spencer Thompson, Sabine; Jack Ervin, Western Energy. Back Row: Ken Kellywood, BHP Navajo; Jonathan Sorrell, BHP LaPlata; Elton Stanton, Jacobs Ranch; Travis Roy, Powder River Coal; Ron Neff, BHP San Juan; Steve Whaley, Bridger. Sponsors who contributed to the 1998 program financially were: Blue Mountain Energy, (Deserado Mine); Flanders Electric Motor Service, Inc.; Rocky Mountain Electric Motors, L.S.; and Western Environmental Associates. Glass trophy cups, with an etching of a Mine Rescue figure and the RMCMI Logo on cherry wood bases, were presented to the 10 team captains at the Monday Mine Rescue Awards Breakfast. Eight of the ten teams had a proficiency level of 3 and 2 teams achieved a proficiency level of 2.

Jan 1, 1998

The eighth annual RMCMI Mine Rescue Evaluation was held during the 1999 Institute convention at the Crested Butte Marriott Resort, Colorado. [ ] Elliott Tsosie, Mary Rowell, Janna Aune, Guy Horton, Art Saenz and Bill Balaz were pleased with the 1999 Mine Rescue Program, The Mine Rescue committee is but one of 17 volunteer committees; this one co-chaired by Bill Balaz, Elliott Tsosie and Janna Aune. There were three evaluators, Art Saenz, Western Environmental; Mary Rowell, ProCare and Guy Horton, Horton Rope Rescue. Nine teams participated and brought 89 participants, 26 spouses, nine children and five teens. The teams were BHP LaPlata, BHP Navajo, BHP San Juan, all from Farmington, NM; Bridger Coal Co., Rock Springs, WY; The Coteau Properties Co., Beulah, ND; Northwestern Resources, Jewett, TX; Powder River Coal Co., Gillette, WY; Solvay Minerals, Green River, WY and Western Energy Co., Colstrip, MT. To observe were members from Centralia Mining Co., Centralia, WA. [ ] Evaluators: Mary Rowell, Guy Horton &Art Saenz The three professional evaluators provided challenging scenarios for the Mine Rescue participants on the grounds of the resort property. Some attending convention were alarmed to see stretchers with "victims" and phoned the hotel switchboard to report the catastrophe. Team members had no prior knowledge of what the scenarios might be and derails were provided only as they arrived at the scenario location, with one exception. Seven to ten or more articipants make up each team. Some teams also ring an alternate and team trainer. For identification purposes, the "victims" wore white shirts emblazoned both front and back with a red VICTIM designation. There was a staged demonstration by three response teams who had not previously worked together. This was enacted on the convention floor following a Technical Session meeting attended by about 200 members. Three response teams from BHP's Navajo and San Juan Mines together with Coteau Properties' Freedom Mine provided a demonstration of their response skills. For never having worked together before, they presented a very professional enactment. This is described at length in the Welcome Session copy. Training sessions were held Saturday and Sunday to enable the teams to prepare for the scenarios. A swap meet was Saturday evening for teams to swap hats, shirts, belt buckles, stickers etc. Each participant received a royal blue golf shirt and ivory cap with royal blue bill. Culmination of the Mine Rescue program was a Tuesday morning Awards breakfast when teams were presented with jade acrylic plaques. [ ] Teams participating in the Mine Rescue Evaluation received trophies on Tuesday morning. The captains above represent BHP-La Plata, BHP-Navajo, BHP¬San Juan, Bridger Coal Co., The Coteau Properties Co., Powder River Coal Co., Solvay Minerals, and Western Energy Co. Sponsors who contributed financially to the 1999 Mine Rescue program were Balaz & Associates, CMC, Civil Constructors, Colstrip Electric, Farmington Fire Equipment & Safety, Fisher Safety, Flanders Ellctric Motor Service, Magnum Metals, Richard Palmtag, Rocky Mountain Electric Motors, Sedona Consulting and Western Water Consultants. [ ] Evaluator Art Saenz likes to have the upper hand and will take whatever steps necessary to get it.

Jan 1, 1999

Jan 1, 1999

[Scott Aberle Western Energy Co POB 99 Colstrip, MT 59323-0099 Randy L. Acre Joy Mining Machinery 2569 Silver Oak Ct. Grand Junction, CO 81505 Brian L. Acton Oxbow Carbon & Minerals Inc 1601 Forum Pl-#P2 West Palm Beach, FL 33401 Laine W. Adair Genwal Resources Inc POB 1420 Huntington, UT 84528-1420 Thomas D. Aderman The North American Coal Corp 14785 Preston Rd #1100 Dallas, TX 75240-7891]

Jan 1, 2000

By G. Swan, E. Nordlund, P. Zhang

"SynopsisThe most widely used support design damage criterion for rockburst-prone mines is based upon kinetic energy, which is proportional to the square of the ejection velocity and is commonly expressed in terms of peak particle velocity (PPV). Field monitoring and back-analyses have shown that ejection velocities of the order of 10 m/s and higher can result from seismic events of moderate magnitude. Such velocities are much higher than those predicted using PPV obtained from scaling laws. It has also been found that the peak ground motion (i.e. PPV) on the surface of an excavation is preferentially amplified (by four- to tenfold) compared to the motion in solid rock at a similar distance from the source. However, the wave propagation and interaction processes involved within the fractured rock in generating high ground motion are very complex and are not well understood at this time.In this paper, velocity amplification was investigated by modelling the dynamic interaction between fractured rock and a free surface using a 2D discontinuum-based numerical program, UDEC (Universal Distinct Element Code). A 1D model with a fractured zone was used to represent the fractured rock. Velocity amplification, quantified by PPV, predicted at the free end of the model was 2.0–3.6 times higher than the input velocity. It was found that the wave frequency, fracture stiffness, fracture spacing, and thickness of fractured zone are the main factors that affect the velocity amplification. The results have proved that the interaction of the seismic wave and multiple fractures near the free surface strongly influences the ground motion.IntroductionSince mining-induced seismicity is almost inevitable in deep mines, ground support is generally employed to mitigate the risk of seismically-induced damage. The most widely used support design criterion for seismicallyprone mines is one that seeks to maximize the absorption of the kinetic energy (plus potential energy if a gravity component is considered) of key rock blocks. Based on this criterion, design methods for rock support were first proposed by Wagner (1984) in South Africa and later improved, among others, by Roberts and Brummer (1988) and Kaiser et al. (1996)."

Jan 1, 2015

By Claudio Cesar da Costar

O Alto Forno 1 da ArcelorMittal Tubarão, operou entre 30 de novembro de 1983 e 18 de abril de 2012, produzindo 93.915 Mt. Durante esta campanha, inúmeras melhorias foram implementadas para aumentar sua longevidade mantendo o volume e custo de produção. O Alto Forno 1 da AMT é reconhecido como recordista tanto em volume de produção quanto em tempo de operação para uma única campanha. Durante sua reforma, foram empregadas as técnicas de reforma em grandes blocos, as quais foram trocados todo o cadinho, corpo e topo do Alto Forno, trazendo recursos tecnológicos possibilitando obter melhores resultados durante a segunda campanha. Após a reforma, o Alto Forno 1 continua apresentando bons resultados em termos de produtividade, consumo de combustíveis e índices de trabalho, colocando-o entre um dos Altos Fornos com melhores resultados do grupo ArcelorMittal.

Aug 16, 2017

By John Beaumont

The Plate-Steckel mill combines the asset utilization of the strip rolling process with the grade and width range of the reversing plate mill, delivering a broad range of steel products at low cost. Among rolling mill types, plate mills are distinctive in the way that they exploit the metallurgical attributes of their product. The downside of this flexibility, though, is a low level of asset utilization. The Plate-Steckel mill was originally developed to combine the utilization of the strip mill and the width of the plate mill. The Plate-Steckel mill is now setting new benchmarks in accessible grades and applications, whilst pushing the width boundaries of the process. Long experience in the Steckel process control and coiler furnace design is coupled with caster and plate mill expertise to deliver high level of performance in this increasingly important plate and coil rolling technique. Several new design features have been incorporated and the vertical integration of mechanics with process models is the key for better product quality and flexibility at these plants. The use of fully automatic thermo-mechanical rolling using the latest physical models and intelligent sequencing strategies achieves the optimum grain refinement and thus improves mechanical properties. The novel profile and flatness strategy relies on comprehensive physical models and makes use of SmartCrown® as a powerful actuator, enabling large reductions to be taken without risking poor flatness. Throughout the rolling and cooling stages of processing, accurate calculation of the thermal-mechanical state of the product is performed by the temperature monitor. This enables tighter control of the final plate mechanical properties by providing an insight into the plate evolution during the thermo-mechanical processing. Advanced pacing functionalities provide an optimized mill throughput, utilizing new cooling bed charging strategies. Considering the rolling process, process automation applies state-of-the-art model calculations to achieve saleable coil/plate target dimensions even in non steady state rolling conditions.

Aug 16, 2017

By Bengt H. Fellenius

Session 2, Deep Foundation without Soil Excavation, has attracted no fewer than 22 papers dealing with subjects from soil improvement by grouting, injection, and deep mixing techniques through vibroflotation and special piles, including aspects pertaining to conventional driven and bored piles. In the short time available, it is not possible to both do justice to the papers and provide a critical review of the state-of-the-art. Instead, to meet the objective of making the next half hour worthwhile to the audience, I have chosen to comment on a few special points brought forward in the papers and thereafter to discuss more in detail a couple of aspects I have deemed to be of general interest. Four papers deal with jet-grouting, injection, and deep mixing techniques: DOMSKI, J. J. Reinforcement of subsoil under the foundations of historical buildings in Cracow using deep injection technique. RESTELLI, A. B, BERTERO, M., and LODIGIANI, E. Deep mixing technology to improve the bearing capacity of a very soft clayey soil under an earth embankment.

Jan 1, 1994

By Kostas Kaklis, Zach Agioutantis, Robin Flattery

Pillars are used as the primary support structures for underground mining to maintain stability by supporting the over laying strata. In the case of horizontal seams, the pillars are typically subjected to axial loading due to the weight of the overburden and/or abutment stresses, while in the case of inclined seams they are subjected to oblique loading due to both the vertical and horizontal in-situ stress.

By Richard A. Bideaux

With both unit costs per meter and average depth of drilling constantly increasing, there is a strong incentive to maximize the information acquired from drill holes, and then to make this information accessible to the geological staff. The larger the drilling project, the more advantageous computerization of data is over manual methods. The conversion to computer-readable form and the verification of large amounts of drill-hole data can be a substantial data processing task, but once accomplished, the benefits in increased accuracy and speed of interpretation will compensate for the time and effort spent in the work. For an exploration project progressing towards a preliminary feasibility study, about half of both the time and costs for all computer work of the entire feasibility study are devoted to drill-hole data base organization, and maintenance. Once drill-hole results are quantified and verified to be correct, they are immediately accessible and are not subject to further transcription or reinterpretation of errors. To obtain maximum benefits from computer utilization in this area, the drill-hole data base should be set up along with availability of the first data. For some companies, this may initially comprise a large number of purely speculative drill holes on a spacing of perhaps 1 or 2 km. Although few of these drill holes may encounter economic material, thought should be given, at this time, to the variables which will be logged when such material is found. In this way, it should be possible to set up a consistent format into which all future drill-hole information will readily be accommodated. This format may even be carried over into the data base requirements for an operating property.

Jan 1, 1979

By F. L. Wilke

Underground mining is a very complicated and complex industrial activity. The uncertain and, in most cases, the incomplete knowledge of the geological and mineralogical nature of the deposits can cause unforeseen difficulties. For a safe and uninterrupted operation, in addition to good planning and scheduling, reliable and up-to-date monitoring and control of all processes and conditions become necessary. Today, this is even more important in view of increasingly difficult working conditions, poorer grades, and more complex and expensive machinery. In short, large capital investment and higher risk of financial losses are involved in modern-day mining operations. Monitoring and control of the underground mining process has become a very complex and difficult task in itself. Many different systems are available, and the correct choice .is of utmost importance from both the economic and safety points of view. This chapter will deal with aspects of underground production monitoring and control. There are, however, many other areas of equal importance which are covered in an excellent manner in a hand- book by Olaf (1976) on monitoring and control of underground operations.

Jan 1, 1979

By James N. Grassby

Metal production has traditionally been a cyclical industry. 1977 in the base metals industry has highlighted that fact with a steady decline in the market place for base metals. Corporate aggregate planning is based on good forecasting and when changing conditions make that forecasting inaccurate, alternate analysis of schedules must be accomplished quickly. The computer is the only medium powerful enough to answer management's questions within an acceptable time frame. Worldwide communications networks now make it possible for the many multinational mining companies to arrive at coordinated corporate production plans based on similar basic data from several producing divisions. The Ontario Div. of Inco Metals Co., a unit of Inco Ltd., encompassed during 1977 14 producing mines, 2 nonproducing mines, 1 nonproducing open pit, 5 flotation mills, I smelter, 2 nickel refineries, 1 copper refinery, and an iron ore recovery plant. Several new mines are under development. Mine production approximates 63 500 tpd (70,000 stpd) from some 1000 workplaces. The need for longrange mine planning and scheduling is obvious and until recently has been satisfied by manual methods. However, while manual methods are often quite practical for a small number of mines, or for mines with relatively short lives, or for mines with only one mining method, the situation in the Ontario Div. is too complex and long-term to allow effective, timely planning by such methods. In 1967, a year after the first computer was installed in the division, work was begun on the computerization of the more than 30,000 borehole logs kept in the mines exploration files with a view to speeding up the assessment of mineral resources. Also in 1967 one of the first substantial systems developed on the main business systems computer was the monthly scheduling of development and production for all mines. This system encompassed tons productions per workplace, feet development per workplace, auxiliary and service activities and the requisite labor for each of these. These two dates are mentioned to show that concurrently with the acquisition of computers in the division there was an early understanding of the importance of automating mine scheduling and planning and of the potential for effective and useful computerization of such activities. In 1970, a pilot program was developed in one of the mines containing a large number of workplaces (350) to schedule the production on a network basis. Varying degrees of interest were shown by the individual mine engineers based on the complexity of the production planning problem at each mine. In an evolutionary process, mines were added to the system as its value became obvious in terms of time saving, flexibility, and accuracy. In 1975, the central mine engineering department decided that the system should be extended to all mines so that a complete division-wide long-range scheduling system would be available upon which to base development and production planning. This system would use basic ore data, allow the addition of scheduling commands, and calculate a schedule for the life of the mine. Many reports could be produced for each mine and all-mine summaries would also be available. The significance of the system can be stated in one phrase-speed, accuracy, and flexibility. Whereas in the past a long-range all mines schedule might have been done once a year, taking from two to three months, now it can be done in a day. The chief mines engineer can incorporate changes in input data and external constraints and call for a "new look" at the long-range schedule to assist him and mines production management in their decision-making processes. Using previous manual methods this could not be done quickly enough to be useful.

Jan 1, 1979

By David B. Dill, Edgar R. Lea

The zinc deposits of the Balmat-Edwards Division of the St. Joseph Lead Company in northern New York State provide some 10 per cent of the domestic zinc produced annually within the United States. These complex ore deposits are contained within marbles of the Precambrian Grenville series, in a repetitive sequence of dolomites and silicated units. The Balmat ore bodies are localized at various intervals throughout some 1800 feet of the stratigraphic column on the northwest side of a band of gneiss that has continuity to the Edwards area, some 10 miles to the northeast. The Edwards ore bodies are located to the southeast of this gneiss. The marble formations are thought to have included repetitive intervals of marine sedimentation that provided mineralized source "beds" and were subsequently folded, flooded, and injected with melts at great depth and were sheared, recrystallized, and reconstituted. Detailed structural and stratigraphic studies throughout the northwestern Adirondacks, in the Balmat-Edwards district, and at each mine in particular indicate the close dependence of the ore deposits on the enveloping structure whether it be local, district-wide, or regional in scope. Primary folding has developed a northeast regional trend with northwest dips. Secondary folding has been developed by an almost horizontal northeast-southwest-oriented shear couple in the plane of the regional trend. The secondary folding has produced crossfolds that intersect the regional northeast trend and plunge north to northwest at various angles. The ore bodies are found within certain stratigraphic horizons where repeated alternation of competent and incompetent beds encouraged unusually complex folding. Analysis of individual mine structures indicates that the location of each deposit is controlled by structural crossing of primary and secondary folding. The ore bodies, which are tabular, lenticular, or pod-like in form, have features that suggest parallelism to true bedding or modified flow banding, developed by northeast-southwest shearing stresses related to the development of the crossfolds. The ore deposits in general follow both structural and recrystallization trends within the wall rocks. Mobilization of the pre-metamorphic ore minerals is believed to have involved a combination of plastic flow under stress and solution of the sphalerite, minor galena, and pyrite. The ore fluids are thought to have been guided by secondary shearing and microbrecciation into structurally prepared areas where reprecipitation took place. The presumed premetamorphic mineralization now exhibits epigenetic high-temperature features related to late-stage metamorphism.

Jan 1, 1968

By P. Rice, A. Photolo, A. C. Barnard

Introduction -Sampling Tool Project (STP) -History -Results to date -Costs -Questions

Jan 1, 2005

By Richard C. Fox

"Why geophysics? We will have to drill anyway." Reliance on geophysical methods for detailed target appraisals will increase as direct surface evidence becomes more subtle. This will create a need for more effective and efficient geo- physical programs. Numerous computer-based techniques that deal with a broad range of geophysical problems are described in the literature. The purpose of this chapter is to provide a framework for the systematic application of these techniques to effect an overall optimization of the geophysical appraisal. The concepts described are not technique specific, but should serve as a guide for increasing the effectiveness and efficiency of any geophysical program. Fig. 1 shows a generalized flow chart of the major aspects of the program described. The three main subdivisions of a 'geophysical program are discussed: (1) survey design, (2) data processing, and (3) data interpretation. Detailed flow charts, outlining the goals, the requirements for meeting the goals, and the steps followed within each subdivision are presented at the beginning of each section. The objectives and type problems of each subdivision are defined, followed by a description of applicable computer methods. . References are cited that give a general cross section of computer techniques available in the literature, and examples are given in each subdivision to demonstrate basic concepts and the use. of computers in solving the type problems.

Jan 1, 1979

Sampling In The Coal Industry Exploration, Mine, Met and Environmental Sampling EMMES 2005 3, 4 November 2005

Jan 1, 2005