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By SAHENDRA SINGH, SANJIT KUMAR PAL, DHARMITA HORO

The North Singhbhum Mobile Belt (NSMB) lies between two crustal-scale shear zones, the South Purulia Shear Zone (SPSZ) at the north, and the Singhbhum Shear Zone (SSZ) at the south. The Babaikundi-Birgaon Axis (BBA) is an east-west trending secondary shear zone in the NSMB lying south of SPSZ, which is known for the occurrence of gold along with other sulfide minerals within the quartz reefs. The present study has been carried out at north of Ichadih village, which lies on the BBA. The present study attempts combined electrical resistivity tomography (ERT) and self-potential methods along a profile of 470-m length in the Ichadih area to map the potential mineralized zones. Initially, ERT sections generated by Wenner, Wenner- Schlumberger, dipole-dipole, and joint inversion of the combined array have been analyzed, and results are validated through the analysis of model resolution. A prominent low resistivity (10–100 Ωm) associated with quartz reef/limonitic quartz reef at a depth of approximately 30–85 m, encircled by a high resistive (more than 10,000 Ωm) formation associated with metasedimentary rock, has been delineated using joint inversion of the combined array. Further, analysis of self-potential (SP) anomaly using particle swarm optimization inversion also confirms the prominent low SP anomaly at a depth of 77.3 m, which is analogous to the low resistivity anomaly identified in the joint inversion of the combined geo-electric array. Subsequent analysis of a complex synthetic geo-electrical model analogous to the present field situation proves the efficacy of the joint inversion of combined arrays. As a whole, joint inversion of multi-array data is established as an efficient technique for better subsurface imaging in case of the complex subsurface structure. In-depth analyses confirm the possibility of sulfide mineral-rich deposit (quartz reef/limonitic quartz reef) which requires further geological drilling and lithogeochemical sample analysis, for possible future exploration.

Oct 26, 2020

By Eric Lundgren

The mining paradigm is changing on the continent of Africa. Jessica Kogel?s closing statement from her September 2013 President?s Page (ME, September 2013, pp. 6) has never been more appropriate, ?Africa is shaping up to be the next mining powerhouse, and there is huge opportunity for local communities, national governments and private industry to work together to create a win-win situation for all.? Supporting this notion, attendance at numerous industry conferences around the world demonstrates the shift toward a more sustainable, more environmentally conscious extractive model. But questions remain: How effectively is the industry making this transition, and how willing are companies to learn from the experiences of others? The international development community, as we like to call ourselves, is going through a parallel shift. We are experiencing our own funding crisis; governments are not as flush with resources as they were pre-economic meltdown. But more importantly, after a half century of implementing development programs, we must admit that while some of our programs have been fantastically successful, too many still fail to achieve the goal of poverty alleviation for the world?s poorest. Moving forward, we are forced to recognize that achieving success in scale and sustainability is not always accomplished from our work alone. As the director of international programs for Africare, a nonprofit with more than 40 years of experience implementing community-based development programs in Africa, I can report that our organization is changing the way we think about successful development partnerships. Africare recognizes that for too long the mining sector and nonprofits have been at odds, choosing noncommunication as a ?solution? to the problem. Both sides now recognize that this standoff is outdated, and Africare, specifically, is ready to cross the proverbial line. We see the potential benefits of mining for local communities and, when done responsibly, the opportunity to properly manage Africa?s resource boom as a benefit to all. There are challenges in this conversation. Many mining professionals view nonprofits as whistle-blowers, ready in a pinch to speak to news sources and complain about poor operational standards. Those are advocacy organizations, and while their role is important, they are not the only nonprofits interested in mining operations in developing countries. Organizations like Africare, with decades of experience implementing poverty reduction programs, approach this differently. We know we can work with mining companies to promote economic opportunity in the communities where mining operations are occurring. We recognize that the conversation is difficult, and we are open to discussions about how we can bring our unique experience to bear on the problems faced by mining companies in carrying out their investment programs.

Jan 1, 2014

By John W. Frey

This paper presents one of a series of digests of foreign mining legisla- tion and court decisions which is being prepared in advance of a general report relative to the rights of American citizens to explore for minerals and to own and operate mines in various foreign countries. This interpretation of the laws of Trinidad has been prepared from the best information available in ashington but is released subject to correction and amplification, if necessary, by the proper American diplomatic and consular officers to whom it is being referred through the courtesy of the Department of State.

Sep 1, 1930

By James S. Browning

For the past several years, the Bureau of Mines has conducted laboratory and continuous process development work on weathered mica pegmatites and micaceous schist ores to determine the feasibility of recovering commercial-grade mica concentrates by flotation. The research has resulted in the development of two processes for flotadon of mica: an acid cationic method for recovery of coarse mica, and an alkaline anionic-cationic method for recovery of fine mica. The research indicated that the two processes may be effectively utilized separately or in combination for flotation of mica from weathered pegmatites and micaceous schists. Concentrates containing over 98 percent mica, with recoveries ranging from 77 to 92 percent, were obtained from the pegmatite ores. The micaceous schist ores yielded concentrates containing 95 to 98 percent mica, with recoveries ranging from 70 to 83 percent. Part 1 of this report summarizes the process development work and demonstrates the feasibility of producing commercial- grade mica concentrates. The report also includes details of commercial beneficiation and grinding of .mica.

Jan 1, 1973

By Westwater, J. S.

The Mather mine of The Negaunee Mine Co. embraces nearly all of Sections 1 and 2, T47N, R27W. within the limits of the cities of Negaunee and Ishpeming on the Marquette iron range of Michigan's Upper Peninsula. Operations of the Negaunee Mine Co., the stock of which is jointly owned by Bethlehem Steel Co. and The Cleveland-Cliffs Iron Co., are under the direction of the latter company. The opening of the Mather mine was described by C. W. A1len. Mather "A" shaft was completed to an initial depth of 2352 ft in early 1943. The shaft capacity of over one million tons yearly is in prospect of being realized by orderly development and mining, and sinking of the second or "B" shaft then started in accordance with previous planning. Mather " B, " also a vertical shaft, was designed as a twin to Mather "A" shaft and the sinking technique developed at Mather "A" was utilized in "B" shaft operation.

Jan 1, 1949

By F. Y. Kang

Graphite with layers structure is easily to form graphite intercalation compounds (GICs) by means of intercalation reactions due to the weak cohesion force among carbon layers, van der Waal?s interactions. By controlling the oxidation-intercalation, high quality exfoliated graphite with low residual sulfur content and MClx-GICs (M=Fe, Co, Ni, Cu, Zn) powder for electromagnetic wave absorbing and shielding materials have been invented. The expansion volume of expandable graphite can be larger than 160 mL/g while the residual sulfur content is less than 800 ppm. The MClx-GICs powder can shield infrared ray and laser completely up to 15 min. We have also in-vented exfoliated graphite for heavy oil adsorption and mild-expansion exfoliated graphite for anode materials in lithium ion battery by controlling the intercalation/de-intercalation. The exfoliated graphite can adsorb heavy oil up to 80 g/g, it also exhibits better performance than commercial active carbon in sewage treatment. The mild-expansion exfoliated graphite as anode material shows high capacity of 370 mAh/g and good cycle performance.

Jan 1, 2014

By Steve Kral

The former mayor of Los Angeles, CA is a believer in public transportation but thinks neither his city nor the entire country is spending enough on basic infrastructure. In fact, the United States has fallen behind most other developed nations in improving public transportation, the former mayor said. Antonio R. Villaraigosa was the keynote speaker at the North American Tunneling (NAT) conference, held June 22-25 in Los Angeles, CA. The event, held every two years, is sponsored by the Underground Construction Association of SME (UCA). This years? conference attracted 1,091 underground construction professionals from around the world. The accompanying exhibition continues to grow, attracting 142 exhibiting companies occupying 162 booths. As always at NAT, registered attendees received the proceedings volume of the conference, which contains 132 papers. The proceedings volume, including a CD of the papers, is available from SME for $149 member, $139 student member and $189 nonmember. The book can be ordered from SME, NAT item #400-4, phone 303-948-4225, 1-800-763-3132, or online at www.smenet.org/store.

By P. K. Sollars, M. A. Alspaugh

In May of 1996, Twentymile Coal Co. began Longwall mining in the Foidel Creek Mine's East Mine District. These Longwall panels are some of the longest in the world (5.48 km/18,000 ft) with very difficult and challenging geometry. The conveyance system is 1,800 mm (72 in) wide, has a 4,500 mtph (5,000 stph) capacity and employs multiple tripper drives. The trippers include traditional powering designs as well as unique regeneration and braking designs. Several components were developed specifically for this application including a mobile tail brake. Control algorithms were carefully developed and tested via computer modeling. A world production record was achieved in the third month of operation and over 1 million tons were mined in June 1997.

Jan 1, 1998

By C. M. Bartley

Fluorspar, in addition to its familiar uses as a metallurgical flux and as a source of the electrolyte for aluminum production, has become important as an essential raw material in the rapidly growing fluorine chemical industry. The unique ability of fluorine to react and form compounds with al-most all other chemicals has made it one of the important elements in modern chemistry. Research and development over the past thirty years have resulted in a current annual production of fluorine chemicals that is both technically and economically important to industry. Because many of these chemicals and products are relatively new, and most have properties that are not duplicated by other materials, the present uses are expanding rapidly and new applications are being reported continually. Fluorspar, the only immediate and practical source of fluorine, is therefore an important mineral. This fact has been recognized in major industrial areas such as the United States and Western Europe, but has received little attention in Canada.

Jan 1, 1962

By E. L. Martheleur

A general expression for the electric power generated or consumed in a direct-current circuit is obtained by multiplying the reading of a suitable voltmeter connected across the terminals by the reading of an ammeter connected in the circuit. by the reading of an ammeter connected in the circuit. When alternating currents are considered, the product of the volts and amperes as obtained for direct currents does not generally represent the true energy involved; it is greater than this true energy and should be multiplied by a certain factor which may have any value between zero and unity, according to the conditions of the circuit. This factor is called the power-factor of the system, and expresses the ratio of the true energy over the apparent energy. For a three-phase system the expression of the apparent energy is [\/ 3 x E x I; ] while the expression of the true energy, that is, energy suitable for mechanical work, is [v? 3 x E x I x cos A.] The total current of a circuit corresponds to the reading of an ammeter connected in the circuit; it is the resultant of two currents. The first of these is in phase with the voltage, and is that portion which really produces mechanical work; the second is always in quadrature with the voltage, that is it may lead or lag the voltage by 90° according to the condition of the circuit. This second current does not produce any sensible work, and for this reason is sometimes called wattless current or reactive current.

Jan 1, 1924

Results of the study of chloride ion concentration effect to osmium-187 sorption from wastewater of copper smelter with use of foreign anionites of different basicity and structure are presented in the work. It was found that the increase of chloride ion concentration in the wastewater helps to increase recovery of osmium using anionites regardless of their nature. The ways to intensify the process are proposed. The method for osmium elution from the anionites with potassium iodate solution was developed. It was shown that the method lets to recover up to 99% of osmium from the anionites. Recommendations for selection of eluents for better recovery of osmium from the anionites were elaborated. Keywords: wastewater, osmium, anionite, sorption, chloride ions, eluent, recovery

Sep 1, 2012

By Frank G. Wickert

One key to maintaining successful mining operations in today?s global economy is in having the ability to access real-time machine operating data ([1] G. Brown, B. Ebacher, W. Koellner,2000)([2] Brochure of Siemens E&A, Order Number 141000-1). With recent and ongoing advances in mining equipment systems it is imperative that mine managers have full knowledge of the status of their equipment at any given point in time. This knowledge is critical to ensuring that the productivity of each and every machine is maximized. Knowledge of machine status is only the first step, however, in controlling and optimizing a piece of mining equipment. Computer based diagnostic systems, traditionally offered on mining equipment, have provided a link for collecting data and trouble-shooting problems as they occur. One problem existed, though, that those systems stopped short of providing full drive systems access. A maintenance technician could see the data but to make critical adjustments or make repairs the technician needed to be on the machine. In extreme cases the machine would be down until OEM assistance could reach the mine site. The key then to reducing down-time and maximizing machine productivity was creating a system that could not only monitor drive systems but also provide remote access to those systems. Essentially a link needed to be created through which a technician could gain drive access remotely then make adjustments or repairs without being on the piece of equipment. This paper will introduce AccessDirectTM, a new remote diagnostic system for Bucyrus mining shovels and draglines. AccessDirectTM combines all three important elements of remote diagnostics: ? Vital Signs and Production Monitoring (SiRAS-M) ? Automatic analysis (SiRAS-A) of faults, and tracking of trends for preventive and reliability centered maintenance , and ? Fast, direct Intervention (SiRAS ? I) for troubleshooting support, repairs, and system optimization.

May 1, 2002

By C Simpson

In 2011 the forecasted world demand for iron ore continues to grow, and during this time Australia is looked upon as a reliable supplier of high quality ore. The expansion of the current Australian mines is unlikely to meet the forecast demand. New mines are therefore being actively explored for and when discovered, are quickly being developed into mines in order to meet the world’s hunger for steel.The Solomon Project area is a large new iron ore discovery, located in the central Hamersley Ranges of the Pilbara province in Western Australia. The first Fortescue exploration drill holes commenced on the project in 2007 and to date three billion tonnes (Bt) of iron ore have been defi ned within the project area. Fortescue is fast-tracking the development of the ‘Solomon Stage 1’ project, with rail and mine construction commencing during 2011, and ore to be railed to Fortescue’s existing shipping operations at Port Hedland commencing in 2012. At a designed production rate of 60 Mt/a, the Solomon operation will be one of the biggest production centres of iron ore in the Pilbara.Deposit types include the three dominant mineralisation styles of the Pilbara province, being bedded iron deposits (BID), Channel iron deposits (CID) and detrital iron deposits (DID). All these mineralisation styles are present in large concentrations within the Solomon project area, and when mined will produce two product streams. These are a single product of CID, and a combined product from a blend of BID and DID material.This paper defines the geological characteristics of the Solomon iron deposits as recognised through the exploration and development of this vast resource over the three years since exploration commenced on the project.

Jul 11, 2011

By D Davis

The prediction of ground-borne noise levels from tunnel construction activities requires knowledge of the input vibration forces from the vibration source(s) into the cutting face, knowledge of the vibration transmissibility through the surrounding medium, and knowledge of the receiver building’s vibro-acoustic response. The conversion of this vibration energy into sound pressure within the receiver building depends upon the vibration coupling of the soil and the building’s foundations, the structure’s response including floor-to-floor attenuation and amplifi cation due to resonance, the radiation effi ciencies of the internal structural elements, and the room’s acoustical properties. Beginning with a known input vibration spectrum at the cutting face, it is possible to predict the resultant ground-borne noise levels within a receiver building using either analytical and/or empirical techniques, or by numerical modelling. This paper presents an overview of the various methods available to estimate ground-borne noise levels from tunnel construction activities and discusses the advantages and limitations of each.

Mar 8, 2011

During the past year a number of significant advances in geostatistics have been published. These were presented at the 13th APCOM Symposium in Clausthal, Germany and at a NATO Advanced Study Institute on Geostatistics in Rome, Italy. Of greatest importance is the work that has been done in establishing methods which correctly predict the cutoff grade-tonnage curves, and the average grade of ore-tonnage curves for deposits in which ore and waste are intermingled. Grade-tonnage curves based on estimates made from widely spaced exploration data have been found to underestimate the grade of ore and overestimate the tonnage present. This problem has been remedied by the calculation of conditional probability distributions for the unknown grade of a block. Another advance has been made in the field of geostatistical estimation for deposits in which a trend is present. Previously a technique known as universal kriging has been used, which involves much subjective judgement as to the trend fitted. A new technique, generalized increments, allows computer estimation of such deposits with much less subjective judgement. Computational efficiency of geostatistical methods has continued to improve to a point where a geostatistical estimate can be obtained for little more than the cost of any other computerized method.

Jan 1, 1976

By M. O. Pekguleryuz, D. S. Aydin

The high temperature oxidation and ignition resistance of Mg-(0-6) wt% Nd alloys have been investigated via isothermal and continuous heating experiments conducted in air atmosphere. Alloy composition is observed to be effective in low levels (~ 0.5 %) in the ignition temperature (Ti) of the alloys; the Ti of pure Mg increased from 630 °C to 770 °C with 0.5 wt% Nd addition. However, no noteworthy improvement was achieved with further additions up to 6 wt% Nd. The initial microstructure was observed to determine the oxide structure on the surface due to the differing oxidation behavior of the phases (a-Mg + Mg12Nd intermetallics). It has been found that the formation of a Nd-depleted region at the subsurface due to extensive Nd oxidation at the oxide/intermetallic interface lowers the protective ability of the oxide scale.

Jan 1, 2015

By Roy A. White

The development of a fire and rot-resistant coating treatment for mine timbers, along with the associated processing technology, is described. Included are a literature search, laboratory studies of polyimide-fungicide coatings, and leaching and fungus growth studies on coated wood blocks. Finally, an economic analysis is performed tor various levels of production.

Jan 1, 1977

By J. Kern, T. F. Torries

Identifying high value areas of unmined coal when large quantities of coal are available relative to annual markets is difficult because of the uncertainty of when the coal is to be mined. A GIS based methodology developed to value reserve coal in a producing coal region for the purpose of ad valorem taxation also identifies high value areas for mining investment. The methodology is unique in that it accounts for most mining, environmental, and market factors to determine when specific properties are to be mined. The methodology and data base are useful for directing regional exploration and acquisition activities toward most favorable areas.

Jan 1, 1999

By John Atkinson, Steve Repola

This paper will describe two blasting plans that have been developed for American Aggregates' Marble Cliff Quarry located near Columbus, Ohio. Two different limestone formations are mined on different levels of the quarry. Each formation requires a different blasting plan which address vibration considerations, crusher productivity, drilling and blasting costs and adjacent neighborhood concerns. Controlled blasting is critical to continued mining operations in this Midwest urban setting.

Jan 1, 1993

By R. A. Cattell

With the surrender of the Japanese Imperial Government as a climax to the capitulation of the German High Command , the main objective of the Petroleum and Natural Gas Division pivoted from war assignments to its main normal functions . One of these functions is to give wide public distribution to valuable technical facts which the Division has obtained through research on petroleum , natural gas , helium , and related subjects . During the war years many engineering data and scientific facts could be released only on a restricted basis as reports to war agencies and others immediately concerned . Moreover , many of the wartime reports contained masses of detailed data that were prepared under stress to meet emergency schedules . For peacetime publication and application , these data must be reviewed , correlated , and rearranged so as to present the essentials in proper form . To illustrate , a wartime report of 50 pages might be resolved into one curve in a composite graph for a peacetime publication . Another factor affecting the orientation of the work of the Division is the broader horizon of research revealed by its war activities . Fundamental research and careful engineering analyses are just as important in time of peace as in time of war; in fact , they should be more important to the forward view , because under peace conditions disrupting influences that distract from the orderly acquisition of knowledge are minimized . Therefore , the concerted effort has been not to " salvage " the results of the war activities , but to evaluate them on the basis of their relative importance in the future economy of the country . Where wartime investigations have pointed to peacetime accomplishments , the effort has been to give the corresponding type of work additional emphasis . This adjustment can not be made hurriedly , but many of the necessary preliminary steps on the new course have been taken ..

Jun 1, 1949