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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 J. E. Gill

Introduction During the past summer, detailed geological mapping was extended to cover the entire group of 31 claims owned by Waite-Ackerman-Montgomery Mines, Ltd., and considerable new information was revealed by development and exploratory work underground. These new facts provide a more complete view of the lithology and structure of the area than has heretofore been available. They also necessitate revision of certain interpretations presented last year by Peale (l), and have served to straighten out some of the problems suggested by Porritt (2). The purpose of this paper is to outline in a broad way the relations as now understood and to discuss in detail certain points which should be of interest to members of the Institute. Maps and records by the mine staff have been freely used in arriving at the interpretation presented in the following pages. The writers are especially indebted to Mr. R. V. Porritt, the mine manager, with whom many of the problems touched upon were discussed on the ground and whose intimate knowledge of the geology of the underground workings aided greatly in testing various hypotheses. The writers have profited greatly, also, from close association with Dr. W. F. James during the course of the work. Permission to publish the included data has very kindly been given .by the management.

Jan 1, 1932

By P. C. Benedict, J. A. Titcomb

"The following description of the geology of the Northern Empire mine is recorded by the senior author, but is based on the observations and complementary mapping of both authors.The Northern Empire mine is a mile east of Beardmore, and 100 miles northeast of Port Arthur, Thunder Bay district, Ontario.Production started in March, 1934, and terminated in September, 1941. The total number of tons milled was 425,866, from which 153,103 oz. gold was recovered. The lowest level from which ore was mined was the 1,900- foot, but considerable drifting was performed on the 2,075-foot and 800 feet on the 2,415-foot, the deepest level,The vein strikes about N.72°E. and has an average dip of80°S. In stoped sections the quartz averaged about 2 feet wide. On the 1,725-foot level it was drifted on continuously for more than 7,000 feet. In the mine as a whole, practically no commercial ore was found beyond points 1,400 feet west and 1,800 feet east of the shaft. Conspicuous wall-rock alteration extended throughout this section, but not much beyond these limits. There was some splitting of the vein and widening of the alteration halo on the lower levels. The average general colour of the quartz changes with depth .The vein is in 'Keewatin' lava flows, to which it is almost conformable. It lies only a short distance south from the 'Timiskaming-Keewatin' contact ( Fig. 2). This contact is marked by a black graphitic fault. So far as is known the fault is parallel, or nearly parallel, with the flows in strike, but dips at 72°S., which is 5° flatter than the average dip of the overturned flows. A post-vein, almost flat sheet of diabase about 550 feet thick cuts outthe vein from about the 650- to the 1,200-foot level ( Figs . 1 and 3). If it was intruded along a fault, the fault had only minor displacement. A strong alteration halo extends to 200 feet above and below the diabase. The vein was conspicuous but in large part it was below ore grade for 100 feet or more above and below the diabase.-"

Jan 1, 1954

The Kalgoorlie Golden Mile is proposed as an Archaean volcanogenic-type deposit, modified and redistributed along later-developed structures. Rich pyritctelluride and Green Leader gold mineralization is associated with the end phase of basic volcanism and, in a general sense, is confined to a broad interface zone between the products of marine basic volcanism and later acid volcanism. There is virtualIy no ore associated with the main body of acid volcanics.Green Leader is the local name of a type of ore that occurs at some igneous rock contacts in association with graphitic sediments and layered acidic tuffs. It is characteristicalIy green, of various shades, and commonly yields very high gold assays, the reasons for which are not apparent in hand specimen.Carbonates, carbonaceous shales, tuffites, rich gold ores, and acid and intermediate dykes, alI indicating a common heritage, are features common to the main ore hosts, viz. the Paringa Basalt (Calc Schist) and theGolden Mile Dolerite ("Quartz Dolerite Greenstone").Several probably related fracture systems have reconstituted most, but not all, of the original deposits into a large number of steep tabular lodes.Includes two sets of discussions and comments from later Proceedings volumes.

Jan 1, 1974

By Shirley F. Colby

A continued rise in construction activity in 1941 forecasts further increases in the demand for building materials of mineral origin, Recent studies by the Bureau of Mines, United States Department of the Interior, reveal that sales of mine and quarry products and their derivatives as a class have followed the long-term trend of construction activity in the past and are benefiting now by the upswing in all types of building. At present most building materials of mineral origin are holding their own in the competitive arena. A few are slipping behind, but others have forged fax ahead. Prominent among those that have surpassed general construction activity since 1925 are sand, gravel, and crushed stone (used in concrete and road metal and railroad ballast) and cement. Both building stone and roofing slate have followed the building curve closely, although in the last few years sales of roofing slate have risen above the curve and sales of building stone have dropped below it. Clay products and building lime, on the other hand, have lagged behind the general procession. Gypsum sales likewise dropped behind, but during the last few years, this industry, thanks to the wider acceptance of its newer products, has staged a marked recovery so that it now stands in about the same relation to total construction activity as it did is 1927-25.

Jan 1, 1941

By E de Necker, F D. I Hodg, L-M Cruywagen

The acid mine drainage (AMD) situation at three opencast collieries in the Witbank Coalfield, South Africa, was evaluated from different perspectives. Twenty-seven test pits were dug into the spoils of these collieries to characterise the in situ conditions of spoils of varying age. Detailed static testing was done on surrounding drill holes and additional samples were taken from the test pits. Selected samples were tested using different techniques, namely ABA, mineralogy and kinetic tests. Groundwater monitoring boreholes from the areas surrounding these spoils were also used for characterisation. The ABA results compared favourably with the in situ determinations; acidic test pits proved to be potentially acid-generating from ABA, even when the samples had neutral paste pH. Kinetic test results showed these samples to yield low pH leachate over the test period. In several of these results, the theoretical depletion of neutralising potential and the onset of acidity were well matched. NAG pH-values and final observed water chemistry corresponded for the cells predicted by ABA to acidify, but compared poorly in cells that did not acidify. Results from the non-acidic spoils were consistent with the in situ observations. Alternative kinetic test methodologies were also employed. Duplicate samples were tested in humidity cells and in aerated trays that were manually wetted on a regular basis. Results from these tests showed an excellent correlation. Detailed mineralogical determinations using XRD and XRF were used for comparison to the ABA and, in some cases, humidity cell results. These comparisons show that the ABA results are consistent with the results expected from the mineralogy. The conclusion from these assessments is that ABA, in most cases, provides information that can be correlated to the field, mineralogy and to humidity cells. The use of multiple techniques leads to a higher degree of confidence in the use of the data.

Jan 1, 2003

By Flavio Begazo, William A. Enrico

"Southern Peru Copper Corporation's Ilo Refinery, the largest in Peru, began operations in 1975 with a production capacity of 165,000 stpy. Southern Peru bought the Refinery from the state owned Minero Peru SA on June 1, 1994.The Refinery processes blister from Southern Peru's I/o Smelter. Blister copper is processed in an anode plant equipped with two 365 st tilting reverberatory furnaces, a 26 mold casting wheel and an anode press machine. Copper is electrorefined in a tank house equipped with 768 commercial cells, 44 stripper cells, and 40 liberator cells, utilizing two electrolyte circuits and a 21,000 Ampere rectifier.During 1989 through 1994 a program for improving productivity was carried out by increasing the number of cells and increasing current density to the total rectifier capacity. As a result, a capacity 215,000 stpy of refined copper, 2 million tr. oz silver and 6,000 tr. oz gold per year was achieved. In 1994 Southern Peru announced plans to increase capacity to 250,000 stpy of cathode with a US$ 18 million investment and a US$ 2 million investment in environmental improvement projects, as part of the purchase agreement with the Peruvian government.This paper outlines the scope of the SPCC lio Refinery modernization and environmental program. It describes the implementation of the Electrolytic Plant expansion based on instaliation of polymer concrete cells, a new rectifier, a new selenium roaster and a Precious Metal Plant upgrades."

Jan 1, 1997

By Kent R. Van Horn, W. P. Sykes

Since Honda and Murakamil in 1918 proposed their constitutional diagram of the carbon-free iron-tungsten system, considerable effort has been expended by several investigators in attempts to define more positively the structural features of the alloys. The existence of an intermediate phase corresponding to the formula Fe3W2 (68.7 per cent W) was proposed from evidence of a purely metallographic nature by one of the present authors2 in 1926. Since that time the identity of this phase has been confirmed by Arnfelt3 and by Takeda,4 both of whom employed X-ray methods as well as the microscope and the chemical analysis of isolated microconstituents. According to Arnfelt, Fe3W2, as crystallized from the iron-rich melts at a temperature above 1450° C., contains by analysis 68.7 per cent W. The lattice of this phase is characterized by trigonal symmetry. Arnfelt, moreover, proposed a second intermediate phase formed at some temperature between 1450" and 1000" C. by a peritectoid reaction involving Fe3W2 and the iron-rich solid solution. A melt containing 25 per cent W was cooled to 1000" C. and heated for 100 hr. The precipitated tungsten-rich constituent was separated and found by analysis to contain 62.6 per cent W. This composition agrees closely with that represented by the formula Fe2W (62.2 per cent W). Diffraction patterns from the concentrated precipitate showed a hexagonal unit cell. Takeda confirmed the data of Arnfelt regarding Fe3W2 but was unable to detect Arnfelt's second intermediate phase. While Takeda failed to describe in detail the treatments employed, he stated that in alloys containing 40 per cent W which were quenched after heating at various temperatures between 1200" and 1450" C. no evidence of the second phase (Fe2W) was observed 'either in the microstructure or in the diffraction patterns of isolated residues. He therefore considered the existence of this low-temperature hexagonal compound as disproved.

Jan 1, 1933

By R. D. Wunder

The Chino Mines Company, a Kennecott-Mitsubishi partnership, located in Hurley, New Mexico, recently completed a $405 million modernization of its mine, concentrator, and smelter facilities. The mine/ concentrator modernization commenced in 1980 and the smelter modernization began during 1982. Modernization of the mine and concentrator facilities involved increasing the mining rate from 98 kt/d (108,000 stpd) to 152.2 kt/d (167,800 stpd). Ore mining was designed to increase production from 20.2 kt/d (22,300 stpd) to 34.0 kt/d (37,500 stpd). A new concentrator was constructed near the mine using semi-autogenous grinding. The new smelter uses the INCO flash smelting process, increasing capacity by 40.8 kt/a (45,000 stpy) to 99.8 kt/a (110,000 stpy) of salable copper.

Jan 1, 1985

The treatment of mixed lead carbonate and lead sulphide concentrates at Mount Isa presents a problem which is unique ,in the lead smelting world; a problem whose solution is far from simple, and is not yet complete. Two years of study under plant conditions have definitely proved, however, that a most satisfactory sinter can be made in a single-pass roast.The object of this paper is to present a brief record of the development of the single-pass roast and a resume of current practice in the smelting plant. The sintering operation is discussed in greater detail, as it is upon this phase of the work that every item in the smelter operating programme depends.The smelter, to-day, presents a very much simplified layout, equipped for economical, straightforward operation, requiring, however, very careful and constant supervision, due to the extreme delicacy of the sintering operation and to the rapid and wide variati9n in the nature of the concentrates which are to be handled.

Jan 1, 1933

By I. R. Hanby

A simple but comprehensive method has been developed for the simulation of a mechanical-drive dump truck that enables various parameters to be predicted as a function of time throughout its whole cycle. Uses of the simulation results are indicated with specific attention to environmental and operational or economic planning. The output of a sample run is presented. The method can be easily adapted for the investigation of a wide variety of mobile plants.

Jan 4, 1992

By K. V. Raj, VASU GANGRADE

Airflow in large-opening stone mines is largely dependent on the natural ventilation due to the large cross- section area of the opening. The openings of such stone mines are typically twice or thrice the size of typical underground coal or metal/nonmetal mines. Due to the influence of natural ventilation, air velocities as well as the static pressure drop in the mines are low. Mines rely on auxiliary fans to ventilate active faces to reduce contaminant exposure to mine workers. The National Institute for Occupational Safety and Health (NIOSH) is conducting research on ventilation of large-opening stone mines to reduce worker exposure to dust and other contaminants such as diesel particulate matter (DPM). In order to reduce worker exposure to dust and DPM, an understanding of the airflow pattern due to auxiliary fans in the mine is needed. Under this research, NIOSH researchers are exploring the computational fluid dynamics (CFD) modeling to understand the airflow behavior in large-opening mines. In this paper, the team is presenting the results from three-dimensional CFD modeling of airflow in a large-opening stone mine and investigating the effect of a fan placement with the movement of trucks.

Feb 1, 2025

By Armando Vazquez

This paper will provide an overall technology update on Tenova’s modular i BOF® technology package for improved endpoint detection (Carbon and Temperature), slop detection and auto-tapping control, with a primary focus will be on Tenova's Slop Detection System (SDS). Accurate Slopping prediction is a critical tool in the operation of a BOF. It provides the steelmaker with an additional protective system to increase yield & productivity while reducing operating costs. Tenova Goodfellow's i BOF® slop-detection technology uses lance vibration analysis with real-time alerts to give steel makers advance warning of the onset of a slop and a measurement of the slop severity. The system is designed to provide direct feedback control of lance position and oxygen flow rate, for rapid mitigation of potential slopping events. This paper will provide a summary on how the i BOF® technology package has been implemented, including trials and general results.

Jul 30, 2018

By Rudolph P. Frizzi

Structures supported on ACIP and DD piles perform successfully when quality control is maintained from the initial site subsurface investigation through pile design, bidding, and construction. The four stages of ACIP / DD pile construction are: preparation, augering the pile, grout / concrete placement, and reinforcement installation. During all four stages, careful observations and communication between the contractor and the owner's engineering inspection personnel are vital to successful pile completion. Automated monitoring equipment (AME) exists to supplement, but not replace, the field personnel's observations during the pile augering and grouting operations. Full-scale field load testing is done to verify the pile's geotechnical and structural design, and the contractor's pile installation means and methods, using several procedures including: conventional top loading, high-strain dynamic, rapid axial compression (i.e. Fundex PLT and Statnamic), and Osterberg Cell. Non-destructive sonic testing is performed to investigate the below-grade sectional properties of the completed pile; such methods include: low-strain impulse testing, and single-hole and cross-hole sonic logging. Post-construction observations are necessary to verify pile location and top properties prior to overlying cap construction.

Jan 1, 2005

By P Breuer, A Simons

The sulfidisation, acidification, recycle and thickening (SART) process is currently being used at NewcrestÆs Telfer Gold Mine to recover cyanide and copper from the cyanidation tails of the pyrite concentrate carbon-in-leach (CIL) process. While the process has been effective at attaining high recoveries of cyanide and copper, the Telfer SART plant has experienced higher than expected sulfide additions to achieve these recoveries. This paper details the results of surveys on the Telfer SART plant, which show that residence time appears to be causing the high sulfide consumptions. The paper also details the results of laboratory scale experiments which confirm the observed residence time impact during the acidified stage of SART.CITATION:Simons, A and Breuer, P, 2013. The impact of residence time on copper recovery in Telfer Gold MineÆs cyanide recycling process, in Proceedings World Gold 2013 , pp 189-196 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 26, 2013

By W. F. Watts

The U.S. Bureau of Mines has conducted research on methods to reduce and to measure diesel particulate matter (DPM) aerosols in underground coal mines. One objective of this report is to present findings from an investigation of the DPM reductions obtained by an engine-mounted integrated control system consisting of a dry system (DS) and a diesel particulate filter (DPF). Another objective is to present results from the usc of a size selective personal sampler to measure DPM concentrations in an underground coal mine. Bureau laboratory tests of the integrated dry system and diesel particulate filter (DS-DPF) have shown that DPM emissions can be reduced up to 97 pet with little change in gaseous emission concentrations. The DS-DPF is undergoing certification tests conducted by the Mine Safety and Health Administration (MSHA). Subsequent to passing all safety requirements, it will be tested in an underground coal mine. A baseline survey of DPM concentrations and aerosol size distributions in a cooperating mine was completed in August 1988. A prototype DPM personal sampler was tested during this survey. Based on results from this test, an improved unit has been developed. This unit is scheduled for extensive field testing by MSHA in 1989.

Jan 1, 1989

By S Hapugoda, J R. Manuel, M J. Peterson, A Poliakov, E Donskoi

The occurrence and deportment of manganese in a number of ferromanganese and Mn-bearing iron ore samples from supergene-upgraded deposits, as well as from magnetite banded iron formation (BIF) and magnetite skarn deposits, was characterised in order to provide a basis for improved understanding of the processing characteristics of different ore types and investigate the potential for development of a robust geometallurgical classification for Mn-oxide ores. An understanding of the Mn mineralogy in mixed Fe-Mn deposits is necessary to inform any attempt to separate the Fe and Mn during beneficiation and to understand and predict the behaviour of lump and fine ore products during processing.A suite of analytical techniques was utilised, including hand sorting of lump ore particles, optical microscopy, X-ray fluorescence (XRF)/inductively-coupled plasma mass spectrometry (ICP-MS) chemistry, X-ray diffraction (XRD), scanning electron microscopy (SEM)/electron probe microanalysis (EPMA) and gas and solid phase pycnometry, in order to elucidate manganese mineralogy, mineral chemistry and mineral textures. Manganomelane group minerals (eg cryptomelane, hollandite), pyrolusite and lithiophorite were the most common manganese oxides in the samples examined. From the microprobe work, there was evidence of probable substitution of Mn, as well as Al and Si, into the structures of goethite and hematite. Manganomelane minerals were often intimately associated with goethite, in particular, and a clarification of this association and the associated Si and Al impurities is fundamental for improved understanding of beneficiation and sintering behaviour of Mn-oxide ores. Due to the poor or very fine crystallinity of some supergene manganese deposits and of some Mn oxide minerals, in particular the extent of overlapping peaks and their variable mineral chemistry, XRD was a problematic technique to equivocally determine Mn mineralogy.For lower-grade, earthy, poorly microcrystalline ores the mineralogical and textural association between mixed Mn, Fe and Al (¦ Si) phases was also critical. The deportment and potential separation of these elements in these deposits, especially Al, was complex, as they were characterised by forms of æhydrousÆ cryptomelane with higher levels of Fe-Al-Si substitution, as well as intimate intergrowths of ochreous-earthy goethite (probably aluminous in part) with cryptomelane, lithiophorite and/or kaolinite.Trace amounts of alkali elements in ferromanganese deposits were considered likely to be preferentially structurally associated with Mn oxides, while lateritic deposits with significant amounts of lithiophorite could contain elevated levels of deleterious impurities; Co and Ni in particular.A combination of solid and gas phase pycnometry proved to be a useful technique for broadly discriminating hematitic, goethitic and mixed Mn oxide-goethite lump particles based upon differences in their envelope and apparent densities. Based upon these preliminary results and ongoing Raman spectroscopy work on manganese deposits sensu stricto, Raman spectroscopy is a technique considered to have promise during targeted research to better link the optical and compositional properties of ferromanganese ore particles. CT-scan (computed tomography scan) analysis could also be combined with Raman spectroscopy and pycnometry to link mineral composition, mineral texture, ore particle textures and particle porosity/permeability to the high-temperature processing behaviour of lump and fines products.CITATION:Peterson, M J, Hapugoda, S, Manuel, J R, Donskoi, E and Poliakov, A, 2013. Textural characterisation of manganese minerals to improve the geometallurgical characterisation of ferromanganese and iron ores, in Proceedings Iron Ore 2013 , pp 281-300 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 12, 2013

By F. L. Bosqui, A. D. Wilkinson

EVEN though the world has not been crying for more copper for the last three or four years there has been some important mill and smelter construction. Discovery and development of large new high-grade copper deposits in Africa has led to the construction of extensive reduction facilities there, prominent among which is the concentrator and smelter of the Rhokana Corporation at N'Kana. Northern Rhodesia. The 3000-ton concentrator adjoins the central shaft. A little over half a mile to the southeast, at an altitude of 40,010 ft., is the smelter, designed on the site by 1. H. Wynne. It is arranged primarily to treat N'Kana copper concentrates, but can also handle concentrates and direct-smelting ore from outside sources. Excavations were started late in 1930; concrete was first poured on Jan. 6. 1931; and the first blister cop¬per was cast on March 1.9, 1932, less than fifteen months later. During this period, which included several months of heavy tropical rains, some 10,000 cu. yd. of concrete was poured and 41000 tons of structural steel erected under the supervision of construction engineer, A. Ek, with a labor force of 60 to 30 Europeans and about 300 natives. The steelwork was fabricated by Head Wrightson & Co. in England, and the boiler plant equipment furnished and erected by the International Combustion Co. Ltd.

Jan 1, 1934

By M. Abouhamad

According to the Canadian Urban Transit Association (CUTA), 140 Billion CAD is required to maintain, rehabilitate, and replace subway infrastructure between 2010 and 2014. The current practice adopted by transit authorities for prioritizing subway stations for rehabilitation is based on the station structural needs. While this classification is reflective of station condition, other factors, such as station size, location and passenger capacity, play an important role. The criticality of a station is an index that represents the functional importance of a station depending upon a set of identified factors. The system criticality is based on several attributes, such as station location, size, and nature of use. This paper presents a novel method of clustering subway stations for rehabilitation priority based on their criticality level. The different stations in a subway network are rated according to their relative importance against predefined attributes. The weights and scores of the attributes are computed with the help of experts and current subway network data. The analysis is done using the Fuzzy Analytic Network Process (FANP) to accommodate the subjectivity of human judgment as being expressed in natural language which entails ?fuzziness? in real-life problems and account for the interdependency between the selected attributes. The output of the model is a criticality based clustering of subway stations. The proposed framework helps authorities prioritize stations for rehabilitation and highlight stations with more criticality for a more robust asset analysis.

Aug 1, 2013

By H. D. Kline

Manganese ores have been mined in the Batesville district since 1849. Although not continuous over the intervening years, production had totaled approximately 432,000 tons of manganese ore and ferruginous manganese ore to the end of 1953. The ores occur in deposits, essentially low in manganese content, distributed over an east-west belt 24 miles long and 4 to 8 miles wide, the core of which is about 6 miles north of Batesville, Independence County. Although the reserves of high-grade ores in the district are comparatively small, the large deposits of subgrade ores and low-grade manganiferous material comprise potential sources of supply of manganese that may have increasing future importance. The manganese occurs as primary oxide and carbonate minerals in relatively flat-lying limestone and shale formations in which they were originally deposited and as oxides in residual clays resulting from decomposition of the shale and lime-stone. Most of the deposits underlie from a few to over a hundred feet of sedimentary chert, but many occur in the residual clays on exposed slopes of chert-covered hills.

Jan 1, 1956