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By Charles E. Whieldon

Data on the oilfields in Mahoning, Columbiana, Carroll, Jefferson, and Harrison Counties, Ohio, were collected from scattered sources and compiled to make the information readily available to operators who may be interested in conducting secondary-recovery operations in the area. General geology, oil production, oil-productive acreage, core data, reservoir calculations by townships, and miscellaneous data and reference material are presented.

Jan 1, 1965

By C A. Locke, A B. Christie, J Cassidy, J L. Mauk

New and existing gravity and aeromagnetic data are used to determine the structure of the Waihi region and to investigate any relationship between structure, hydrothermal alteration and epithermal mineralisation. The 24 mGal, 10 km diameter, negative Bouguer gravity anomaly which occurs south of Waihi has been modelled as a I.5 km deep asymmetrical basin. This basin, the Waihi Depression, is interpreted to be infilled with low-density volcanic rocks of the Uretara Formation and Whitianga Group, overlying older andesites of the Waipupu Formation. To the north and west, the margins of the depression are defined by the Waihi and Mangakino Faults, which have been modelled with dips of 45 - 60¦ to the south and west respectively. The southern and eastern boundaries of the Waihi Depression are defined by smooth, shallow dipping (15 - 20¦) boundaries. The Waihi Depression is interpreted as a fault-angle depression, resulting from southeast extension in the early Pliocene. The Waihi Fault is modelled as an approximately E-W feature, located to the south of Waihi. Small 2 - 4 mGal positive Bouguer gravity anomalies occur north and west of the margins of the depression, and correlate with known areas of hydrothermal alteration and areas of low magnetic gradient.

Jan 1, 2003

By P. den Hoed, J. Nell

Tests were conducted on samples of rutile, titaniferous slag and ilmenite; each sample was mixed with coke and chlorinated in a bubbling fluidized bed at 1000°C. Profiles of the rates of chlorination of species were constructed from chemical compositions of the bed residues at different durations. From the start FeO and MnO are chlorinated quickly and all but entirely in a fraction of the time it takes to chlorinate all the TiO2. When the level of FeO is significant, as in slag and ilmenite, FeO is chlorinated faster than TiO2is. In these oxides, there is an inverse relationship between the rates of chlorination of FeO and TiO2during this first stage; the relationship, moreover, correlates linearly with the initial percentage of FeO in the oxide. We identify three stages in the chlorination process; a first, in slag and ilmenite, when FeO is being chlorinated; a second, when TiO2is most readily chlorinated; and a third, towards the end, when the levels of TiO2are reduced to those of other species. The rates at which individual species are chlorinated are analysed in terms of their appreciation or depreciation with respect toTiO2

Jan 1, 2003

By Daniel G. Di Canio

Reference information and user instructions for Version 3.0 of the Accident Cost Indicator Model (ACIM) software package are presented. ACIM estimates the tangible costs of occupational injuries, illnesses, and fatalities in the United States mining industry.

Jan 1, 1983

Removal of As(III) and As(V) in Aqueous Solution There are toxic arsenical species such as As(III) and As(V), and arsenious species have specially strong toxicity. The strong toxicity causes contamination of groundwater and water pollution for the semiconductor production process. This study is concerned with the removal of As(III) and As(V) with various kinds of Mg/Al layered double hydroxides (LDH) containing CO32-, SO42-, Cl- and NO3- as interlayer anionic species. The anion exchange property is different from the kind of layered double hydroxides and the Mg-Al-NO3-LDH is superior in the anion exchange property of As(III) and As(V) due to the nature of nitrate ion existing in the interlayer. The pH condition suitable for As(V) removal is 7.1 or more. If the initial conditions such as 10mg/dm3 of As(V) concentration, 7.1 of pH, 1 m3 of amount of solution and 99 per cent of removal are fixed, the required amount of Mg-Al-NO3-LDH is 0.27kg for two step-batch operations. The As(III) is suitable to oxidize to As(V) before the removal processing.

Sep 13, 2010

By C. Özgen Karacan

In longwall development mining of coal seams, planning, optimizing and providing adequate ventilation are very important steps to eliminate the accumulation of explosive methane-air mixtures in the working environment. Mine operators usually try to supply maximum ventilation air based on the capacity of the system and the predicted need underground. This approach is neither economical nor safer as ventilation capacity may decrease in time depending on various mining and coalbed parameters. Thus, it is important to develop better engineered approaches to optimize mine ventilation effectiveness and, therefore, to ensure a safer work environment. This study presents an approach using coalbed methane reservoir modeling and an artificial neural network (ANN) design for prediction and optimization of methane inflows and ventilation air requirements to maintain methane concentrations below statutory limits. A coalbed reservoir model of a three-entry development section, which is typical of Pittsburgh Coalbed mines in the Southwestern Pennsylvania section of Northern Appalachian Basin, was developed taking into account the presence and absence of shielding boreholes around the entries against methane inflow. In the model, grids were dynamically controlled to simulate the advance of mining for parametric simulations. Development and application of artificial neural networks as an optimization tool for ventilation requirements are introduced. Model predictions are used to develop, train, and test artificial neural networks to optimize ventilation requirements. The sensitivity and applications of proposed networks for predicting simulator data are presented and discussed. Results show that reservoir simulations and integrated ANN models can be practical and powerful tools for predicting methane emissions and optimization of ventilation air requirements.

By K. Drescher

Excavations in deep level hard rock mines show rheological or time-dependent deformation responses to mining-induced stresses. These are generally not as dramatic as those seen in soft rock environments, such as potash and salt mines, but these deformations can nevertheless become substantial in time. It is usual to see total excavation closure at a much earlier stage than predicted by numerical models, and real-time measurements underground have confirmed that closure takes place on a more-or-less continuous basis, with highest closure rates observed after a blast and then slowly diminishing with passing time. This paper describes laboratory tests to determine the time-dependent response of hard rocks to loading, the results of the tests, and then quantifies these effects to explain the time-dependent phenomena observed underground. The primary intention of this work is to help explain the various time-dependent deformation processes around typical deep level hard rock tabular excavations. Three mechanisms were investigated in two typical hard rock types present in the deep level gold mines in South Africa, namely Ventersdorp Lava and Elsburg Quartzite. Uniaxial compression creep studies were done as the first part of the study followed by shear creep studies on discontinuities where crushed lava and crushed quartzite as well as a natural gouge were used as infilling. The last part of the study consisted of triaxial post-failure relaxation tests. The compression creep tests and the triaxial post-failure relaxation tests showed that the amount of energy dissipated by the lava is significantly less than for quartzite. For mines operating at depths greater than 2000 m the implication is that the lava must show a greater rockburst-proneness than the quartzite. Since the lava shows a lower post-failure stress relaxation, it can store sufficient energy for multiple rockbursts, which is seen in the clustering of multiple seismic events in the deep level mines. This study provides the first data available for energy change calculations in fractured rock masses, and provides the first general indications for rockburst intensities ahead of active mining faces.

Jan 1, 2003

By J. M. Uys, T. B. King

WalSH, Chipman, King, and rant' have measured the water content (as hydrogen) of actual steel-making slags. An average water content of 290 ppm was found for basic open-hearth tapping slags and 114 ppm for acid open-hearth slags. Upon equilibration of these slags at 1550°C with a 25 pct H20-75 pct Nz atmosphere, the water content increased to about 410 and 300 ppm for the basic and acid slags, respectively. Walsh et al. concluded that an acid slag was thus relatively far removed from equilibrium, and that basic slags showed a closer approach to equilibrium, with the water vapor in the furnace atmosphere. Herasymenko2 contended that these conclusions were unjustified, as the oxygen pressure used in the equilibration experiments, ;bout 5 x X atm, was quite different from that found in the furnace. Consequently, during the experiments the slag composition would have changed due to oxidation of ferrous iron. As an extension of Walsh's work and to attempt to clarify this matter, the solubility of water in a basic open-hearth slag was measured as a function of oxygen pressure. Similar measurements were also made on synthetic silicates in the "Fe0"-Fe203-SiO, system. The experimental technique has been described previously by Walsh et a1.l and Uys and King.3 Samples of the basic open-hearth finishing slag, contained in 10-cc platinum crucibles, were equilibrated at 1550°C with atmospheres of different oxygen pressure but constant water-vapor pressure, Ph~o = 0.192 atm. Calculations, as well as measurements, indicate that this figure approximates the water pressure of the combustion gases in a steam-atomized, oil-fired open hearth. Oxygen pressures in the open hearth can vary from 10"2 atm in the combustion gases to between l0-' and 10" atm in the steel bath. The former figure depends on the combustion practice and the latter on the carbon content and temperature of the bath. The oxygen pressure of the slag should lie somewhere between these extremes and is expected to be closer to that of the steel bath than that of the combustion gases. Oxygen pressures were therefore varied between 10" and 6 x l0 atm. At the lowest pressure the slag "puffed up" when quenched (indicating possible loss of water) so experiments were not conducted at lower oxygen pressures. The results are shown in Fig. 1, which includes the water content of the slag "as sampled". The results show that the water content of the slag increased appreciably on equilibration with water vapor at 0.192 atm pressure and that the water solubility apparently decreases with increased oxygen pressure. The solubilities found are comparable to those of the Li20-Ca0-Si02 system.3 Work with synthetic slags in the "Fe0"-Fe203-SiOz system was performed at 1500" C, with Ph20 = 0.192 atrn and for oxygen pressures varying between 10"2 and 10-lo atm. Samples for chemical analysis were prepared as described by Larson.4 The results are shown in Fig. 2. Some low-silica melts tested at low oxygen pressures "puffed up" when quenched and analyzed less than 100 ppm water; these results are not included in Fig. 2. The melts containing 40 mol pct silica also showed a tendency to "puff up" during the quench, when they were tested at the lowest oxygen pressure. These results indicate that, at constant silica content, the solubility of water decreases somewhat with increased oxygen pressure. The effect is, however, small considering the wide range of oxygen pressures studied. Also, at constant oxygen pressure (above about lom5 atm) the solubility increases

Jan 1, 1963

By Randall M. Wheeler

Using Computer software to analyze and interpret blast vibration effects has never been so practical. Fully digital seismographs and powerful desktop and portable computers have led to the development of fast and easy to use analysis software. This workshop will focus on new Microsoft Windows-based blast vibration analysis programs developed by White Industrial Seismology, Inc. The Windows point and click graphical environment is ideal for developing full-featured and yet intuitive software.

Jan 1, 1994

By M. J. Ferrante

Laboratory-scale tests were undertaken to examine several electrolytes for possible use in separating nickel and cobalt from products being prepared at Nicaro, Cuba. The most extensive work was done with nickel sulfate-ammonium fluoride, ammonium fluoride, ammonium sulfate, and nickel sulfate-boric acid electrolytes. All four electrolytes exhibited some selectivity for dissolving nickel carbonate from Nicaro basic carbonate used for regeneration. The nickel sulfate-ammonium fluoride electrolyte exhibited less selectivity for dissolving nickel carbonate from Nicaro basic carbonate than it did from synthetic mixtures. Ammonium fluoride leaching experiments showed that a low concentration and high temperature gave a good nickel extraction with C. P. reagents; however, this was not confirmed in tests using Nicaro basic carbonate. Electrolytic tests employing ammonium fluoride leach liquors gave no further separation, since approximately 90 percent of the cobalt was deposited at the cathode with the nickel.

Jan 1, 1958

By Tex M. Kubacki

In 2007, the University of Utah Seismograph Stations (UUSS) temporarily expanded its seismic monitoring network in Emery County, Utah, in response to the August 6 Crandall Canyon mine collapse that trapped six workers. In spite of this additional coverage, no seismic events were located in the area during a six-day period (gap) from August 8 to August 13. The Mine Safety and Health Administration (MSHA) ?Command Center Log Books? however, contain references to 16 instances of underground ?bumping? and ?bouncing? that occurred during the gap. When ground truth information provided by the log books is compared to the raw seismic data recorded by the UUSS network, the correlation offers insight into the chronology of mininginduced seismicity (MIS) in the aftermath of the collapse. The new research focuses on identifying and locating seismic events that occurred during the six-day gap using double-difference relocation techniques and correlating them with log book ground truth. Ten seismic events were identified in the vicinity of the mine during the six-day gap, ranging in magnitude from coda magnitude (MC) 0.5 to 1.4. Three of these events were amenable to location by double-difference techniques. The location of one of these events is directly confirmed by ground truth information from the log books. As a result of this new research, the accuracy of Crandall Canyon double-difference locations has been improved, and the number of events correlated with ground truth information has increased. The seismic events occurring in and around the collapsed area appear in two distinct sections of the mine?east and west of the center of collapse. It was originally reported that the post-collapse events occurred in episodic clusters. The first two episodes occurred to the east, followed in time by a cluster on the west, and then by a third episode on the east. With the addition of new events to the data set, this pattern is no longer as clear, although the events still occur in clusters. Only one MIS cluster was found to occur within the bounds of the minimum estimated collapse area (Pechmann et al., 2008).

Jan 1, 2012

By M. Verri

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Jan 1, 2009

By Ruilin Yang

The following simple equations are frequently used within the blast vibration community;PPA f PPV v = 2p · , PPV f PPD d = 2p · ,a f PPV PPA 2p = , and v f PPD PPV 2p = where, PPA is the peak particle acceleration, PPV is the peak particle velocity, PPD is the peak particle displacement, and fa , fv , and fd are the frequency of the particle acceleration, particle velocity, and particle displacement vibration waveforms, respectively. Conceptually, the frequency should be selected to be the frequency of a simple sinusoidal wave that is used to approximate the blast vibration. In the literature, f is sometimes chosen as the dominant frequency (fdm) estimated from the Fast Fourier Transform (FFT) of the blast vibration wave, on other occasions, f is chosen to be the principal frequency (fpr) from the vibration cycle with the peak vibration amplitude.

Jan 1, 2012

By D Skinner, P Haeussler, D Bradley, A Christie

Mesothermal gold deposits of southernAlaska and Westland, New Zealand have both formed at the seaward edge of major collisional zones in the Pacific basin. In Alaska, production of large fluid volumes correlates in time with the addition of heat into the lower parts of the accreted terranes in the late stages of collisional orogeny. This heat was critical for driving both the metamorphic reactions that released the large volumes of fluid that carried the gold, and the contemporaneous widespread anatexis and magmatism. In Alaska's Chugach terrane, this heat as produced by subduction of a spreading ridge beneath the North America continental margin in the Eocene. The resulting products were the S-type granites and gold-bearing veins. The similar widespread S-type plutonism and gold veining in Westland's Buller terrane suggest that a similar tectonic event could have triggered ore formation along the southeastern edge of Gondwanaland. Based on the Alaskan model, a Devonian or Early Carboniferous age is favoured for high volume metamorphogenic fluid generation and gold vein formation in Westland.

Jan 1, 1995

By Peddie F, Low K, Madgwick J, Rajoka M. I, Gutierrez N, Lim C

Percolation irrigation of low-grade quartz feldspar porphyry ore with pH 2.0 H2SO4 at 510 litres/m2/day using particle sizes 1.7 - 6.7 mm in columns measuring 5 cm dia × 126 cm long was used to study effects of interrupted irrigation ('rest' periods) on metal ion release and leaching bacteria. Copper tenors increased approximately 16 fold and bacterial iron oxidation activity three fold following a 14 day 'rest'. A linear relationship between copper tenor and bacterial activity demonstrated that this experimental system was effective for quantitative studies of bacterial leaching in ore colums.

Jan 1, 1981

By S. R. Amos, N. O. Lotter, A. L. Hannaford, J. F. Oliveira, D. W. Broughton

"Ivanplats Ltd appointed Xstrata Process Support to perform the flowsheeting development work for their hypogene and supergene geomet units of the Kamoa Copper deposit, located in the Democratic Republic of the Congo. Through systematic flowsheet development using modern Process Mineralogy, the optimised milestone flowsheet delivered a saleable concentrate grade of 32.8% Cu at 85.4% recovery with hypogene ore, and a saleable concentrate grade of 45.1% Cu at a recovery of 83.4% for supergene ore. The significant value of this development is that a single flowsheet will treat both hypogene and supergene ores and produce saleable concentrates. Further work to advance the flowsheet performance has been identified for investigation in the near future.INTRODUCTIONLocation and Description of the Kamoa DepositThe Kamoa copper resource is located some 40 km west of the city of Kolwezi, in the south west of the Katanga Province of the Democratic Republic of the Congo, in the region of Central Africa. Drilling at Kamoa in 2008-2009 had discovered laterally continuous, sediment-hosted, high-grade stratiform copper mineralisation in a newly discovered copper district that forms a previously unrecognised western extension of the famous Central African Copperbelt – which hosts such world-class deposits as Kolwezi, Tenke-Fungurume, Konkola and Nchanga. This discovery showed that the western end of the Copperbelt in the Congo does not terminate at Kolwezi (Friedland & Broughton, 2009). The resource contains hypogene and supergene geomet units with a transitional zone located inbetween the (upper) supergene and the (lower) hypogene. In the hypogene unit, the major copper sulphides are bornite, chalcopyrite and chalcocite, whilst in the supergene, the sequence is led by chalcocite, then bornite, and finally chalcopyrite. Covellite is present in both units as a minor copper sulphide. Both geomet units will be mined and treated in one concentrator, either as blends or as campaigns."

Jan 1, 2013

By D. Harrington

"One of the underlying reasons for the establishment of the United States Bureau of Mines was the desire to promote greater safety in the mining and allied industries. Safety continues to be an important feature in the work of the bureau, and during the fiscal year 1929-30 the Bureau of Mines allotted $387,510 to the safety division out of a total appropriation of $2,249,670 (other than for helium).The safety division personnel consists of 22 engineers, 2 mine safety commissioners, 3 senior foreman miners, 18 foreman miners, 16 first-aid miners, 16 clerks, 10 cooks, and 3 laborers, a total of 90 persons. These safety workers are distributed through the 10 districts into which the United States has been divided for administration purposes. During the year 3 engineers, 1 senior foreman miner, 4 foreman miners, and 4 first-aid miners left the service. In general these men left the service to take up more lucrative positions.The 10 all-steel mine-rescue cars have headquarters as follows: Car 1, Reno, Nev.; Car 2, Raton, N. Mex.; Car 3, Pittsburgh, Pa.; Car 4, Terre Haute, Ind.; Car 5, Pineville, Ky.; Car 6, Pittsburg, Kans.; Car 7, Huntington, W. Va.; Car 8, Duluth, Minn.; Car 9, Butte, Mont.; Car 10, Des Moines, Iowa. There is also a mine-rescue car with headquarters at Juneau, Alaska. In addition, there have been established 11 mine rescue stations as follows: Birmingham, Ala.; Berkeley, Calif.; Seattle, Wash.; Evansville, Ind.; Jellico, Tenn.; McAlester, Okla.; Norton, Va.; Vincennes, Ind.; Wilkes Barre, Pa.; Salt, Lake City, Utah; and Pittsburgh, Pa.Every mine-rescue car and station is fully supplied with equipment and devices for use in case of mine fire or explosion, and at each station is an up-to-date automobile truck. At time of amine disaster the bureau's forces are immediately placed at the disposal of the authorities, State or company, with a view to giving such assistance as may be desired or available.The activities of the safety division at ordinary times are directed largely to securing and disseminating data on safety in mining. Among the numerous studies made, or being made, concerning safety and health in mining are those in connection with the causes and methods of prevention of mine explosions, explosibility of dust and gases, explosives and blasting, haulage, electricity, falls of persons or material, ventilation, dusts, high temperatures, timbering, lighting, machinery, and in fact practically anything which results or may result in acci¬dents of any kind in or around mines."

Nov 1, 1930

By John H. Perry

Strata III is a full-spectrum roof control system which provides the mine operator the ability to upgrade his roof control in place. The procedure is easily adaptable with current roof bolting techniques. To use the system, the operator starts by installing a special hollow core mechanically anchored roof belt during the roof bolting cycle. This bolt can be upgraded to a fully grouted tensioned rebar bolt by injecting StrataGee G-300, a special polyurethane grout, around the bolt through an injection port in the roof plate. This same bolt can then be used to inject RokLok binders for roof consolidation by pumping the binders through the core of the bolt. This concept in roof control was developed to provide the mine operator a flexible way to maintain roof control in areas which deteriorate over time, or must be kept open for long periods of time. Possible locations of use would be: longwall set-up rooms, recovery rooms, headgates, intersections, and belt entries.

Jan 1, 1987

By Jacques Ouellet, Ferri Hassani

"Within the mining industry paste backfill technology has evolved over the last two decades. This technology aims at producing safe and cost effective backfill of high strength. When used as cemented backfill underground the usual practice in the mining operations was to consider the backfill as a component under the production engineer responsibility. With its growing use in various site conditions some problems were encountered. Over time the mechanical characteristics of paste backfill could deteriorate. Investigations on these problems brought an increased understanding of paste backfill chemistry. Effectively, paste backfill is produced with tailings slurry having sometimes very complex chemistry and mineralogy. The bonding agents can be sensitive to the chemistry of these slurries. Today, a new understanding of the complex chemical reactions involved in cementing paste backfill is derived from concrete research literature. Cemented paste backfill is a manufactured product and as thus all steps involved in its making must be looked at. Both the processing engineers and mining engineers need to be involved. The proposed paper will go over the various developments and new understanding gained over the years on paste backfill chemistry. The authors had the opportunity to work with various Canadian mines that implemented paste backfill in their operations. Chemical alterations case study will serve to illustrate the importance of a good understanding of cement and paste chemistry. The authors will then conclude on research orientations needed to bring a more efficient use of paste backfill technology. The crucial role of the processing engineers in the paste backfill manufacturing will be discussed.INTRODUCTIONPaste backfill is usually prepared from a mixture of solids and water containing at least 15% particles smaller than 20 microns with the addition of binders for mechanical strength. Historically, tailings had been classified to extract the fines and only the coarse part was placed underground as sand slurry. Paste fill was researched in the last three decades to enable mining operations to use all the tailings, including fines, in backfill. The outcome of the early studies showed that paste fill provides high strength but due to preparation complexities and transportation problems is expensive. A greater understanding of the transportation mechanisms and advances in dewatering technology in recent years has resulted in more practical use of paste backfill."

Jan 1, 2002

By A Bax, G Wardell-Johnson, A Giblett, W Staunton

This paper presents a number of key considerations for process development testwork as a reliable basis for the inclusion of gravity separation in gold recovery flowsheets. Operating data, experiences and numerous case studies are also discussed in support of identifying best practice principles for gravity circuit design.CITATION:Giblett, A, Bax, A, Wardell-Johnson, G and Staunton, W, 2013. A review of best practice in gravity circuit design and operation, in Proceedings MetPlant 2013 , pp 272-284 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 15, 2013