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By Barbara H. Carroll

In order to rapidly evaluate an area for its mineral potential, a reconnaissance exploration program generally includes the following: 1. Outlining an area of interest 2. Identifying known mineral deposits 3. Bibliographic search of the literature 4. Evaluation of geochemical and geophysical surveys 5. Compilation and review of geologic maps The information now available from various government agencies regarding the mineral deposits, geology, and geochemistry may be integrated and used as a tool to rapidly evaluate an area before the field season. The databases most commonly used in the United States are the USBM MAS/HILS system and the USGS MRDS system for their information on mineral deposits; GEOREF and GEOARCHIVE for bibliographic information; and NURE data for the geochemistry and geophysics. In conjunction with the project geologist, this information may be used to plot known deposits and their geochemical signature as well as any other areas of like signature for further examination.

Jan 1, 1985

By C. H. Riggs

This report describes the development, oil recovery, and potentialities of productive formations in the Hall-Gurney field, Russell County, Kans. It is presented as part of a general program to aid and promote increased recovery from petroleum reservoirs. The report is based on studies of well logs, drill cuttings, and oil-and water-production histories of individual wells and leases. The geological interpretations follow closely those in published literature with only slight local modifications. Oil and water analyses, made at a Bureau of Mines research center, were supplemented by many analyses obtained from oil-producing and service companies. The Hall-Gurney field, in south central Russell County, Kans., (fig. 1) was discovered in 1931 but was not developed extensively until 1941. By 1960 the rate of oil production from the field had declined to the extent that many wells were abandoned. In some areas natural productive forces have effected good recovery. However, in other areas inefficient waterflooding, both natural and accidental, has adversely affected recovery potentialities.

Jan 1, 1963

By S. R. Bryan, J. D. Stephens, D. R. Rothbard

The distributions of gold and associated elements in mineral grains from a pyritic gold ore were studied by optical microscopy, and by SEM and SIMS imagery. Products studied were a sulfide flotation concentrate, a calcined sulfide concentrate, a cyanide leached calcine, and a cyanide leached pressure oxidation residue. Individual pyrite grains are compositionally zoned and solid solution gold occurs in some, but not all zones. Most of the gold in calcined products is present as metallic coalesced grains that are smaller than 100 angstroms. Gold lost into cyanide leached residues from the calcines tends to be in “semi-dense” grains that cannot be distinguished from gold-free grains except by SIMS analysis. The gold in cyanide leached pressure oxidation residues occurs as solid solution gold in unoxidized pyrite remnants.

Jan 1, 1990

By O Dominguez

Significant value can be added to ore supplied from the mine to the mill by measuring its quality in real time and performing grade control additional to that within the mine. Responsibility for ore quality between the mine and mill stockpiles is not always clear due to operational siloes so geologists and mining engineers need to be involved collaboratively with metallurgists to optimise ore value prior to processing. Sensors, such as the GEOSCAN-M which utilises high specification Prompt Gamma Neutron Activation Analysis (PGNAA), that measure conveyed ore flow representatively (continuous and fully penetrative) and in real time have been used in the minerals sector since 2003 and have been successfully applied in multiple commodities. Quality can be measured within the mine where material is conveyed underground or in-pit. Bulk ore sorting is used to divert increments of waste from the ore stream to upgrade material sent to the crushed ore stockpile (COS) as well as to create run-of-mine (ROM) stockpiles of different qualities to maximise blending opportunities and accommodate processing priorities, eg blending out deleterious content. The real time composition measurement can be combined with moisture and fragmentation analysis data for improved ore type characterisation, to control ore blending, for feedback to the mining schedule and block model reconciliation, and feed forward control for grinding and processing operations. The paper discusses various parameters measured and derived in existing operations that are used to maximise coarse waste rejection and metal recovery, optimise plant feed quality consistency, and reduce consumables; power, grinding media, water, reagents, and minimise fine tailings generation. Innovative geometallurgy applications are also discussed.

Mar 22, 2022

By Kal V. S. Sastry

Comminution is an important unit operation of mineral processing in terms of large tonnage of materials processed, huge energy consumption, and high capital and operating costs. Substantial research efforts have been directed towards the development of process-engineering tools including mathematical models, process scale-up procedures and computer simulation packages (Austin et al., 1984; Rajamani and Herbst, 1990; Kawatra, 1992). The simulation systems are found to provide significant cost savings by enabling efficient circuit design and development of control systems. Most of these simulators are built from scratch, do not make use of software modules from other sources and are designed with minimal usage of formal software methodologies.

Jan 1, 1995

Effect of Anionic Surfactant on Silica Particle Attachment at the Oil-Water Interface Controlling particle attachment is crucial where powdered solids come into contact with oil and water. Particles are trapped in a deep energy well at the oil-water interface, stabilising emulsions. Here it is shown that adding anionic surfactant causes dramatic changes to the bulk and interfacial structure of silica particle-stabilised oil-in-water emulsions. Exposing particle-stabilised drops to surfactant concentrations above the critical micelle concentration enhances the rate and extent of creaming and flocculation. Mixing particle-stabilised emulsions with surfactant solutions causes drop fragmentation. As the surfactant concentration increases, the average drop size decreases and particles are displaced from the interface during the mixing process.

Sep 13, 2010

By Hal W. Hunt

Steel and concrete piles and power-actuated hammers have developed almost entirely within the past 100 years. Prior to that time, piles were mostly timber, driven with a drop hammer or a maul. The Engineering News Formula ? for timber piles driven with a drop hammer at a factor of safety of six ? was promulgated by Wellington in 1888. Steel com­panies supplied fabricated and rolled shapes for piles in the early 1900's. The thin shell and then uncased concrete piles originated about that time. Now leads have become sophisticated to accurately spot a pile at any required batter. Hammers have grown to phenomenal size and vibratories are being accepted at full value.

Jan 1, 1984

By Joshua Hofman, Braden Lusk, Erin Morris

Explosions in urban environments, whether of accidental or malicious cause, often result in extensive injuries, loss of life, and property damage. The ability to predict the damage inflicted by these events is highly sought after; in order to predict damage, the behavior of blast waves within these environments must be quantified and understood. Urban constructs such as buildings and roadway intersections affect the natural propagation of a blast wave, intensifying or rarefying the wave depending on their arrangement.

Jan 1, 2012

By Isabel F. Barton, J. Brent Hiskey

Chalcopyrite (CuFeS2) is the earth’s most abundant copper ore mineral, but is refractory to leaching with sulfates, chlorides, and other common lixiviants and oxidants. This has led to increasing research into alternative lixiviants for recovering Cu from chalcopyrite. Here, we review the leach kinetics of chalcopyrite in glycine, ionic liquids, and methanesulfonic acid, compared to baseline ferric sulfate and ferric chloride. Glycine (CH2NH2COOH) has long been used in applications such as biocatalysis and electroplating, and has recently been examined as a lixiviant for whole ores and concentrates of both copper and gold. It is nontoxic, biodegradable, and capable of strongly complexing Cu2+. Compatible oxidants are peroxide, dissolved oxygen, and ferric sulfate. Chalcopyrite leaching rate in glycine is chemical reaction-controlled, but the effects of grain size and the reaction orders with respect to lixiviant and oxidant concentrations and mass transfer vary. The use of ionic liquids as a leaching agent for chalcopyrite has been extensively investigated in recent years. This system is based primarily on the use of the imidazolium molecule (C3H5N2), which is a planar 5-member ring structure. This lixiviant has been applied to the leaching of chalcopyrite in the form of pure mineral, concentrates, and ores. Kinetics of ionic liquid leaching of chalcopyrite vary substantially depending on the type and concentration of ionic liquid. Methanesulfonic acid (HCH3SO3) is one of the newest lixiviants available in leaching, having only been examined in the last decade. It has been examined as a substitute for sulfuric acid, since it is less corrosive, is biodegradable, and breaks down to carbon dioxide and sulfate over time. The rate of copper leaching from chalcopyrite by methanesulfonic acid is controlled by diffusion and exhibits a strong dependence on oxidant type and concentration. Despite promising reaction rates and total extraction by some of these novel lixiviants, comparison with baseline ferric sulfate and ferric chloride systems makes it doubtful that any will be commercially viable in the near term. Only at very high reagent concentrations and temperatures, and/or very fine grain size, did any of the systems perform comparably to the much cheaper ferric chloride at extracting Cu from chalcopyrite. Most had similar overall reaction rates and total extraction to ferric sulfate, which is relatively common and cheap. However, the leaching kinetics of these novel lixiviants offer valuable insight into the dissolution behavior of chalcopyrite in various systems.

Jan 1, 2019

By M G. Wansbone, R Bhargava

The inferred ground conditions for the proposed mined cross passages at the northern end of the Waterview Connection tunnels consist of an overburden of alluvial and residual soils, with mixed face geology of highly weathered to unweathered extremely weak rock. This paper describes three-dimensional (3D) finite difference analyses undertaken to evaluate the stability of the cross passage headings and to validate the proposed sequence of excavation. The analyses undertaken incorporated the influence of the construction of the mainline tunnels and the breakout opening in the segmental lining for construction of cross passages.The stability analyses were carried out using FLAC3D™, version 4.0 (by Itasca Consulting Group) by progressive reduction of shear strength parameters to obtain a failure condition and estimate a factor of safety. For each step of strength reduction, corresponding increments of displacements of several points on heading faces were monitored. The stability obtained from numerical analyses was compared with analytical solutions. Interpretation of results of drained analyses indicated instability of the upper 2 m of heading face within the highly weathered rock mass. Additional analyses were undertaken by including grouted fibreglass dowels to reinforce the heading face. The results of the additional analyses showed significant reduction in displacements and yielding of ground around the face. The proposed temporary support comprised face reinforcement using grouted fibreglass dowels in conjunction with canopy tubes and perimeter support of steel fibre reinforced shotcrete. The stability of the construction sequence, which was related to the specific requirement of the proposed excavation equipment, was validated.CITATION:Wansbone, M G and Bhargava, R, 2014. Analysis of stability and design of face support for cross passages – Waterview Connection tunnels, Auckland, New?Zealand, in Proceedings 15th Australasian Tunnelling Conference 2014, pp 339–344 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 17, 2014

By K. Lillkung, O. Forsen, J. Aromaa

"The dissolution rates of Pt, Pd and Rh in 250 g/L NaCl solution were calculated from the current densities determined by polarization curves and potentiostatic measurements measured with wire electrodes at atmospheric pressure. The results achieved with the two methods were similar. The dissolution rates at the corrosion potential were in the order of few nanometers per hour. The polarization curves indicated that to achieve dissolution rates required for economical operation on an industrial scale, the samples need to be polarized to higher potentials. When polarized to higher potentials, the metal dissolution rates were in the order of micrometers per hour. As the Tafel slopes of the metal dissolution region are fairly steep, the potential affects the dissolution rate greatly. Based on the activation energies, the dissolution reactions were controlled by a charge transfer step.IntroductionPlatinum group metals (PGM) have some very unique properties such as their inertness, giving excellent corrosion resistance, and a high melting point. At the same time, these factors make the refining of these metals very challenging. The main applications where PGMs are used are different catalytic converters, mostly in automotive catalysts. The used catalysts are also an attractive secondary source of PGMs. The exact concentrations of PGMs in catalysts vary widely depending on the manufacturer, the age and the capacity of the catalyst. The concentration of Pt in a new catalytic converter range from 300 to 1000 ìg/g, Pd from 200 to 800 ìg/g and Rh from 50 to 100 ìg/g [1]. Precious metal catalysts usually consist of a coat of the metal supported on ã- alumina. The recovery of metals from automotive catalysts has received much attention during the last few years [1-3]. In the near future, the use of PGMs in fuel cells is predicted to increase the amount of secondary PGMs available [4]."

Jan 1, 2012

By U. Petersen B

El presente estudio señala la historiografía, geología, mineralización, tamaño, forma de estructuras y controles de la mineralización en el yacimiento minero de Antamina, Ancash. En 1850, Leonardo Pflücker fue el primer propietario y operador de Antamina. Posteriormente Vicente Lezamet trabajó en la región hasta 1914 obteniendo matas de cobre de 32%. Es a partir de 1951 que la Cerro de Pasco se interesa por el yacimiento, adquiriendo derechos de propiedad, e iniciándose el proceso de exporación hacia 1953. Con la experiencia y resultados de la primera campaña, se realizó la segunda etapa de exploración, culminándose en 1958. Los minerales más importantes son los granates verdes y marrón-rojizos seguidos de la clorita. La topografía del valle de Antamina es glaciar con valles en forma de "U" y está rodeado de lagunas de 30 hectáreas con una represa natural de roca. De otro lado, Antamina es un ejemplo de "metasomatismo de contacto", donde en los depósitos del mineral, existe un contacto entre un intrusivo y los sedimentos que lo rodean. Existen tres zonas en el área de Antamina: la zona de "Laberinto" situada al lado SE del valle, la zona lamada "Taco" al NW del valle, y "Usupallares" situada a un kilómetro al SW de " Laberinto". De las tres zonas señaladas, la primera, es la más importante puesto que allí están emplazados dos cuerpos mineralizados con leyes comerciales. El principal control de la mineralización son los agregados de cristales de granate, los que a su vez, obedecen a controles que no han sido todavía explicados con claridad. Sin embargo, los pliegues, fracturas y zonas de cizallamiento, constituyen controles importantes. Finalmente, dadas las características de este tipo de yacimiento, el proceso de exploración resulta muy costoso, requiriéndose gran número de labores para encontrar y delinear las zonas mineralizadas.

Jul 20, 1959

By S. McGinn

The Brunswick Mine Diesel Particulate Filter Study was one of several research projects initiated by the Diesel Emissions Evaluation Program (DEEP). The study was carried out at Noranda?s Brunswick Mine in Bathurst, New Brunswick by Noranda Technology Centre and Brunswick Mine personnel with the collaboration of Natural Resources Canada - Canada Centre for Minerals and Energy Technology (CANMET), National Institute of Occupational Safety and Health (NIOSH), Andreas Mayer of VERT, and diesel particulate filter (DPF) system suppliers. The study began in early 2000. Field evaluations continued for 20 months. The final report?authored by Sean McGinn?was submitted to DEEP in the Autumn of 2003.

Jan 1, 2004

By F. F. Hintze

In the group of minerals used in making this study, the cyanite is associated with quartz, mica, and feldspar in the schist. The amount of quartz is variable, but it is always an abundant mineral. Both large and small crystals of quartz occur in irregular masses, rarely ever showing crystal outline. Mica Is of the clear and dark varieties, the larger crystals being dark as a rule, and the finer crystals of light color. The present mineralogical composition of the mina is rather variable, as most of the original biotite and muscovite have suffered alteration, and much secondary mica is present as a result of alteration of the original mica and other minerals present, especially the larger cyanite crystals. A large part of the mica now found in the ore is chlorite, with varying amounts of Jefferisite and others, especially sericite. These are in the form of aggregates, or felt-like intergrowths filling the spaces between the quartz, cyanite, and feldspar. The feldspar is plagioclase probably mostly albite. It is white, possesses good cleavage, and is one of the hard brittle minerals of the rock. It alters to kaolin, and sericite, and more or less of these alteration minerals are present within the feldspar crystals but not separated from them. The cyanite is of two varieties, distinguished by their colors as blue and white cyanite. The blue color varies in intensity, being a pronounced blue in some crystals and paler in shade in others. Some crystals have been seen which posses the blue color in one-half of their mass and are pure white or clear in the other half. The purity of the cyanite is probably not affected by the color, but it is difficult to detect the white cyanite in the ore by macroscopic examination, so that great care has to be exercised in the selection of the ore in the field. Of the above minerals, cyanite is the heaviest, having a specific gravity of 3.6; none of the others approach it in specific gravity. The usual as opiates of cyanite in the mica schists are garnet, magnetite, and tourmaline, but these have not been noted in the group of minerals treated, and their absence is a point of great value in favor of this ore, as they possess high specific gravities and interfere in separation processes, and if not separated they are detrimental because of their easily fusible character. Small amounts of apatite and titanite have been noted, but not enough to cause trouble.

Jan 1, 1931

By Russell Webster

In having maintained production for more than 40 years Arizona's Magma mine is unique in a mineral district that includes several major copper mines. Other past and present producers in this area are Miami and Inspiration at Miami, the Old Dominion in Globe, the Ray mine in Ray, and to the south the new San Manuel mine near Tucson. Magma's production of copper, silver, gold, and some zinc has come from nearly parallel east-west striking mineralized faults, one called the Main or Magma vein and the other the Koerner vein, about 1100 ft to the south. This vein system has been prospected and partially mined for some 9000 ft horizontally and 4800 ft vertically. In ascending order from the deepest exploration level, the Main vein cuts Pre-Cambrian schist, Pre-Cambrian Apache Group, Post-Devonian diabase, and Devonian, Mississippian, and Pennsylvania limestones. Until 1950 very little ore was obtained from replacement mineralization.

Jan 10, 1958

By Douglas R. Shaw

Normal dodecyl mercaptan was evaluated as a collector for flotation of sulfide minerals and precious metals. The reagent is from the class of normal mercaptoalkanes (n-alkyl thiols), and is commercially available in the form of a mixture of n-dodecyl mercaptan and a dispersant, under the trade name Pennfloat(TM)3. Reported are results of bench-scale flotation experiments on many commercially treated base metal and precious metal sulfide ores. Dosages, points of addition, and flotation pH were among the uariables studied. Most notable results were increased copper, molybdenum, and precious metals recoveries. Dosages of dodecyl mercaptan on some ores were considerably lower than required for conventional collectors.

Jan 1, 1979

By K. L. Ford, D. R. Lentz, J. H. Rickard, R. P. Taylor

Abstract - Coupled gamma-ray spectrometric and lithogeochemical studies throughout the Heath Steele Mines area, Bathurst Camp, New Brunswick, indicate that primary and secondary geochemical differences exist between the stratigraphic footwall and hangingwall crystal tuff units which host the massive sulfide deposits. Of particular interest is Th, and to a lesser extent, Zr and Y, which are more concentrated in the hangingwall than the footwall crystal tuffs, whereas the opposite is true for TiO2. This expands on earlier lithogeochemical-chemostratigraphic results concentrated in the eastern part of the Heath Steele belt that led to revision of the local stratigraphy, and necessitated a structural re-interpretation of the area with implications for exploration. Although K depletion (decreased K and K/Th) is typical of chloritized footwall zones of chloritization, these features were not fully apparent here due to the recessive nature of these altered zones. In situ radiometric analysis using a portable gamma-ray spectrometer is a rapid, inexpensive analytical technique for chemostratigraphic characterization of rock units within volcanogenic massive sulfide deposit settings, provided there is a contrast in the distribution of natural radioelements, particularly Th and K.

Jan 1, 1998

By P Wigley

New methods of analysing and modelling flotation circuits have been developed as part of the AMIRA P9 mineral processing research project. A study using these techniques was conducted on the Olympic Dam copper flotation circuit to provide the following outcomes: an estimate of the flotation cell hydrodynamic properties and froth performance characteristics, and identification of potential areas for improvement; an estimate of the feed floatability parameters for basic model development; and identification of potential flotation circuit improvement opportunities. A flotation circuit model of the Olympic Dam copper concentrator was developed using the data collected from mass balanced site surveys, along with hydrodynamic data, froth performance data and numerous laboratory batch flotation tests. The simulator that has been developed from the model has the ability to estimate the influence of selected changes (such as circuit changes) on flotation circuit performance. Several stream destination simulations were conducted to provide guidance for further testwork and possible circuit improvements. The results from these simulations are presented.

Jan 1, 2003

By James A. Morrison, Stephane Carayol, Paul H. Madsen

The Rio Piedras Alignment Section 7 of the Tren Urbano is currently being constructed beneath a historic commercial section of San Juan. Different portions of the section are being constructed using open cut, cut-and-cover, New Austrian Tunneling Method (NATM), Earth Pressure Balance Machine (EPBM), and as tacked drift mined support system. The combination of complex geology, low ground cover, and several innovative construction methods present many challenges to the ground control program. Mining and construction sequences were first developed to minimize ground movements and risk of damage to structures. A unique compensation-grouting program was developed to improve the ground, limit settlement, and recover settlements incurred due to mining.

Jan 1, 1999

By F. H. Seymour

Central to Newmont Gold's Mine planning system is the ability to interactively perform cut and fill operations on topographic contours and to accurately evaluate grades and tonnages within contour outlines using polygon set manipulation routines. This paper develops the applied geometry concepts that underlie these routines. Included are representation of volumes with contours, point in polygon test, block proportion in polygon calculation, polygon area and centroid calculation, and intersection, union, and complement between polygon sets.

Jan 1, 1990