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By W. J. Wenger

Colorado has been producing petroleum since 1863 but only recently has become a major oil State. The first well was drilled on Oil Creek near Florence, but out-put was relatively small until discovery and development of the Weber sandstone reservoir at Rangely. Oil was discovered in the Weber sandstone in 1933, and the reservoir was developed after 1940, bringing Colorado, in 1949, to 11th place among the 48 States as an oil producer. Colorado's output increased further because of the discovery and development of many fields in the Julesburg Basin since 1949 By 1954 Colorado was in ninth place and maintained that position through 1955.4/ Between 1946 and 1951, Colorado's oil production more than doubled, while the total United States production increased only 25 percent. It seems probable that production will continue to expand in Colorado for many years. This report presents analyses of 92 crude oils from 73 fields representing 90 percent of the production in 1955. Abridged analyses are listed for easy comparision, and complete analyses arc given in the appendix. Oil samples were collected for study from many different sources. Although many of the newer fields were not sampled, their oils probably are very similar to those from corresponding formations that were studied and tabulated.

Jan 1, 1957

By L. F. Ruppert, W. D. Watson, S. J. Tewalt, L. J. Bragg

The U.S. Geological Survey recently completed a digital coal resource assessment model of the Upper Pennsylvanian Pittsburgh coal bed which indicates that of the original 34 billion short tons [31 billion tonnes] of coal, 16 billion short tons [14 billion tonnes] remain after subtracting mined-out coal. When technical, environmental, and social restrictions are applied to the remaining Pittsburgh coal model, only12 billion short tons [11 billion tonnes] are available for mining. Our assessment models estimate that up to 0.61 billion short tons [0.55 billion tonnes], 2.7billion short tons [2.4 billion tonnes], and 8.5 billion short tons [7.7 billion tonnes] could be available for surface mining, continuous mining, and longwall mining, respectively. This analysis is an example of a second-generation regional coal availability study designed to model recoverability characteristics for all the major coal beds in the U.S.

Jan 1, 2000

By H. J. de Haan, L. Schenk

Scope for Thermal Recovery in Shell's Heavy Oil Fields in Venezuela The main heavy oil reservoirs on the East coast of Lake Maracaibo (Fig. I), known as "Bolivar Coast", initially contained some 20 billion bbl of oil in place with gravities in the range of 10 to 15° API. The current total production rate is about 400,000 B/D. Since the recovery to date is on an average only 12.5 percent of the initial oil in place, these fields offer a vast potential for secondary recovery methods. The reservoirs are characterized by moderate depth (generally 1,000 to 3,000 ft; maximum 5,000 ft), good formation properties such as net oil sand thickness (50 to 300 ft), high porosity (30 to 40 percent) permeability (1 to 3 darcies) and oil saturation (initially about 80 percent) and high oil viscosity (100 to 10,000 cp in situ), all of which are favorable for the application of thermal recovery processes. Since 1957, steam drive, steam "soak" and underground combustion have been tested or are being tested in this area.1-3 This paper deals with a major steam drive test in the Tia Juana field. The test was commenced in Sept., 1961, on the basis of encouraging results of laboratory experiments and pilot field tests, which will be discussed briefly. Early Laboratory Investigation of the Steam Drive Process In 1956 a series of model experiments was carried out in the Koninklijke/Shell Laboratorium, Amster- dam, to investigate the displacement of heavy oil by steam.' The prototype studied was a horizontal, un-consolidated heavy oil reservoir, subjected to a linear steam drive. The model, representing a slab from this reservoir along the main flow direction, consisted of a steel tube filled with oil-saturated sand, provided with layers of rock at the top and bottom to simulate conductive heat losses to cap and base rock. Lateral heat losses, perpendicular to the main flow direction, were minimized by insulating the sides of the model. Heat flow and viscosity and gravity forces were scaled by taking the steam injection rate and sand permeability inversely proportional to the geometric reduction factor of the model, and using materials (oil, steam, cap rock, etc.) identical with those of the prototype. The main feature of the process was a frontal displacement mechanism that was observed within wide ranges of injection pressure and rate, oil viscosity, initial oil saturation and sand permeability. The high stability of this front can be attributed to the high volumetric steam flow rates, combined with the reduction in oil viscosity. High recoveries were obtained due to the low residual oil saturation of about 15 percent in the zone swept by steam. The latter value pertains to the specific test conditions (heavy oil, uncon-solidated sand) and may be lower for light oil, due to the effects of steam distillation. The applicability of this experimental approach is limited, as it does not take into account the fact that

Jan 1, 1970

The Geological Resource Map of New Zealand (GERM) is a computerised inventory of aggregate, mineral, coal, petroleum and thermal water occurrences, containing summary information on location, production, geology, and geochemistry. The types of occurrences include quarries, mines, gold dredges, wells, outcrops, seeps, springs, and fields. The file contains entries for about 10,300 sites and is used to produce tables of data and maps at any scale, for single or multiple commodities. The published format is the New Zealand 'Geological Survey map series Geological Resource Map of New Zealand 1:250 000'. Seventeen of the 27 map sheets covering New Zealand were published by August 1991, with three more close to publication.

Jan 1, 1991

By S McGregor, J Sharp, I Entezari, T Boulter

The piezocone penetration test (CPTu) is one of the primary screening tools used by the mining industry to evaluate whether tailings are susceptible to liquefaction (static or cyclic). Liquefaction analysis using the CPTu is influenced by the fines content of the soil, and most CPT screening tools empirically use the behaviour type index (Ic) to correct for fines. The issue with this approach is that such empirical relationships have been developed using data collected from natural soils and their applicability to different tailings deposits needs to be studied. In this paper, we explore the use of machine learning to develop a site-specific model to estimate fines content of tailings using gamma piezocone penetration testing (GCPTu) measurements. The results are then compared to the fines content derived from the soil behavior type index (Ic) proposed by Robertson and Wride (1998). A dataset of paired GCPTu and laboratory results were compiled and a support vector machine (SVM) algorithm was employed to calibrate a model to estimate tailings fines content from in-situ GCPTu data. We calibrated GCPTu data to geotechnical 75 μm fines content measured in the laboratory. The geotechnical fines content is the fines content as a percentage of solids. The development dataset was comprised of paired GCPTu-laboratory results collected in 2009-2019 from a mining area with predominately clay mineral and quartz sand tailings. Results show that the developed model predicts the geotechnical 75 μm fines content of the studied deposits with 7.8% error. The Ic based method estimates the fines content with 31% error. Evidently, the Ic method is not applicable to the studied tailings deposits. It is appreciated that many tailings fines do not contain clay, and that the success on this program may not be repeatable everywhere. However, the authors wish to point out that the application of site-specific machine learning algorithms may be used to significantly improve empirical geotechnical parameters.

Jul 1, 2021

Queensland?s underground coal industry, as a whole, has arguably the best gas monitoring systems in the world. Each mine utilizes real time, tube bundle and onsite ultra fast gas chromatograph systems. Queensland?s mining legislation has specific requirements for mine gas monitoring but there is no requirement for all three techniques. Industry has however identified the need for all three and adopted this as a standard, resulting in over sixty thousand gas results collected each day. Automated monitoring systems are programmed to alarm for gas concentrations, gas ratios and explosibility. These alarms are then used to initiate predetermined actions to take control of the situation and prevent the compromise of safety to workers and the loss of resources. Dedicated software packages have been developed to assist in the interpretation of the large volume of results generated. The real time systems are used for real time warning, essential for incidents such as belt fires. Tube bundle systems suit long term trending used for identification of the onset of spontaneous combustion or for the determination of explosibility during the routine sealing of worked areas. Gas chromatograph analysis is used to provide a complete analysis and provides results for hydrogen and ethylene, key gases used in the assessment of spontaneous combustion. It is also crucial during significant spontaneous combustion events and coal fires to use gas chromatography to determine the explosibility status of the underground atmosphere otherwise the severity of the situation is likely to be under estimated. This paper outlines the need for all three techniques for assessing the underground status and outlines advantages and disadvantages of each.

Jan 1, 2009

By Michael Young, Josh Rubenstein, Michael Cooper, Tom Shouldice, Dan Curry

"Xstrata Nickel Australasia’s Cosmos plant in Western Australia is currently implementing a debottlenecking project to increase nickel output while maintaining metallurgical performance and a low unit cost for production. Mineralogical analyses indicated that the processing bottlenecks could be removed by simply reconfiguring portions of the circuit as well as adding capacity with technical advancements – notably an IsaMill™, Jameson Cell, Wemco® SmartCell™ and Larox Filter.The Wemco® SmartCell™, which is particularly suited for coarse mineral flotation, and Jameson Cell, which is particularly well suited for fast floating and fine minerals, combine as rougher scalpers to complete the main stream portion of the flotation circuit. Addition of the two new cells meet the required flotation capacity to handle the forecast increase in nickel feed grade and tonnage.The addition of an IsaMill™ for regrinding allows the SAG mill to produce a coarser primary product, thus enabling increased throughput. The advantages offered by the IsaMill™ include operation in open circuit (internal classification), an inert grinding environment (ceramic media) for better downstream flotation (“clean” new surfaces), compact footprint (easy to retrofit into existing plant) and energy efficiency. With the new rougher capacity addition, the remaining original plant cells were reconfigured to suit the new regrind mill and cleaning requirements. The existing 24 m2 Larox pressure filter was replaced with a larger 32 m2 unit to dewater the increased concentrate output.The paper describes the upgrade at the Cosmos concentrator with particular emphasis on the mineralogical data and metallurgical benefits associated with the changes.INTRODUCTIONThe Cosmos concentrator is located 680 km northeast of Perth in Western Australia. The deposit’s development and operations were started in 1999 by Jubilee Mines NL, Cosmos’ previous owner, with the first production of nickel concentrate in April 2000. The Cosmos concentrator treats a komatiite hosted high grade nickel sulphide ore, with sulphides being predominantly pentlandite and pyrrhotite with lesser amounts of pyrite and chalcopyrite."

Jan 1, 2010

By P. Turcotte, E. Karampinos, F. Mercier-Langevin

In some underground hard-rock mines, squeezing compressive ground conditions are influenced by the presence of rock foliation and high stress. In these cases, the orientation of the foliation with respect to the drift direction has a considerable impact on the magnitude of the resulting deformation. Irrespective of the reinforcement and support strategy, keeping drives developed sub-parallel to the rock foliation operational is difficult, and often requires excessive rehabilitation during the lifetime of the excavation. This study uses field observations and convergence measurements at the LaRonde and Lapa mines of Agnico Eagle Mines Ltd to provide guidelines of the anticipated squeezing levels at these operations.

Jan 1, 2015

By P. Fauvel, V. Nasri

In January 2001, French and Italian governments signed an agreement for the construction of a new Lyon-Turin railway line. This project includes a tunnel of 53.1 km length and a maximum of 2500 m overburden to be designed for a reference speed of220 km/h. The tunnel crosses major part of the West Alpine geological formations, which are very complex and contrasted in terms of the nature of rocks and the mechanical and hydrogeological conditions. In addition to the twin single-track tubes, numerous intermediary shafts, security station and intervention sites and cross passages should be built to respond to the security, operational and construction requirements. This paper describes the results of the preliminary engineering design and multiple challenges of this very long and deep railway tunnel.

Jan 1, 2005

The corrosion of aluminosilicate refractories by soda from three different sources has been studied by microscopic methods. Sodium sulphate from oil ash, sodium chloride used in glazing structural clay products, and sodium borate from borax-impregnated wood ash have fundamentally the same effect on the refractories. The soda is the chief medium of reaction and fluxing, the sulphur, chlorine, and boron being volatized as sulphuric, hydrochloric, and boric acids.INTRODUCTIONBecause of their strong fluxing action, alkalis are one of the main causes of corrosion and slagging of refractories.The action of potash and soda on refractories follows somewhat similar lines, although it is common for one alkali to be greatly in excess of the other. The course of the reaction in a number of cases of alkali attack has been studied by microscopic and chemical methods. For example, the action of potash on blast furnace refractories was studied by Kraner (1942) and Rigby and Richardson (1947), who described the occurrence of various potassium aluminium silicates. Its action on cement kiln refractories was described by Brisbane, Segnit, and Weymouth (1957). The action of soda on glass tank refractories has been studied by many people, for example Bisby (1956) and Resch (1954). Clews, Hugill, and Green (1940) made a microscopic examination of the attack by soda on silica bricks from a gas retort.Some recent cases of corrosion of aluminosilicate refractories which were brought to the attention of the Division of Building Research, C.S.I.R.O., illustrate phenomena which occur under conditions different from those...

Jan 1, 1964

By D Pilone

The Tyrrhenian micro-nodules, findable at low depths (200/600 m under s l) are a reasonable reserve of manganese. They can be easily and cheaply recovered but do not contain valuable metals as in the case of oceanic nodules. In this work a hydrometallurgical process for manganese recovery from Tyrrhenian nodules is presented. The studied treatment includes the following operations: magnetic enrichment, reducing leaching, leach liquor purification and electrowinning . The study shows that the most important step in the process is the preliminary manganese enrichment. It can be done directly on the platform reducing not only the transport cost, but also the residue mud in the metallurgical plant. The leaching parameters such as status and size of nodules, temperature, composition of leaching solution and S/L ratio have been investigated. After purifying the leach liquor by iron precipitation as ammonium jarosite , the conditions to electrowin manganese have been investigated. The yields of both manganese leaching and iron precipitation together with current efficiency and specific energy consumption in the electrowinning step are given.

Jan 1, 2000

By David C. Girard, Larry Williamson, Leonard R. Benson, Ronald E. Bizzarri

On the east side of Washington DC, the DC Water & Sewer Authority is developing a Facility Plan for the Anacostia River CSO Control Projects, including 8 to 12 miles of CSO storage/conveyance and flood relief tunnels and associated facilities. The project includes major technical and non-technical challenges, including: completion under a Federal Consent Decree schedule; large diameter (estimated 25 to 35 ft) soft ground tunnels and shafts up to 200 ft depth; operations without use of active flow control systems; and close coordination with several major public and private construction and development projects that are being advanced in the project area.

Jan 1, 2007

By Z. J. Hladysz

A Deep Underground Science and Engineering Laboratory (DUSEL) is being planned at the site of the former Homestake Gold Mine in Lead, South Dakota, under the sponsorship of the National Science Foundation (NSF) in cooperation with the Department of Energy (DOE). This national facility will host a variety of multi-disciplinary science and engineering experiments including physics experiments that require shielding from cosmogenic radiation. Current plans include construction of large rooms (up to 55 m in width) at depths of 1.48 km (4850 ft) and 2.25 km (7400 ft) below the surface. Preparation of the preliminary design required the development of a geotechnical characterization program including: preliminary drilling and coring, core logging, drill hole mapping with a televiewer, drift mapping of the geology and rock structure, in-situ stress measurements, and laboratory testing of the mechanical properties of the rocks and discontinuities. Overall rock quality is very good to excellent. Site investigations were followed by geotechnical assessments for the construction of caverns and laboratory modules. The results are favorable and reaffirm selection of the Homestake site for establishment of a Deep Underground Engineering and Science Laboratory.

Jan 1, 2011

By P. den Hoed, R. I. Rambiyana

"Four sulphide minerals - pyrite (FeS2), pyrrhotite (Fe1-xS), pentlandite ([Ni,Fe]9S8), and chalcopyrite (CuFeS2) - contain the base metals and most of the iron in concentrates of platinum group metals (PGMs). In the pyrometallurgical processing of PGM concentrates these sulphides form a matte during smelting, and iron and sulphur are removed from the matte during the converting process. This paper discusses the roasting of Merensky concentrate in air before smelting, with the purpose of reducing the matte load to the converter.Roasting tests were conducted in a bench-scale rotary kiln at temperatures from 350°C to 700°C. The concentrate tested contained 17.4% sulphur and consisted of 23% pyrrhotite, 16% pentlandite, 11% chalcopyrite, and 2% pyrite. The particles were fine (d50 = 22 µm), and all the sulphide particles were liberated. Roasting in air at 550°C and 650°C for 20 minutes removed respectively 60% and 70% of the sulphur. The iron in the sulphides was oxidized to Fe3O4 (magnetite) at temperatures below 500°C and to Fe2O3 (haematite) at temperatures above 550°C. At 700°C the bed sintered and copper oxides formed. At temperatures below 450°C oxidation was incomplete: pyrrhotite remained and only 30% of the sulphur was removed. Smelting tests were conducted to assess matte fall and the deportment of copper and nickel to matte. It was evident that roasting resulted in lower matte falls (a drop of approximately 60%) compared with matte falls from unroasted concentrate. The iron and sulphur levels in the matte were reduced to below 3.5% and 22% respectively.This paper also briefly describes the mechanisms by which pyrrhotite, chalcopyrite, and pentlandite are oxidized during roasting. For chalcopyrite, the mechanism proceeds through an intermediate solid solution phase, which extends from Cu1.02Fe1.04S2 to Cu2.04Fe0.72S2 to a copper-rich solid solution of bornite (Cu4Fe1.4S4-Cu2S). The oxidation of pentlandite proceeds through a monosulphide solid solution (Ni0.39Fe0.53S-Ni0.74Fe0.15S) to a solid solution of heazlewoodite ([Ni,Fe]3}xS2). These mechanisms are explored in relation to chemical thermodynamics and microstructures."

Jan 1, 2015

By David A. Hill, James R. Wait

This report contains a summary of analytical research on electromagnetic methods of nondestructive testing of cylindrical conductors. The principal objective is to provide theoretical insight to the operation of electromagnetic sensing of the internal properties of wire ropes that are used extensively in mine hoists. An overall review of past work is also included.

By J. W. Bridge

Triaxial compression tests at various confining pressures and temperatures, as well as tangent modulus tests using ultrasonic waves, were conducted for wax-coated granular composite materials. The material used is a surface for Thoroughbred horse racing. The purpose of these tests is to examine how track shear strength and tangent modulus at a range of loads respond to changing temperatures. Previous work has shown that a wide range of operational temperatures are experienced which have been reproduced in the lab. Using differential scanning calorimetry, it is confirmed that these operational temperatures correspond to distinct thermal transition regions for the wax that is used to coat the sand in these surfaces. Preliminary results show that both shear strength and tangent modulus are sensitive to temperature changes with maximum strength and modulus correlating with major DSC wax transition regions.

Jan 1, 2010

By A. Amiel

Tarkwa Gold Mine is owned by Gold Fields Ghana, IAMGOLD and the Government of the Republic of Ghana in a 71%, 19% and 10% ratio. The mine is operated by Gold Fields Ghana. This large, low-grade, open pit, gold mining operation is located in Tarkwa, in the Western Region of Ghana, approximately 320 kilometres by road, west of Accra, the capital of Ghana, West Africa. In the Financial year ended June 2007, the operation mined a total of 108 million tons of which 22 million tons was ore. The mined ore is processed through three gyratory crushers supplying two heap leach pads (north and south) and a carbon-in-leach (CIL) plant. Before the 6 Sigma project commenced, the current fragmentation was resulting in sub-optimal feed size to these crushers. It was decided to use 6 Sigma methodology to improve the fragmentation. A defect was defined as a fragmentation analysis indicating less than 95% passing 750 mm. The objective was to improve fragmentation in order to achieve a constant throughput to the north heap leach crusher of 1500 t/h, a 5% increase in pit loading efficiency and a 50% decrease in rock breaker hours, equipment damage costs and in-pit sheeting costs respectively. However, this was not to be achieved at the expense of grade control as Tarkwa is exploiting a low grade, high volume deposit and therefore ore dilution must be kept to a minimum. This paper is intended to take the reader through the various 6 Sigma phases of the project (define?measure?analyse ?improve?control), which have resulted in a 10% reduction in loading times, of which half has been attributed to improved fragmentation, as well as a substantial increase in blasted stocks. The focus has been on both drilling and blasting parameters as both processes had to be taken into account. These parameters are technical but personnel factors were also identified and dealt with as they arose. In order to measure the impact of any change in the process parameters on the fragmentation size distribution, cameras have been acquired. One has been installed looking into the bowl of the north crusher and the other one was dedicated to field observation, of individual blasts. Both are used for ongoing fragmentation analysis. At Tarkwa, mining efficiency is strongly dependent on good fragmentation as well as the presence of unblasted ?toes? on the pit floors. Crusher throughput depends on an acceptable ore fragment size. Compliance with plan for actual hole depths was temporarily monitored by manual hole dipping, but this is now being replaced with a fully automated drill data management system developed by Sandvik and Modular Mining. The Six Sigma methodologies, using control charts based on data collected in the field, allowed the mine to improve methods for the control of blasted material. It also enforced the implementation of a quality control programme encompassing the entire drill and blast process.

Jan 1, 2008

By J. M. A. Geldenhuis

This work is concerned with studying possible reactions in the ilmenite furnace which may control the product quality of both slag and metal. Two different approaches were followed: comparing actual furnace slag compositions with the calculated equilibrium values and using commercial oxygen probes to measure the effective partial oxygen pressure in the slag and metal. It appears from a comparison of actual furnace slag compositions (in terms of the distribution coefficient of vanadium) with equilibrium values, that the TiO1.5-TiO2reaction may fix the effective partial oxygen pressure for the vanadium reaction. This possibility was tested using commercial oxygen probes (traditionally applied during steelmaking) to measure the effective oxygen partial pressure of both the slag and liquid iron in Iscor?s 3MVA pilot plant ilmenite furnace. From these measurements, it appears that commercial oxygen probes containing zirconia solid electrolytes can be used to measure the effective oxygen potential of both the slag and liquid iron. This oxygen activity correlates well with the FeO content of the slag. The results, furthermore, clearly illustrate that equilibrium conditions are not attained in the ilmenite furnace during the production of high titania slags, since the effective oxygen potential of slag and metal differ substantially.

Jan 1, 1999

This volume contains a series of papers describing research conducted by the Bureau of Mines to develop or improve equipment and systems that satisfy the communication requirements of miners doing work related to rail, belt-conveyor, trackless, and hoist haulage systems.

Jan 1, 1977

By D Craw, S Clearwater, S Hammit, C Smith

Prior to rehabilitation, plant cover on quartz gravel overburden at Wangaloa coal mine was highly patchy. Stabilisation techniques have since considerably altered the condition of the main overburden yet deposits in the east and west remain largely intact. On the eastern overburden, three distinct zones of revegetation have naturally developed: Zone 1 represents a dense plant cover, Zone 2 a patchy cover and Zone 3 a sparse cover of isolated plants. Aerial photographs show much of the eastern overburden was deposited between 1940 and 1960s. Yet we found that the temporal scale of deposition did not wholly account for the differences observed in vegetation development. To investigate other influential factors, we set up 12 study plots using four replicates in each vegetation zone. The diversity and density of plants in each plot were measured to quantify the degree of vegetation development. Samples from the substrate in each plot were collected using soil cores to a depth of 10 cm. Cores were analysed for indicators of nutrient availability, metal content and physical composition. We found that substrate chemistry varied between individual study plots, but showed little difference overall along the vegetation gradient. Substrate physical differences were much greater. The ratio of coarse quartz pebbles: fines was considerably higher in Zone 3 than other zones, and within zones where plants were not growing. Bulk density also increased successively from Zone 1 - 3. We found clear evidence for the reversed stratigraphy of excavation superimposed over the time scale of deposition, and the corresponding nature of fine particles. The rate of revegetation was therefore highly dependent upon the substrate composition of the last surface deposit from the dumping truck. Our data suggests an optimum ratio exists between inert coarse material and a fine matrix for progressive natural vegetation development on mine substrates.

Jan 1, 2004