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Iron ore in the Middleback Range area has a density and susceptibility contrast with adjacent rocks, and gravity and magnetic methods are applicable to exploration for it. The gravity method is satisfactory whether the ore mineral is hematite, magnetite, or limonite; the magnetic method is suitable for detecting ores which contain magnetite, such as some hematite ore, magnetite ore, and possible ore in the form of magnetite-bearing schists. jaspilites, and carbonate rocks.Geophysical exploration began in 1948 and is still in progress. The methods which have been used are aeromagnetic (83 per cent), ground magnetic (13 per cent), gravity (3 per cent), and others (1 per cent). Ground magnetic surveys have been made wherever aeromagnetic surveys recorded large anomalies. The gravity method is being used to investigate those parts of the area considered most favourable for ore occurrence.Qualitative and quantitative interpretation of the geophysical data has been made and the rocks causing selected anomalies tested by bores.Magnetite in the Middleback Group rocks produces the major magnetic anomalies in the area. The average magnetite content of magnetite-jaspilite, which is the commonest rock type, is 33 per cent by weight and that of magnetite-carbonate at the Iron Duke-Iron Duchess is 50 per cent. These rock types also contain hematite and the average total iron content of the former is 35 per cent and of the latter 50 per cent.INTRODUCTIONThe geology and iron ore resources of the Middleback Range area were described by Miles (1954). Since 1954, much drilling, mapping, and quarrying has been done but there is no published report of this work.The rocks which constitute the Middleback Range, Camel Hill-Cooyerdoo line, Katunga Hill-Iron Knob, and Ash Range (Fig. 1) belong to the Middleback Group of Middle Precambrian or late Archaean age. Most outcrops of the Group are jaspilites, formerly called banded hematite (or magnetite) quartzite. The high grade hematite deposits...

Jan 1, 1964

By S. Hoskins, S. Chiovelli

"The annual budget for the repair and maintenance of equipment at Syncrude Canada Ltd. is in excess of $450 million. Of this amount, a significant portion can be attributed to the loss of material on various pieces of equipment throughout the operation. In order to effectively battle the different wear and corrosion mechanisms that lead to material loss, it is important to understand how materials behave in the environments in which they are used. Through the work carried out at Syncrude, and work conducted with various external collaborators, significant improvements in both equipment reliability and productivity have been achieved. This paper will review some recent field trials where materials research has demonstrated the potential for significant improvements in equipment run life and reduced maintenance costs. These field trials will demonstrate the need for understanding the interaction between various damage mechanisms and the materials used in different services. The paper will also discuss current areas of focus along with future directions for further work. IntroductionSyncrude Canada Ltd, located in northern Alberta, Canada, operates a mining, extraction, and upgrading facility that removes bitumen from oil sand to produce synthetic crude oil. Oil sand is mined from the orebody using conventional open pit mining techniques. Recently, the mining scheme has changed from a dragline/bucketwheel/conveyor system to a shovel/truck/crusher/hydrotransport operation as depicted in Figure 1. Since the start of production in 1978, the identification, development and application of wear protection has been an ongoing challenge due to the abrasive nature of the oil sands and the massive volumes of materials that are moved. The use of various materials and application processes along with component design modifications has resulted in significant improvements in both productivity and reliability (Adamic et al., 1995; Llewellyn, 1996, 1997; Anderson et al., 1998; Chiovelli et al., 1998).In an effort to continuously improve the operation, Syncrude has been quick to adopt new wear technologies. As seen in Figure 2, since the start of operation, a variety of materials have been used to increase wear performance and ultimately equipment reliability and availability. Although Figure 2 does not show a time axis, the bottom axis may also be used to represent a time progression for the predominate use of these materials at Syncrude. Tungsten carbide metal matrix composite (WC-MMC) overlays are currently the materials of choice for most of Syncrude’s critical production applications. Metal matrix composite overlay technology has potential for significant improvements and Syncrude is actively working with powder consumable manufacturers to advance this technology."

Jan 1, 2004

By Moresby J. F

Segregation roasting was used to recover more than 85 per cent of copper from crushed, minus 14 mesh refractory furnace-lining bricks. A plus 14 mesh fraction: which was high in copper, could be recycled directly to the smelter, giving an overall recovery of approximately 90 per cent. An oxidation roast at about 700°C was necessary, before segregation roasting, to convert copper sulphides and copper metal to sulphates and oxides. Withsegregatron temperatures in the range 600°-650°C the quantities of solid carbon and NaCI required are 2-5 per cent and 1 per cent respectively. P.V.C. coating from scrap copper wire can be used instead of NaCl as asource of hydrogen chloride for the segregation reaction.

Jan 1, 1978

By G. T. Engel, W. G. Gruzensky

Jan 1, 1960

By R. G. Fleck, W. R. Webb

Iron ore mining in the Adirondack region of northern New York dates back to the Revolutionary War. It is recorded that Benedict Arnold in his campaigns in the Lake Champlain area during the American Revolution utilized the local ores to produce armament and cannon balls. Through the efforts of early pioneers, the iron mining industry in northern New York gained impetus so that in the 1880's mines in the area accounted for nearly one fourth of the iron ore produced in the United States. Both magnetite and red hematite ores were mined during this period. With the discovery of the Lake Superior ores, the iron ore industry in New York started to decline and remained relatively unimportant until 1938. Modern day methods of mining and beneficiating sufficiently high tonnages of low-grade ores to justify the large expenditures for plant and equipment prompted a resurgence in northern New York mining. During the past several years, the production of iron ore from the Adirondack magnetites has greatly increased, and production which amounted to .6%, of the United States total during the 1918-1928 period (Mining and Metallurgy, November 1943) has been increased to 2.85% of the total in 1948. Today, Republic Steel is mining in the Port Henry-Mineville and Lyon Mountain areas; the

Jan 4, 1950

By Ron Frye, Carl Liibbe, Wayne Curtis, Julie Pecori, Dan Leach

Test work comparing the performance of a Low Density Porous Ammonium Nitrate Prill to regular Porous Ammonium Nitrate conducted in Pennsylvania and New York showed that less ammonium nitrate was required to perform the same work and that improved sensitization of an emulsion/ammonium nitrate blend reduced “orange fumes”. Fragmentation was similar in all tests with improved heave and throw experienced.

Jan 1, 1997

By J. R. Thoenen

The enormous and constantly increasing demand for limestone to supply a multitude of uses is a remarkable feature of the mineral industries. As approximately 130,000,000 tons of limestone are produced annually, it is not surprising that deposits at or near the surface are gradually being exhausted and that less advantageous supplies are being worked. Quarries are becoming deeper and wider year by year, and in many places the volume of overburden that must be removed to allow open-pit work has increased alarmingly. Quarrymen are also gradually learning how expensive it is to sort and clean stone from a deposit overlain by poor material. As such conditions confront the limestone industry, the natural tendency is to seek some modification in method whereby the handicaps of increasing cost may be met and overcome. Operators, some of them unwillingly, have been forced to conclude that underground work in drifts and tunnels is the most logical solution of the problem. The unwillingness of some is largely due to unfamiliarity with mining and to the unfounded fear that costs must increase and dangers multiply when mining is undertaken.

Jan 1, 1926

By Robert A. Field

Static-Load Piledriving systems utilize hydraulic push to advance piles into the ground. Dynamic systems (ie. hammers and vibratory equipment) utilize impact, or vibration, to advance the piles. Static-Load systems are most commonly utilized in situations where noise or vibration would adversely affect the people, structures or equipment located near the site. Static-Load technology is most advantageous in situations where vibration, noise or access constraints make it difficult, risky or disruptive to utilize conventional piledriving systems.

Jan 1, 1995

By R. K. Linn

The New Idria Mining and Chemical Co. owns and operates the New Idria mine in southern San Benito County, Calif. During 1957-59, the New Idria mine was the largest producer of mercury in the United States and its alltime production of over a half-million flasks was exceeded only by one mine. It is one of the oldest and most consistent producers in California. With the exception of 1921-22, the mine has an annual production of mercury dating back to 1854. This paper by the Federal Bureau of Mines describes the exploration, development, mining, and furnacing of mercury ore at the New Idria mine. Figure 1 is a view of the furnace plant of the New Idria mine. The purpose of this report is to promote the development and conservation of our mineral resources by dissemination of technological information on mining and processing procedures, and related practices at operating mines.

Jan 1, 1961

By C De-Vitry

"The large Yandi channel iron deposit (CID) is located in the north-west of Western Australia and is currently mined via open pit methods. Drilling at Yandi is widely spaced and current estimates are mostly linear averages of the surrounding local samples. Linear estimates such as ordinary kriging (OK) based on block sizes that are significantly smaller than the dimensions of the drilling grid are less variable than the unknown reality (Armstrong and Champigny, 1989).Conditional simulation (CS) provides a series of plausible realisations that represent the actual grade variability at a small scale (eg 1 m + 1 m + 1 m). These simulations are very useful for a number of purposes, eg: optimising grade control, stockpiling and blending selection of optimal drill hole spacing assessing resource risk on contained tonnage and metal.At Yandi the major constituents of the ore (Fe, P2O5, SiO2, Al2O3 and LOI) are correlated to varying degrees. Independent CS of each assay variable will not reproduce these correlations. Reproducing the correlations (and the shape of scatterplots) is important if the simulations are used for the abovementioned purposes. This paper examines and compares various methods of CS that aim to reproduce the correlations between the assay variables.The CS methods evaluated in this paper are conditional co-simulation (CCS) using the linear model of co-regionalisation and two other, alternative multivariate simulation methods, which use min/max autocorrelation factors (MAF) or the stepwise conditional transform (SCT) to de-correlate assay variables before performing independent CS. It was found that CCS best reproduced the characteristics (histograms, variogram, scatterplots, etc) of the declustered drill hole data (Figure 1). Whilst simulation using MAF generally produced acceptable results, the method did not adequately reproduce the variance of the assay variables. The univariate statistics, histograms and experimental variograms were acceptable for simulations generated from the SCT. Bivariate statistics, cross-variograms and scatterplot reproduction for the SCT were unacceptable. The latter method produced inferior results because there were insufficient samples to obtain a reliable transform of the third assay variable in the transformation sequence.None of the abovementioned simulation methods provides good reproduction of all the scatterplots. This is due to the presence of clay pods, which cause some scatterplots to display two trends. These clay pods contain higher percentages of SiO2 and Al2O3 than the surrounding CID. The clay pods are generally smaller than the drill-grid dimensions. Thus their locations are typically unknown and they cannot be defined by manual interpretation, eg via wireframes. The locations of the clay pods were simulated via indicator CS. CCS was then performed separately for the clay pods and the CID. This significantly improved the reproduction of the correlation coefficients, the scatterplots and visually the simulation was more geologically realistic. Simulating the location of clay pods followed by CCS of assay variables is the recommended approach for simulation at the Yandi CID.CITATION:De-Vitry, C, 2013. Simulation of correlated assay variables - a case study from the Yandi Channel iron deposit, in Proceedings Iron Ore 2013, pp 137-148 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Aug 12, 2013

By Madgwick J. C

Four manganese dioxide leaching microorganisms, an Achromobacter spp, Aspergillus niger, Elllerobacter cloacae and Elllerobacter agglomerails were purified from sucrose enriched crude mixed cultures which contained at least sixteen, non-leaching, morphologically different, colony types. Fastest leaching rates were obtained from the original enrichment's mixed cultures (1.26 g Mn++ I/d) while best yields of Mn++ m terms of sugar use came from Achromobacter and A. niger being 0.84 and 0.89 g Mn++/g sucrose respectively. The peak efficiency in manganese reduced, per carbohydrate used, coincided with the exponential growth phase for Achromobacter. The two Elllerobacter species performed better in stationary or senescent growth phases.

Jan 1, 1985

By Martin B. Hudson, Daniel Brescia, Zhangwei Ning

Due to the complexity and sensitivity of surrounding environments, instrumentation and monitoring (I&M) is critical for many urban deep excavations. The objects to be monitored include shoring bulkheads, retained embankments, adjacent buildings and roads as well as underground utilities. However, there are also plenty of constraints on the implementation of I&M such as: congested site space, difficult access to instruments, coordination among multiple contractors, and installation permits for private or public properties. Because of these constraints, sometimes the implementation of the initially planned I&M is delayed, its scope is reduced, and/or the continuity of monitoring is interrupted. For these reasons, it is important to implement the I&M with robust and redundant capabilities while providing minimal interference to the project construction and schedule. This paper describes state-of-the-art I&M technologies including automatic motorized total station (AMTS) with camera and automatic leveling device, reflectorless AMTS and IoT- based wireless sensors based on a case study of an on-going deep excavation project. INTRODUCTION In urban environments, deep excavations requiring the construction of temporary shoring bulkheads are becoming increasingly common, with the associated need to provide protection of the surrounding built environment during construction. Protection of the surrounding environment requires planning, engineering, construction, monitoring, and excessive shoring movement mitigation. The I&M is a vital component of the deep shoring implementation. In public projects, geotechnical I&M is often placed within the general contractor’s scope, whereas the majority of deep excavations are privately undertaken. For those private developments, sometimes the developer contracts the geotechnical I&M directly with the project geotechnical engineer or by a geotechnical I&M specialist hired by the project geotechnical engineer. In either the public project or private development case, the effective deployment of the I&M system relies heavily on coordination and collaboration with the project contractor.

Jan 1, 2018

By Xiaowen Liu

The DSC/TG, IR and XRD analysis were used to characterize the heating phase transformation of illite, which came from Ouhai deposit, China. It was discovered that the dehydration and de-hydroxylation of illite carried out stage by stage during heating. The adsorptive water and layer-inter water were dehydrated from room temperature to 500°C; and dehydroxylated in the range 500°C~800°C. In these stages of process, illite?s layer structure kept almost unchanged. After 800°Cillite began to change into disorder structure. At about 1100°C, the layer structure of illite had been destroyed, and amorphous SiO2 and mullite crystallite appeared. At about 1200°C the structure of illite completely destroyed and mullite crystal phase had become perfect..

Jan 1, 2006

By Philip Bonanno

The first major project in Boston's new access to Logan Airport was an Immersed Tube Tunnel which extended 3,600 ft. from South Boston to East Boston across Boston Harbor. Twelve tube sections, 300 ft. long x 80 ft. wide x 40 ft. high, were lowered into an excavated trench which was then backfilled. The depth of the trench at mid-channel was approximately 100 ft. below mean high tide. At the East Boston end the tube terminated close to the present shoreline. At the South Boston end the tube terminated approximately 600 ft. inland from the shore line where a ventilation building was required. The depth to subgrade from existing ground at the ventilation structure was approximately 85 ft. The soil profile at this location consisted of 50 ft. of miscellaneous rubble fill, 25 ft. of Boston blue clay, and 10 ft. of glacial till. A small amount of weathered argellite existed at the north end of the structure. Part of the Morrison Knudsen, Interbeton, J.F. White, Joint Venture contract to construct the Immersed Tube Tunnel (ITT) was the construction of a cofferdam at the tube/ventilation building interface. The ventilation building was to be built as part of another contract. The construction of the cofferdam and the excavation to the building subgrade was the responsibility of J.F. White Contracting Company.

Jan 1, 1994

By J. F. Jackson, R. W. Mau

"The first commercial installation in the mineral industry of the ""Verti-Press"" pressure filter was made by Falconbridge Limited at the Strathcona Concentrator to filter copper concentrate. The filtercake produced contains 6 - 7% H2O, an improvement from the 12 - 13% H2O produced by an internal drum filter, at rates of up to 20 t/hr. A novel slurry feed system incorporates a hose pump and a pressurized slurry accumulator.INTRODUCTIONIncreased copper production from Falconbridge Limited operational mines in the Sudbury Area has exceeded the current refinery capacity. A copper concentrate has been produced to overcome this constraint and has been shipped to custom smelters either as a slurry or as a 12 - 13% moisture filtercake utilizing an internal drum filter.With the treatment of the new Deep Copper Zone from the Strathcona Mine, copper concentrate production was forecast in excess of the installed dewatering capacity. The filtercake was too wet to transport by truck and the custom smelter refused to handle this product at the truck unloading site. The filtercake had to be trucked to a rail spur and transloaded into gondola cars. This system was expensive, incurred unaccountable losses and the concentrate was assessed a moisture penalty.To reduce the concentrate moisture content to permit direct shipment by truck, two basic systems were available; vacuum filter followed by a thermal dryer or a pressure filter. Past experience with the high capital and operating costs of dryers led Falconbridge to closely examine the pressure filter alternative.COPPER CONCENTRATE PRODUCTIONThere are two separate circuits at the Strathcona Mill; one treating nickel ore and the other treating copper ore.The rougher concentrates produced by both circuits are conditioned with lime and cyanide before the copper-nickel separation in a flotation columns. The concentrate consisting of cha lcopyrite with mi nor cubanite is very clean as shown in Table I. Currently 50% of the copper in the plant feed reports as copper concentrate, in the past, this has been as high as 70%."

Jan 1, 1990

To gather additional field data from the western United States, researchers from the National Institute for Occupational Safety and Health (NIOSH) installed an array of field instrumentation at a longwall coal mine in Central Utah. The purpose of this field site was to monitor ground movement and changes in pressure during mining where conditions include massive, stiff overburden and relatively deep cover. To accomplish this, field instrumentation was installed in the two-entry gate road between the fifth and sixth longwall panel in the current mining district.

Jan 7, 2020

By H. P. Greenwald, H. C. Howarth

There was reported in Bureau of Mines Technical Paper 5754/ a series of tests to determine the compressibility and bearing strength of specimens prepared from blocks of potash salt obtained from a mine near Carlsbad , N. Mex . The events leading up to the investigation were sketched in a foreword by George S. Rice , then chief mining engineer of the Bureau ( retired September 30 , 1937 ) ; this foreword also gives a discussion of the possibility of increasing the ultimate total recovery of the potash salt by " second mining" of pillars or by use of a longwall system . In June 1936 , Rice and the senior author visited Carlsbad with H. I. Smith , chief of the mining division of the Geological Survey , to observe mining then in progress and to discuss with the management of one of the mines records of convergence of roof and floor which they were obtaining . It developed that serious thought was being given to the possibility of roof failure resulting from shear at the faces of pillars . There was envisioned the danger of such cracks extending upward to water - bearing strata . Obviously , the simple compression tests of the potash salt then being made would throw no light on this question , and tests of assemblies of potash and roof salts would have to be made . In this connection it is to be remembered that in the mine no sharp division exists between the potash salt being recovered and the nearly pure halite which forms the roof . The interlocked crystalline structure is continuous , and there is merely a very rapid decrease in the proportion of sylvite in a short distance vertically . Figure 2 of Technical Paper 575 shows that two samples near the top of the salt being mined contained , respectively , 51 and 65 percent potassium chloride . Contrasted with this is an analysis of the roof salt given on page 24 of that publication , which showed only 3.6 percent potassium chloride . As the data given in Technical Paper 575 show , the roof salt is much less plastic than the potash salt . The immediate roof may then be thought of as a more rigid stratum of indefinite extent resting on and continuous with yielding supports and loaded uniformly at the rate of 900 to 950 pounds per square inch . Just what thickness of the salt should be considered as immediate roof is uncertain .

Feb 1, 1938

By Alan B. Wagner

The River Tower is a proposed 27-story condominium building in the heart of downtown Milwaukee, Wisconsin (USA). The tower will be over 100 m tall, and will have a ground area measuring 15 m by 40 m. The structure will be constructed of cast-in-place reinforced concrete. Certain transfer girders and stabilizing diagonals will be constructed of post-tensioned concrete. Vertical loads will be transmitted through an arrangement of columns, bearing walls, and elevator and stair cores. A mat foundation will be used to connect and integrate these load-carrying elements. The site's geologic profile includes 8.4 m of compressible estuarine (organic) deposits. To control settlement, the mat will be pile-supported. These deposits are underlain by moderate-strength inorganic deposits that extend to bedrock at 32 m.

Jan 1, 2002

By Takefumi Takuma, Masashi Nagano, Christopher DellAringa

Multiple agencies in Southern California are retrofitting and upgrading their levees to catch up with ever-advancing urbanization affecting the requirements for existing channels and levees in this seismically active zone. Pressed-in sheet piles have been specified on some of these projects to minimize noise and vibration problems associated with sheet pile installation. This paper will study three Southern California levee and sewer pipeline retrofit projects that utilized pressed-in sheet piles in hard soil conditions with N-values higher than 50. BACKGROUND Southern California is home to numerous drainage channels fortified with earthen levees. In spite of the region’s semi-arid climate with varying annual precipitation from year to year, winter storms can bring in heavy and continuous rainfall to the area which overwhelms the levees’ capacities at times. Some levees are running through densely populated areas with homes and other sensitive structures such as underground utilities and bridge piers. Conventional sheet pile driving utilizes either percussive or vibratory pile driving methods, both of which generate high levels of noise and vibration, causing nuisance and potential damage to nearby structures. On the other hand, the press-in piling method utilizes a hydraulic force to push piles into the ground, thus practically eliminating the noise and vibration issue. Although there are types of press-in piling systems mounted on tall leaders on large crawler-base machines, they are less frequently used due to its much larger size and more limited drivability than the type discussed hereunder. The other type of press-in machine sits on top of already installed piles and is anchored with its own weight and additional counter weight when starting off as shown in Figure 1. Once the first few piles are pressed in, the equipment grips on top of the installed piles and moves forward on its own as the pile installation progresses. See Figure 2. This method does not use a vibratory or percussive force to install piles.

Jan 1, 2018

Study on Influence that Styrene-Phosphoric has on the Surface Property of Rutile Minerals

Sep 13, 2010