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(There are 82 Local Sections in the United States, 10 Foreign) ADIRONDACK Established June 18, 1952 Official year begins in January Meets next to last Saturday monthly April through October Local Section Dues AIME Mbrs $2 Affiliate Mbrs $3 Severn P Brown, Chairman George E Erdman, Vice-Chairman Patrick F Farrell, Secretary-Treasurer Republic Steel Corp Mineville, N Y

Jan 1, 1960

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Jan 1, 1960

By Tiebao Yang

In high pressure die casting processes, a die plays a critical role in removing heat from the molten metal during the cavity filling and solidification stages. Proper control of die temperature is essential for producing superior quality components and yielding high production rates. This paper proposes a local temperature control scheme for die thermal management based on a computerized intelligent real-time monitoring and control system (IRMCS). In this scheme, cooling water lines are controlled by a pump and solenoid valves. A controller is designed according to the law of die temperature fluctuations. The results obtained from the experiments carried out on a laboratory die casting process simulator indicate that the controller can limit the local die insert temperatures in a given band. Hence, the desired thermal pattern of the die insert becomes achievable.

Jan 1, 2006

By Yuri Hovanski, Jingyi Zhang, David P. Field, Piyush Upadhyay

Friction stir welding has gained wide interest in industry and drawn large research attention due to its high level of automation and superior joint performance. In this study we further expand the welding parameters to be of magnitudes higher than those previously reported to lower the cost and enable high volume joint production. Sound butt-joints were produced with aluminum alloy 6111-T4 blanks with welding speeds up to 6000 mm/min. Tensile tests of the joint pieces show >97% joint efficiency in terms of ultimate tensile strength. The T4 natural aging and grain refinement is found to contribute to the superior joint properties. Electron backscatter diffraction (EBSD) analysis is used to qualitatively study the local shear texture inside the nugget zones of the welds. The shear texture result is a good indicator of the material flow directions in the nugget zones. The flow directions behind the rotation tool are found to be flattened towards the top surface of the workpiece when the welding speed is increased, suggesting intense material mixing and transportation along the longitudinal welding direction (WD).

Mar 1, 2018

By F. A. Guo

Ultrafine-grained surface layers were obtained by surface mechanical attrition treatment (SMAT) in copper and titanium samples. The thermal properties of the deformed layers were characterized using a scanning thermal microscopy (SThM) that allows thermal conductivity to be mapped down to the submicrometer scale. A theoretical approach, based on this investigation, was used to calculate the heat flow from the probe tip to the sample and then estimate the thermal conductivities at different scanning positions. Experimental results and theoretical calculation demonstrate that SThM can be used as a powerful tool for the thermal property and microstructural analysis of ultrafine-grained microstructures.

Jan 1, 2006

By R Saha, D Barry, C Mawdesley, O Bertoli

Kriged estimates are not typically calculated on blocks substantially smaller than the sample spacing (eg the Standard Mining Unit or SMU). Moreover, the sample spacing for quality variables is often much greater than the SMU size. For short to medium term planning decisions, the shorter term variability in the quality variables is a key economic consideration in defining, setting and meeting coal product specifications.Global uncertainties can be calculated using Drill Hole Spacing Analyses (DHSA). However, knowing the precision of a variable for a one or two year production volume is usually not adequate for variables with low spatial continuity that may fluctuate significantly over daily, weekly, SMU, or shipment volumes.Is there a feasible, reasonable and valid geostatistical method to model the uncertainty of coal quality variables on blocks substantially smaller than the drill spacing (say on the SMU)?The validity of using co-kriging variances, calculated on SMUs to characterise local uncertainty, was tested using a suite of conditional simulations generated for several quality variables for BHP’s Blackwater operation. The conditional simulation results were used as a benchmark against which the results derived from the kriging variances could be compared.The agreement between the kriging and simulation methods for thickness is excellent, with much closer correlations than for the quality variables. Typically, the kriging variances give very reasonable approximations to the simulation-based uncertainties, although there could be some systematic discrepancies which may become much more critical if a classification is to be based on a thresholding of the SMUs relative uncertainties.CITATION:Mawdesley, C, Barry, D, Bertoli, O and Saha, R, 2017. Local uncertainty benchmarking – a coal case study, in Proceedings Tenth International Mining Geology Conference 2017, pp 43–50 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 20, 2017

By Mohammad. M. Khajeh

Rock mechanical properties are important parameters in geomechanical simulation. Considering stochastic heterogeneous models rather than conventional homogeneous layer cake models leads to more realistic simulation results and uncertainty assessment. These heterogeneous models are usually fine scale models generated by geostatistical techniques. Although considering high resolution property models is desirable, geomechanical simulation with a fine scale model is not computationally feasible for full?field, coupled geomechanical-flow simulation. Upscaling of property models is necessary to move from fine scale/high resolution property models to coarser scale/low resolution models appropriate for simulation. Local numerical upscaling was proposed by Khajeh et al. (2012) to describe the macroscopic elastic behavior of complex heterogeneous media and is expanded upon in this work. This numerical technique is not restricted to specific geologies as typical analytical techniques are. Moreover, transversely isotropic deformation is considered rather than the usual assumption of isotropic deformation. To compare the accuracy of the upscaling methodology, in this study shear strain is considered as the geomechanical response of a synthetic facies model and the response of the coarse scale model is compared to other conventional analytical averaging techniques. It is found that the numerical upscaling technique better approximates the geomechanical response of the fine scale model.

Jun 1, 2012

By Geoffrey C. Hebner

Augered, cast-in-place piles (ACIP) have become a very common foundation type in Atlanta and the Southern Piedmont Province as well as much of the United States in the past 20 years. Prior to the introduction of ACIP foundations in Atlanta, the most common deep foundation type was Raymond piles. Raymond piles are basically a driven, thin-walled step-tapered steel pile filled with concrete. Drilled piers were also relatively common and continue to be used, particularly in shallow bedrock or high column load situations. Driven piles, including pipes, H-sections, and timber piles were previously common with working loads typically in the 30 to 50-ton range. Initially, ACIP foundations had similar allowable capacities, however, over time improvements in installation techniques and equipment have resulted in an increase in allowable ACIP capacities. Correspondingly, they have become a more cost-effective and trusted foundation for geotechnical and structural engineers. Over the next several decades many other deep foundation alternatives began to lose popularity. ACIP are one of the predominant deep foundations in Atlanta and the Southern Piedmont today. Although ACIP foundations have widespread popularity in the private sector, they have not been readily accepted currently by government transportation agencies. ACIP may be used by some of the smaller municipalities, but to the author's knowledge, have not been used with regularity by larger, state agencies.

Jan 1, 2003

By M. Ye. Melnikov

The report is about oceanic ferromanganese crusts ? covers of iron and manganese hydroxides developed over an opened rock of seamounts and rises. Ore bed parameters of crusts are understandable as their thickness and content of main economic components ? manganese, cobalt and nickel. All known results of research activity on ferromanganese manganese crusts point to that crust are characterized by notable variability of thicknesses and composition. It is possible to separate few levels of variability. The most evident is the first level of parameters variability, which is manifested in various regions of the Ocean, and connected first of all, with an age of submarine mountains, a host objects for a crusts. It was proved by many authors, that most powerful crusts are connected with submarine mountains of Cretaceous age. [1]. Crust thickness at the Magellan Seamounts reaches, for example 12-15 cm, sometimes exceeds 20-22 cm. Thicknesses of Hawaii Archipelago or Tuamotu crusts in 3-4 times less. Biostratigraphy studies of crustal sections at the Magellan Seamounts already show, that its main part started to form in the Late Paleocene. Four layers with well expressed features in structure and composition of a layer are separated in the section. From foot to top: Late Paleocene ? Early Eocene layer I-1, Middle-Late-Eocene layer I-2, Miocene layer II and Pliocene ? Quaternary layer III. Relics of more ancient Campanian ? Maastrichtian ore layer [2, 4] were discovered. It is evident for example, that Oligocene mountains could not be a host for two lower layers in the crust section.

Jan 1, 2010

By M. Ye. Melnikov

The report is about oceanic ferromanganese crusts ? covers of iron and manganese hydroxides developed over an opened rock of seamounts and rises. Ore bed parameters of crusts are understandable as their thickness and content of main economic components ? manganese, cobalt and nickel. All known results of research activity on ferromanganese manganese crusts point to that crust are characterized by notable variability of thicknesses and composition. It is possible to separate few levels of variability. The most evident is the first level of parameters variability, which is manifested in various regions of the Ocean, and connected first of all, with an age of submarine mountains, a host objects for a crusts. It was proved by many authors, that most powerful crusts are connected with submarine mountains of Cretaceous age. [1]. Crust thickness at the Magellan Seamounts reaches, for example 12-15 cm, sometimes exceeds 20-22 cm. Thicknesses of Hawaii Archipelago or Tuamotu crusts in 3-4 times less. Biostratigraphy studies of crustal sections at the Magellan Seamounts already show, that its main part started to form in the Late Paleocene. Four layers with well expressed features in structure and composition of a layer are separated in the section. From foot to top: Late Paleocene ? Early Eocene layer I-1, Middle-Late-Eocene layer I-2, Miocene layer II and Pliocene ? Quaternary layer III. Relics of more ancient Campanian ? Maastrichtian ore layer [2, 4] were discovered. It is evident for example, that Oligocene mountains could not be a host for two lower layers in the crust section.

Jan 1, 2010

By Stephen D. Schwochow

Aggregate producers nationwide well recognize the numerous problems often faced in securing local approval to open and operate new gravel pits and rock quarries. Similar problems are faced in Colorado, but this region also presents certain political, social, and geological complexities that have become particularly troublesome in the last 10 years. The gravity of the local permitting dilemma can be related directly to the worsening supply-demand imbalance for aggregates in the state's most populated area, the Front Range urban corridor, particularly the Denver metropolitan area. The drive to develop crushed-rock reserves to supplement dwindling alluvial supplies and to meet increasing regional growth demands was somewhat predictable but perhaps more a "last resort" alternative forced onto producers by a hesitant and often apathetic government.

Jan 1, 1982

By I Douglas, L Allen

Localised indicator kriging was developed following a similar approach used by Marat Abzalov (2006) in his paper titled æLocalised uniform conditioning (LUC): A new approach for direct modelling of small blocksÆ. Abzalov introduced the idea of mapping panel distributions from uniform conditioning onto selective mining unit-sized blocks that were created using ordinary kriging. This concept of remapping panel distributions was applied to multiple indicator kriging histograms.At Newmont a program was developed that made the remapping of MIK histograms to SMU sized blocks extremely efficient and was subsequently tested on several gold deposits. The results have been encouraging as the localised indicator kriging (LIK) method has eliminated many issues that have plagued both ordinary kriging and multiple indicator kriging. Use of localised indicator kriging methodology limits the smearing of high-grade and the over-smoothing of grade that is common and difficult to control in OK but retains the ability for localising grades. LIK also simplifies change-of-support corrections, eliminates un-mineable slivers of low or high-grade when dealing with small tonnages, and allows for the mapping of linear and non-linear estimates into the same block.

Sep 26, 2011

By W Assibey-Bonsu

The paper provides a brief review of the multivariate uniform conditioning and the localised multivariate uniform conditioning techniques and presents a case study based on a porphyry copper gold deposit in Peru. Two other important scenarios have been investigated and will be particularly emphasised: The recovered selective mining unit (SMU)s depend on a combination of copper and gold content, which can be expressed by means of ænet smelter returnsÆ (NSR). Two approaches are compared. Firstly, the application of a composite cut-off on NSR on the joint distribution of each grade and the application of uniform conditioning to three variables is investigated, ie for the first approach NSR is used as the main variable. The second approach considers copper as the main variable. In the case of multiple domains the procedure used to apply the technique to process mixed panels is clarified and recommendations are made.

Sep 26, 2011

By John S. Stevenson

Zeballos mining camp is on the west coast of Vancouver island; 195 nautical miles northwest from Victoria.; The spectacularly rich gold-bearing veins that made Zeballos an important; gold camp were found early in 1934. Small pockets of very coarse; gold had been found earlier under large boulders at the mouth of Spud; creek; and in the autumn of 1933 rich gold-quartz float was found near the; mouth of the creek. The rocky beds of the steep creeks entering Spud creek; were searched for its source and as a result the veins on the White Star property; were found. The Goldfield vein on the Spud Valley property was discovered; in 1935; and the No. 1 vein on the Privateer in 1936. In the general; prospecting activity that quickly followed; other veins were found; not; only in Spud creek but in other creeks draining into Zeballos river.

Jan 1, 1954

By Arthur Baker

The orebodies are long bedding-plane lenses of chalcopyrite and sphalerite, associated with garnetite masses. Most of the orebodies are within a 50-ft thickness of Cambrian limestone; other Paleozoic limestones and dolomites are locally metamorphosed but only slightly mineralized. Pre-mineral faults are numerous, but shallow folds were the main ore-localizing structures.

Jan 12, 1953

By Matheus Jacon Pereira

Existe uma tendência de aumento na utilização da tecnologia de RFID na automação industrial, bem como em outros setores: varejo, aviação e transportes. Com o RFID, um objeto pode ser identificado por uma etiqueta eletrônica e sua existência constatada automaticamente. No entanto, sua localização exata permanece desconhecida para os usuários. Para a localização, os estudos realizados são satisfatórios quanto as técnicas de rastreamento de etiquetas RFID, porém, não consideram as possíveis interferências na comunicação provocadas pelos objetos presentes em locais reais. Este trabalho propõe um ambiente de laboratório que simula as interferências do Ambiente Industrial nas técnicas de localização indoor de etiquetas RFID, como obstáculos na comunicação entre etiquetas e antenas RFID; e materiais usados na fabricação das superfícies dos objetos, sobre as quais a etiqueta RFID é aplicada. Os resultados mostram que as técnicas RSSI e AoA são adequadas para localização indoor de etiquetas RFID, sendo que a segunda técnica permite maior exatidão na localização.

Oct 30, 2017

A new method, localized uniform conditioning (LUC), was proposed in 2006 for modelling grades of small blocks of ore when data spacing is too broad for their accurate modelling by the linear regression based techniques, such as kriging (Abzalov, 2006). It represents a modified uniform conditioning (UC) technique that calculates the grade distribution functions for the large panels. LUC uses partitioning of the panels onto the small blocks and then ranks them in increasing order of grade. Based on the block ranks, a single grade value can be deduced for each block from the UC model of the gradetonnage relationships of the corresponding panel. After being first presented in 2006, the LUC method has been implemented in ISATIS© (commercial software) and became one of the common approaches for grade estimation when data spacing is broad in comparison with the estimated block size. Several years of study on the LUC method and its application to different geological environments, have allowed identification of the strengths and weaknesses of the method, which are as follows: ? The method produces accurate grade-tonnage functions, which are in a good accordance with a volume-variance relationship principles ? An initial ranking of the selective mining unit (SMU) blocks can be made by direct kriging from the sparse data grid. Therefore, the LUC method can be particularly useful at the early stages of exploration and mining project evaluations when sparsely distributed data is often the only available information ? Accuracy of the local estimation depends on the SMU ranking techniques. When ranking performed by direct kriging of the SMU blocks their spatial distribution is approximate. When the variogram of the studied variable is characterized by a large nugget effect, the block ranks produced by kriging can significantly differ from their ?true? distribution ? Block ranking can be improved using auxiliary data, either geophysical or geochemical. This allows use of the LUC method for integrating different data sets. In particular, LUC can be used for grade control in open pits by integrating resource definition data (e.g. drill-hole assays) and blast-hole assays. The latter are used for the block ranking.

Jan 1, 2014

By Yi Luo, Jianwei Cheng, Mingming Li, Lei Xiao

Concealed thermal events in longwall gobs present safety hazards for underground coal miners and can significantly interrupt mining production. The probable causes for such thermal events range from coal oxidation at slightly above ambient temperature to smoldering fires due to spontaneous combustion of the broken coal left in the gobs. Locating such “hot spots” is the key step for planning and implementing mitigation measures to bring such thermal events under control. If a mine section, or even an entire mine, has to be sealed, understanding the status of the sealed mine atmosphere is important for the decisions guiding subsequent actions. The gas composition data obtained through the tube bundle mine atmospheric monitoring system is firsthand information of great value. Fire ratios proposed by various researchers and derived from gas composition data are useful in determining the fire status and even approximating the source locations (Timko and Derick, 2006). However, the applicability of each of these ratios under particular conditions should be carefully evaluated. The use of properly combined fire ratios can enhance the certainty of analysis. The explosibility of a sealed mine atmosphere deserves primary concern for safety reasons during seal construction, idle time and reopening of the sealed area.Mine atmospheric monitoring data from a longwall mine with flame fire have been analyzed. Efforts have been made to identify the possible causes, locations and statuses of these events using the obtained gas data, as well as other ventilation, geological and mining parameters. The effect of injected inert gas to control the events has also been quantified. The explosibility of the sealed atmosphere has been determined using two methods.

Jan 1, 2012

By V. Maazallahi, A. Rouleau, A. Saeidi

"The geometry of the terrain topography before and after the failure are the essential factors for analyzing a landslide and for the design of remedial works. This paper presents a method to determine these factors, considering that the determination of the slide surface profile is difficult and costly using traditional methods and the pre-slide topography data is often not available. The presented method to locate the 3-dimensional geometry of the slide surface is based upon determining the slide surface in 2- dimensional vertical sections. This method utilizes post-slide topography of the area to determine the pre-slide topography and uses equations to estimate the pre-slide situation using a statistical process applied to points located on the sliding mass. This method is tested on the Maskun landslide in Iran. The results indicate the applicability of the proposed method to obtain the key factors for the back analysis of a landslide in a cost effective manner.INTRODUCTIONProbably the most reliable method of determining the strength of soil and rock mass is to back analyze a failed or failing slope (Caia et al. 2007; Wyllie & Mah, 2004). This method is used in geotechnics for estimating geotechnical parameters of the rock and soil mass (Sakurai et al., 2003; Frayssines and Hantz, 2009; Cepuritis et al. 2010), but it requires that the failure mode is well established and that there is complete and precise information available on the slide surface and the sliding mass (Sjöberg, 1996). Measurement of the slope profile before failure provides the basic information required for a back analysis (Hock & Bray, 1981). The post-slide topography is another key factor. The back analysis process for determining the actual strength parameters of soil or a decomposed rock mass after a landslide requires knowledge of the sliding mass geometry, both before and after the sliding event. Many studies are reported in the literature about the application of back analysis for determining geotechnical and geomechanical parameters of rock and soil mass (Sakurai et al., 2003; Cepuritis et al. 2010; Frayssines and Hantz, 2009, Hussain and Stark, 2011), but they generally present little information about the geometry of the slide surface, and the weight of rock and soil mass that slid, although these factors are the most important parameters for back analysis process. Liang and Xue-song (2012) determined the slip surface having the minimum factor of safety (called critical slip surface in deterministic analysis of slopes) and the slip surface with the minimum reliability index (called critical reliability slip surface), but they have not considered the actual profile and geometry of the slide surface. Rocscience (2013) proposes the back analysis option in the Slide software for slope stability study, but it requires an imposed slide surface as input; alternatively, one can estimate by a finite element analysis the surface with the minimum factor of safety. However, this estimated surface is very likely different from the actual sliding surface, considering the uncertainties in input data of the finite element method."

Jan 1, 2015

By F. E. Armstrong

The Bureau of Mines has conducted a research program to systematize the art of locating uncharted and lost oil and gas wells that penetrate coal seams; this publication presents a preliminary summary of its findings. Although no method or combination of methods will guarantee finding all uncharted and abandoned wells in a particular area, at least 75 percent of such wells can be located by compiling and applying all available information and using modern metal detectors.

Jan 1, 1973