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By D M. Frantois-Bongarton

Variograms can be powerful tools for the analysis and control of process streams and their sampling. Their uses and proper utilisation have been described somewhat unclearly to date, and their limitations and precautions of use are too rarely mentioned. The general meaning and properties of the variogram tool and its use in geostatistics are therefore reviewed in details to derive a critical view of its proper use for process control: what to expect from it and what it cannot deliver and which uses are illusory or potentially misleading. A summary of GyÆs seminal work accompanies this essay to put the concepts into historical perspective.CITATION:Frantois-Bongarton, D M, 2012. Review of variogram properties and remarks on its use in process control, in Proceedings Sampling 2012 , pp 175-180 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 21, 2012

By P. B. Leavenworth

Development in the Upper Texas Gulf Coast during 1945 resulted in the discovery of 23 new fields; one Miocene, eight Frio, three Cockfield-Yegua and eleven along the Wilcox trend. The Wilcox trend appears to he the most active at this time. Producing depths of the new Wilcox discoveries range from 2050 to 10,050 ft. Drilling along the Frio trend has been, for the greater part, projected to the deeper downdip sands. Eighteen of the new discoveries are classified as oil or condensate and five are gas discoveries.

Jan 1, 1946

The principal source of funding the working capital requirements of gold miners has traditionally been equity. However in the 1980s, with a substantial increase in activity in the exploration for, and the production of, gold the traditional sources of equity finance became no longer sufficient to meet demand. With the often high cost of raising equity, the need for developing alternative financing structures became critical, especially since the stockmarket crash of 1987 which at least until recently, adversely affected the amount of equity capital available for investment in mining.

Jan 1, 1994

By I M. Turnbull

QMAP (the Quarter Million Mapping Programme, 1:250 000 scale) is a geological mapping programme which will build a digital geological database of the whole country and publish maps and books to document it. The programme was established in 1993, following a recommendation by a review panel appointed by the Ministry of Research, Science & Technology, and is funded by the government, from the Public Good Science Fund. The relevance and fundamental value of QMAP lies in the greatly improved geological knowledge it will provide for researchers and other end-users of geological information.   QMAP research involves assessment of previous work, field and laboratory investigations in key areas, and data storage, manipulation and publication using Geographic Information Systems (GIS) computer technology. The QMAP digital database of New Zealand geology will be completed by 2006, as will the series of 21 full colour printed geological maps and accompanying explanatory texts. Two are already completed and published (Kaitaia and Dunedin), and six other projects are well advanced.   QMAP information will also be available in digital form. Next year we hope to expand the scope of the programme to cover the reconciling and linking of many other earth science databases to QMAP, because we believe this will create a powerful research tool. The intention is to develop internet access to the databases, to make the information publicly available.

Jan 1, 1997

By Harold M. Smith

Among the more important raw materials now utilized for the commercial production of synthetic organic chemicals is natural 'gas. Natural gas has been used as a fuel and source of energy almost from its discovery, but its potentialities as a chemical raw material were not realized until recently. Research in the use of natural gas for Chemical synthesis received great impetus from the discovery by Brooks and Humphrey4/ in 1918 of alcohols in the diluted ?acid oil? obtained by sulfuric acid treatment of cracked petroleum distillates. Experimental data soon showed that hydrocarbons from natural gas could be converted to these same products. Laboratory methods for chlorination of natural-gas hydrocarbons, particularly of methane for the production of methyl chloride, methylene chloride, carbon tetrachloride, and chleroform were known before that time but were not developed commercially. Methods for obtaining alcohol by oxidation of hydrocarbons derived from natural gas also were known before 1918 but had not received commercial consideration. Since 1918, and particularly during the past 15 years, the work of chemists and chemical manufacturers throughout the world has resulted in an accumulation of data regarding the reactivity of natural-gas hydrocarbons, and related hydrocarbons found in refinery gases or made synthetically. These data have been used to develop methods for converting hydrocarbons into chemical products and thus form the basis for a large and growing industry.

Jan 1, 1947

By Roger C. Malan

The Monument Valley and White Canyon districts are in northeastern Arizona and southeastern Utah. Exploration and mining for uranium has been conducted in these districts since the late 1940's. In July 1965, ore reserves plus ore production at 174 properties were approximately 3.3 million tons of ore containing about 19 million pounds U3O8, of which about 10 per cent remained in reserves. The two largest mines, Monument No. 2 and Happy Jack, together account for about 45 per cent of the sum of production and reserves. Approximately half the deposits in these districts contain less than 1000 tons of ore. Nearly 5000 feet of Permian, Triassic, and Jurassic sedimentary rocks, mainly continental in origin, are exposed in these districts. All the important uranium deposits are in the Shinarump, the basal member of the Chinle Formation of Triassic age. The Shinarump lies on a widespread unconformity. It is composed of fluvial sediments, generally less than 100 feet thick, that were deposited by streams flowing from a source to the south. Most of the deposits are in an arcuate belt, convex to the west. This belt, 3 to 12 miles wide, extends from Monument Valley northward nearly 130 miles. It is along the western flank of the ancient Monument Valley-Monticello upland, an area that was slightly uplifted at the beginning and again at the end of deposition of the Shinarump. Erosion and subsequent reworking of the Shinarump sediments in the vicinity of this upland are postulated to have made possible the transportation, in solution, of the uranium contained in these sediments. The soluble uranium probably was carried by migrating ground water into sites favorable for precipitation in Shinarump beds bordering the upland. Thus, the original very small amounts of dispersed uranium in the early Shinarump sediments were accreted in the favorable belt where the accumulations of carbonaceous plant remains and their decay products provided a persistent reducing environment.

Jan 1, 1968

By G. van Aswegen

Seismic monitoring became commonplace in the deep South African gold mines in the early 1990’s. The discipline has, to a large extent, developed beyond the ‘research’ stage, and a ‘Guide to Seismic Monitoring in Mines’ has been accepted by the Department of Minerals and Energy1. Although ongoing research is a requirement for the achievement of all the objectives of seismic monitoring in mines, sufficient knowledge exists to apply seismic monitoring for routine seismic hazard assessment as an aid to risk management. The design and management of seismic monitoring systems can be tested against requirements spelled out in the ‘Guide’. Assuming the seismic monitoring system performs as per requirement, the best practice for routine seismic hazard assessment in mines includes • Long term seismic hazard assessment: through back analysis of seismic data and correlation with numerical modelling output, reasonable tests for planned mine designs are possible. • Medium term seismic hazard assessment: o Spatial analysis through contouring of seismic strain related parameters, with superimposed contours or event plots of stress related parameters allow the delineation of potential instabilities in space. o Quantitative and statistical analyses of seismicity in smaller spatial units (usually encompassing production sites) allow the comparative seismic hazard rating of different areas/sites so that rock engineering input and risk management can be optimised • Short term seismic hazard assessment relies mainly on time history analyses of particular seismicity parameters. The temporal patterns are controlled by a combination of temporal and parameter filters, the optimisation of which determines the success rate.

Jan 1, 2003

By K. E. Barnes

"The “Jameson Cell” flotation cell was developed at Mount Isa Mines in the late 1980’s to address deficiencies in our flotation column installations. Early base metal installations had a variable record. The test work and trials showed they made an improvement metallurgically when operated correctly, but performance of the early installations was hindered by a range of operational and maintenance issues. The installations needed to be more robust, and we needed a better understanding of how to successfully integrate the cells into the plant flow sheet.During the 1990’s, Jameson Cells had great success in coal fines flotation and organic removal in SXEW applications, and became the standard in these applications in Australia. These installations improved the cell design and materials of construction and the cell flow sheet design, to make it low wear with self-regulating control, producing good performance with little operator input.These improvements have enabled a fresh look at the use of Jameson Cells in base metals. Recent new installations have shown significant benefits in “hybrid” circuits, that combine the best features of both Jameson Cells and conventional flotation cells, achieving better overall circuit performance in a smaller footprint than either technology could do by itself.Case studies of successful base metal applications are discussed, using size-by-size mineralogical performance to explain the improved circuit performance. The new methods of flow sheet test work design are also described."

Jan 1, 2006

By A D. Campbell

Conversion of Mineral Resources to Ore Reserves requires a multidisciplinary approach and application of a number of Modifying Factors. The Modifying Factors for mining, particularly dilution and recovery in a caving mine are complex and can be difficult to determine. Cave flow modelling software is widely used for mine planning, scheduling and forecasting metal production. However, the conversion of Mineral Resources to Ore Reserves remains a difficult and subjective process and a consistent approach to convert Mineral Resources to Ore Reserves as part of the cave flow modelling process is not published in the literature. This is due to the difficulty in estimating the Ore Reserve that remains as cave stocks at a particular point in the mine schedule, the recovered tonnage and grade of the diluting material at various stages in the mine life, as well as the Mineral Resource classification of both the recovered and diluting material that forms the Ore Reserve. The key principle of this paper is the tracking of the Mineral Resource classification in the flow model used to estimate the Ore Reserves. This is critical to defining the Ore Reserve as Proved or Probable and enabling transparency in the reporting process. An approach for dealing with mineralised external dilution in the Ore Reserve estimation process is also provided.This paper outlines the approach to convert Mineral Resources into Ore Reserves developed at the Ernest Henry mine sublevel cave (EHM SLC). The same method could be used in any cave mine and applied at any stage of the mine life. The process replaces broad-brush assumptions for the mining Modifying Factors, such as dilution and recovery, as these are determined numerically as part of the model computation. This paper explains the Ore Reserve estimation method with a worked example to enable the reader to adopt the process at any caving mine. Mineral Resource classification within the block model is embedded in the cave flow model and the flow model results used to attribute tonnes, grade and the mixed proportions of the Mineral Resource classification for material extracted from each drawpoint. This information is then used to convert planned mine production into the appropriate Ore Reserve classification. Since the flow model simulation follows the mine schedule, it can be used to predict depletion and cave stocks at any stage of the mine life, and can calculate a residual block model at the end of the mine life. The accuracy of the flow model is checked by validating the forecast ore grade and metal tonne with reconciliation data from the concentrator which is also used to calibrate the flow model.CITATION:Campbell, A D, 2017. A simple and accurate method for Ore Reserve estimation and Mineral Resource depletion in caving mines, in Proceedings 13th AusIMM Underground Operators’ Conference 2017, pp 253–260 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Oct 16, 2017

By Hamid Maleki

A comprehensive study consisting of stress determinations, core logging, laboratory testing, and numerical analyses was conducted to investigate the cause and potential alternatives to the coal bump conditions that developed in the Second North Panel of the Little Dove mine near Buntington, Utah. Roof rock characteristics were such that a cave did not develop above this 420 ft wide panel. After 700 ft of pillar retreat, severe coal bump conditions developed during pillar mining. The coal bump conditions resulted from excessive pillar stress which was caused by load transfer from the extracted, noncaving, portion of the panel. Site specific data and numerical modeling techniques were used to back-analyze the bump prone condition. This back- analysis lead to the identification of critical stress, closure, and energy release levels. These critical levels were then used to evaluate alternative pillar mining sequences in the hope that the potential for coal bumps could be reduced. It was found that while alternative sequences offered some potential improvement over the pillar mining sequence used in the mine, alternative pillar mining sequences would not significantly reduce the potential for bumps. For the roof characteristics at this mine, coal bumps are best avoided by developing narrow panels or significantly wider panels, which incorporate properly sized barrier pillars. Narrow panels, on the order of 300 ft, would not cave, but panel pillar stresses and the potential for umps would be moderated by the reduced r' panel width. Wider panels, of approximately 650 ft, would allow a cave to develop, also reducing panel pillar stresses and coal bump potential.

Jan 1, 1987

By George Chung

"The Iron Ore Company of Canada's Carol Lake Project is Located near the western boundary of Labrador, 960 air kilometers northeast of Montreal (Figure 1).The Concentrator operation was started in 1962 with a capacity to produce 7 million tonnes of concentrate per year. The bulk of the concentrate was pelletized at a 6 million tonnes per year pelletizing plant completed in 1963. The remaining concentrate was sold in the international market. The concentrator was first expanded in 1966 to 10 million tonnes per year capacity with the pellet plant also expanded in 1967 to match the increase in concentrate production. In 1973, the concentrator was further expanded to gear with the increase in concentrate sales. In 1977, more than 40 million tonnes of crude ore was processed to produce in excess of 17.4 million tonnes of concentrate and 10.4 million tonnes of pellets."

Jan 1, 1980

By William H. Snyer

A relatively inexpensive, very fast response photo-optic/fiberoptic system has been conceived, constructed and employed by Denver Research Institute (DRI) to measure charge breakout uniformity on the surface of a very large ANFO detonation. The new equipment and technique was coined OWL (observation without leads). Its unique design provides the ability to monitor or measure detonation velocities and/or detonation breakout characteristics without fiberoptic or any other direct contact with the explosive. This system has proven to be versatile and has been used to measure surface breakout simultaneity on large ANFO detonations, munition case breakout times and velocity of detonation (VOD).

Jan 1, 1990

By H. Z. Kuyumcu

Associated with the development of a novel microbiological oxidation process for the conditioning of iron hydroxide slurries from ferrous mine waters, there is a realistic chance to make the contained iron available for a material utilization. The transformation of ferrous into ferric compounds is coupled with the precipitation of iron hydroxisulphate mostly in terms of the mineral Schwert-mannite. The further treatment of the iron hydroxisulphate has to be aimed on the processing for product recovery and product refinement. For many potential applications, e.g. in the ceramic industry, the pigment industry or for metallurgical applications, the removal of sulphate is essential. For the dehydration of the iron hydroxisulphate and the sulphate removal, microwave heating technology is a beneficial method. In contrast to conventional thermal heating processes the supply of energy in microwave application takes place directly within the material through the dissipation of electromagnetic energy, i.e. no heating medium is needed. It is a volumetric heating process regardless of the surface of the material. The rapid and targeted energy supply and the good controllability of microwave heating systems are advantages which have led to a wide variety of applications in industrial processes. Among the diverse use for heating of temperature-sensitive, chemical and pharmaceutical products as well as foodstuffs the number of applications also in mineral and solid processing increases. At the Department for Mechanical Process Engineering and Solids Processing of the Technical University Berlin the use of microwave technology for the treatment of iron hydroxisulphates has been investigated systematically within the framework of a cooperative research project. The paper at hand shows results from material conversion tests subject to a variation of the relevant process parameters. The reaction products are characterized and the process is compared with the conventional heating in a rotary kiln.

Jan 1, 2014

By Jack E. Brockway

As tunnel boring machine technology has expanded, so has its range of application. Tunneling machines (TBM's) are tackling tasks today that fifteen years ago were considered "inappropriate". A case in point is incline/decline TBM boring. An incline or decline bore presents peculiar design considerations that differentiate it from a horizontal bore. This paper reviews those design considerations as they apply to TBM's, backup, muck handling and other tunneling subsystems. In addition, several abbreviated case studies are presented. By the review of real life tunneling techniques as well as design considerations, the "appropriateness" of TBM incline/ decline boring today becomes apparent. INCLINE Introduction In contemplating the impact of incline versus horizontal tunnel boring system design, the obvious consideration is gravity. Up-hill boring can be quite different than horizontal boring. Muck, water and machine weight all tend to slide down the incline. In addition, hydraulic and lubrication systems if unaltered, will find their fluids pooled in the lower corners contentedly ignoring such higher elevation items as gears and bearings. In order to address this inherent gravity problem, a review of

Jan 1, 1983

By R. Unger, L. Mallett

The use of virtual reality (VR) technologies to train miners is an evolving area in research and development. In July 2006, representatives of 14 international organizations met to discuss current VR-related efforts and explore ways to employ VR in the future. This paper gives an overview of the various approaches presented at the meeting and discusses directions for future implementation. An example of a training package that teaches mine map-reading skills is presented. The meeting was the first step to building collaborations for furthering VR applications for mining. Planning has begun for a 2008 meeting open to broader participation.

Jan 1, 2007

By J. Riss, S. Gentier, A. Marache

The study of the hydromechanical behaviour of fractured rock masses requires a detailed knowledge of the isolated fractures. The aim of the paper is the simulation of the evolution of the void space, located between both walls of a fracture, during a shear test under constant normal stress. Results of the mechanical simulation model are first validated then analyzed in detail. We observe that, during the shear process, there is an opening of the fracture with the creation of preferential channels. These channels are determined at the early phase of the shear process (pre-peak phase), and we observe during the post-peak phase that void areas increase in size rather than the creation of new apertures. Die Untersuchung des hydromechanischen Verhaltens eines zerlegten Felsmassivs erfordert genaue Kenntnisse der einzelnen Spalten. Ziel dieses Artikels ist die Simulation der Evolution des Hohlraumes zwischen den beiden Wänden eines Spaltes während eines Abscherungsexperimentes unter konstantem senkrechtem Druck. Die Ergebnisse der Modellierung werden zunächst mit dem Abscherungsexperiment verglichen und dann im Einzelnen ausführlich analysiert. Während des Abscherungsprozesses tritt eine Öffnung des Spaltes auf, die die Bildung von bevorzugten Fliesswegen fördert. Diese Kanäle werden bereits in einer frühen Phase des Abscherungsprozesses (pre-peak Phase) festgelegt. In der post-peak Phase tritt dann eher eine Vergrößerung dieser Kanäle, als die Bildung neuer Hohlräume auf. L’étude du comportement hydromécanique d’un massif rocheux fracturé ne peut se faire sans une connaissance approfondie des fractures le constituant. L’étude présentée dans cet article concerne la simulation de l’évolution de l’espace des vides présent entre les deux épontes d’une fracture au cours d’un essai de cisaillement à contrainte normale constante. Les résultats du modèle sont tout d’abord validés puis analysés en détail. On constate que, au cours du cisaillement, il apparaît une ouverture de la fracture permettant la création de chenaux préférentiels. Ces derniers sont déterminés très tôt dans le cisaillement (phase pré-pic), et on observe dans la phase post-pic davantage un accroissement de la taille des chenaux plutôt que la formation de nouvelles zones de vides.

Jan 1, 2003

By J. Trow

Dowsing is really IESG which inductively locates electric gradients (dv/dx) on the flanks of SP anomalies. "Sensors" are in one?s head. The "meter" consists of one?s body, limbs, and two $.69 welding rods. The method was calibrated near Mamainse Point, Ontario, where IESG-negative chalcopyrite-bornite-chalcocite-native copper ores reveal mineral zoning related to the IESG-positive Keweenaw fault, down which oxidizing solutions moved. In Michigan, the IESG-positive Keweenaw fault suggests that oxygen-bearing solutions from the Jacobsville Sandstone moved downward to oxidize hydrothermal sulfur to produce native copper, and to supply sufficient water to satisfy Walter White.

Jan 1, 1992

Using Positron Emission Particle Tracking (PEPT) to Investigate Industrial Systems

Sep 13, 2010

By R. L. Bruening, N. E. Izatt, S. R. Izatt

"Rare earth elements (REE) are essential and unique components of many high-technology products without which functioning of modern society would be greatly impaired. Commercial deposits of REE are limited to a few geographical locations. Largely untapped sources of REE are available in endof- life (EOL) magnets, rechargeable batteries, and electronics. Presently, < 1% of REE in EOL wastes is recycled. Conversion of EOL wastes to liquid streams allows use of IBC’s Molecular Recognition Technology (MRT) process to selectively recover, separate, and purify target REE and associated metals at g/L to mg/L or lower concentration levels. The MRT process together with its applications to separations of REE and associated metals in recycling as well as in mining are described. Economic and environmental advantages of MRT are presented. INTRODUCTIONRare earth elements (REE) include the lanthanide series (La-Lu), Y, and Sc. These elements are not rare, but concentrated minable deposits are scarce (Cordier 2012; Haxel, Hedrick, & Orris, 2002). Over 95 % of the world’s supply of REE is controlled by China (Hanson, 2011a) where they are mined, processed, and the pure elements incorporated into a growing number of consumer and military products. The consumer products are marketed worldwide. Since REE are vitally important in consumer and military products, this situation has caused other nations to scramble to develop the capability to produce their own supply (Cordier, 2012).In the U. S., Molycorp has reopened the Mountain Pass REE mine in California and production has begun (Goldenberg, 2010). Development of a reliable internal source of REE is of high national priority in the U.S. (Hanson, 2011b; Hess, 2012: “Obama Announces”, 2012). These elements have in recent decades been incorporated into new consumer and military products that are essential to our economy and defense. These products range from wind turbines, high performance magnets, hybrid car rechargeable batteries, energy efficient lighting electronics, flat screen televisions, and smart phones to advanced weapons systems (Haxel et al., 2002; Levkowitz & Beauchamp-Mustafaga, 2010)."

Jan 1, 2012

By Robert Hopler

A blast caused the destruction of a bridge and loaded freight train and the death of three men, near Chattanooga, Tenn., on May 16, 1907. The blast and its disastrous effect has been described by Mr. Hunter McDonald, M. Am. Soc. C. E., in a paper read before the Engineering Association of the South and reprinted in the Proceedings of the Association for April-June, 1907. The excessive damage was so largely due to coincidence and wreckage of the bridge and train so complete that the incident is worthy of notice.

Jan 1, 2008