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By Jonathan Baggett, Nino Ripepi, Amin Abbasi, Richard Bishop, Juan Monsalve, John Hole

This work focuses on the operational and safety issues associated with karst voids in large opening underground mines. Issues include water inrush, structural instability, and engineering uncertainty in these environments. Coupled with the fracturing prevalent in folded sedimentary rocks, karst voids are complex and challenging ground-control risks. Traditional methods of predicting karst void locations, such as probe drilling, are impeded by the inconsistent spatial distribution and variable sizes of the features as reported by Li et al. (J Rock Mechan Geotech Eng:232–242, 2010) and Hassan et al. (Procedia Chem 19:737–742, 2016). Ground-penetrating radar (GPR) is a geophysical technique that transmits radio waves into a medium and subsequently detects reflected waves via a receiver. The travel time and energy of received signals are then processed and interpreted. The difference in conductivity and dielectric permittivity between limestone and open karst cavities causes strong reflections. GPR is frequently used as a geophysical surveying technique in several industries; however, there is a lack of published research on underground mining GPR applications as reported by Zhao et al. (2015a; Geophys J Int:62–71, 2015b) and Eskelinen and Pellinen (Constr Build Mater:888–898, 2018). The purpose of this work is to demonstrate the use of GPR in an underground stone mine and to discuss the importance of karst void detection ahead of mining.

By Shimi Tzobery, Jay Davenport, Raymond Henn, Sam Bandimere

Over the past several decades, the use of cement-based grouts using ultra fine cement as a replacement for portland cement has begun to gain acceptance as an alternative to chemical solution grouts used in permeation grouting. The amount of information currently available on grouts made with ultrafine cement is limited. The authors used a previously developed field testing program to perform additional tests to evaluate the permeation performance of portland and ultrafine cement-based grouts. For the first time, the 2003 testing program included an attempt to determine the 28 day compressive strength of the sand permeated by the grout.

Jan 1, 2005

By O&apos, M. W. Neill

Mini-piles have been found to be a practical, technically correct remedial underpinning method. They can be constructed in limited access areas with very little disruption. Experience indicated that mini-piles installed using a down-the-hole soil displacement hammer would be particularly effective in the "bottomless" Beaumont Clay formations in the Houston, Texas, U.S.A. area. The University of Houston Foundation Testing Facility was ideally suited to perform tests on mini-piles. The availability of extensive geotechnical data and previous pile test results was invaluable in evaluating the mini-pile test data. As expected, the mini-pile test results were consistant with test results from large sized driven piles in the same soil formation.

Jan 1, 1989

From time to time lead, which is normally considered to be a soft ductile metal, fails by cracking. The cracks which form appear to be of two distinct types-(a) those which follow a zig-zag course around the boundaries of crystals and (b) those which follow a more direct path, frequently two systems of cracks appearing at right angles.The former appear definitely to be associated primarily with the properties of the crystal boundaries, whilst the latter appear rather to be determined by the system of stresses applied. In both cases the lead appears to be a brittle rather than a ductile metal, for the failure occurs without the large amount of deformation usually associated with the tensile breaking of lead. The latter is, however, a function of time and when lead is deformed by long applications of stress, the metal appears to- be less ductile than when the stress is applied suddenly. Thus, if a given test piece of commercial lead is broken by a stress of 1100 lb. per sq. in. in several hours, it may extend 40 to 50%before failing, whereas when broken by a stress of 500 lb. per sq. in. acting for 12 months or more it willshow an extension of only 15 to 25 %. With lower stresses still, failure would take much longer and undoubtedly lower extensions would be obtained.As the stress is lowered it is found that the marked local contraction characteristic of ductile metals becomes less noticeable, and failure, instead of being by extension of *Lecture delivered to the First 'Ordinary Meeting of the Australasian Institute of Mining and Metallurgy, 21st August, 1935.

Jan 1, 1935

By P. J. Closmann

Steam zone growth as a function of time has been calculated for the case of constant rate steam injection into a preheated reservoir. To simplify the calculation a linear temperature profile has been assumed in the cap and base rock at the start of steam injection. The results indicate that at early times augmentation of steam zone growth due to preheating should be greatest. At longer times the steam zone development becomes close to that calculated with no preheating. INTRODUCTION With the increasing application of thermal recovery processes to recover viscous oil, cyclic steam injection has become important in many large-scale projects. In this process, the cycle of steam injection followed by oil production is repeated a number of times. At the beginning of the second and later cycles, steam is injected into a reservoir that has already been heated but that has lost part of its heat both in produced fluids and by conductive heat loss away from the injection zone. In such a case, the temperature level of the injection zone and the temperature distribution of the surrounding rock will affect the growth of the steam zone developed during the subsequent steam injection. Knowledge of the size of steam zone developed is important in determining the amount of oil displaced and the extent of heating in the reservoir. It is also useful to be able to compute the size of the steam zone for cases where thief zones take most of the injected steam. This paper presents a fairly straightforward method of estimating the steam zone developed in a preheated formation, based on certain simplifying assumptions. Some cases of steam injection into a reservoir at its original temperature have already been considered elsewhere.1-3 Because it is difficult or impossible to obtain an accurate representation of the temperature distribution in the reservoir some time after initial heating has taken place, in this work, a linear temperature profile in the cap and base rock is assumed (Figs. 1A and 1B). The linear profile has the advantage of yielding heat flow equations that

Jan 1, 1969

By R. C. D. Phillis

The management of critical resource inventories is an important productivity lever and a significant risk factor?risk in the sense that poor resource availability lends itself to disempowerment of workers, unsafe work practices, wasted spending (high unit costs),and poor quality of work (including mining waste/rework). Most underground platinum mines experience lost blasts that directly lead to reduced productivity. In most surveyed shafts, 30% of lost blasts can be attributed to shortages of critical material and/or equipment. The problem is prevalent despite the existence of conventional transitory surface and underground stores. This paper discusses the introduction of buffer stores as a complementary materials storage system in order to improve health and safety in mines as well as reduce lost blasts. Both quantitative and qualitative results have shown that buffer stores result in dramatic improvements in productivity and are readily acceptable by stakeholders. Keywords Buffer stores, lost blast.

Jan 1, 2011

The material presented in this paper describes experimental work to determine the effect of variations in suction nozzle design upon inlet flow conditions. Four entrance profile shapes were examined under controlled conditions of slurry flow and it was found that the straight ended nozzles had consistently higher entrance losses than the straight taper or the ellipse, and that the circular arc profile nozzles were the most efficient. Subordinate considerations were the measurement of the quantities and the forces involved.As the work progressed, three distinct phases in the pattern of flow were apparent and the static pressures in each were carefully examined. An inlet zone was found to be unstable in changing boundary conditions, a transition zone was largely independent of slurry density and in a zone of stability the pressures were found to be directly related to the characteristics of the flowing pulp. In this zone pressure measurements were reproducible within ± 2 per cent regardless of changing boundary conditions.The effect of varying the "1" parameter of nozzles with a part circular entrance profile was examined and it was found that flow conditions approaching the ideal were obtained when the radius of curvature was between 0·40 and 0·550.

Jan 1, 1966

By John H. Wright

The United States Antarctic Program (USAP), through its principal support contractor Raytheon Polar Services Co. (RPSC), has recently completed a three-year project comprising nearly 936 m (3,071 ft) of undersnow utility tunnels at Amundsen-Scott Station, South Pole, Antarctica. The tunnel serves the new station facilities that are currently under construction. It houses the piping that conveys fresh water from current and future water well sites, as well as waste water to repositories in abandoned wells. The undersnow tunnels permit year-round access for system operations and maintenance. The network of tunnels is entirely unlined and unsupported. And, for the most part, it maintains a rectangular cross section of 1.8-m-wide x 3-m-high (6 x 10 ft).The tunnel runs from 6 to 14 m (18 to 45 ft) below the surface. Eight 1-m- (3.3-ft-) diam raises bored from the surface serve the network as emergency escapeways.

Jan 1, 2002

By S McKinley, S Juras, E Uludag

More and more, today’s mining geologists are asked to identify and create 3D value domains for multidisciplinary usage: grade definition, geometallurgical performance and geotechnical characteristics, to name a few. Often, that domain shape is the result of an assumed or conjectured value as a surrogate to a set of conditions (eg kaolinite-rich, sericite alteration). Would it not be instead better to create the respective domain through identification of a consistent quantifiable geologically-based pattern as its basis?Critical to the identification of patterns is the transformation of 3D point data into a model by a method that uses few, if any, preselected thresholds. Too often we complicate the reviews of the modelled data by prejudging the value range of interest. And when we do revert to 2D views (ie sections and plans), we tend to only examine numbers or line traces. These hinder and obscure identification of geological patterns particularly in deposits of complex geology. Instead, these data should be looked at with minimal prejudgment and interrogated in 2D space by one of the best and most eye-catching display types: filled contour plots.Here we present two different processes that transform data with minimal preselection into formats that allow for pattern recognition by filled contour plots. These are: probability assisted constrained kriging (PACK) and multiple interval interpolant formation (Aranz Geo’s Leapfrog® software). The former creates a 3D model of probabilities on a threshold value; the latter creates numerous (=10), regularly-binned 3D interval interpolants. The results of each method are examined as filled contours over numerous sections or plans. Any distinct patterns are quickly discerned thereby readily identifying the best value to base the creation of a domain. These processes therefore provide a way to marry recent advances in software tools with what is supposed a geologist’s core skill: pattern recognition.CITATION:Juras, S, McKinley, S and Uludag, E, 2017. Pattern recognition in transformed data – the search for domain shapes in mine geology data, in Proceedings Tenth International Mining Geology Conference 2017, pp 37–42 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 20, 2017

By David L. Shuck

This report was prepared for the Bureau of Mines to describe the current methods of design, construction, and development of wells for in situ leaching of uranium. The discussion includes the alternatives for well design drilling equipment and fluids, grout formulation and emplacement, well integrity testing and repair, and well development and stimulation. Current practice in these areas was determined through interviews with eight operators of commercial scale in situ facilities and is also discussed. Based on this information plus the authors' experience, recommendations are made regarding well design, construction, and development tor in situ leaching.

Jan 1, 1982

CONTENTS.IntroductionAcknowledgementsDescription of MineVentilation of MineOrganisation of Fire Fighting SquadsTraining of Fire Fighting SquadsRescue WorkFire Fighting and Rescue EquipmentFire AlarmsConclusionINTRODUCTION.This paper should be read in conjunction with that by R. P. Hooper, entitled "Underground Mine Fire Prevention at the South Mine," Broken Hill. Contents of the paper have been arranged similarly for easy reference. The methods used in educating employees in the use of Proto apparatus remain basically the same, but many changes in the methods and equipment used in subjugating fires have been brought about by the practical experiences gained by officers of the company in extinguishing the outbreaks which occurred in the latter half of 1944.Three fires took place during this period, the first in July, on M.L. 11 in openings leading to timbered workings previously worked and subsequently abandoned by...

Jan 1, 1946

By P N. Holtham

As part of a long-term study of titanium minerals processing being undertaken by the Julius Kruttschnitt Mineral Research Centre (JKMRC), techniques have been developed to measure the electrical properties of the various minerals. The measured values will be used to model the behaviour of the various minerals in high-tension roll and electrostatic plate separators. The resistivities of ilmenite, rutile and zircon from a number of Australian producers have been measured by applying a DC voltage across a test sample and measuring the resulting very small current flow. By appropriate design of the measurement cell and attention to the experimental procedure, reproducible resistivity values have been obtained, ranging from 106Ωm for ilmenite to 1013Ωm for zircon. However, the conditions of measurement are radically different from those under which electrical separation takes place. It is not certain that the measured values reflect the resistivities seen under high-tension separation, during which the particles are subject to a high intensity corona field. Consequently, an alternative technique for measurement of resistivity under conditions of corona bombardment has been developed. It is based on the experimental procedure of Castle and Yelle (1979) used to measure the resistivity of fly ash under the conditions occurring in electrostatic precipitators. This paper describes the development of the segmented ground plane measurement surface and a high-voltage switched resistor network which comprises the in situ resistivity apparatus. Results are presented comparing the measurements made under corona bombardment with those made using the DC measurement cell. The equipment has also been used to study the current distribution from a corona wire, as a function of high-tension voltage and wire-to-plane spacing.

Jan 1, 2001

By W. A. Dunkley, W. W. Odell

About two-thirds of the manufactured gas supplied to the public by the gas plants in the Illinois district is cnrbureted water gas. The leading generator fuel is coke, ma.de in by-product c.oke ovens or in retorts, chiefly from eastern gas coals. During the fall and winter of 1917-18, when the demand for coke by war industries and the restrictions of the Fuel Administration in connection with the transportation of coke from eastern States made it almost impossible for many gas companies to obtain their coke requireml'nts, several water-gas plants had to use bituminous coal as generator fud. Many operating difficulties were encountered, some of which were solved more or less satisfactorily in different plants. A number of plants attacked the problem rather blindly because facilities for making tests were lacking and because technical men were too busy with labor and supply problems to study thoroughly the conditions involved or to ascertain what other plants had done with this fuel. It was therefore with the hope of assisting the gas industry during this critical period, and of promoting the use of Central District coals for gas making, that the Illinois Mining Investigations, a joint agency of the U. S. Bureau of Mines, the University of Illinois, and the Illinois Geological Survey Division undertook the, tests discussed in this paper. • This report was compiled under the auspices of a technical committee appointed by Gov. Frank 0. Lowden to promote the use of Central District coals in gas manufacture as a war measure. This committee included the following representatives of the various agencies concerned: U. S. Bureau of Mines, E. A. Holbrook and W. W. Odell; Illinois Gas Association, C. W. Bradley and R. B. Harper; University of Illinois, Dean C. R. Richards, Prof. S. W. Parr, and Prof. H. H. Stoek; State Geological Survey Division, F. W. De Wolf, G. H. Cady, a.nd W. A. Dunkley. F. W. De Wolf was chairxnan of the committee and E. A. Holbrook was secretary.

Jan 1, 1924

By C. Marais

The use of machine vision in the monitoring and control of metallurgical plants has become a very attractive option in the last decade, especially since computing power has increased drastically in the last few years. The use of cameras as a non-intrusive measurement mechanism not only holds the promise of uncomplicated sampling but could provide more consistent monitoring, as well as assistance in decision making and operator and metallurgist training. Although the very first applications of machine vision were in the platinum industry, no automated process control has been developed for platinum group metals (PGMs) as yet. One of the reasons is that to date froth features could not be related to key performance indicators, such as froth grade and recovery. A series of laboratory experiments was conducted on a laboratory-scale platinum froth flotation cell in an effort to determine the relationship between the platinum grade and a combined set of image features and process conditions. A fractional factorial design of experiments was conducted, investigating 6 process conditions, namely air flow rate (x1), pulp level (x2), collector dosage (x3), activator dosage (x4), frother dosage (x5) and depressant dosage(x6), each at levels. Videos were recorded and analysed to extract 20 texture features from each image. By using artificial neural networks (ANN), the nonlinear relationship between the image variables and process conditions and the froth flotation grades could be established. Positive results indicate that the addition of image features to process conditions could be used as sufficient input into advanced model based control systems for flotation plants. Keywords Flotation, machine vision, image analysis, neural networks.

Jan 1, 2011

By Georgia J. Lysay

The Kemess Mine tailings impoundment is retained behind an earthfill and rockfill dam that, when complete, will measure about 140 m in height with a crest length in excess of 1 km. Due to weak foundation conditions, the dam must be raised at a very flat downstream slope approaching 7H:1V. This requires an enormous volume of fill to construct the downstream shell of the dam, which has a low permeability clayey till core and is raised via the centerline construction method. For the initial years of annual dam raising, from 1996 through 2002, the downstream shell of the dam was constructed with non acid generating waste rock from the open pit, 7 km distant and requiring an uphill haul with obvious cost implications. To reduce costs, and to reduce waste haulage constraints on mining schedules, feasibility studies were initiated for raising of the downstream shell using cycloned tailings sand as opposed to open pit waste. This required inclusion of flotation cells for removal of residual sulphides from the tailings to produce the non acid generating product mandated for the downstream shell of the dam. These studies were positive, and cycloned sand construction was initiated in December of 2002. This paper describes the experience gained with cycloned sand construction for the dam. Unique aspects include environmental controls given the sulphide-bearing ores, preparation of the existing shell of the dam for subsequent placement of hydraulically placed cycloned tailings sand, on-dam settling ponds, water management issues, reclamation of the sand dam for erosion control commensurate with the wet climate, and use of the system to construct an above-water beach of non acid generating tailings to increase the closure security of the structure. A particularly unique aspect of the Kemess experience is hydraulic fill operations extending throughout the coldest winter months, as compared to other operations where such placement has traditionally been considered non-viable through the winter months

May 1, 2007

By Ernest J. Conway

This report presents engineering drawings for six material handling devices for underground coal mines. The devices were designed under a U.S. Bureau of Mines program to reduce injuries from material handling during mine and equipment maintenance. The six devices are (1) scoop-mounted 1411: boom, (2) swing-arm boom, (3) heavy-component lift-transport, (4) mine mud cart, (5) container-workstation vehicle, and (6) timber car. Each device is described briefly, and recommendations are made concerning the design of new devices.

Jan 1, 1989

While the United States and the rest of the world struggles with record-setting oil prices Canadian oil sands producers are ramping up production to meet demand for oil while also fighting against a host of negative images. In recent months, the price of oil has skyrocketed. Most of that oil comes from Saudi Arabia. In Alberta, Canada there are unconventional oil reserves that rival those in Saudi Arabia in the vast Canadian oil sands, sometimes called the tar sands. Proponents of the oil sands say that Alberta?s oil sands can be a secure source of oil and energy for the United States for many years to come. With new mining and drilling projects, the industry has said that it could quadruple its production to nearly 4 million bbl/day by 2020. Time magazine once called the oil sands, ?Canada?s greatest buried treasure that could satisfy the world?s demand for petroleum for the next century.? So why hasn?t the United States embraced this close, politically secure source of energy? Because, getting usable fuel from the oil sands can be a dirty business, say opponents. The oil sands are a combination of clay, sand, water and bitumen. It is a heavy, black, thick oil. Oil sands can be mined and processed to extract the oil-rich bitumen, which is then refined into oil. The bitumen cannot be pumped from the ground in its natural state. Instead, tar sand deposits are mined, usually using strip mining or openpit techniques, or the oil is extracted by underground heating with additional upgrading. These methods require a huge amount of energy and water and produce a large amount of carbon emissions. Environmental groups that have long spoken out against the oil sands projects got some political backing in the United States in June when a group of mayors from large U.S. cities spoke out against the oil sands, as did presumptive Democratic candidate for U.S. president Barack Obama?s senior energy advisor. During a convention of large-city mayors in Miami, FL, Alberta?s oil sands were singled out in a nonbinding resolution calling for national guidelines to track the lifecycle impact of different types of fossil fuels. The resolution urges cities not to use unconventional sources of energy with a large carbon footprint, such as liquid coal and oil shale and oil sands.

Jan 1, 2008

By Robinson KJ

There has been much debate in recent years regarding the number of Geology (Earth Science) graduates produced in Australia. The key variable has commonly been assumed to be the placement of graduates in the mineral and petroleum industries. Although not wishing to deny the importance of this element, we contend that Geoscience studies should be given to a wider variety of graduates. The essence is to make students and future citizens more environmentally aware. INTRODUCTION Geoscience is fundamental to exploration and to the well-being of the minerals industry and hence the Australian economy. The value of mineral primary products exports for the past three years has been: 1895 $15.3 billion 1986 $14.8 billion 1987 $16.3 billion (Data source: B.M.R) The mining industry supplies about 40% of Australia's export earnings. However the overall value of Geoscience to the Australian economy is much greater. At the opening of the ANZAAS conference in Townsville during May 1987, Sir Bruce Watson , Chairman of the Mt. Isa Mines Ltd., made a plea for a national re-examination of the way science is taught in secondary schools. In particular he emphasized the point that the community should be more aware of the importance of Geoscience and the value of the mining industry to Australia.

Jan 1, 1989

By Reno H. Sales

Our colleagues cannot in the future earn reputations and medals for achievements in milling and smelting ore and for successful management of mining companies, if some one doesn't keep finding and mining the ore to mill and smelt and to provide the basis for the good management. Good ore seems sometimes to be quite helpful to good management, and good ore is not as easy to find as it used to be. And there are still more reasons, why—when this honor had been decided upon and named for Mr. Daniel C. Jackling—it should be initially conferred on Reno H. Sales. . The terms of reference of the award are that it should be conferred upon an individual working in the fields of mining, geology, geophysics, who has made an outstanding contribution to the progress of technology in one or more of those fields. And in this initial year (the earlier years are the easiest) just that was done. I think I could get away with it amongst the old-timers of my generation if I say that this time they made the award to the individual, who made the outstanding contribution. But, as Al Smith used to say, "Let's look at the record." Really, the record is mixed up a little with extra-lateral litigation—the old-time "apex cases" under Section 2322 of the Revised Statutes. Reno Sales doesn't like such litigation, but there is little question that the urgency, generated by conflicting claims of intra-limital and extra-lateral rights, and consequent necessity for committing to records and maps the complications of Butte structure, did advance—and by several years—the first continuous, accurate, systematic, and scientific portrayal of the geological and mineralogical details of what is, after all, the most important and the most complicated copper district—at least in North America. Prior to Sales' time, some of the most eminent of geologists often waived details. One geologist took the judge to the window to show him the Rarus fault going through a notch in the Continental Divide. The entertaining testimony in the Bluebird litigation was as perfect in literary style as it was innocent of the criteria by which faulting and lack of continuity of vein structure are now recognized. At any rate, this need for an accurate record of structure was in the background—to whatever extent it was, or was not, the etiological agent—for formation of the Geological Department of the Amalgamated Copper Co. in and about the year 1900. Charles W. Goodale was at that time the head of the Boston & Montana, and John D. Ryan succeeded William Scallon as the president of Anaconda Copper Mining Co. in 1905. Horace V. Winchell, for years a specialist in extra-lateral litigation, was perhaps the man who at that date had the vision, the persuasive weight with the management, and the willingness to defend the idea of large current expenditures (as then viewed) for a complete and sys-

Jan 1, 1955

By Clements R. J, Davey J. M

Development of the process from the pilot stage to the current operation of the Capel, WA plant is briefly described.The design criteria for a larger sized plant are discussed together with factors that relate suitable feedstocks and coal types to the capital cost, capacity and product grade of future plants at locations other than Capel. The application of the process to the direct reduction of iron ores is briefly discussed including its commercial application at Rockwood, Tennessee.

Jan 1, 1980