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By Randall M. Wheeler

Many of us have used a seismograph to measure peak particle velocity and frequency. But do we really understand why? Also, why do we measure particle velocity instead of displacement and/or acceleration? What is the vector sum? How do these items relate? Where does frequency fit in? This workshop will attempt to answer these and other questions. Some of the answers may surprise you, others may not.

Jan 1, 1997

There are many compelling reasons why correct sampling schemes should be standard practice in the mining industry, yet there are numerous examples where poor sampling practices are known to exist in the business yet permitted to continue. It is not just technical issues that can be ascribed to the reasons for the continued use of incorrect methods. This paper proposes non-technical reasons why incorrect sampling practices continue, and identifies potential ways to overcome them.

Mar 1, 2010

By John C. Didlinger

How do you measure the highwall? Why do you even need to know the highwall measurement? Why is it important? The importance of this measurement is to help keep a level floor and to help control vibration. Nevertheless, since most of us are not mountain climbers, there must be a safe and easy way to make an accurate highwall measurement. So with these factors in mind, how do you make your measurement?

Jan 1, 1997

Richard Moldenke, New Pork, N. P. (communication to the Secretary*):—Iu following the discussion of the specifications for cast-iron and finished castings, I mas strongly impressed with two points which might be ventilated to advantage more fully from the view of the practical foundry-man. First, the reasons why only silicon and sulphur were specified and not phosphorus, manganese and carbon; and second, why but little was said concerning the presence of iron oxide in the material.

Jan 1, 1905

By S. J. Benson

The Harts Range deposit, owned by Olympia Resources is located some 130 kms northeast of Alice Springs, in central Australia (part of Australia’s Northern Territory). The core economic minerals here are industrial grade garnet and alumino magnesio hornblende (AMH). The resource contains an estimated 2.3 million tonnes of recoverable garnet and 6.2 million tonnes of recoverable AMH, making Harts Range one of the most significant abrasive medium deposits in the world. Part of the general marketing axiom of Olympia Resources is to make high quality products from the garnet and also a special series of blended garnet/AMH products to match the needs for other sectors of industry. The deposit mineralization is of alluvial origin and thus, requires no significant liberation regimes. Over 50% of the head feed is in the form of SiO2/quartz and as much as 17% is –63micron clay slimes and mica. Original pilot scale testwork for flowsheet development centred around fairly conventional wet gravity systems, with spiral concentrators being the pre-eminent separating device. To a point, this type of flowsheet was going to achieve some of the aims albeit fairly predictably. The one area that this circuit would be very limited though is in the recovery of the very coarsest of the medium SG minerals. This was going to be a very important and longer-term costly flaw. Amongst the highest demand, greatest value of products to be produced will be the range of garnet & AMH in the +600 microns sector. A flowsheet dominated by spirals would be fated to forfeit a significant proportion of these coarse minerals to tails. At the Outokumpu Technology P/L test facilities in Perth, testwork was conducted using a pilot scale Floatex® Density Separator, the LPF-230 model. Using a twin stage approach, whereby a primary Floatex® underflow reports directly to a secondary Floatex®, recovery of the economically important +600 micron garnet was increased from 65% in the spirals-only flowsheet to 95% using the Floatex® based flowsheet. Finally, the other significant aspect of this approach is in substantial simplification of the circuit required and a huge reduction in plant footprint. Also, the nature of using hindered settling provides substantial opportunities for process control and automation.

Jan 1, 2005

By Stephen C. Everett

Why? This is the first question that everyone asks. Why did Renison give away such a valuable asset? What is the problem with Mt Lyell? No doubt this question was asked of Denehurst regarding Woodlawn, MPI at Stawell, Golden Shamrock at Cobar, Western Metals at Cadjebut and Poseidon with the Big Pit. Whilst it is not possible to second guess the rationale behind Renison's strategic withdrawal from an operation that they considered to be uneconomic, the Renison/Mt Lyell deal has certain specific perspectives:

Jan 1, 1995

By R N. Humphries

The aim of this paper is to question the need to develop bespoke monitoring and assessment methodologies and criteria, thereby ‘reinventing the wheel’, when designing and assessing the success of important natural habitat and ecosystem restoration schemes at mine sites in the UK and Australia. It draws attention to the existence and applicability of the Phase I Habitat, National Vegetation Classification (NVC) and Condition Monitoring methods in the UK and similar approaches used in Australia. These are long accepted established methodologies and have published accounts for describing, assessing and managing natural vegetation communities, habitats and ecosystems. They are often used at the environmental impact stage, but seemingly rarely, if at all, in restoration design and management at mine closure. Their application to mine restoration and closure is illustrated and discussed by reference to a surface coalmine in South Wales, UK.It is concluded that the application of a combination of the Phase I Habitat, NVC and Condition Monitoring methods is highly relevant to the expectations of the Convention on Biological Diversity (CBD) and its implementation in the UK, and probably in Australia too. The methodology and criteria described could be incorporated into the guidance and specified in the mining permits so that there is clarity as to the expectations and requirements for monitoring and assessment for bond release. Their use could be of wider application where there is a requirement to assess the success of restored CBD assets and ecosystems.CITATION:Humphries, R N, 2014. Why reinvent the wheel when there are established methodologies to aid the design and assessment of restored natural ecosystems on mined land?, in Proceedings Life-of-Mine 2014 , pp 675–692 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 16, 2014

By Robert F. Baker

Neanderthal technology is a harsh and inaccurate way to describe modern underground construction and mining practices, but such an exaggeration helps to focus on a major problem or wasted opportunity of modern society. Why is it not safer to excavate in the underground? Why are the working conditions still so unfavorable? Why are urban freeways, shopping malls, warehouses, power plants, sewage disposal treatment plants, and similar facilities still constructed on the surface of the ground--because it is a better location? On the contrary, if underground technology made full use of existing knowledge, underground resources and space would be much more effectively used. And why is the technology so inadequate? Certainly, researchers and practitioners are aware of the shortcomings and are equally aware of problems that have to be overcome. One of the most important reasons has to do with the type of policy goals that society has set in the past. Policy makers may have agreed that improvements would be desirable but no serious commitments have been made--that is, there has been no major allocation of resources to advance these technologies. And yet, to bring about significant changes will require significant time and resources. The resources that are needed are far in excess of what industry can afford to invest, particularly since the pay-off may be far in the future. So the problem reverts to society in general. As long as society is willing to tolerate the present costs and safety requirements for recovering minerals and for constructing underground facilities, then the changes will be slow in coming. Until such time as society sees and desires the benefits

Jan 1, 1974

Extensive personal experience in the USA and Australia has shown that Australians working in suitable work environments are capable of world-class performance. To build such work environments, mining leaders need to ditch two common management approaches that have not succeeded. Firstly, stop relying on traditional methods of trying to change people's behaviour simply by using communication alone to change attitudes and then change behaviour. Analysis of human behaviour explains why this approach fails in all industries. Secondly, stop trying to improve productivity by just running harder and increasing capital investment. Understanding work processes explains why this approach has limited success.

Jan 1, 1995

By George T. Hansen

WHY try to find oil in Utah? Why try to find oil anywhere? Isn't there too much oil already? Answers to these questions involve general oil conditions but are pertinent to my subject. In the first place oil produced in Utah up to the total amount of local consumption would not be subject to nor concerned with the national oil situation. An oil field in this State capable of producing up to 15,000 bbl. per day would have a large value and prompt realization. In the sec¬ond place, there is not too much oil nationally although the markets have been upset temporarily from time to time. Petroleum is so necessary and is in such general demand that an oil field anywhere, anytime, is a valuable and live asset. The oil business in general shows the best condition of any major industry. It has never been hit as hard as most industries and 1932 was a large improvement over its low spot of 1931. It can be and probably will be the one to lead the country back into business stability. Consumption of its products has been reduced less than that of any other important commodity. There are good and valid reasons why it should have been making a normal profit continuously. It has the oil and the processes and the facilities and the policies and the consumption of its products. There is only one reason why it has not been profitable recently and that is the lack of intelligence of from five to ten per cent of the producers. An op¬erator lacks intelligence when he cannot see that it is better for him to sell one barrel of oil at $1 than two or three barrels at 25 or 35c. per bbl.

Jan 1, 1933

By Kirk Nobis

Develop a Risk Management Plan for Your Mine ? Why? ? Measuring ? Managing ? Conclusion

Jan 1, 2006

By Sidney Snook

FLUORSPAR production is the most important industry in a compact area in southern Illinois and western Kentucky bordering the Ohio River. Producers' activities do not usually figure much in the mining news of the country, so that few know that the last year or so has been an unusually active one. Mine shipments more than doubled in 1939 compared with the poor year 1938. The average price changed but little, though it is now about one-sixth higher than at the beginning of last year. The outbreak of war in Europe a year ago lent an immediate stimulus to the industry, though only about 15 per cent of the domestic consumption is normally imported, thanks to a tariff of $8.40 per ton, equivalent to about 30 per cent ad valorem. Be- cause of the increased production and many expansions and improvements in the mines and plants, the period since the beginning of 1939 has been the most important one for the industry in the last 15 years.

Jan 1, 1940

By John W. Padan

The 1982 United Nations Convention on the Law of the Sea contains major provisions that U.S. negotiators have sought for over two decades. The internationally recognized right to the mineral resources of a broad continental margin is of potentially enormous future importance to the United States. Although water depths reach 10,000 feet in some of the deeper areas of the margin, technology is rapidly making those depths economically accessible. In 1997, production in the Gulf of Mexico will reach a world record water depth of 5400 feet. Of perhaps even greater importance to the oil and gas industry is the broadly acknowledged right for tanker transport of oil to take place throughout all parts of the world's oceans.

Jan 1, 1996

By T. E. Schwarz

The publication of the report by Mr. F. L. Ransome1 was welcomed by many engineers who had mined in the heart of the San Juan country, braved its long and snowy winters, climbed its lofty peaks, run the gauntlet of its snow-slides, and studied its problems of geology, while making dividends for their English or American clients. This report helps one to understand why the bonanzas occurred, and why the inevitable " borrasca " presents itself where least expected. The Red Mountain district of Ouray county, a very productive section from 1884 to 1893, occupies considerable space in the report mentioned. The character of the ore-occurrence.

Jan 1, 1906

By Phil Dakin, Rajiv Chandramohan, John Lo Grande, Greg Lane

Crushing and grinding circuit availability is a critical design factor defining the installed equipment selection and the process buffers required to maintain throughput during maintenance. The comminution circuit typically accounts for a process plant’s largest capital expenditure and energy use. Effective process and equipment selection and layout optimization are crucial steps when combining the objectives of cost-effective design and high circuit availability in operation. This paper outlines fit-for-purpose design principles for optimizing process flow, eliminating standby equipment and reducing buffer residence time whilst improving maintainability and operability.

Feb 1, 2025

By L. Hagenbuch

Off-highway truck purchasers know the amount of tonnes, pounds, kilograms, etc, a truck will carry. However just because a truck is rated at 240 tons may in no way correlate to what that truck will actually carry. Two numbers define the carrying capacity of an off-highway truck: 1. The weight carrying capacity of the truck; 2. The volume carrying capacity of the truck. These two numbers must be in sync or the amount of payload carried will vary from the carrying capacity of the truck. Currently the Society of Automotive Engineers (SAE) standard J1363 January 1985 defines the volumetric carrying capacity of an off-highway truck. However as is well known in several South American countries, the SAE standard overrates the truck’s effective volumetric carrying capacity 15% to 20%. This paper presents a method for measuring “effective” body volumetric carrying capacity, resulting in a truck body for carrying the targeted load, matched to the loading equipment that interacts positively with the truck chassis.

Jan 1, 2002

By Augustus Locke

WHY should I, a geologist, be coming before you to talk about finding ore? Certainly, the great discoveries of the past have not been made by geologists, but by men of very different tastes and training. If, in the year 1800, the course of ore discovery could have been foreseen, there would have been no reason to put it into the hands of geologists or other men of technical preparation. It was not geologists but explorers, Indian fighters, prospectors, manual laborers, and hardy financiers, who initiated the American mining industry. Then why this association of geological technique with ore finding? Why this feeling that the way to find ore is to apply to the problem what we call geo- logical principles? Well, to put it broadly, the old method has run out on us. It no longer works. Or, to put it another way, the cost of finding ore by the old method has mounted so high that one old district after another has become, practically speaking, dead, and various other old districts that are still going apparently at full strength are actually beginning to limp, and, with the cost of discovery mounting yearly, to fear, more than they will acknowledge, that the end is approaching.

Jan 1, 1926

By Rayleen Riske

Why do we look for better reconciliation when times get tough? Why wait? Mine reconciliation should be a priority throughout the good times too. In fact, with good reconciliation, those good times are going to be even better and will help pave the way to success through those preventable bad times. Reconciliation throughout the entire mining value chain requires the capture, validation, and analysis of copious amounts of data. This task can be daunting for a team in a small mine, let alone reconciling across a suite of large mines. This paper will outline the different ways we can reconcile across the value chain, why we should reconcile over differing periods of time and how Snowden?s solution to proving reconciliation can be a simpler, reliable and transparent process. Snowden?s Reconcilor is proving to be a valuable tool on any mining scale, by capturing, validating, sorting and reporting data for timely decision making by the site geologist through to corporate management. By instigating vigorous reconciliation, you are setting your mine up for the future. Not only will you have the means to analyse your current processes and measures, but you will have the opportunity to identify and improve your mine?s performance from the resource model through to the final product.

May 1, 2010

By Frank Rausche

Why testing What tests can be done Dynamic load testing Loading device Measurements Analysis Examples

Jan 1, 2001

Mining Automation By Professor Hugh Durrant-Whyte, Australian Centre for Field Robotics and Centre for Mining Technology and Equipment, Department of Mechanical and Mechatronic Engineering, The University of Sydney Professor Hugh Durrant-Whyte summarised why the mining industry needs to automate and reviewed the current automation technology - its risks, costs and benefits. Why automate? The drivers for automation include: safety, productivity, quality control and reduced manning, equipment utilisation, maintenance, and organisation and planning. Durrant-Whyte recommended starting out with a picture of a fully automated mine and working backwards through a systematic analysis of benefit and risk. This also involves looking at the impact of the total automation on current mine design, and identifying the key technologies.

Jan 1, 1997