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By G. B. Shea

"INTRODUCTION Much of the recent progress in increasing the efficiency of oil-well performance can be attributed to advancements in the art of cleaning wells. Through research and development by operators and service companies during the past decade, significant improvements in the application of engineering and chemical principles to well-cleaning technology have widened greatly the scope of ""clean-out"" methods to the end that greater ultimate recovery of oil will be attained.This report reviews recent improvements and developments on this important problem in California; it describes also the use of various methods and tools for cleaning wells to stimulate or revive their productivity. Developments in preventing and removing mud sheaths in well-completion operations also are described. The report is based on a field survey, supplemented by data from the technical and patent literature and from manufacturers' catalogs, which contain much valuable information.In preparing the material for publication as a Bureau of Mines report, the author has been fully aware of certain limiting conditions that attend the discussion of a subject such as that treated in this report. The following are examples:1. To a considerable extent, well cleaning in California is done with tools rented from service companies, and their representatives and employees are specialists in jobs of this type. They usually have working experience with their own equipment and methods which greatly exceeds that of persons whose interest has been casual or who have had no opportunity to study the subject in detail in actual practice. Many of the tools and methods are covered by letters patent for the protection that may be in developing and successfully applying these mechanical and chemical means of increasing the production of wells. Frequently several years have been required to perfect a given tool or technique, requiring relatively large investments to establish a service that is remunerative to those who have primary interest in a certain development and at the same time attractive enough to the operators of producing properties (because of greater quantities of oil delivered into the flow tanks) to warrant employment of or contractual agreements with a particular service group."

May 1, 1943

By Brooke Clements

The Buffalo Head Hills region is located approximately 350 kilometres northwest of the city of Edmonton in northcentral Alberta (Figure 1). The Alberta diamond joint venture consisting of Ashton Mining of Canada Inc., Alberta Energy Company Ltd and Pure Gold Minerals Inc. began exploring for kimberlites in the Buffalo Head Hills region in late 1996. At the time, the Mountain Lake diatreme, located 200 kilometres to the southwest, was the only reported kimberlitic rock in Alberta (Leckie et al., 1997, Figure 1). Exploration efforts since 1996 have successfully identified a new diamondiferous kimberlite province in Canada.

May 1, 2001

By A. Robles-Vega

Personnel of Mexicana de Cobre, a subsidiary of Southern Copper located in Nacozari, Sonora Mexico have been working in the past few years on the development of a process to treat and manage, in an environmentally accepted practice, the residues and effluents generated during the process. To date, this team has been reviewing existing technologies and also has explored new alternatives. At the end of this phase, a novel, efficient and complete process has been configured which will be able to treat some solid and liquid streams such as Teniente converter dust, Peirce Smith converter dust, a Sb-rich precious metals slag, copper refinery electrolyte bleed, acid plant blowdown and an acid bleed of the precious metals plant. The process will consist of a leaching stage, followed by a very selective copper precipitation using novel technology which has been named as back reactions. After copper precipitation, impurities (As, Sb and Bi) will be precipitated mainly as arsenic trisulfide (As2S3) using H2S(g) which will be generated by means of a new process developed in our company. At the end of the process, small volumes of arsenic trisulfide will be vitrified and then disposed as a stable residue.

Jan 1, 2007

By G. L. Smith

The fundamental challenge facing mineral and metal companies is how to create sustainable value while operating within mandated strategic bounds, identified constraints, and variable market and economic conditions. This can be achieved by allowing the fixed physical nature of the mineral asset to drive definition of the optimal technical solution to mining and processing activities, and developing and resourcing a strategically aligned portfolio of production entities that creates flexibility to near- and longer-term business environment shifts, i.e. a production mix that allows variation of output to respond to short term market variation, within a long term context. The practical achievement of this outcome is enabled by the concept of strategic long term planning. The core elements of strategic long term planning in the metals and minerals industry, and the relationship between them, are expanded. The strategic long term planning framework is a logic construct that enables delivery of an optimized, strategically-aligned business plan from the mineral asset portfolio using a set of tools and techniques with a common language, standards, systems and processes to align decisions and actions on a cyclical basis.

Jan 1, 2012

By Arpad E. Torma

The identification and characterization of lithographic iron and sulfur oxidizing bacteria in the 1940' s. opened up new possibilities and challenges for the mining and metallurgical industries. These were exploited during the 1950's and' 1960's, when it was demonstrated' that mining wastes and complex unused mineral resources could be economically treated by bacterially assisted heap and dump leaching processes?. During the 1970's this technology grew into a more structured discipline called "biohydrometallurgy". In the l980's efforts were devoted to the identification of a variety of organisms involved in naturally occurring leaching processes. Further efforts dealt with the elucidation, of leaching mechanisms; the leach ability of nickel, coban, zinc, and precious metals; the desulfurization of coal; and diverse biosorpion phenomena. The application of genetic engineering techniques for the improvement of microbial performance was also initiated?. Current trends in biohydrometallurgy include improvement of many of the techniques noted above, as well as application of leaching. technolog.ies to. environmental remediation scenarios. These activities afford considerable opportunities for research in the 1990's. For example, bioremectiation of abandoned mining and processing sites requires development of new and economically viable technologies capable of removing low concentrations of toxic metals from high volumes of solid and/or liquid wastes.

Jan 1, 1991

By André Laplante, Robert C. Dunne

"The role of flash flotation in precious metal recovery is reviewed. Interacting flash flotation and gravity recovery is discussed. The GRG test can be used, when linked to the behaviour of gold in grinding and classification units, to predict the recovery of GRG by flash flotation. The Cadia mill in New South Wales is used as a case study of circuit design, performance and simulation. It is shown that high throughput coarse grind applications such as Cadia require very effective fine GRG recovery systems in the primary grinding loop, which are more consistent with flash flotation than batch centrifuge concentrators (BCCs). BCCs can effectively recover a significant fraction of the GRG from flash concentrates, as predicted by laboratory testing and confirmed at a growing number of mill sites.INTRODUCTIONThe GRG test was designed to characterize Gravity Recoverable Gold (GRG) ten years ago (Woodcock and Laplante, 1993; Laplante et al, 2000), in response to the need to predict how much gold could be recovered from the main circulating load of grinding circuits using centrifuge concentration. The amount of GRG is not itself a prediction of gravity recovery: the performance of a gravity circuit nested in a circulating load also depends on the type and size of unit used, how much of the circulating load is treated, and how many times GRG is recycled and presented to the recovery circuit. The GRG test was first used in a simulator to predict gravity recovery (Laplante et al, 1995), and indeed most of the early tests targeted ores or prospective ores for which gravity recovery was an obvious match. As the test became more accepted, more and more samples returned a verdict that precluded the use of gravity recovery, or made it marginal. Typically, such ores are either copper-gold or base metal ores in which the GRG content is often fine (largely below 105 um) and ranges from 8 to 33%. Extensive simulation and plant sampling tests, either published (Laplante et al, 1997) or proprietary, show that full scale gravity recovery for these applications is generally below lo%, and can be as low as 2%. Not in all cases are such low recoveries economically unjustifiable, since there is documented evidence (Darnton et al, 1992) that a significant proportion of the gold recovered, at least in the case of base metal ores, would not have reported to the copper or zinc concentrate and received NSR credits."

Jan 1, 2002

By J. Avraamides

Some operational difficulties have been encountered in the transfer of carbon-in-pulp technology to Australian conditions. Many gold mines? are located in remote and arid areas where the available ground water is highly saline. There is a gradual depletion of free milling oxidised gold ore reserves resulting in the necessity to treat deeper primary sulphide .deposits which can be refractory. Some near-surface ore-bodies and tailing dumps are contaminated by natural vegetative matter which can interfere with the adsorption of gold from the cyanided pulp,. Advances which have been? made include potable water conservation in elution, a new type of regeneration kiln, inter-stage screens, alternative leaching systems transportable carbon-in-pulp plants and efficient open-cut mining methods. Academic and applied research is well supported by government and industry and the results are normally rapidly disseminated and put into practice by the gold mining industry.

Jan 1, 1989

By Li Shibo, C. Halls

The compositions of olivine, pyroxene and chromite from the Proterozoic ultramafic complex are analagous to those of cumulate ultramafic rocks of tholeiitic origin, suggesting that the parent magma may have been tholeiitic rather than komatiitic. The complex contains economically significant Ni-Cu sulphide mineralisation. The high sulphide/silicate ratio is best explained in terms of the segregation of sulphides from a large volume of magma, of which all but the ultramafic cumulate fraction has since been eroded. Platinum-group minerals that have been identified include sperrylite, moncheite, native platinum, froodite, merenskyite, michenerite and Pd-rich pentlandite lamellae exsolved from pyrrhotite. They are characteristically found in close association with chalcopyrite, either along the contacts between hydrosilicate and sulphide grains or in cracks within pentlandite and chalcopyrite, which may also be intergrown with galena. Crystallisation from a Cu-rich residual magmatic liquid also enriched in Pt, Pd, As, Sb, Bi, Te, Zn and Pb is postulated.

Jan 12, 1993

By K. Reinhardt

THE idea of burning blast-furnace gases directly in gas-engines, instead of under steam-boilers, as had previously been done, was first put into practice barely ten years ago, almost simultaneously in Great Britain, Germany and Belgium. The pioneers of this movement made their first experiments with small engines. After these experiments had given satisfactory results, and it had been shown that the thermal value of the poor blast-furnace gases, in spite of defective scrubbing, could with safety be directly transformed into mechanical work in the gas-engine, there very soon arose a considerable demand for gas-engines of large power, similar to the large steam-engines employed in metallurgical works. In face of these sudden requirements, the gas-engine builders were placed in a difficult position; for up to that time the gas-motor was considered as suitable for small engines only, and it was generally believed that the limit of size bad been attained with 100 to 150 effective h.p. in a single cylinder. Manufacturers of gas-motors, however, did not underrate the advantages offered by this new field for their manufactures, and it so happened that in Germany the Berlin-Anhaltische Maschinenbau-Gesellschaft, of Dessau, was the first to undertake the construction of a 600-h.p. two-cycle gas-engine, with two cyl¬inders of the Oechelhäuser-Junkers type, for the Hoerder Mining & Smelting Company. The engine was started in 1898, and, with a few improvements and alterations, is still working satisfactorily. This engine worked with astonishingly high of efficiency, considering the period. The builders were therefore

Nov 1, 1906

By Ruy L. Rodrigues

Vale is in the early stages of commissioning its Onça Puma nickel operations. The project is meant for the production of 58,000 tpa of nickel contained in ferro-nickel, substantially contributing to the company?s vision to achieve world leadership in the nickel business. Mineral resources will be exploited from the homonymous deposits in the Midwest of state of Para, Brazil ? some 100 km southwestwards from the company?s Carajás iron ore properties. Resources as of 83 Mt at 1.73 % Ni will sustain a mine life of approximately 40 years. The property was acquired in late 2005 and Vale has since extended the engineering studies and proceeded with the implementation. Nickel will be mined from saprolitic ore at a rate of approximately 10 Mtpa (ore plus waste) in early years ? ramping up to some 15 Mtpa 7 years later ?, to feed the plant at a rate of 2.5 Mtpa. The process uses conventional RKEF (Rotary Kiln Electric Furnace) pyrometalurgical route whereby the ore is homogenized, calcined in rotary kilns, melted in electric furnaces and further refined to ferro-nickel. The plant has been designed and constructed applying the latest available technology, aligned with Vale?s vison to exceed the highest existing standards for environmental control, health and safety and productivity in the industry. Total investments in these operations are anticipated to correspond to USD 2.3 Bi and will materially contribute to the regional development and well being of the nearby communities and other stakeholders.

May 1, 2010

By G. Winkel

Safety conditions in industry have greatly improved over time. However, around the world, in Canada, and in each province or territory, people are still the victims of serious industrial accidents. The increasing safety of people at work then continues to be an imperative in industry today.<p> So how do we achieve a workplace where no one gets hurt? Well, in simple terms, folks need to be protected from unplanned exposures to equipment or energy sources that can do harm. If you think about it, all of our efforts in loss management and safety should then be directed toward avoiding these uncontrolled events. And it works! Our safety performance over the years has enjoyed tremendous improvement due to this support for loss management and safety. We now explore best practices toward achieving that next step in safety improvement.<p> As shown following, a large combination of loss management activities act together to support safety performance. Many of these activities are interrelated and some people have described them as the ?inputs? into an approach or program for achieving safety. Using this description, it follows that the ?outputs? of the program are some of the advertised measures of safety we see around us today, such as injury frequency rates. <p> It is asserted that a leadership focus to regularly measure safety and loss management activites (so-called ?inputs?), as a basis for taking supportive actions to ensure their effectiveness, is the basis for safety results (so-called ?outputs?) that consistently achieve high standards of excellence.<p> The concept of managing input activities, as enabled by effective measurements, can significantly act to transform our focus and priorities in the workplace. Supporting input activities like strategies, plans, or procedures with our best efforts will get us to our intended goals. Tracking outputs alone will not.<p> Safety and production have traditionally been cast as competing objectives. When both objectives are mutually supported and considered, however, people will invent ways of doing work that support both safety and production, and any other business parameter. When done right, innovation through meaningful involvement of affected people in the workplace will support safety excellence in a manner that in turn improves business efficiency overall.<p> For a workplace to be safe, it then requires everyone?s help and participation to make it happen, a collaborative effort by management, leaders, and frontline folks with the power and responsibility to take appropriate action at every level in the organization. In this way, everyone becomes a leader in safety.<p> The achievement of commitment to loss management input activities by folks in the workplace is the basis for attaining safety excellence. A workplace founded on commitment supports a safety culture with a vision for safe work performance at outstanding or world-class levels of achievement.<p> One may ask if injury incidents will be eliminated with this commitment and focus on workplace safety? Well, despite our best efforts in this area, there is never a guarantee that things can?t go wrong. We are simply not perfect. There remains in our workplace complexities and unanticipated risks that can have disastrous consequences if not managed at every moment. And when it goes wrong, we need to know we?ve truly tried our best, and now we have more to learn so we can get even better. <p> That?s the challenge represented by the safety imperative, a challenge to take safety performance that next step, a fulfillment of our commitment to the moral obligation we have to each other?s safety. It?s an effort that will continually raise the bar of world-class safety performance achievement for future generations. It?s a legacy we can be proud to be part of.

Sep 1, 2004

By P. M. Hawley

In April 1975 Kaiser Steel Corporation and the United States&apos; Department of Energy entered into a cost-sharing agreement for the demonstration of shield-type longwall supports on three consecutive longwall panels at Kaiser&apos;s York Canyon&apos; Mine in New Mexico. Under this agreement the Department of Energy supplied 117 Hemscheidt 320 HSL caliper-type shield supports and hydraulic pumps for the duration of the demonstration. The purpose of the demonstration was to educate the U.S. coal mining industry as to the benefits in production, productivity, health and safety, and increased coal extraction afforded by shield-type longwall mining systems and to provide the industry with a working model. A detailed description of this demonstration is given in U.S. Department of Energy Publication No. DOE/ET/12530-T1, entitled "Demonstration of Shield-Type Longwall Supports at York Canyon Mine of Kaiser Steel Corporation," hereafter referred to as the York Canyon Report.

Jan 1, 1984

Misiman society is matrilineal and despite relatively long contact with Europeans and mining, it retains its traditional consensus style of decision making. Many Misimans at least understand English, and this has encouraged comfortable communication between the people and the company (Misima Mines Pty Limited). Company care in monitoring the environment (mostly using Misiman staff), its policy of maintaining a largely Misiman workforce, and its emphasis on training and safety, have all created an environment compatible with Misiman society. In addition, the company has constructed and/or upgraded community facilities such as the airstrip, roads, the health centre, police station and schools, and has actively promoted local business endeavours. All these initiatives have been accomplished by constant dialogue with the largely Misiman workforce, and with the Misiman people, both before and during implementation. Constant, careful communication, using traditional Misiman consensus methods, appears to be the key to continued community acceptance of the project.

Jan 1, 1991

By C. Villaseca, F. Penna, R. Villarroel

Acid mist is the undesired result of copper electro-winning (EW) process, generating a contaminated and hazardous environment in the working areas, as well as promoting high corrosion conditions for structures and equipment in the EW tank-house due to the buoyancy of sulfuric acid in aerosol form. Likewise, organic entrainments that occasionally occur in this process contaminate the cathodes, as well as increasing the risk of fire. LateralVex® and LateralFlow® are technologies that effectively and efficiently solve these problems, without affecting the usual activities of the operators, thus presenting a significant distinction with respect to other technologies that seek to solve these problems. Minera Antucoya, an AMSA group company, which produces 80,000 tons of electrolytic Cu per year, decided to install both technologies for its EW tank-house, LateralVex® in commercial cells and LateralFlow® in scavenger cells to keep both the acid mist and the organic entrainments under control. This paper presents the effects of applying these technologies in Minera Antucoya’s electro-winning plant, the challenges addressed, the difficulties encountered, the problems and opportunities that their implementation involved, as well as the surprising results obtained at the time of measuring the acid mist— less than one hundred’s part of the Allowed Weighted Limit—in samples taken with the plant operating at maximum current capacity. Additionally, the paper includes some of the improvements identified during the period, more than 3 years, in which these technologies have been in operation in Minera Antucoya. INTRODUCTION Electrowinning is the most used electro-chemical process in the hydrometallurgical industry for the recovery of highly pure metallic copper as its final product, which is formed in previous stages in an aqueous medium that goes through a selective process using organic solvents to separate impurities and concentrate the metal in a sulfuric acid solution. In the last stage, this solution goes through a process in which high- density current at a low voltage is applied, so that the metal in the solution will deposit in solid state on a plate, usually a stainless-steel plate. This last process involves the generation of other sub-products due to the electro-chemical dissociation of the electrolyte’s components, or to the addition of chemical additives, or due to specific physical conditions or lack of controls during the operation.

Jan 1, 2019

By C Doblin

Any value addition to the mineral sands in the Murray Basin (Australia) will generate waste that needs to be disposed of safely. For example, conversion of ilmenite and synthetic rutile to titania (TiO2) pigment would generate large amounts of environmentally undesirable elements. Processing of U+Th containing zircon sands to zirconia or to higher purity zircon would generate a low-level radioactive waste. In this study it is proposed that one way to circumvent the waste problem could be to contain such waste in magnesium-based (Sorel) cements. Containment of waste in magnesium cements is an attractive idea especially for the mineral sand processing companies that could operate in the Murray Basin in the future, because the required magnesium oxide and magnesium chloride may be made cheaply from the saline waters encountered during mining operations. The magnesium cement production process is also far less energy intensive than the Portland cement production process. The results of this study indicate that mixing a waste stream with a slurry of magnesium cement before being discharged to the disposal area would contain the waste in a æconcrete-likeÆ structure, resistant to dispersion by wind and moderate rain. However, some loss of strength and increased leaching of impurities, Mg and Cl could take place in wet climate areas. Ongoing research is being concentrated to develop a new process for making water-resistant magnesium cement.

Jan 1, 2002

It was Harold McMillan, Prime Minister of England 30 years ago, who used the phrase &quot;The Wind of Change&quot; to describe political events in Africa in his day. So well did this phrase capture the spirit of the time that it echoed around the world, and the echo has never stopped. Change is the constant factor in the society in which we live and everyone of us has had experience of the effect which it has had on our professional and personal lives.Change will not stop, it will continue at an increasing rate and the questions we must answer are how do we prepare ourselves to meet the challenge of future change and how do we take advantage of the opportunities which it will bring?It is these questions which I wish to discuss in this address.There is nothing new about change in the mineral industry, it has been happening for thousands of years and it will continue as long as civilisation exists on earth. One type of change is economic and we are all aware of the rises and falls which occur in the prices of metals and minerals (Figure 1). When these have happened in an orderly manner, and could be predicted and planned for, it has been possible to take advantage of the benefits and minimise ill-effects, but when they were sudden and precipitate, and could not be predicted, the consequences were serious. The extreme example, of course, was the oil price shock of the 1970s which had such disastrous effects on industry and society.Other types of change are social, cultural and political. They have all been important in recent years and will continue to be so in the future.But it is technological change which may well be the most important because its effects are profound and irreversible, and alter irrevocably the way in which we live. So in discussing the mineral industry in a changing world I will talk specifically about technological change.

Jan 1, 1989

By V. F. Petrov

Today, sodium cyanide is extensively used for extracting gold, however it is highly toxic to the environment if not managed properly. This paper discusses the key challenges presented to gold operations in efforts to come into alignment with the Russian environmental regulations and suggests solutions to overcome these challenges. It is a fact that the major environmental threat cyanide poses to water sources. Therefore, natural water sources should be well protected from the adverse effect of cyanides used in hydrometallurgical processes. For this, the following site procedures and facilities are practiced: in-site and external water recycling systems, reclaim water treatment if required and tailings ponds with water impermeable screens (tailings ponds with controlled leakage). Cost comparison analysis of cyanide destruction methods was carried out. It was revealed that the aldehyde treatment method developed by Irgiredmet JSC demonstrated the best economics. Cyanide emissions are treated by mass-manufactured packed and membrane devices which allow to keep cyanides at the acceptable limiting values established by environmental regulatory agencies.

Jan 1, 2014

By Ben E. Lusk

First of all let me say what a genuine pleasure it is to be here. Acapulco certainly is a beautiful change. I&apos;m going to spend sometime talking about change, because frankly I&apos;m astounded at the rate of change in our world today. One good example of this, reminds me that the first time I spoke before the AIME two years ago, we were at the Ramada Inn in Beckley, West Virginia. Today we&apos;re at the Princess Hotel in Acapulco, Mexico. Now that&apos;s what I call a change. Seriously though, I&apos;m sure you&apos;ve all heard it said that the most consistent thing about our society is its constant change. Five years ago, no one could have predicted the changes we experienced in the United States during the first half of the 1970&apos;s. In the past twenty-four months alone, we have seen two presidents, three vice-presidents and hundreds of administration and government personnel changes. We have stumbled from one social crisis to another, while suffering through rising inflation, major energy shortages and labor unrest that could plunge us into a full scale economic depression. In view of these constant and unpredictable changes around us, it&apos;s obvious that we must learn to deal with change and "roll with the punches" if we are to survive. A controversial book published recently, explores in detail the various aspects of change and its impact on man.

Jan 1, 1974

"IntroductionIn the 1970s, environmental concerns and associated liabilities were a new and unknown aspect of corporate risk. Today, social concerns and the associated conflicts that they can generate constitute a rapidly expanding aspect of risk. Although not a new phenomena — the Bougainville copper mine was forced into closure in 1988 — social risk has emerged as considerably more important, and increasingly visible, in the last few years. Social risk is now an aspect of all mining activities which needs to be calculated into project assessments, and to be managed throughout the life of a project. While social risk has a number of aspects at the corporate level, such as company image and shareholder relations, at the level of the individual project, its primary component is social acceptability, and the principal tool for managing it is the Social Licence to Operate.Social Risk in Latin AmericaThroughout Latin America there are newly modernized mineral codes and economic systems introduced over the last ten years which, together with new environmental legislation, look very much like regulations in developed countries. To the corporations, the existence of these instruments means that the risks from the environmental issues associated with the project are known; they are legislated, defined, quantifiable and hence manageable.It seems ironic that, just when comprehensive regulations for the environmental management of mining have been put in place throughout Latin America, there arise an increasing number of challenges to mining activities. For, in spite of the apparent guarantees provided by these new legislative reforms, communities in Latin America today are more frequently standing up and taking exception to the presence of mining companies, or the ways in which the companies are conducting themselves. The viability of projects becomes threatened because they are considered socially unacceptable, a phenomenon that we describe as social risk. These challenges are less about opposing mining activities than many people would think. Rather, they are based on an increasing desire on the part of the local population to have some measure of control over their own future, and to participate in the development process from the earliest stages."

Jan 1, 2000

By T. G. Carter

"Tremendous progress has been made in recent years towards developing computational tools that allow ready solution of most common rock engineering problems, with amongst the most advanced of the tools focusing on evaluating engineered openings within Synthetic Rock Masses. These new codes have the potential to allow much more realistic design, but they must not be used without careful calibration – prior to – during and – post completion of any modelling. This paper explores some of the pitfalls of inadequate data collection and suggests more emphasis be given to calibration. Guidelines for minimum levels of parameter data are suggested for improving application of basic to sophisticated modelling codes.INTRODUCTION & BACKGROUNDTremendous progress has been made in recent years towards developing computational tools that allow ready solution of most common rock engineering problems. The degree of sophistication now possible with some of the available codes allows one to tackle extremely complex problems that were not thought tractable even a decade ago. Indeed, generation of synthetic numerical rock masses, based on discrete fracture network representations that closely mimic actual rock mass conditions, such as are shown in Figure 1, is today relatively straightforward, and not as user-challenging as employing state-of-the-art codes of even a few decades ago. This is largely because major improvements in computer graphics and in availability of ready-made user-friendly input-output interfaces have paralleled development of these new codes, now in some cases outpacing actual new analytical/procedure developments. This is something of a reversal from the first few decades of DOS-based rock engineering computational experience, when only rudimentary graphics were available and user-friendly input-output interfaces were virtually non-existent."

Jan 1, 2015