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By George Langford

Introduction The fiftieth anniversary is, for an individual or a society, an appropriate time for a review of the past so that events and experiences may be viewed m perspective, and thereby serve as a useful guide to the future. In this review of mining geology it is proposed to set forth the situation as it was when the Institute was founded, and then trace the developments during three appropriate periods-the first from 1898 to 1918 the second from 1919 to 1939 and the third from 1939 to 1948. Mining activities were widespread in Canada in 1898 and some of the operations were considered large for their day. The total value of the metals produced in that year was $21,705,854, and in the case of five metals the output had a value in excess of one million dollars. In order of importance these were gold, silver, copper, nickel, and lead. The important producing areas were ova Scotia, Quebec, Ontario British Columbia, and Yukon. This diversification of the mining areas and the metals produced created an interest in mining throughout Canada, and was an important factor in making Canadians conscious of their mining industry. In the year 1898 geology was a recognized science. The principles of physical geology were well known, but the same cannot be said of economic geology and structural geology. Ore deposits and their occurrence had been studied chiefly in Europe. A great many important observations had been made but the theories linking these facts together were still m a formative stage. The same condition was true of structural geology. These two branches of geological science which are so important in what is now called 'mining geology', had not progressed far enough to be of practical assistance mining operations. For this reason, geologists were regarded as dreamers in ivory towers-a concept chat still lingers in the minds of those who have not kept abreast of the growth of the science.

Jan 1, 1948

By Oscar H. Hershey

COMPLAINT has been made that in the literature of economic geology the work of the "company or practical" mining geologists does not get enough attention. I propose to attempt to overcome this com¬plaint in reference to one important lead-mining district, that of the Coeur d'Alene in northern Idaho. Furthermore, I will assume that the reader is not so much interested in the geology of the district as in the methods of application used and incidents that have arisen in the work. All the important discoveries of ore in the Coeur d'Alene were made without benefit of geology. Certainly I would not claim the reputed discoverer of the Bunker Hill mine as a fellow geologist. It appears also that the mines were operated quite successfully for many years without geological specialists, though doubtless certain properties were visited at long intervals by such men as Waldemar Lindgren. It was known that the ores occur in quartzite, graywackes and slates as stated by J. R. Finlay in 1903. (TRANS., VOL. 33.) He described the ore as occurring in typical fissure veins that occupy fault-planes of indeterminate displacement. The Bunker Hill lode was based on a definite fissure with the mineralization all on the hanging-wall side, extending as far as 300 ft. from the fissure.

Jan 1, 1933

By Charles H. Behre

KEYNOTE of the mining geology sessions was the preparation for an extensive war with all that this implies as to the need for strategic minerals, both metallic and nonmetallic. Nevertheless the sessions also included many papers of less urgent, more theoretical interest. The stress of wartime production had the effect of giving an unusually full and rich program, the longest in recent years, with sessions continuing virtually throughout the meeting. Some papers dealt with geophysical prospecting as applied to mining geology; others were concerned with the grand strategy of mineral reserves and thus involved the industrial minerals; such "borderline" subjects were presented before sessions held jointly with the Geophysics Committee or the Industrial Minerals Division.

Jan 1, 1942

By E. Y. Dougherty

Introduction As practised during the last two years at the Vipond Consolidated gold mine, mining geology has meant the application of geology to the problem of finding, developing, and mining ore. This article reviews the results attained in Vipond mining geology as thus defined. Most effort was directed toward clarifying and interpreting the tangible physical causes of vein and ore localizations, and in the following pages these questions are dealt with in considerable detail. Discernment of the influence of rock folding and deformation on the localization of veins, and of the influence of certain structures and rocks in or near carbonaceous zones on the localization of ore-bodies, have been the main practical results of the studies. Consideration of some of the geological features of the Porcupine area, and of the geology and mining experience of the principal producing mines, has helped toward a perspective of Vipond's ore-finding problems. These features are first discussed. The background and procedure for Vipond mining geology, and the major results of the geological mapping, are then summarized. Then follows a résumé of tangible factors that influenced vein, ore-body, and gold localizations; and, next, explanations of the facts ascertained. Because they were found of little utility, many fascinating problems, such as the origin and mode of emplacement of the veins and lodes(l), the ultimate source of the ore, and the physico-chemical and mechanical agencies affecting vein and ore formation, are treated cursorily or are neglected in these notes.

Jan 1, 1934

THE papers by G. F. Loughlin and I. A. Ettlinger discussed the distribution of formations and ore-bodies in two of the main mining districts of the Southwest. The convergence of the deeper orebodies at Cripple Creek points to their common hypogene ori-gin, as do the occurrences of the copper ores of, central Arizona. E. L. Bruce described the areas in southwestern On-tario around Red Lake and Woman Lake, another prom-ising gold district. Of special interest was a series of lantern slides showing the use of power-driven boats and of hydroplanes as means of transportation. Within a few years, no doubt; such devices will revolutionize the mining industry and reconnaissance mapping in these relatively inaccessible areas. Much interest was evinced in the paper by J. W. Finch on "Sedimentary Metalliferous Deposits of the Red Beds." It was written as a caution to people at-tempting to mine these deposits. The discussion of the chemical equations presented in the paper brought out the fact that a large amount of study of such ores is necessary before we shall be able to write equations to explain their formation. Especially pertinent were the discussions by David White as to the relation of decay-ing plant tissue to metalliferous deposits and the color of sediments; also the point brought out by T. S. Lover-ing that chemical compounds produced by bacteria may greatly affect the deposition and reorganization of sedi-mentary metalliferous deposits.

Jan 3, 1928

By Willard C. Lacy

Survival of the mining industry as a viable economic entity in the United States is being seriously threatened by declining grades of ore reserves, rising operational and capital costs, and increased governmental taxes, restrictions, and subsidizing of third world competition. Discovery of major high-grade deposits is becoming increasingly unlikely. International competitiveness of the U.S. deposits will depend upon 'Yankee Ingenuity, ' innovations in mining methods, metallurgical treatment, and financial arrangements, and a viable national strategy. This will require not only effective management for control of operations, but management that encourages breakthroughs in technology, financing, labor relations, and in public and governmental understanding. The mine geologist and the exploration geologist both have important roles to play in all aspects of this fight for survival of the industry.

Jan 1, 1985

By R. A. Metz, Willard C. Lacy

Survival of the mining industry as a viable economic entity in the United States is being seriously threatened by declining grades of ore reserves, rising operational and capital costs, and increased governmental taxes, restrictions, and subsidizing of third world competition. Discovery of major high-grade deposits is becoming increasingly unlikely. International competitiveness of the U.S. deposits will depend upon 'Yankee Ingenuity,' innovations in mining methods, metallurgical treatment, and financial arrangements, and a viable national strategy. This will require not only effective management for control of operations, but management that encourages breakthroughs in technology, financing, labor relations, and in public and governmental understanding. The mine geologist and the exploration geologist both have important roles to play in all aspects of this fight for survival of the industry.

Jan 1, 1992

By Willard C. Lacy

Survival of the mining industry as a viable economic entity in the United States is being seriously threatened by declining grades of ore reserves, rising operational and capital costs, and increased governmental taxes, restrictions, and subsidizing of third world competition. Discovery of major high-grade deposits is becoming increasingly unlikely. International competitiveness of the U.S. deposits will depend upon 'Yankee Ingenuity', innovations in mining methods, metallurgical treatment, and financial arrangements, and a viable national strategy. This will require not only effective management for control of operations, but management that encourages breakthroughs in technology, financing, labor relations, and in public and governmental understanding. The mine geologist and the exploration geologist both have important roles to play in all aspects of this fight for survival of the industry.

Jan 1, 1984

By AIME AIME

APOCRYPHAL, no doubt, but widely entertained is the proposition that top-flight mining geologists never agree with each other on anything. Being rugged individualists, they frequently seem intolerant of opinions that conflict with their own. However, one may suspect that controversy is often more apparent than real. For example, at last summer's meeting of the American Mining Congress, Ira B. Joralemon and Reno H. Sales, discussing "Mining Geology, Today and Tomorrow," seemed to be in serious disagreement over various phases of the subject; but much of this arises from the different angles of approach of the two distinguished and successful ore finders.

Jan 1, 1941

By Szwedzicki T

In recent years substantial advances have been made in the field of geomechanics. Staff at the Western Australian School of Mines (WASM) are keen to see that such advances continue and that the mining industry in Australia can take full advantage of such developments in a timely manner. WASM views mining geomechanics in its broadest sense, as being concerned with the characterisation of the physical properties and the behaviour of earth materials (soil, rock and water) and openings as mining proceeds. Aspects such as, soil and rock improvement techniques for difficult site conditions and the rock breaking processes, are also considered to be an integral part of mining geomechanics. This paper indicates the inter-relationships between the various areas within the field of geomechanics and the strong reliance of all of these areas on site specific engineering geology.

Jan 1, 1992

Data for 1962 world-wide, non-communist bloc geophysical activity, including geochemistry, are now available through the Society of Exploration Geophysicists. This information was made available to the AIME Geophysics Unit Committee through the courtesy of Charles L. Elliot, Mining Coordinator for the SEG. The data were compiled from 245 responses to 496 questionnaires mailed (49%). The data for the U.S. are a realistic representation of actual activity, followed by Asia, Canada, Europe, Australia, Africa and Latin America in order of decreasing reliability.

Jan 9, 1963

To help meet the challenge of mine finding at the start of the 21st century, the exploration geophysicist will have at his command a powerful range of tools, some new, some improved, and some which already exist today but are as yet little used. Remote sensing, using satellite and aircraft-based multi-spectral scanners, will provide the means for routinely mapping the surface distribution of certain carbonate rocks, clay and ferrous alteration minerals, based on the analysis of solar reflectance spectra. Time and emission-spectral resolved laser-induced fluorescence will likewise map the distribution of certain ore and pathfinder minerals, as well as certain skarn zones, all potentially related to ore deposits. The GPS (Global Positioning System), based on 18 orbitting satellites, will provide a universal, three dimensional, all weather navigation system which will completely supplant all existing aerial navigation systems, and greatly facilitate aerial surveying and automated processing and presentation of the data. Aeromagnetic gradiometer measurements will provide higher geometric resolution which will yield better definition of individual geological units. Multi-method ground geophysical surveys will be greatly expedited through the use of portable microcomputer-based, multi-sensor instruments. These instruments will interface with other intelligent devices for automated processing, presentation and interpretation of the ground field data. Borehole geophysics will come into more general use, both for at-hole measurements, especially using active nuclear techniques for grade determination, and for remote detection using a variety of electrical, magnetic, seismic and other methods.

Jan 1, 1986

By Hans Lundberg

IN last year's report on the progress of geophysics, the airborne magnetometer was the featured new development. At that time only a relatively small number of surveys had been made. During 1947, the airborne magnetometer was used in making many surveys and is again one of the high lights of the year in geophysics. This report is mainly concerned with geophysics as applied to the search for minerals exclusive of petroleum. In 194,5 and 1946, the use of the magnetic method reached a peak, partly because of an active period of prospecting brought on by an active mining market, particularly in Canada.

Jan 1, 1948

By Hans Lundberg

AFTER the war years, great activity has been shown in geophysical exploration for ore. The appreciation by mining and government geologists of geophysical techniques and results is largely responsible for the popularity of these methods. In Canada, plans are being made to study, by geophysical methods, the structure of a portion of the Pre-Cambrian shield in the hope that such studies will not only give a clearer picture of the geology, but will be of direct aid to the mining companies when selecting areas for detailed prospecting. Although geophysics thus has become more popular, some engineers are still reluctant to employ the methods to their full extent. Allotted funds are often rather low, so that the least expensive

Jan 1, 1947

By D. S. Parasnis

The early beginnings of mining geophysics in Sweden can be traced back to the reign of queen Kristina in the 17th century. The mine compass, consisting of a freely suspended magnetic needle in a casing, was in use certainly by 1640 and probably earlier for locating iron ore deposits. Whether the mine compass was a Swedish invention or not is an unsettled question since the possibility cannot be overlooked that the celebrated Nürnberg compass-makers of the 16th century may have constructed it for the first time(1). Be that as it may, the mine compass was very extensively employed in Sweden for more than two centuries and met with spectacular success in locating magnetic deposits under shallow overburden. Occasionally the diligent prospector would even be rewarded with a pyrrhotitebearing sulphide deposit, as witness many old sulphide-ore pits and some mines still in operation from the 17th and the 18th centuries. The mine compass measured only the orientation of the Earth's magnetic field and not its strength. Although it was improved in construction and sensitivity over the ages, no great strides were made in magnetic prospecting after the initial discovery of the use of the compass until Gauss, omnipresent in 19th century physics and mathematics, showed with the assistance of Weber how the strength of a magnetic field could be determined.

Jan 1, 1975

By Vincent A. Scovazzo

Benchmarking is a business management process that seeks improvement through the study and reapplication of practices conducted by industry leaders. This discussion presents objectives and organization of benchmarking applied to mining geomechanics. Similar procedures have been successfully applied to mining companies, laboratories, and research organizations involved in mining geomechanics throughout the world. Benchmarking is a structured process that allows an organization to learn from the "best" in the field. The objectives of benchmarking vary depending on the company's targeted areas for improvements. Typical goals include ground control cost reduction, enhanced safety, optimization of geotechnical staffing, development of state-of-the-art design procedures, or the adoption of the "best in the field" geotechnical data management. Once the objective of the study is established and the practices and procedures to be benchmarked are identified, a benchmarking team is formed from internal and outside specialists. Benchmarking in geomechanics is fundamentally different than in most other fields because of the effects of local geologic conditions and regulations, both of which must be understood by all on the benchmarking team, before a comparative analysis can be made.

Jan 1, 2000

By RUSSELL C. FLEMING

GILSONITE is a brilliant black, tarry-like bitumen, classed technically with glance pitch and graharnite as an asphaltite. As found it is brittle, breaking much like ice, and has a conchoidal fracture. Purest forms are used in the manufacture of paints, varnishes, electrical irisulatiorl, and inks for rotogravure; molded articles such as switch handles, telephone mouthpieces, and but- tons are made from the intermediate grades, and the poorer grades are used for the saturation of felt. According to the U. S. Bureau of Mines figures, production grew from about 4000 tons mined in 1904 to 55,000 tons in 1929. This asphaltic substance is found only in the Uintah basin in northeastern Utah, in veins over a wide area. Veins in the vicinity of Fort nuchesne were first discovered about 18G2, on what was then the Uintah Indian reservation, and the vein matter was originally called Uintaite because of that fact, In the early days, S. H. Gilson. of Salt Lake City, was so persistent and zealous in his efforts to develop the deposits and find a market that the name gilsonite was given to the material. Later, the wider and more renowned wins near Wayson and Dragon, in extreme eastern Utah, became the main supply.

Jan 1, 1932

By I. S. Parrish

Gold deposits in Hebei and Shanxi provinces in northeast China fall into three general classes: - Placer deposits - Mesothermal vein deposits - Disseminated and oxidized volcanogenic deposits Past production dating back thousands of years has all but exhausted the placers. The mesothermal vein deposits, incorrectly considered in the past as "greenstone" type, are small to moderate in both size and grade. Production from these granulite and amphibolite hosted veins, at present greater than from the newly discovered disseminated deposits, is expected to wane. Production from the disseminated deposits achieved only in the past few years is expected to equal or surpass that from the other classes of deposits. At least one "world-class" deposit is being developed.

Jan 1, 1989

By Allan P. Fawley

ONE hundred miles from Vancouver, at an elevation of 4,000 feet, is the Pioneer mine. It is situated on Cadwallader creek, a tributary of Bridge river, and is reached by travelling from Vancouver to Squamish by boat, a distance of thirty-two miles, from there by train to Bridge River (one hundred and seven miles), and finally by automobile across Mission mountain .(7,000 ft. elevation) to the mine (fifty-six miles): a total distance of one hundred and ninety-five miles. Prior to 1924, many Companies had examined the Pioneer, which had been developed by shaft to a depth of 200 feet, but, while values were good, the small size of the ore-shoot discouraged large investors. In July, of that year, opera-tions were re-commenced by the late David Sloan and, on sinking further, the ore-shoot was found to lengthen greatly as well as to ex-tend in depth, while remarkable gold values also were encountered. When, later, the price of gold rose from $20 to $35 per ounce, the mine was in an excellent position to take full advantage of the increase + and not only became an extremely profitable enterprise itself but its success greatly stimulated the search for and development of other 1-gold properties in British Columbia.

Jan 1, 1937

By P. I. Page

In mineral exploration the place that yields the first significant result is marked and two questions are posed immediately. Where should the next sample be drawn and how big should it be? At present the answers are arbitrary and ad hoc. They depend on personal experience and sentiment?that is hunch. The thought processes involved in reaching the decisions are unsatisfactory and unsatisfying for professionals. This paper proposes guidance on choosing sample spacing and sample size. The guidance is obtained from the grades of the samples. The grades also imply the extent of influence of each sample assay. Thus sampling and assay are integrated. The integration is achieved by changing the unit of value in which assays and grades are expressed and by exposing meanings and functions of grade beyond that of measuring rock value. The proposals are extended to guide comminution of particle size in sample size reduction and to deal with the problem of erratic high assays. Also, elucidation becomes possible of the computation of a reliable figure for average grade as a statistical weighted mean.

Jan 1, 2005