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By Gerard Matthes

WITHIN the last three years, aerial mapping has made wonderful progress. Its three sources of development in North America may be enumerated as follows: (1) The work of the U. S. Army Air. Service and Corps of Engineers at the McCook Experimental Field, Dayton, Ohio. This is generally regarded as the backbone of this class of endeavor in the United States. (2) In Canada, a great deal has been accomplished in a practical way by methods that have not even been tried out in the United States. Under the leadership of the late Doctor Deville, the Dominion Land Surveyors have turned out reconnaissance maps of large areas at very, small cost. (3) Private capital has contributed a great deal toward development of aerial mapping in a practical way in the United States. Prominent in this regard stands the Fairchild Aerial Surveys, Inc. which has spent large sums in research and development work, especially in the construction of aerial cameras. Its camera is, at present, the official camera of the U. S. Army and Navy Air Services, also, of the Canadian and Brazilian governments. Aerial photographic surveying is a flexible process and adapted to a variety of uses. To date, it has proved. of direct practical value for engineering projects such as reservoir and power transmission surveys, railroad location, drainage, harbor front studies; also, for many commercial purposes, tax assessment, city planning, forest surveys, and lawsuits. In a few instances, aerial photographs have been used successfully by geologists as base maps on which to record field observations, thereby dispensing with pacing and compass surveys. There is reason to believe that, eventually, the aerial map will find wide application in the work of geologists. The reason for advancing this opinion is that aerial maps have, in other fields, proved more complete as regards detail than maps made by standard processes of surveying and drafting, and often are more accurate than the latter. At the present time, five distinct uses are being made of aerial photographs: There is the "oblique" photograph taken at an angle with the horizon; it is used extensively for illustrations in newspapers, magazines, and advertisements. Also, for reconnaissance purposes, it has been found of great practical value. For illustrating reports of engineers and geologists, it offers many obvious advantages. In the Canadian Surveys, maps have been compiled from oblique photographs.

Jan 3, 1925

By Gerard Matthes

ONLY in recent years has any practical headway been made in the application of aerial photography to geological problems, and up to the present time its principal value to the geologist and mining engineer has been in "areal geology;" i. e., the study of formations as revealed at the surface. The object of this paper is to set forth briefly the principal advantages that may be derived from aerial photographic data in geological work and to serve in a measure as a guide to those who may be con-templating its use. Geophysical prospecting has for object the locating of mineral under the surface. Inasmuch as the geologist's chief complaint in life is a dual one-inability to see under the surface and inability to visualize comprehensively what he does see on top of the ground-geophysical prospecting coupled with aerial photography should do much to lessen his burdens. To what extent aerial photography can be made a useful adjunct to geophysical prospecting remains to be proved, but the inference drawn here is that it holds many alluring possibilities. To avoid disappointments, it should be stated at the outset that to the :geologist or mining engineer an aerial photograph or mosaic is only a tool, the effecient use of which he must set out to master. Upon his skill and ingenuity in applying it to particular problems will depend largely the value of the results that he will obtain. Under the most favorable conditions an aerial mosaic or even a few loose photographs, because of the exceptionally comprehensive oversight which they afford of field data, such as dips and strike observations at isolated outcrops, local indications of faulting, mineral and fossil finds, greatly facilitate study and correlation, save much tedious foot work, and may repay their cost many times. Even so, types of country may be found where the most, skillful use of the best of pictures will produce results so meager as to render the cost of aerial photography entirely unwarranted.

Jan 1, 1928

By Leon Eliel

TEN years ago .a broad knowledge of aerial mapping, coupled with a smattering of geology, qualified one to speak on the subject of the appli-cation of aerial mapping to geology. Today, with aerial maps a common tool in the hands of expert geologists on every continent throughout the world, it would be nothing short of presumptuous for the author of this paper, who is not a geologist, to give any geological statements on his own authority. Relatively, today we are only purveyors of general geological gossip, with a definite case here and there by way of illustration. But we can present a story of the really marvellous strides that have been made in the evolution of aerial mapping, built around a skeleton of geological tidbits, from which some useful conclusions may be drawn. The average geologist goes about reading his aerial maps much as one would approach the problem of deciphering a cryptogram. To begin with, typical key expressions appear in recurring sequences and under certain conditions. If once the meaning of these. isolated bits of infor-mation can be ascertained, the message begins to take meaning.. In a similar fashion, the geologist works out his key from aerial maps of territory with which he has some familiarity. He learns that a certain type of thin, white line may mean a vein of quartz. He sees that a certain change in the photographic tone of vegetation on the ground reflects two kinds of soils on opposite sides of a contact. He sees that a certain type of alignment of topographical features often means a fault. He learns that by the erosion pattern he can frequently distinguish soft formations from harder ones. And so, bit by bit, he ties together the information of the picture with his experience on the ground until he develops a reasonably creditable capacity of interpretation. Through the complete gamut of surface conditions, ranging all the way from flat, arid, exposed desert terrain to dense jungle, or rugged mountains, the evidence from which the geologist must make his inter-pretation varies with bewildering profusion. The quality of photographs which are obtainable may range from perfect pictures in the desert to almost useless smudges in the steaming jungles. One thing he has learned with certainty-the airplane carrying its mapping camera is a superb reconnaissance tool, only awaiting his ingenuity in correlating the pictures with the ground to simplify most exploratory problems.

Jan 1, 1936

By Leon Eliel

TEN years ago a broad knowledge of aerial mapping, coupled with a smattering of geology, qualified one to speak on the subject of the appli-cation of aerial mapping to geology. Today, with aerial maps a common tool in the hands of expert geologists on every continent throughout the world, it would be nothing short of presumptuous for the author of this paper, who is not a geologist, to give any geological statements on his own authority. Relatively, today we are only purveyors of general geological gossip, with a definite case here and there by way of illustration. But we can present a story of the really marvellous strides that have been made in the evolution of aerial mapping, built around a skeleton of geological tidbits, from which some useful conclusions may be drawn. The average geologist goes about reading his aerial maps much as one would approach the problem of deciphering a cryptogram. To begin with, typical key expressions appear in recurring sequences and under certain conditions. If once the meaning of these isolated bits of infor-mation can be ascertained, the message begins to take meaning. In a similar fashion, the geologist works out his key from aerial maps of territory with which he has some familiarity. He learns that a certain type of thin, white line may mean a vein of quartz. He sees that a certain change in the photographic tone of vegetation on the ground reflects two kinds of soils on opposite sides of, a contact. He sees that a certain type of alignment of topographical features often means a fault. He learns that by the erosion pattern .he can frequently distinguish soft formations from harder ones. And so, bit by bit, he ties together the information of the picture with his experience on the ground until he develops a reasonably creditable capacity of interpretation. Through the complete gamut of surface conditions, ranging all the way from flat, arid, exposed desert terrain to dense jungle, or rugged mountains, the evidence from which the geologist must make his inter-pretation varies with bewildering profusion. The quality of photographs which are obtainable may range from perfect pictures in the desert to almost useless smudges in the steaming jungles. One thing he has learned with certainty-the airplane carrying its mapping camera is a superb reconnaissance tool, only awaiting his ingenuity in correlating the pictures with the ground to simplify most exploratory problems.

Jan 1, 1936

By A. R. Turner

AERIAL survey methods have made enormous technical advances and gained new recognition since World War II. Before enlarging on this statement and reviewing some of the uses of aerial survey in industrial development it is important to de-fine what is meant by "aerial survey". The subject will be discussed in the broadest sense and references will be made to the four sections that compose the overall field of surveying operations from the air. These are: 1. Aerial photography and photo-graphic mapping. 2. The use of airborne electronic instruments for geodetic distance measurement and the determination of ground elevations. 3. Airborne geophysical surveying. 4. The extraction of qualitative and quantitative information from aerial photographs through the processes of "reading", analysis and interpretation. Many sciences and techniques are combined in aerial survey operations. The tools of the business include aircraft, finely engineered cameras, elaborate film processing and printing equipment, ground survey instruments, precision stereo-plotting instruments, map -

Jan 1, 1961

By Maurice Lauzon

"Aerial surveys of the open pits have been conducted regularly at Lake Asbestos of Quebec, Ltd. -a subsidiary of American Smelting and Re-fining Company -since 1958. Ground controls are supplied by Lake Asbestos, and a topographic map of the pits at a scale of 1 in. to 50 ft., with 2-foot contour intervals, is obtained by aerial photography. The information from the topographic map is then transferred by the Lake Asbestos engineering staff to sections from which the volumes removed are calculated. Considering the size and complexity of the operation, this system has proved to be the cheapest, fastest and most accurate way of determining the quantities of rock and overburden removed. More than 11,000,000 tons of ore and waste are mined each year in three different pits. Further-more, the nature, shape and extent of the orebodies make it necessary to mine on many (up to eight) benches of a pit during a single year. In addition, there are sections of the pits where it is impossible or un-safe to survey the crest of some benches by standard ground methods. For these reasons, the tonnages obtained by truck count are checked and adjusted by aerial survey. These surveys are now taking place every six months. With this system, it is possible for a two-man surveying crew to look after all field work in the mine area."

Jan 1, 1967

By Dale L. Pitt

Introduction In opening up a new country, one of the most vital problems is that of transportation Without roads, railways, or water routes, development is very slow because these are the arteries through which the life-blood of the country flows. British Columbia is unusually fortunate in having along its western coast, for some 600 miles, a stretch of inside water unequalled, for comfortable and safe navigation, by any other similar stretch of ocean in the world. This solves in a general way the major north and south transportation problem for the coast section, and offers comparatively cheap rates for the shipping of all commodities. The principal cities and centres of distribution will naturally grow up on the coast. These cities, however, must have methods of communication with the hinterland, and it is the necessity of supplying these, as feeders to the principal ports, which presents problems of considerable magnitude.

Jan 1, 1930

By Storey AG

Following initial plant scale work on the development and performance of 'spray' oil lances, a full scale room temperature model of the blowpipe-tuyere region of a blast furnace was built to study the basic aerodynamic features of auxiliary fuel injection procedures. Mobilwax 2305 was used as a substitute for Bunker C oil fuel in view of its similar physical properties and the fact that the atomised droplets could be frozen in flight and size, distribution analyses made for various operating procedures. It was shown that secondary atomisation processes far outweighed the importance of any primary atomisation procedures in determining mean Sauter Diameters particularly at high windrates typical of current blast furnace technology. It was also found that good spray dispersions across the blow pipe could only be obtaind for liquid fuels and that the lateral rate of spray dispersion was substantially enhanced by primary atomisation procedures. Mean particle diameters of sprays were found to be predictable on the basis of elementary stability theory and fell within the size range necessary for good combustion at all liquid fuel rates studied. The possible effects of high oil injection rates on flooding phenomena in the furnace bosh were considered. Comparisons show that high oil rates can lead to significant increases in the hanging factor (e.g. 'V 10% at 135 kg oil/thm) owing to increased gas flow rates/thm resulting from the presence of hydrogen.

Jan 1, 1975

By Henryk Bystron

The underground fire areas are formed as a result of failure of an active fire extinguishing in mines. Such areas bring about a fire hazard for the work safety and for the mining operations. For liquidation of fire areas it is necessary to create conditions under which a possibly small amount of air is flowing to the fire. To achieve this end, isolation methods are used which consist in erection of full stoppings of various types, sealing practically the fire areas. These methods usually fail in oases when the coal seam is thick and the fire area is situated between the intake shaft and the outtake shaft in which a high-pressure fan is in operation. In such oases ventilation methods based on the balance of aerodynamic potentials in fire areas are to be used. For a very long time the isolation and ventilation methods have been developed in the world mining, No sooner than since 1980 the aerodynamic potential has been used in ventilation methods [1,2,6]. So far, the aerodynamic potential was called in different ways and was determined by different formulae which gave its numerical values more or less approximative. Nevertheless, even in situations featuring by a lack of sufficient theoretical bases of the aerodynamic potential the ventilation methods brought considerable profits in the field of safety in mines and of economics in mine ventilation [1-6,9,10]. The increase in the depth of underground mines and their equipment with expensive machines (apparatus) brought about that the Central Mining Institute at Katowice undertook research works which are crowned by the theory of the aerodynamic potential in mine ventilation networks [7]. The use of this theory in the mentioned ventilation methods will increase their effectiveness. Since the theory will be published in the III rd quarter of this year, we cite in the present paper the formulae and relations associated with this theory which are indispensable to present the balance of aerodynamic potentials in the fire areas in their control by ventilation methods.

Jan 1, 1980

By Ezz El Din Abdel Hakim Khalaf, Khalid S. Essa, Marc Munschy, Mohamed A. S. Youssef

This study focused on joint interpretation of the aeromagnetic and radiometric data to allocate and describe the structural elements and mineralization zones such as uranium, gold, and sulfide in the Gebel Umm Tineidba and its surroundings, Eastern Desert, Egypt. The study region is covered by exposures of Precambrian rocks such as gneisses, migmatites, ophiolitic mélange, metavolcanics, younger granites, and Quaternary sedimentary covers. The application of the total intensity magnetic and reduced-to-pole maps, power spectrum, analytic signal, tilt-angle, and local wavenumber maps helps in recognizing magnetic sources distribution, lineament features, and mineral zones delineation. The obtained results indicate that the depths of the deeper NE–SW, NNE–SSW, and N–S trending structures extend from 400 to 1750 m and shallower ones range from 100 to 400 m. Finally, the main trends of these structures affect the probable mineralization zones.

Sep 22, 2022

By C Munro, S Emery, M Flynn, K Tan

"AEROPHINE® 3418A Promoter is a well-known and widely used collector and is an industry standard for its excellent selectivity and efficacy in the processing of complex polymetallic sulfide ores, particularly those containing silver. Until now, however, it has not found widespread use in primary nickel flotation.In an effort to increase nickel recovery without compromising selectivity over iron sulfides, Western Areas Forrestania Nickel operation trialled the use of AEROPHINE® 3418A as a secondary collector at low dosage. A series of ON/OFF trials were conducted, with the finding that a very low dose of AEROPHINE® 3418A increased nickel recovery by 0.6 per cent compared to using xanthate alone.This paper provides a brief operational history and overview of the Forrestania operations, a description of the trial and an analysis of the results.Citation:Emery, S, Flynn, M, Tan, K and Munro, C, 2016. Aerophine® 3418A Promoter as a Secondary Collector to Boost Nickel Recovery at Forrestania Nickel Operations, in Proceedings 13th AusIMM Mill Operators’ Conference 2016, pp 145–148 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Oct 10, 2016

By F. Bruey, T. Bruce, D. R. Nagaraj, W. Thomas, P. Riccio, E. Guitard

"AEROPHINE® 3418A Promoter is a flotation collector that has been an industry standard in the Canadian mineral processing industry since its first commercial use at the Kidd Creek concentrator in 1980. Its wide range of applications in sulphide mineral flotation has made it successful, specifically in the processing of complex sulphide ores which contain copper, lead, zinc, and silver or any combination of these elements for selective separation.AEROPHINE® 3418A Promoter is a unique, phosphine-based collector originally developed for the flotation of copper sulphide minerals and activated zinc minerals. It is now recognized for its selectivity for complex, polymetallic sulphide ores and porphyry copper ores. In addition, AEROPHINE® 3418A Promoter is highly selective for copper, lead, activated zinc, nickel and precious metals. AEROPHINE® 3418A Promoter exhibits strength yet, selectivity against iron sulphides (pyrite, pyrrhotite, marcasite, and arsenopyrite), non-activated sphalerite, and many minerals which contain penalty elements.This paper outlines a brief history of the product’s development, its historical use in Canada and several potential innovative mineral processing applications with the use of the chemistry. Three Canadian case studies will be presented on various ore types including: a Cu-Au ore, a Cu-Zn ore, and Cu-Pb-Zn ore. A plant production update will also be given on the future supply of AEROPHINE® 3418A Promoter.INTRODUCTIONCytec Industries Inc. operates a phosphine derivatives plant in Niagara Falls, Ontario, that manufactures various products for their speciality chemicals division. The products from this site are based on phosphine (PH3) chemistry and are used in a variety of markets including electronics, agriculture, LED lighting, water treatment, metal extraction, and mineral processing. One of the major products is the phosphine-based sulphide mineral collector, AEROPHINE® 3418A Promoter.AEROPHINE® 3418A Promoter (Figure 1) was originally developed for the flotation of copper and activated zinc minerals (Thomas, 2010).."

Jan 1, 2015

By A. W. Jolliffe

AEROPROSPECTING may be defined as the application of the air view to the search for mineral deposits. The term is suggested as a preferable alternative to either aerial prospecting (which may be confused with areal prospecting) or air prospecting. The air view may be obtained by visual observation from an aircraft or by examination of air photographs; each has its particular advantages and disadvantages. Aeroprospecting should be regarded only as an aid to, and not as a substitute for, accepted prospecting methods ( l ). The Precambrian region north of Great Slave lake consists of two well defined physiographic units, a feature first noted by J. T. Wilson (2). The boundary between these lies close to the north shore of the east arm of the lake and extends northwesterly near Spencer, Beniah, Carp, and Ghost lakes (Figure 1). South and west of this line, exposed bed-rock makes up the greater part of the land area; eskers are very rare, and overburden is largely limited to rock-walled valleys and depressions. North and east of the line, outcrops are rare or absent, eskers are abundant, and most of the surface consists of drumlin-like drift hills, elongated parallel to the direction of ice movement (Figure 2). Where this boundary passes through the area shown in Figure 1, it lies near the 1,200-foot contour and may mark the maximum extent of the lake or sea arm present in this vicinity toward the end of the Pleistocene period. For convenience, the first area may be called the 'bed-rock belt' and the other the 'drift belt'.

Jan 1, 1945

By Mary Fu, Helen Leung, Colin R. Phillips

In uranium mines, the median size of the aerosol has been found to be about 0.1 micron or less. Such small aerosols are readily deposited or "plated-out" on dosimeter interior surfaces resulting in the recording of a low dose. The "plate-out" properties of the CEA alpha dosimeter head are described with respect to aerosol properties in controlled experiments in the laboratory. A simple model is derived to estimate the amount of "plate-out" in the CEA head.

Jan 1, 1981

By R. Mumbi, M. Peart, E. Arinaitwe, B. Mbao, J. Zulu

Since 1925, xanthates have been widely used in sulfide flotation due to their low cost, ease of manufacture, and ability to float most value species. However, the industry's increasing need for safer and more selective alternatives, driven by low head grades, poor-quality, difficult-to-process ore with complex mineralogy, and stricter environmental regulations, has led to the development of Solvay's AERO® XR series of collectors. These custom-formulated products are based on greener chemistries and offer metallurgical benefits that are similar to or better than those of xanthates, without the safety concerns. Developed through Solvay's Flotation Matrix (FM) 100 approach, the XR series collectors are suitable for a wide range of applications, including the processing of Cu, Zn, and Cu-Ni, as well as the flotation of precious metals. This paper will highlight the differences between xanthates and XR series collectors, and present case studies of their successful commercial application at various global operations.

Jan 1, 2023

By F. Heivilin

Little did I know, in 1977, that when the A. P. Green Refractories Raw Material Manager showed me 5-6 burlap bags with samples of calcined high alumina bauxite in their testing lab that this was the start of China moving to be the number one user and producer of calcined refractory bauxite. According to Ted Dickson in his August 2008 Industrial Minerals article China produced about 4 million tons of calcined bauxite in 2007 using 2 million tons themselves. They imposed an export limitation of 970,000 tons in 2007 and 940,000 tons in 2008. A 10% growth will take up the difference between exports and production in 4 years. Two of these years are gone. It will take only 4 more years to eliminate the export quota in home use. Then they will be importing unless they increase production. Guyana was exporting over a half million tons in 1975 and sold less than 70,000 tons in 2002. Basai Metals Group bought Guyana?s deposits and is rose to 250,000 tons in 2007 and expects to produce 280,000 tons in 2008. PRICES According to the USGS Prices dropped from $172/per ton for Guyana calcines in 1980 just after the start of Chinese production to $122 in 1985. Guyana prices averaged around $120/ton from 1985 to 2005. China?s price dropped as low as $45/ton in 1995 undercutting Guyana and making it virtually impossible for anyone to get into the market. The price suddenly escalated to $550/ton FOB China in the summer of 2008 when China actually cut its exports in half. The price dropped in the fall as orders dropped. This is a four to five fold price increase. Is this a shortage of bauxite or a monopoly? Australia dropped out of the market in 2008 and Surinam, controlled by Alcoa, is not participating right now. Will these two come back in to make up the difference? Will the price hold up so they can make a profit? [ ] The low prices have undoubtedly affected the prices of the 60 and 79% alumina bauxite which can hold down the quantity of 80% plus calcined refractory needed in the world market. China is starting to upgrade lower quality bauxite up to 90% alumina. With high prices kaolin alteration to high alumina comes into play. The calcined bauxite is also used for proponents, Brown fused alumina, and abrasive grades which compete with Refractories. These and the tightness of supplies needed for metallurgical will hold prices up. TONNAGE China is the number one supplier and consumer of high alumina calcined bauxite in the world. Basai Metals Group Guyana (BMGG) is owned and controlled by Basai Minerals Group of China. This appears to be the second largest supplier. Australia has dropped production and Brazil is just starting to expand. It appears China is going to replace some of exports caused by the Export License 940,000 ton maximum in 2008 by raising Guyana?s (BMGG) production of calcined refractory grade bauxite. Companies exceeded restriction in 2007. Fines have been imposed for 2008. In August 2008 they appear on line to meet the 2008 quota. After August prices have dropped off as orders dropped due to the recession. Guyana was the largest producer in 1975 with 769,000 tons which decreased to less than 79,000 tons in 2002. The U. S. is a small part of the world production. I have used the United States charts to represent world imports because I have little data on what other countries import and pay FOB for their bauxite. China started exporting calcined 80% plus refractory bauxite to the United States in 1979 with 24,000 tons. By 1985 they were the number one importer with 169,000 tons. Guyana who had been number one in shipments to the United States gradually decreased to 36,000 tons in 2006. Guyana has been purchased by China BMGG and will increase there production to over 200,000 tons in 2009. Australia shut down production in 2008 and Surinam has elected to not send any Calcined bauxite to the United States. Imports to the United States from 1978 to present are as follows: [ ] Refractories are important because they affect 96% of the GNP. During the cold war we had stockpiles of 80% refractory grade bauxite

Jan 1, 2009

The Oregon School of Mines Society held its regular monthly meeting on the evening of October 23. This meeting was an informal reunion at which members gave accounts of personal experiences during the last three months. Many members of both junior and senior classes answered their country's call to arms and so did not return to college. The senior class is particularly well represented in the Army, as two men hold lieutenant's commissions and a third is already in France with a hospital unit. The junior class has also contributed men to various branches of the service. Plans for the regular meetings include discussions by members and lectures by outside authorities oil mining and allied topics. These meetings are open to the lower classes and all others interested. The Oregon School of Mines Society, composed of members of the junior and senior classes, has, joined with the sophomore and freshman relining students in purchasing a Liberty Bond under the name of the Miners' Club of 0. A. C. H. W. THOMS, President.

Jan 12, 1917

The Board of Directors, at its meeting on March 22, 1918, extended an invitation to the American .Institute of Metals to become the Institute of Metals Division of-the American Institute of Mining Engineers in accordance with the terms of By-Law VII. This invitation was presented to the membership of the American Institute of Metals for letter ballot, and, at the meeting of the Board of Directors of the American Institute of Mining Engineers on April 26 191 ,it-was reported that the replies had been in favor of accepting the invitation. The American Institute of Metals therefore becomes a division of this Institute and the members thereof are entitled-to all privileges of regular

Jan 6, 1918

By J. J. Benitez

MIBC (methyl-isobuthyl carbinol) was previously shown to enhance significantly sylvite flotation when used at the stage of preparation of amine dispersions. In this paper Atomic Force Microscopy (AFM) is used to study the effect of MIBC on deposition of octadecylamine (ODA) on the surface of mica. The AFM images indicate that amino terminated, and therefore hydrophilic, deposits of ODA are observed on the mica surface in the ODA dispersions free of MIBC. In the presence of MIBC a methyl terminated (hydrophobic) monolayer is obtained on the mica surface. The transition between the monolayer and bilayer phases is due to the presence of MIBC. Experiments carried out in distilled water reproduced the results obtained from the brine. Working in pure water instead of brine simplifies the preparation conditions and the analysis by AFM.

Jan 1, 2006

By C K. Bell, L. S. Collett

An AFMAG survey was flown in 1968 over the Upper Nelson River area, Manitoba. The flight direction was northwest-southeast and flight spacing was 2 miles. In the Cross Lake Subprovince, AFMAG showed that an isolated peridotite outcrop was part of a dike that extended over 80 miles. Diabase dikes are not always marked by an anomaly, but isolated cross-overs, when used in conjunction with geological and magnetic data, permit their extrapolation. Anomalies coincide with areas of sulphide mineralization. In the Flin Fion Subprovince, known and unknown northeast-trending faults are detected. The Berry Creek fault was extended south through Tramping lake, then under the Paleozoic cover. Conductors were detected at, or near, the axes of major synclines within Amisk and Snow Group sediments. Granitic terranes have low conductivity and, because they are characterized by smooth AFMAG profiles, they can be delimited. AF.MAG is being recognized as a geophysical method that can aid geological mapping and interpretation. Its most important contribution to the geologist will be in regions where out-crops are sparse.

Jan 1, 1971