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TitleFirst vertical derivative of magnetic anomalies map, Canada / Carte des anomalies de la derivée première verticale du champ magnétique, Canada
LicencePlease note the adoption of the Open Government Licence - Canada supersedes any previous licences.
AuthorMiles, W F; Oneschuk, DORCID logo
SourceGeological Survey of Canada, Open File 7878, 2016, 1 sheet, Open Access logo Open Access
LinksGeophysical Data - Données géophysiques
PublisherNatural Resources Canada
Documentopen file
Lang.English; French
Maps1 map
Map Info.geophysical, magnetic anomalies, first derivative, 1:7,500,000
ProjectionLambert Conformal Conic Projection (NAD83)
Mediaon-line; digital
RelatedThis publication supercedes First vertical derivative of magnetic anomalies map, Canada
RelatedThis publication is related to Magnetic anomaly map, Canada
File formatpdf
ProvinceBritish Columbia; Alberta; Saskatchewan; Manitoba; Ontario; Quebec; New Brunswick; Nova Scotia; Prince Edward Island; Newfoundland and Labrador; Northwest Territories; Yukon; Nunavut; Canada
NTS1; 2; 3; 10; 11; 12; 13; 14; 15; 16; 20; 21; 22; 23; 24; 25; 26; 27; 28; 29; 30; 31; 32; 33; 34; 35; 36; 37; 38; 39; 40; 41; 42; 43; 44; 45; 46; 47; 48; 49; 52; 53; 54; 55; 56; 57; 58; 59; 62; 63; 64; 65; 66; 67; 68; 69; 72; 73; 74; 75; 76; 77; 78; 79; 82; 83; 84; 85; 86; 87; 88; 89; 92; 93; 94; 95; 96; 97; 98; 99; 102; 103; 104; 105; 106; 107; 114O; 114P; 115; 116; 117; 120; 340; 560
AreaCanada; United States of America; Greenland; Denmark
Lat/Long WENS-141.5000 -20.0000 90.0000 41.0000
Subjectsgeophysics; magnetic anomalies; total field magnetics; structural trends; magnetic interpretations; geophysical interpretations
ProgramGSC Central Canada Division
Released2016 01 28
AbstractThe first vertical derivative of magnetic anomalies map of Canada shows small variations in the magnetic field. The derivative is calculated from the residual magnetic field and enhances the short wavelength component of the field. The magnetic character of a rock depends on its composition and its deformational and metamorphic history. To map these variations, the Geological Survey of Canada has been acquiring aeromagnetic data since 1947. Over the years, more than 500 surveys have been carried out, generally with a flight-line spacing of 800 m and an altitude of 305 m above the ground. These aeromagnetic surveys have been levelled to each other to correct for arbitrary datums, slow variations of Earth's magnetic field over time, and differing survey specifications. The dominant structural trends of geological provinces, truncation of those trends at structural boundaries, and the characteristic patterns of suture zones can be recognized on the magnetic anomaly map. The magnetic signature of Precambrian basement rocks can be seen through the Phanerozoic sedimentary basin cover. Major dyke swarms can be traced over hundreds of kilometres from their radiating linear magnetic pattern. Oceanic crust has a characteristic striped magnetic pattern that is due to changes in the polarity of Earth's magnetic field, which occur over intervals of millions of years.
Summary(Plain Language Summary, not published)
This map is a compilation of aeromagnetic surveys of Canada. Aeromagnetic surveys measure the total intensity of the earth's magnetic field. The field was measured by a magnetometer aboard an aircraft flown in parallel lines spaced at 200 m to 1600 m across the map area. The magnetic field reflects magnetic properties of bedrock and provides qualitative and quantitative information used in geological mapping. Understanding the geology will help geologists map the area, assist mineral/hydrocarbon exploration activities, and provide useful information necessary for communities, aboriginal associations, and government to make land use decisions. This survey was flown to improve our knowledge of the area. It will support ongoing geological mapping and resource assessment.

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