Magnetic Anomaly Map of North America
The digital magnetic anomaly database and map for the North American continent is the result of a joint effort by the Geological Survey of Canada (GSC), U.S. Geological Survey (USGS), and Consejo de Recursos Minerales of Mexico (CRM). This integrated, readily accessible, modern digital database of magnetic anomaly data is a powerful tool for further evaluation of the structure, geologic processes, and tectonic evolution of the continent and may also be used to help resolve societal and scientific issues that span national boundaries. The North American magnetic anomaly map derived from the digital database provides a comprehensive magnetic view of continental-scale trends not available in individual data sets, helps link widely separated areas of outcrop, and unifies disparate geologic studies.
The group created three unique, gridded data sets used to make the magnetic anomaly map of North America. Details on the data processing and compilation procedures used to produce the grids are described in the booklet that accompanies the North American magnetic anomaly map. The first grid shows the magnetic field at 305 meters above terrain. For the second grid we removed long-wavelength anomalies (500 km and greater) from the first grid. This grid was used for the published map. The third grid uses an equivalent source method, based on long-wavelength characterization using satellite data, to correct for spurious shifts in the original magnetic anomaly grid. Further details on the grids are described in the open-file report listed below.
|Viki Bankey||Patricia Hill||Victoria Rystrom|
|Alejandro Cuevas||Robert Kucks||Sarah Shearer|
|David Daniels||Warner Miles||Stephen Snyder|
|Carol A. Finn||Mark Piulkington||Ronald Sweeney|
|Israel Hernandez||Carter Roberts||Julio Velez|
Outline of North American continent with identifiers for Canadian, U.S., and Mexican participating agencies.
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DVD: Available after November 2002 from USGS Information Services