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USGS (U.S. Geological Survey) National Geologic Map Database. General Information. Title: Magnetic anomaly map of North America Author(s): North American Magnetic ...
Product Description Page
USGS (U.S. Geological Survey) National Geologic Map Database. Check out the A preliminary, full spectrum, magnetic anomaly grid of the United States with improved long wavelengths for studying continental dynamics: a website for distribution of data. Map published by the U.S. Geological Survey .