Obtaining Digital Maps
Large-scale digital maps of the Puget Sound aeromagnetic survey can be downloaded from the directory, maps. Individual maps are available for the entire aeromagnetic survey and for all 1:100000-scale quadrangles covered by the survey. The maps show the intensity of the magnetic field (expressed in nanotesla) as colored shaded-relief. Warm colors indicate anomalously high magnetic intensity; cool colors anomalously low intensity. The maps also show coastlines, major cities, and major inland water bodies.
Maps are in Portable Document Format (PDF) and can be viewed and printed using Adobe Reader. Adobe Reader is a free program available from Adobe Systems Incorporated (http://www.adobe.com). PDF is described more fully in this "readme" file.
To speed file transfers, all maps have additionally been compressed into the public-domain "gzip" format (as indicated by the suffix .gx). Gzip format is commonly used on PC DOS, PC Windows, Macintosh, and Unix platforms. It too is described more fully in the "readme" file.