The grids for this map in various formats are available from the data directory as mag4000.***
U.S. Department of the Interior | U.S. Geological Survey URL: https://pubsdata.usgs.gov/pubs/of/2000/ofr-00-0198/html/wy_4000.htm Questions or Assistance: USGS Web Contact Page Last Modified: Wed Dec 7 18:08 EST 2016