The grids for this map in various formats are available from the data directory as tuc50mag.***
U.S. Department of the Interior
U.S. Geological Survey
This page is <URL: https://greenwood.cr.usgs.gov/pub/open-file-reports/ofr-01-0081/html/arizona.htm>
Maintained by: Gene Ellis
Last Modified Monday, 15-May-2000
For more information about this report contact: Ron Sweeney