Suggested citation and version history for


  Causey, J. Douglas, 2007, revised 2011, Mining claim 
       activity on federal land in the United States:  U.S. 
       Geological Survey Data Series 290, v. 4.0 
       [http://pubs.usgs.gov/ds/2007/290/].


  Version 4.0, June 21, 2011
  Updated and expanded all states except Alaska.  

  Version 3.1, February 2, 2010
  Updated and expanded all states except Alaska.  Found minor 
  errors in the data files and applied small fixes throughout.

  Version 3.0, December 22, 2009
  Updated and expanded all states except Alaska.  The Nevada 
  data are newer than v. 2.1 because there are a few minor 
  changes to the metadata.  Otherwise it they not modified. 

  Version 2.1, July 28, 2009
  Updated and expanded the .zip data package for Nevada

  Version 2.0, December 18, 2008
  Mining claim statistics and shapefiles are updated (to 
    the end of 2007) with newer data obtained from BLM. All 
    the original data have been replaced with new data in 
    this version. 

  Version 1.1, April 25, 2008
  Updated and expanded the .zip data package for Nevada

  Version 1.0, November 20, 2007
  Initial release online at
  http://pubs.usgs.gov/ds/2007/290/