Map compiled by merging and PhotoShop editing layers from the National Atlas including:
Generalized geologic map of the United States: http://nationalatlas.gov/mld/geology.html [map layer compiled from unspecified USGS Geology Discipline resources]
Quaternary Faults and Fold Database of the United States: http://nationalatlas.gov/mld/qfaultm.html [map layer compiled from http://earthquakes.usgs.gov/regional/qfaults/]
Cities and Towns of the United States: http://nationalatlas.gov/mld/citiesx.html [map layer compiled from the USGS Geographic Names Information System (GNIS) and U.S. Census Bureau data]
Major Roads of the United States: http://nationalatlas.gov/mld/roadtrl.html [Map layer compiled from unspecified resources by the USGS in colaboration with the Federal Highway Administration (FHWA) and the U.S. Department of Transportation]
Grayscale United States Shaded Relief – 200 Meter Resolution: http://nationalatlas.gov/mld/srgy48i.html [map layer compiled from unspecified USGS resources]