GMEG - Geology and Geophysics
The U.S. Geological Survey has produced geologic maps since its earliest days. Over time, methods of investigation, presentation, and interpretation have changed significantly. Today, maps are produced in an array of digital formats using geographic information systems (GIS) that can be used to produce traditional "flat" geologic maps for printing, or can be used for more technical, interactive data modeling. Digital geologic information can be combined with data sets including satellite or radar imagery, biology, water, weather, social infrastructure, epidemiology, population census, or practically any other kind of spatial data.
See these geologic mapping websites:
What Is a Geologic Map? (Geologic Maps and Mapping website)
http://ngmdb.usgs.gov/ncgmp/ncgmpgeomaps/
Use this website to learn how to interpret geologic maps, and other types of maps that show geophysical, geochemical, and paleontological information.
The National Geologic Map Database
http://ngmdb.usgs.gov/
This website a resource for locating geologic maps of any location in the United States.
Additional educational resources compiled by G & G scientists can be found at:
USGS Educational Resources
http://education.usgs.gov