GeoRef contains over 2 million references to geoscience journal articles, books, maps, conference papers, reports, theses and dissertations. Covers the geology of North America from 1785 to the present and the geology of the rest of the world from 1933 to the present. The database includes references to all publications of the U.S. Geological Survey, and US Canadian theses in the geosciences.
To find maps using Georef, type in: [place name] AND maps (example: Harrisburg AND maps). If you want to limit to a certain type of map you can include terms such as geologic or topographic. More information on search techniques is available in the GeoRef help files.