Now offered in two formats (PDF and GeoTIF), Dibblee geologic maps contain observable, understandable, and reliable geological information of benefit to a broad range of users. They are printed on a USGS topographic map base in a consistent full color scheme at uniform scales of 1:24,000 and 1:62,500. The series depicts the geology of more than a quarter of California. PDF is the best choice for printing and should be the choice for most users. GeoTIF is the choice for users who want to pull a file into a GIS mapping application.