Water Resources Division, U.S. Geological Survey 2001 Each year the U.S. Geological Survey (USGS) produces thousands of new and revised topographic and geologic maps, as well as other types of cartographic products. To provide easy access to these maps, the USGS publishes indexes that are updated periodically. application/pdf 10.3133/fs13401 en Geological Survey (U.S.) Map Indexes Available from the U.S. Geological Survey reports