USING THE NATIONAL GEOLOGIC MAP DATABASE AS A RESOURCE FOR DIGITAL MAP PRODUCTION

The USGS and the Association of American State Geologists are mandated by Congress to provide a National Geologic Map Database (NGMDB) of standardized, spatial geoscience information. In this partnership, collaboration occurs with the private sector, universities, and geological survey agencies in other countries. From the public website (http://ngmdb.usgs.gov) we serve one of our principal user communities – the professional geologists and non-geologists who need to find geologic maps and geoscience reports, and get answers to their questions. Throughout the NGMDB project's 12 years of operation, service to the general public has been a principal responsibility.

More pertinent to geologists who are making maps, the NGMDB also provides numerous resources that can help them create maps more efficiently. We have found that while working together on this Database and the standards that support it, the state geological surveys and USGS also have improved their own ability to deliver geologic map and related products to their users. Online resources provided by, or linked from, the NGMDB include:

1) cartographic, database design, science terminology, and data-exchange standards (for example, the FGDC geologic map symbol standard and its implementation in ESRI software; http://ngmdb.usgs.gov/Info/standards/);

2) the U.S. Geologic Names Lexicon (GEOLEX; http://ngmdb.usgs.gov/Geolex/geolex.html), a standard reference for the nation's stratigraphic nomenclature;

3) the Geoscience Map Catalog (containing citations and links to ~81,500 publications, many containing GIS data and map images; http://ngmdb.usgs.gov/ngmdb/ngm_catalog.ora.html); and

4) Proceedings from the twelve annual Digital Mapping Techniques workshops, which document map-preparation techniques and standards in use or in development by the nation's geological surveys (http://ngmdb.usgs.gov/Info/dmt/).