USING THE NATIONAL GEOLOGIC MAP DATABASE AS A RESOURCE FOR GEOLOGIC MAPPING

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. The NGMDB system is a hybrid – some aspects are centralized and some are distributed, with the map information held by various cooperators (for example, the State geological surveys). Via the NGMDB website, users can browse and query its various databases, and obtain access to the source information wherever it resides.

Throughout the NGMDB project’s 15 years of operation, service to the general public has been a principal responsibility. Perhaps more pertinent to geologists who are making maps, the NGMDB also facilitates development of numerous resources to help them create maps more efficiently. 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, and a draft standard database design for publication of geologic maps (“NCGMP09”), 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 >85,000 publications by >370 publishers,, many containing GIS data and map images; (http://ngmdb.usgs.gov/ngmdb/ngm_catalog.ora.html);

4) a prototype Web service of georeferenced images of geologic maps of the Nation; and

5 Proceedings from the fourteen 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/).