RESPONDING TO SOCIETAL NEEDS FOR GEOSCIENCE INFORMATION: THE NATIONAL GEOLOGIC MAP DATABASE

The USGS and the Association of American State Geologists (AASG) are mandated by Congress to provide a National Geologic Map Database (NGMDB, http://ngmdb.usgs.gov) of standardized, spatial geoscience information. This USGS-AASG partnership also involves collaboration with the Geological Survey of Canada, universities, and the private sector. To support both our external users and the geologic mappers and GIS specialists who prepare maps and databases, the NGMDB Project provides many online resources. For example: 1) the U.S. Geologic Names Lexicon ("GEOLEX"), a standard reference for the nation's stratigraphic nomenclature; 2) the Geoscience Map Catalog; and 3) Proceedings from the annual Digital Mapping Techniques workshops, which document map-preparation techniques, standards in use or in development by the nation's geological surveys, and data-capture techniques.

The NGMDB project's goal is to help users find the information they need to address a variety of societal and research applications. Society, businesses, and private citizens commonly are faced with complex, multi-dimensional issues; in order to facilitate the use of geologic information and its integration with other types of information, it must be presented in a form that is readily comprehensible. In other words, the presentation of basic and derivative geologic information must, to some extent, be standardized. Our agencies produce individual maps, reports, and datasets in a wide variety of formats and layouts, each containing specialized scientific terminology. Without a doubt, these have proven immensely valuable to our users. However, with the advent of GIS and Web services, our users demand access to a more integrated, comprehensive set of geologic maps and reports. With this in mind, the NGMDB project is working with U.S. and Canadian agencies to develop standards; these include a map data model, lithologic terminology, locational accuracy, and map symbology. These standards will be used in our prototype data portal, currently under development. In the portal, GIS data will be maintained in a distributed environment for query and data download. This prototype is intended to further promote standardization and cooperation among the geological surveys of the U.S., Canada, and other countries.