The National Geologic Map Database -- a brief project description (written at the project's inception in 1995)

-- An Internet-based system for query and retrieval of earth-science map information.

(Project Chief -- Dave Soller, 703-648-6907)

Geologic maps, derivative maps, and related information serve a vital role in supporting public and private decision-making, general education, and advances in scientific research. Such information, however, is located at many agencies and institutions, and is not readily accessible to many people. Optimal use of the information, and increased use by organizations and decision makers who do not ordinarily rely on earth-science information, requires that map information from any and all sources be made readily available to each user. The National Geologic Mapping Act of 1992 (PL102-285 and 43 USC sections 31a-h) specified that the USGS develop a National Geologic Map Database as a national archive containing geologic maps and related databases. The Act stated that the Database was to be developed as soon as practicable, through "...cooperation with State geological surveys, other Federal and State agencies, public and private sector organizations, and academia." The Database must contain geologic, geophysical, geochemical, geochronologic, and paleontologic information.

The Database will serve as the central archive or point-of-contact for users searching for earth-science information. It is intended to fulfill several functions including: a catalog of available map information for perusal and searching; a data repository; and a source for general information on the nature and intended uses of the various types of earth-science information. To address these functions, coordination will be required among the many agencies and institutions that produce earth-science information. The USGS has been identified as the agency responsible to ensure coordination.

Development of the Database is further supported by Executive Order 12906, signed in 1994. That Order established the National Spatial Data Infrastructure (NSDI), which will include a National Spatial Data Clearinghouse. The Clearinghouse will help users find information by performing keyword or geographic searches of metadata (brief descriptions of individual data sets). The president's executive order specifies that standards will be developed by the Federal Geographic Data Committee (FGDC). Those standards will facilitate the efficient search, transfer, and use of both metadata and the actual data sets. Subcommittees (each focusing on a specific subject, such as cadastral records, soils, or geology) will work to improve the sharing of information in part by developing standards. The USGS chairs the Geologic Data Subcommittee. Subcommittee and Database activities will be coordinated.

A conceptual design for the Database has been developed (see publication in June, 1995 issue of Geotimes). It is based on consensus that a distributed system is the most practical one. The distributed system will be composed of many computers where the metadata and the data and interpretive information are stored (on fileservers) but with a single national point of public access for browsing and query. The system can include map information, metadata, and fileservers at the USGS and other Federal agencies, state geological surveys, tribal governments, local governments, academic institutions, and the private sector. A coordinated, national perspective to the Database will be maintained through centralized management at the USGS.

The central component of the Database will be a catalog of metadata, searchable over the Internet. This catalog will provide the user with the information needed to assess the availability and utility of earth-science information in their area of interest.

Public and private decisions that require map information are, increasingly, based on the analysis of digital information. Because map information in digital format will be requested by many users, the Database will develop and manage digital data sets. However, because the majority of geologic maps are in paper format, the on-line, searchable catalog of metadata that describes available map information will remain an important component of the Database.

This project will manage the Database and will be responsible for the computer interface and the catalog search protocols. The Database will be built through cooperation with the state geological surveys, and with other entities who participate (e.g,. Federal agencies, tribal governments, local governments, universities, and private corporations) pending approval by the USGS and the state geological surveys. All participants will adhere to standards for content and format agreed to by the USGS and the state geological surveys in collaboration with the FGDC. Participation by the state geological surveys will be coordinated by their representative body, the Association of American State Geologists, through its Data and Standards Committee. That Committee will work directly with the USGS Database team to help design the Database, develop standards, ensure adherence to standards, ensure that metadata are created for both paper and digital maps and related information produced by each organization, ensure that metadata are delivered to the central search computer, and identify data sets that can be made available for copying across the Internet.

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