Downloads and Documentation
About the USGS Thesaurus
Science Topics, a
component of the USGS home page, is a browsable index of web
resources intended for the public. It augments traditional search
and site-specific browse interfaces in concert with the
USGS by State and
About USGS sites,
and is specifically intended to work alongside those facilities.
This infrastructure is specifically intended to help people
outside USGS find information on USGS web sites without specific
knowledge of the organizational structure and operations of the
USGS. The interface design is based on the idea that finding
information cannot be separated from understanding, so in the
process of browsing or searching a user is assisted by seeing
relationships among scientific concepts, and learns while searching.
Underpinning this interface are several controlled vocabularies
structured as formal thesauri and authority lists, a catalog of
web resources appropriate for the intended audience, and
software used to create, review, and modify both the controlled
vocabularies and the catalog records. The system serves as an
example of the reapplication of classic library methodologies
in the web setting.
- Standards conformance
The USGS Thesaurus is the principal controlled vocabulary
supporting Science Topics. It is designed as a formal thesaurus
conforming to ANSI/NISO Z39.19, with rigid adherence to the
hierarchical (BT, NT) term relationships, generic non-hierarchical
(RT) relationships, and lead-in term relationships linking
non-preferred terms to descriptors either singly (UF) or in a
compound USE-WITH relationship. The thesaurus is faceted,
meaning its top terms delineate general aspects of information
- Major educational fields, fields of study, and professional groupings within USGS.
- Techniques, methods, procedures, or strategies for research, management, collection, or analysis of scientific information in USGS
- Themes, subjects, and concerns for which USGS information resources are relevant
- Product types
- General representation of the information in a resource, such as a map or data set
- Time periods
- Geologic time periods and seasons of the year
- Institutional structures and activities
- Activities, processes, and organizational concepts
- Level of detail
The thesaurus is limited in depth and specificity of
coverage. It does not attempt to replicate existing
controlled vocabularies such as AGI's GeoRef. The intention is
to provide sufficient contextual cues for the information
seeker to determine the relevance of a resource for his
or her concern, not to locate precisely the answer to a
specific user question.
Each information resource in the Science Topics catalog is
categorized using several index terms. Consequently a document
will be listed under each category for which it would be
considered a relevant resource. Approximately 2000 web
resources are listed in the catalog.
Questions and comments about the thesaurus or the USGS implementation of it
can be sent to GS_Thesaurus@usgs.gov.