Spatial Digital Database for the Geologic Map of Oregon They are not designed to be cartographic products. The digital geologic map graphics and plot files that are provided in the digital package are representations of the digital database. This database is not meant to be used or displayed at any scale larger than 1:250,000 (for example, 1:100,000 or 1:24,000). Additionally, point features, such as strike and dip, were not captured from the original paper map and are not included in the database. Digital base map data files (topography, roads, towns, rivers and lakes, etc.) are not included they may be obtained from a variety of commercial and government sources. The resulting digital geologic map database can be queried in many ways to produce a variety of geologic maps. The database was created for use as a basemap in a decision support system designed by the National Industrial Minerals and Surface Processes project. ![]() Geological Survey staff and University of Arizona contractors at the Southwest Field Office, Tucson, Arizona, in 2000 for input into a geographic information system (GIS). ![]() The geologic map of the Tucson-Nogales 1:250,000 scale quadrangle (Peterson and others, 1990) was digitized by U.S. Geologic Map of the Tucson and Nogales Quadrangles, Arizona (Scale 1:250,000): A Digital Database Although users may view and analyze data at varying scales, the authors make no guarantee as to the accuracy of the data at scales larger than 1:750,000. All digital datasets were captured from source data at 1:750,000. Geologic unit polygon data were attributed for age, name, and lithologic type following the Lexico Estratigrafico de Venezuela. Feature classes in the geodatabase include geologic unit polygons, open water polygons, coincident geologic unit linework (contacts, faults, etc.) and non-coincident geologic unit linework (folds, drainage networks, etc.). Digital datasets and corresponding metadata files are stored in ESRI geodatabase format accessible via ArcGIS 9.X. Geological Survey Open-File Report 2005-1038. The digital geologic map and GIS database of Venezuela captures GIS compatible geologic and hydrologic data from the ' Geologic Shaded Relief Map of Venezuela,' which was released online as U.S. This standard will adhere generally to the accepted definitions and specifications for spatialĭigital geologic map and GIS database of Venezuela The new standard will track closely the latest developments of the Proposed Standard for Digital Cartographic Data soon to be submitted to the National Institute of Standards and Technology by the Federal Interagency Coordinating Committee on Digital Cartography. Such a coding system allows unique identification of as many as 105 geologic names and values on a given map. A proposed coding system comprises four-character groupings of major and minor codes that can identify all attributes of a geologic feature. Approximately 650 symbols for geoscience maps, including present usage of the U.S Geological Survey, state geological surveys, industry, and academia have been identified and tentatively adopted. Three primary issues were: (1) selecting scientific symbology and its digital representation (2) creating an appropriate digital coding system that characterizes geologic features with respect to their physical properties, stratigraphic and structural relations, spatial orientation, and interpreted mode of origin and (3) developing mechanisms for reporting levels of certainty for descriptive as well as measured properties. Geological Survey and the mandate of the National Geologic Mapping Program (with added representation from the Association of American State Geologists), a committee has been designing a comprehensive set of scientific map standards. Since December 1988, under commission of the Chief Geologic of the U.S. ![]() Application of earth-science data in complex geographic information systems, acceleration of geologic map production, and reduction of population costs require that national standards be developed for digital geologic cartography and computer analysis. Taylor, Richard B.Įstablishing modern scientific and technical standards for geologic maps and their derivative map products is vital to both producers and users of such maps as we move into an age of digital cartography. Toward digital geologic map standards: a progress report
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