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National Spatial Data
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USGS
Geospatial Data Clearinghouse
National
Mapping and Remotely Sensed Data
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1:100,000-scale
Digital Line Graph (DLG)
Digital line graph (DLG) data are digital representations of cartographic information. DLG's of map features are converted to digital form from maps and related sources. Intermediate-scale DLG data are derived from USGS 1:100,000-scale 30- by 60-minute quadrangle maps. Intermediate-scale DLG's are sold in five categories: (1) Public Land Survey System; (2) boundaries (3) transportation; (4) hydrography; and (5) hypsography. All DLG data distributed by the USGS are DLG - Level 3 (DLG-3), which means the data contain a full range of attribute codes, have full topological structuring, and have passed certain quality-control checks. This is a data-set level implementation of the Federal Geographic Data Committee's Content Standards for Digital Geospatial Metadata.
Information about individual 100,000-scale DLG records can be obtained from the EROS Data Center.
Table
of Contents
Identification
Information (includes abstract)
Data Quality
Information
Spatial Data
Organization Information
Spatial
Reference Information
Entity and
Attribute Information
Distribution
Information (includes ordering information)
Metadata
Reference Information
Identification
Information
Identification_Information: Citation: Citation_Information: Originator: U.S. Geological Survey or another mapping agency in cooperation with USGS. Publication_Date: 19850101 Title: 1:100,000-scale Digital Line Graphs Publication_Information: Publication_Place: Reston, Virginia Publisher: U.S. Geological Survey Description: Abstract: Digital line graph (DLG) data are digital representations of cartographic information. DLG's of map features are converted to digital form from maps and related sources. Intermediate-scale DLG data are derived from USGS 1:100,000-scale 30- by 60-minute quadrangle maps. If these maps are not available, Bureau of Land Management planimetric maps at a scale of 1: 100,000 are used. Intermediate-scale DLG's are sold in five categories: (1) Public Land Survey System; (2) boundaries (3) transportation; (4) hydrography; and (5) hypsography. All DLG data distributed by the USGS are DLG - Level 3 (DLG-3), which means the data contain a full range of attribute codes, have full topological structuring, and have passed certain quality-control checks. Purpose: DLG's depict information about geographic features on or near the surface of the Earth, terrain, and political and administrative units. These data were collected as part of the National Mapping Program. Time_Period_of_Content: Time_Period_Information: Range_of_Dates/Times: Beginning_Date: 19870619 Ending_Date: Present Currentness_Reference: publication date Status: Progress: In work Maintenance_and_Update_Frequency: Irregular Spatial_Domain: Bounding_Coordinates: West_Bounding_Coordinate: -124.7333 East_Bounding_Coordinate: -067.9500 North_Bounding_Coordinate: 49.3833 South_Bounding_Coordinate: 24.5333 Keywords: Theme: Theme_Keyword_Thesaurus: None. Theme_Keyword: digital line graph Theme_Keyword: DLG Theme_Keyword: hydrography Theme_Keyword: transportation Theme_Keyword: boundaries Theme_Keyword: U.S. Public Land Survey System Theme_Keyword: hypsography Place: Place_Keyword_Thesaurus: U.S. Department of Commerce, 1977, Countries, dependencies, areas of special sovereignty, and their principal administrative divisions (Federal Information Processing Standard 10-3):Washington, D.C., National Institute of Standards and Technology. Place_Keyword: US Place_Keyword: CA Place_Keyword: MX Place_Keyword_Thesaurus: U.S. Department of Commerce, 1987, Codes for the identification of the States, the District of Columbia and the outlying areas of The United States, and associated areas (Federal Information Processing Standard 5-2):Washington ,D. C., National Institute of Standards and Technology. Place_Keyword: FIPS codes for states covered Access_Constraints: None Use_Constraints: None. Acknowledgement of the U.S. Geological Survey would be appreciated in products derived from these data.
Data
Quality Information
Data_Quality_Information: Attribute_Accuracy: Attribute_Accuracy_Report: Refer to Positional_Accuracy element. Logical_Consistency_Report: Topological requirements include: lines must begin and end at nodes, lines must connect to each other at nodes, lines do not extend through nodes, left and right areas are defined for each line element and are consistent throughout the file, and the lines representing the limits of the file (neatline) are free of gaps. The tests of logical consistency were performed by the USGS PROSYS program. The neatline was generated by connecting the four corners of the digital file, as established during initialization of the digital file. All data outside the enclosed region were ignored and all data crossing these geographically straight lines were clipped at the neatline. Data within a specified tolerance of the neatline were snapped to the neatline. Neatline straightening aligned the digitized edges of the digital data with the generated neatline, that is, with the longitude/latitude lines in geographic coordinates. All internal areas were tested for closure using PROSYS. Completeness_Report: For Digital Revision Status = Not revised Data completeness reflects the content of the source quadrangle. Features may have been eliminated or generalized on the source graphic, due to scale and legibility constraints. For Digital Revision Status = Limited Update This file has undergone limited update digital revision. The file contains only (1) those features that are photoidentifiable on monoscopic source, supplemented with limited ancillary source, and (2) those features, present on the original source quadrangle, that can not be reliably photoidentified but that are not considered particularly prone to change. For Digital Revision Status = Standard Update This file has undergone standard update digital revision. The data completeness of this file meets NMD standards for feature content. Positional_Accuracy: Horizontal_Positional_Accuracy: Horizontal_Positional_Accuracy_Report: For Digital Revision Status = Not revised: Vertical_Positional_Accuracy: Vertical_Positional_Accuracy_Report: For Hypsography and Hydrography Only: For Digital Revision Status = Not revised: Lineage: Source_Information: Source_Citation: Citation_Information: Originator: U.S. Geological Survey or another mapping agency in cooperation with USGS. Publication_Date: Unknown Title: The Topographic Map Names Data Base designation for the source quadrangle. Geospatial_Data_Presentation_Form: map Publication_Information: Publication_Place: Reston, Virginia Publisher: U.S. Geological Survey Source_Scale_Denominator: 100000 Type_of_Source_Media: stable-base material Source_Time_Period_of_Content: Time_Period_Information: Range_of_Dates/Times: Beginning_Date: 19870619 Ending_Date: Present Source_Currentness_Reference: ground condition Source_Citation_Abbreviation: MAP1 Source_Contribution: spatial and attribute information Process_Step: Process_Description: For Digital Revision Status = Not digitally revised: This Digital Line Graph was digitized from the USGS source quadrangle, by either the National Mapping Division, one of their cooperators, or one of their contractors. The digital data were produced by one of the following methods: - scanning a stable-based copy of the graphic materials. The scanning process captured the digital data at a scanning resolution of at least 0.001 inches; the resulting raster data were vectorized and then attributed on an interactive editing station. - scanning the paper map. The scanning process captured the digital data at a scanning resolution of at least 0.001 inches; the resulting raster data were vectorized and then attributed on an interactive editing station. - scanning a stable-based copy of the graphic materials. The resulting raster data were then manually digitized and attributed on an interactive editing station. The resolution of the digital data is at least 0.001 inches. - scanning the paper map. The resulting raster data were then manually digitized and attributed on an interactive editing station. The resolution of the digital data is at least 0.001 inches. - manually digitizing from a stable-based copy of the graphic material using a digitizing table to capture the digital data at a resolution of at least 0.001 inches; attribution was performed either as the data were digitized, or on an interactive edit station after the digitizing was completed. - manually digitizing from the paper map using a digitizing table to capture the digital data at a resolution of at least 0.001 inches; attribution was performed either as the data were digitized, or on an interactive edit station after the digitizing was completed. The determination of the DLG production method was based on various criteria, including feature density, feature symbology, and availability of production systems. Four control points corresponding to the four corners of the quadrangle were used for registration during data collection. An eight parameter projective transformation was performed on the coordinates used in the data collection and editing systems to register the digital data to the internal coordinates used in PROSYS, and a four parameter linear transformation was performed from the PROSYS internal coordinates to Universal Transverse Mercator (UTM) grid coordinates. The DLG data were checked for position by one or more of the following processes: - comparing plots of the digital data to the graphic source. - comparing the digital data to the digital raster scan. DLG data classification was checked by at least one of the following processes. - comparing plots of the digital data to the graphic source - comparing the digital data to the digital raster scan. Source_Used_Citation_Abbreviation: MAP1 Process_Date: Unknown
Spatial
Data Organization Information
Spatial_Data_Organization_Information: Indirect_Spatial_Reference: For Public Land Survey System: U.S. Department of the Interior, Bureau of Land Management: U.S. Public Land Survey System For Boundaries: U.S. Department of Commerce, 1977, Countries, dependencies, areas of special sovereignty, and their principal administrative divisions. (Federal Information Processing Standard 10-3): Washington,D.C., National Institute of Standards and Technology. U.S. Department of Commerce, 1987, Codes for the identification of the States, the District of Columbia and the outlying areas of The United States, and associated areas (Federal Information Processing Standard 5-2): Washington, D. C., National Institute of Standards and Technology. U.S. Department of Commerce,1990, Counties and equivalent entities of The United States, its possessions, and associated areas (Federal Information Processing Standard 6-4): Washington, D.C. National Institute of Standards and Technology. Direct_Spatial_Reference_Method: Vector
Spatial
Reference Information
Spatial_Reference_Information:
Horizontal_Coordinate_System_Definition:
Geographic:
Geographic_Coordinate_Units: Decimal degrees
Geodetic_Model:
Horizontal_Datum_Name: North American Datum of 1927
Ellipsoid_Name: Clarke 1866
Semi-major_Axis: 6378206.400000
Denominator_of_Flattening_Ratio: 294.978698
Entity
and Attribute Information
Entity_and_Attribute_Information: Overview_Description: Entity_and_Attribute_Overview: DLG3 attribute codes are used to describe the physical and cultural characteristics of DLG node, line, and area elements. Attribute codes are used to reduce redundant information, provide enough reference information to support integration with larger data base, and describe the relationships between cartographic elements. Each DLG element has one or more attribute codes composed of a three digit major code and a four-digit minor code. For example, with the 1: 24,000-scale DLG data, the line attribute code 050 0412 has a major code (050), meaning hydrography, with a minor code (0412) meaning stream. Entity_and_Attribute_Detail_Citation: U.S.Department of the Interior, U.S. Geological Survey, 1987 Digital Line Graphs from 1:100,000-Scale Maps--Data Users Guide 2; Reston, Virginia A hypertext extract is available at: URL: http://edc.usgs.gov/glis/hyper/guide/usgs_dlg Softcopies in ASCII, WordPerfect, and PostScript format are available at: URL: ftp://mapping.usgs.gov/pub/ti/DLG/ U.S.Department of the Interior, U.S.Geological Survey, 1990, Standards for Digital Line Graphs; Reston, Virginia Softcopies in ASCII, WordPerfect, and PostScript format are available at: URL: ftp://mapping.usgs.gov/pub/ti/DLG/
Distribution
Information
Distribution_Information: Distributor: Contact_Information: Contact_Organization_Primary: Contact_Organization: Earth Science Information Center, U.S.Geological Survey Contact_Address: Address_Type: mailing address Address: 507 National Center City: Reston State_or_Province: Virginia Postal_Code: 20192 Contact_Voice_Telephone: 1-888-ASK-USGS Hours_of_Service: 0800-1600 Contact_Instructions: In addition to the address above there are other ESIC offices throughout the country. A full list of these offices is at: URL: http://mapping.usgs.gov/esic/esic_index.html Resource_Description: 1:100,000-scale digital line graphs Distribution_Liability: Although these data have been processed successfully on a computer system at the U.S. Geological Survey, no warranty expressed or implied is made by the USGS regarding the utility of the data on any other system, nor shall the act of distribution constitute any such warranty. The Geological Survey will warrant the delivery of this product in computer-readable format, and will offer appropriate adjustment of credit when the product is determined unreadable by correctly adjusted computer input peripherals, or when the physical medium is delivered in damaged condition. Requests for adjustment of credit must be made within 90 day from the date of this shipment from the ordering site. Standard_Order_Process: Digital_Form: Digital_Transfer_Information: Format_Name: SDTS Format_Version_Date: 199207 Format_Specification: Topological Vector Profile Digital_Transfer_Option: Online_Option: Computer_Contact_Information: Network_Address: Network_Resource_Name: URL: http://edc.usgs.gov/glis/hyper/guide/100kdlgfig/states.html Online_Option: Computer_Contact_Information: Network_Address: Network_Resource_Name: URL:ftp://edcftp.cr.usgs.gov/pub/data/DLG/100K/ Offline_Option: Offline_Media: CD-ROM Recording_Format: ISO 9660 Compatibility_Information: This CD-ROM can be used with all computer operating systems that support CD-ROM as a logical storage device. All text files on the disc are in ASCII format. Data files are in ASCII or binary format. Digital_Form: Digital_Transfer_Information: Format_Name: DLG Format_Version_Date: 198805 Format_Specification: Optional Digital_Transfer_Option: Online_Option: Computer_Contact_Information: Network_Address: Network_Resource_Name: URL: http://edc.usgs.gov/glis/hyper/guide/100kdlgfig/states.html Online_Option: Computer_Contact_Information: Network_Address: Network_Resource_Name: URL: ftp://edcftp.cr.usgs.gov/pub/data/DLG/100K/ Offline_Option: Offline_Media: CD-ROM Recording_Format: ISO 9660 Compatibility_Information: This CD-ROM can be used with all computer operating systems that support CD-ROM as a logical storage device. All text files on the disc are in ASCII format. Data files are in ASCII or binary format. Offline_Option: Offline_Media: Cartridge Recording_Capacity: Recording_Density: 3480 Recording_Density_Units: megabytes Recording_Format: ASCII; available unlabelled or with ANSI-standard labels; available block sizes are multiples of 80 characters ranging from 8000 to 32720 characters. Offline_Option: Offline_Media: Cassette Recording_Capacity: Recording_Density: 8-mm High (4.5Gb) Recording_Density_Units: gigabytes Recording_Format: ASCII; available unlabelled or with ANSI-standard labels; available block sizes are multiples of 80 characters ranging from 8000 to 32720 characters. Offline_Option: Offline_Media: Cassette Recording_Capacity: Recording_Density: 8-mm Low (2.3Gb) Recording_Density_Units: gigabytes Recording_Format: ASCII; available unlabelled or with ANSI-standard labels; available block sizes are multiples of 80 characters ranging from 8000 to 32720 characters. Fees: The online copy of the data set (when available electronically) may be accessed without charge. For cartridge, cassette, and CD-ROM the costs are available at: URL: http://edc.usgs.gov/glis/hyper/order_info/prices#100KDLG Ordering_Instructions: Intermediate-scale DLG data are sold in 30-minute units that correspond to the east or west half of USGS 30- by 60-minute 1: 100,000-scale topographic quadrangle maps. Each 30-minute unit is produced and distributed as four 15- by 15-minute cells, except in high-density areas, where the 15-minute cells may be divided into four 7.5-minute cells. The transportation category of data includes major transportation systems collected in three separate overlays labeled: (1) Roads and Trails, (2) Railroads, and (3) Pipelines, Transmission Lines, and Miscellaneous Transportation Features. Although collected separately, the three files are distributed as a single unit. Orders for the transportation category for a given area will include all three files. Dataset searching and ordering capabilities are available through the Global Land Information System (GLIS) at: URL: http://edc.usgs.gov/webglis
Metadata
Reference Information
Metadata_Reference_Information: Metadata_Date: 199001 Metadata_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey Contact_Address: Address_Type: mailing address Address: 508 National Center City: Reston State_or_Province: Virginia Postal_Code: 20192 Contact_Voice_Telephone: 1 703 648 4543 Metadata_Standard_Name: Content Standards for Digital Geospatial Metadata Metadata_Standard_Version: 19940608 Metadata_Security_Information: Metadata_Security_Classification_System: None Metadata_Security_Classification: Unclassified Metadata_Security_Handling_Description: None
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Last modified: 29 June 1998