Identification_Information: Citation: Citation_Information: Originator: U.S. Geological Survey Publication_Date: 19991001 Title: Alexandra Mountains Geospatial_Data_Presentation_Form: Raster Data Publication_Information: Publication_Place: Rolla, MO Publisher: U.S. Geological Survey Description: Abstract: This non-standard Digital Raster Graphic (DRG) Product was produced by scanning, color mapping, georeferencing, and GeoTIFF conversion of a USGS Antarctic map. This DRG product includes collar information and is georeferenced to the Lambert Conformal Conic (LCC) projection. Purpose: A DRG is useful as a source or background layer in a GIS, as a means to perform quality assurance on other digital products, and as a source for the collection and revision of vector data. DRG's can also be merged with other digital data, for example, DEM's or DOQ's, to provide additional visual information for the extraction and revision of base cartographic information. This specific product was made for use in studies by the National Science Foundation (NSF). Supplemental_Information: The Product ID is 840671 The x,y coordinate position of pixel 1,1 is based on a specific LCC projection and has a x,y position of -103775, 125254 Time_Period_of_Content: Time_Period_Information: Range_of_Dates/Times: Beginning_Date: 1964 Ending_Date: 1966 Currentness_Reference: ground condition Status: Progress: Complete Maintenance_and_Update_Frequency: irregular Spatial_Domain: Bounding_Coordinates: West_Bounding_Coordinate: -156.000000 East_Bounding_Coordinate: -150.500000 North_Bounding_Coordinate: -77.000000 South_Bounding_Coordinate: -78.250000 Keywords: Theme: Theme_Keyword_Thesaurus: Antarctica DRG's Theme_Keyword: Digital Raster Graphic Theme_Keyword: Digital Antarctic Map Theme_Keyword: DRG Theme_Keyword: topographic map Theme_Keyword: special version DRG Place: Place_Keyword_Thesaurus: United States Board on Geographic Names, U.S. Geological Survey, 1995, Geographic Names of the Antarctic, 2nd edition, Reston, VA Place_Keyword: Antarctica Place_Keyword: Alexandra Mountains Access_Constraints: none Use_Constraints: Acknowledgment of the USGS would be appreciated in products derived from these data. Point_of_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: USGS Antarctic Resource Center Contact_Address: Address_Type: mailing address Address: 515 National Center Address: 12201 Sunrise Valley Drive City: Reston State_or_Province: VA Postal_Code: 20192 Contact_Voice_Telephone: 703 648-6010 Contact_Facsimile_Telephone: 703 648-5080 Contact_Electronic_Mail_Address: usarc@usgs.gov Data_Set_Credit: This DRG was produced by the U.S. Geological Survey in cooperation with the National Science Foundation. Please refer to the map collar in the image for cooperative agencies. Data_Quality_Information: Attribute_Accuracy: Attribute_Accuracy_Report: The Antarctic DRG is an 8-bit color image that may have up to 255 colors to represent features present on the Antarctic map. Attributes inherent in the symbology of the source remain the same in the DRG. Positional accuracy of individual pixels should generally be within three pixels(one pixel represents 25.4 meters on the DRG) of calculated position. Logical_Consistency_Report: not applicable Completeness_Report: This DRG is a faithfully reproduced digital image of the revised source map. Some differences may be detected between the source graphic used and the DRG due to the RGB values assigned to that particular color. The intent is to recreate those colors as closely as possible. Data completeness for DRG files reflects content of the source graphic. Features may have been eliminated or generalized on the source graphic due to scale and legibility constraints. For information on collection and inclusion criteria, see Topographic Mapping Methods For Antarctica by Geo. D. Whitmore and Rupert Southard, Jr., August 1964. Positional_Accuracy: Horizontal_Positional_Accuracy: Horizontal_Positional_Accuracy_Report: Information on the original datum of the published map is assumed to have been established by some form of Local Astronomic observation. Since the exact datum information is not available a WGS-84 has been used for this image. The image is cast on the LCC projection with standard parallels at 76.6667 and 79.3333 degrees South latitudes, which may be INCONSISTENT with map collar information. A special coordinate system has been generated specifically for this map. The longitude of origin for this map's reference system is the center of the map. The latitude of origin is 78 degrees south latitude. Lineage: Source_Information: Source_Citation: Citation_Information: Originator: U.S. Geological Survey Publication_Date: 1972 Title: Alexandra Mountains Geospatial_Data_Presentation_Form: map Publication_Information: Publication_Place: Reston, VA Publisher: U.S. Geological Survey Source_Scale_Denominator: 250000 Type_of_Source_Media: paper Source_Time_Period_of_Content: Time_Period_Information: Range_of_Dates/Times: Beginning_Date: 1964 Ending_Date: 1966 Source_Currentness_Reference: ground condition Source_Citation_Abbreviation: map1 Source_Contribution: spatial and attribute information Process_Step: Process_Description: The following describes procedures, instrumentation, hardware, and software used in the production of this non-standard Antarctic DRG. The process steps describe, in general, the method used at Mid-Continent Mapping Center to produce special version DRG's derived from scanning, georeferencing, and GeoTIFF conversion of an Antarctic USGS topographic map. 1. Production of this Antarctic DRG begins with the scanning of an Antarctic map (map1) on a high-resolution scanner. Scanning resolution is 500 dpi with the output file size of 20-150 mb. The color palette of the compressed DRG may be slightly modified to improve overall appearance. 2. The raw scan file is converted to TIFF format and the file size is reduced by converting the file to a PackBits compressed image. 3. The image is down sampled to produce a 250 dpi TIFF with an output resolution of 25.4 meters (83.3 feet). 4. An ASCII file of geographic coordinates is generated for all latitude/longitude grid intersections on the map. The geographic coordinates are then converted to meter coordinates, specific to the quad, using the parameters listed below: Projection: Lambert Conformal Conic (LCC) Datum: WGS-84 Standard Parallels: 76.6667 and 79.3333 degrees South Latitudes Latitude of Origin: 78 degrees South Longitude of Origin: Center of map 153 West Longitude 5. The meter coordinate system is then correlated to corresponding x,y points on the image file. 6. The entire image file(.tif) is projected using the meter coordinates as control. 7. The image is then reprojected using a WGS-84 Datum. 8. The WGS-84 file is ouput in Packbits compressed TIFF format with GeoTIFF tags populated. 9. A world file(.tfw) is generated. 10. Prior to archiving the DRG undergoes the following quality quality assurance procedures: a. All DRG files are inspected to ensure that they are geometrically consistent with normal map presentation. b. Each DRG is checked to ensure that data elements in the DRG metadata file correspond to the map collar information and to the information in the associated image file. c. Each DRG is checked for georeferencing accuracy by comparing the calculated values for latitude and longitude intersections with corresponding intersections in the DRG image. d. GeoTIFF header records in each DRG are checked for completeness and accuracy. e. Correct geographic transformation is verified on each image by comparing absolute ground control values to the positions of well defined points such as latitude/longitude intersections in the DRG image. Process_Date: 19991001 Spatial_Data_Organization_Information: Direct_Spatial_Reference_Method: raster Raster_Object_Information: Raster_Object_Type: pixel Row_Count: 7499 Column_Count: 8175 Spatial_Reference_Information: Horizontal_Coordinate_System_Definition: Planar: Map_Projection: Map_Projection_Name: Lambert Conformal Conic Lambert_Conformal_Conic: Standard_Parallel: -76.6667 Standard_Parallel: -79.3333 Longitude_of_Central_Meridian: -153 Latitude_of_Projection_Origin: -78.0 False_Easting: 0 False_Northing: 0 Planar_Coordinate_Information: Planar_Coordinate_Encoding_Method: row and column Coordinate_Representation: Abscissa_Resolution: 25.4 Ordinate_Resolution: 25.4 Planar_Distance_Units: meters Geodetic_Model: Horizontal_Datum_Name: WGS-84 Ellipsoid_Name: WGS-84 Semi-major_Axis: 6378137.0 Denominator_of_Flattening_Ratio: 298.3 Entity_and_Attribute_Information: Overview_Description: Entity_and_Attribute_Overview: Each raster entity or pixel contains a possible color index from 0 through 255 referencing a color palette of RGB values from 0 through 255. Due to the complexity of the DRG imagery no standard colors have been assigned to represent map features. Entity_and_Attribute_Detail_Citation: Noted in this metadata file. Distribution_Information: Distributor: Contact_Information: Contact_Organization_Primary: Contact_Organization: Customer Services, U.S. Geological Survey Contact_Address: Address_Type: mailing address Address: EROS Data Center City: Sioux Falls State_or_Province: SD Postal_Code: 57198 Contact_Voice_Telephone: 1 800 252 4547 Contact_Voice_Telephone: 1 605 594 6151 Contact_TDD/TTY_Telephone: 1 605 594 6933 Contact_Facsimile_Telephone: 1 605-594-6589 (24 hours) Contact_Electronic_Mail_Address: custserv@edcmail.cr.usgs.gov (24 hours) On-Line Inquiry Form Hours_of_Service: 0800-1600 CT Monday-Friday Distribution_Liability: Although these data have been processed successfully on a computer system at the USGS, no warranty expressed or implied is made by the USGS regarding the use of the data on any other system, nor does the act of distribution constitute any such warranty. The U.S. 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 days from the date of this shipment from the ordering site. Standard_Order_Process: Digital_Form: Digital_Transfer_Information: Format_Name: TIFF, GeoTIFF Format_Version_Number: 6.0, 0.2 File_Decompression_Technique: PackBits Digital_Transfer_Option: Offline_Option: Offline_Media: Compact Disc-Recordable (CD-R) Recording_Format: ISO 9660: DRG image files with corresponding world files and metadata files Fees: The online copy of the data set (when available electronically) can be accessed without charge. Fees for DRG's distributed on CD-R are subject to change. Call 1 800 252 4547 for current prices. Ordering_Instructions: For information about ordering DRG's on CD-R, contact EROS Data Center at 1 800 252 4547. Metadata_Reference_Information: Metadata_Date: 19991001 Metadata_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: Customer Services, U.S. Geological Survey Contact_Address: Address_Type: mailing address Address: EROS Data Center City: Sioux Falls State_or_Province: SD Postal_Code: 57198 Contact_Voice_Telephone: 1 800 252 4547 Contact_Voice_Telephone: 1 605 594 6151 Contact_TDD/TTY_Telephone: 1 605 594 6933 Contact_Facsimile_Telephone: 1 605-594-6589 Contact_Electronic_Mail_Address: custserv@edcmail.cr.usgs.gov (24 hours) On-Line Inquiry Form Metadata_Standard_Name: Content Standard for Digital Geospatial Metadata Metadata_Standard_Version: FGDC-STD-001-1998