Metadata: Identification_Information: Citation: Citation_Information: Originator: Center for Coastal & Ocean Mapping, University of New Hampshire Publication_Date: March 2009 Title: ASCII xyz Multibeam soundings Data for Gulf of Alaska margin Description: Abstract: Full coverage, processed multibeam bathymetry soundings data - Data were reduced for position, elevation, orientation, water-column sound-speed and refraction effects and are provided in a cleaned fully integrated form in ASCII longitude, latitude, depth value. Purpose: The National Oceanic and Atmospheric Administration (NOAA), on behalf of the United States Government, has a requirement to carry out surveys of specific regions on the continental margin (slope and rise) in the U.S. Gulf of Alaska in order to obtain multibeam bathymetry. These data are required to support any potential claim for extended jurisdiction by the United States under United Nations Convention on the Law of the Sea (UNCLOS) Article 76. The requirement is for the collection and processing of full-coverage multibeam sonar data in water depths of approximately 2000 to 5000 m in order to precisely define the location of the 2500-m isobath and the "foot of the slope" as defined under UNCLOS Article 76. As part of their NOAA-funded research program, University of New Hampshire (UNH) researchers oversaw data acquisition, processing and archiving of the data collected during the cruise. Supplemental_Information: Information about UNH Center for Coastal and Ocean Mapping field activity are online at http://www.jhc.unh.edu/unclos/html/reports.htm. Time_Period_of_Content: Time_Period_Information: Range_of_Dates/Times: Beginning_Date: 2005 Ending_Date: 2005 Status: Progress: Complete Spatial_Domain: Bounding_Coordinates: West_Bounding_Coordinate: -144.600000 East_Bounding_Coordinate: -134.000000 North_Bounding_Coordinate: 60.000000 South_Bounding_Coordinate: 53.750000 Bouding_Coordinate_Units: Decimal Degree Keywords: Theme: Theme_Keyword_Thesaurus: Bathymetry Theme_Keyword: Multibeam Theme_Keyword: depth soundings Theme_Keyword: Bathymetry Theme_Keyword: ASCII xyz Theme_Keyword: Continental Slope Place: Place_Keyword: Continental Margin Place_Keyword: Gulf of Alaska Place_Keyword: Foot of the Slope Access_Constraints: None Use_Constraints: Please recognize the University of New Hampshire, Center for Coastal & Ocean Mapping (UNH/CCOM) as the source of this information. Point_of_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: for Coastal & Ocean Mapping, University of New Hampshire Contact_Person: James V. Gardner Contact_Position: Research Professor Contact_Address: Address_Type: Mailing and Physical Address Address: Chase Ocean Engineering Lab, 24 Colovos Road City: Durham State_or_Province: NH Postal_Code: 03824 Country: USA Contact_Voice_Telephone: 603-862-3473 Contact_Facsimile_Telephone: 603-862-0839 Contact_Electronic_Mail_Address: jim.gardner@unh.edu Hours_of_Service: 9 AM - 5 PM EST Security_Information: Security_Classification: Unclassified Data_Quality_Information: Attribute_Accuracy: Attribute_Accuracy_Report: A Kongsberg Simrad EM120 12-kHz multibeam sonar was used with effective beam widths no greater than 1° x 1° (fore-aft x athwart ships) at -3 dB, with swaths of 3.4 times water depth in water depths between 1000 and 5000 m, with depth accuracies of the swath of better than ±1% of water depth at these depths. All data meets this specification. Descriptions of the systems and offsets applied can be found within the cruise report at http://www.jhc.unh.edu/unclos/html/reports.htm. Positional_Accuracy: Horizontal_Positional_Accuracy: Horizontal_Positional_Accuracy_Report: Horizontal positioning of the vessel was determined using a NovAtel OEM2-3151R DGPS integrated with a POS/MV model 320 version 3 system. Positioning is accurate to better than ±5 meters (at 95% confidence) during all surveying. All positioning is referenced to the WGS84 Datum. Vertical_Positional_Accuracy: Vertical_Positional_Accuracy_Report: Depth errors (at the 95% confidence level) are smaller than ±1% of the observed water depth as determined by cross lines. Lineage: Process_Step: Process_Description: Individual soundings were extracted after data cleaning, formatted to ASCII xyz (longitude latitude depth) and compressed using WinZip. Process_Date: 2005 Process_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: Center for Coastal & Ocean Mapping, University of New Hampshire Contact_Person: James V. Gardner Contact_Position: Research Professor Contact_Address: Address_Type: Mailing and Physical Address Address: Chase Ocean Engineering Lab, 24 Colovos Road City: Durham State_or_Province: NH Postal_Code: 03824 Country: USA Contact_Voice_Telephone: 603-862-3473 Contact_Facsimile_Telephone: 603-862-0839 Contact_Electronic_Mail_Address: jim.gardner@unh.edu Hours_of_Service: 9 AM - 5 PM EST Spatial_Reference_Information: Horizontal_Coordinate_System_Definition: Planar: Map_Projection: Map_Projection_Name: unprojected geographic Coordinate_Information: Abscissa_Resolution: Ordinate_Resolution: Planar_Distance_Units: degrees Geodetic_Model: Horizontal_Datum_Name: WGS84 Ellipsoid_Name: WGS84 Semi-major_Axis: Denominator_of_Flattening_Ratio: Vertical_Coordinate_System_Definition: Depth_System_Definition: Depth_Datum_Name: Instantaneous Sea Level Depth_Resolution: Better than 1% of Water Depth Depth_Distance_Units: Meters Distribution_Information: Distributor: Contact_Information: Contact_Organization_Primary: Contact_Organization: Center for Coastal & Ocean Mapping, University of New Hampshire Contact_Person: James V. Gardner Contact_Position: Research Professor Contact_Address: Mailing and Physical Address Address: Chase Ocean Engineering Lab, 24 Colovos Road City: Durham State_or_Province: NH Postal_Code: 03824 Country: USA Contact_Voice_Telephone: 603-862-3473 Contact_Facsimile_Telephone: 603-862-0839 Contact_Electronic_Mail_Address: jim.gardner@unh.edu Hours_of_Service: 9 AM - 5 PM EST Distribution_Liability: These data not intended for navigational purposes. These data and information are provided with the understanding that they are not guaranteed to be usable, timely, accurate, or complete. Users are cautioned to consider carefully the provisional nature of these data and information before using them for decisions that concern personal or public safety or the conduct of business that involves substantial monetary or operational consequences. Conclusions drawn from, or actions undertaken on the basis of, such data and information are the sole responsibility of the user. Neither the University of New Hampshire nor any agency thereof, nor any of their employees, contractors, or subcontractors, make any warranty, express or implied, nor assume any legal liability or responsibility for the accuracy, completeness, or usefulness of any data, software, information, apparatus, product, or process disclosed, nor represent that its use would not infringe on privately owned rights. Standard_Order_Process: Digital_Form: Digital_Transfer_Information: Format_Name: binary File_Decompression_Technique: Winzip Transfer_Size: 424.1 MB compressed Metadata_Reference_Information: Metadata_Date: March 2009 Metadata_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: Center for Coastal & Ocean Mapping, University of New Hampshire Contact_Person: James V. Gardner Contact_Position: Research Professor Contact_Address: Mailing and Physical Address Address: Chase Ocean Engineering Lab, 24 Colovos Road City: Durham State_or_Province: NH Postal_Code: 03824 Country: USA Contact_Voice_Telephone: 603-862-3473 Contact_Facsimile_Telephone: 603-862-0839 Contact_Electronic_Mail_Address: jim.gardner@unh.edu Hours_of_Service: 9 AM - 5 PM EST Metadata_Standard_Name: FGDC Content Standards for Digital Geospatial Metadata Metadata_Standard_Version: FGDC-STD-001-1998 Metadata_Time_Convention: Universal Time Metadata_Security_Information: Metadata_Security_Classification: Unclassified