Seismic subbottom data collected on cruise Kilo Moana KM0514 in the UNCLOS ECS Gulf of Alaska continental marginGulf of Alaska continental margin

Knudsen 320BR subbottom seismic data collected on RV Kilo Moana cruise 0514 on the U.S. margin in the Gulf of Alaska, north Pacific Ocean. The National Oceanic and Atmospheric Administration (NOAA), on behalf of the United States Government, has a requirement to carry out mapping surveys of specific regions on the margins in the Gulf of Alaska, north Pacific Ocean in order to determine the detailed bathymetry of the margins. The 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 1000 to 5500 m in order to precisely define the location of potential natural prolongations to the continent as defined under UNCLOS Article 76. As part of the NOAA-funded research program, University of Hawaii researchers oversaw data acquisition, and University of New Hampshire (UNH) researchers performed the cruise planning and oversaw processing and archiving of the data collected during the cruise. A full patch test was conducted in deep water in the immediate area prior to commencement of mapping. New sound-speed profiles were collected by 106 XBT casts whenever the sound speed at the transducer differed by more than 0.5 m/s. Positions were determined by corrected differential GPS-aided inertial navigation. Sound-speed profiles were calculated from an XBT cast calibrated to an CTD cast during a patch test performed on the cruise prior to data collection. Horizontal_Positional_Accuracy_Report: Horizontal positioning of the vessel was determined using Applanix POS/MV 320 inertial motion unit (IMU) version 3 was interfaced to a NovAtel OEM2-3151R global positioning system (GPS). Positioning is accurate to better than 0.5 meters (at 95% confidence) during all surveying. All positioning is referenced to the WGS84 Datum. Process_Description: Raw data were recorded standard SEGY format. Depth units: meters Reference ellipsoid: WGS-84 Projection: unprojected geographic longitude, latitude Vertical reference: instantaneous sea level. Cruise report available at http://ccom.unh.edu/sites/default/files/publications/Gardner_05_cruise_report_KM0514.pdf.