Area of Operations: Canada Basin, Amerasian Basin, United States, Canada, North America, Arctic Ocean
Dates: August 21, 2008 to October 03, 2008
Chief scientist: Deborah Hutchinson
H. Ruth Jackson, Geological Survey of Canada
Objectives: Collect multichannel seismic, sonobuoy, and single-beam echo sounder data as part of identifying the boundary of the U.S. extended continental shelf in the Amerasian (Canada) basin of the Arctic Ocean.
Type of Activity: Seismic profiling;
Information to be derived: Sediment thickness and geological history;
Summary: This cruise was a joint marine expedition between the Geological Survey of Canada and the United States Geological Survey, undertaken in the Canada Basin from the Canadian polar margin to the Northwind Ridge of the Chukchi Borderland. In this region ice conditions create conditions difficult for collecting underway geophysical information and a two-ship survey was required. The Canadian Coast Guard Ship LOUIS S. ST. LAURENT (LSSL) collected data in single ship mode during the period of August 21 to September 9, 2008. For the period of September 10 to 27 the United States Coast Guard Cutter HEALY accompanied the LSSL and contributed multibeam bathymetric data and high-resolution chirp sub-bottom profiler. The HEALY broke ice for the LSSL during seismic operations and the LSSL broke ice ahead of HEALY when multibeam was the important data set. The information was acquired in order to meet the requirements of Article 76 of the United Nations Convention on the Law of the Sea (UNCLOS) so that Canada can determine the boundaries of its extended continental shelf and for the United States to make a similar assessment. Data collected aboard LSSL were: 2817.1 km - multichannel seismic data; noise tests and signature tests; 85,664 - total shots fired; 12 - number of seismic lines; 4849 km - echo sounder (12 kHz) profiles; 181 - spot soundings from helicopter; 39 - total sonobuoys deployed; 4 - failed sonobuoys; 67 XCTDs - expendable CTDs for water column temperature and salinity (and velocity); 3 instances of shutting down the airguns for marine mammals (1 polar bear sighting, 2 seal sightings).
Contact: Deborah Hutchinson (dhutchinson@usgs.gov) PROJECT PARTNER ()
InfoBank: uses the identifier L-1-08-AR. Visit this site for more information.
Related Links: http://soundwaves.usgs.gov/2010/08/ http://soundwaves.usgs.gov/2008/07/outreach2.html http://www.thedailygreen.com/print-this/environmental-news/latest/arctic-sea-ice-47090304# http://www.usgs.gov/newsroom/article.asp?id=2013&from=sf http://www.ogj.com/display_article/338772/120/ARTCL/none/ExplD/1/US,-Canada-to-map-unexplored-Arctic-sea-floor,-USGS-says/ http://soundwaves.usgs.gov/2008/09/fieldwork2.html http://soundwaves.er.usgs.gov/2009/04/ http://www.sailwx.info/shiptrack/shipposition.phtml?call=CGBN
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