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Scientists Set Sail to Map the Arctic Seafloor

Scientists Set Sail to Map the Arctic Seafloor

American and Canadian scientists are setting sail this summer to map the Arctic seafloor and gather data to help define the outer limits of the continental shelf.

Each coastal nation may exercise sovereign rights over the natural resources of their continental shelf, which includes the seabed and subsoil. These rights include control over minerals, petroleum, and sedentary organisms such as clams, crabs and coral.

Under international law, specifically the United Nations Convention on the Law of the Sea, every coastal nation automatically has a continental shelf out to 200 nautical miles or to a maritime boundary. The Convention also states that a nation is entitled to continental shelf beyond 200 nautical miles if certain criteria are met, an area that is referred to as the “extended continental shelf.”

Related Podcasts
U.S. – Canada Arctic Expedition
Surveying the Extended Continental Shelf

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The U.S. Geological Survey is the lead science agency for the United States in the 2010 mission. “In this expedition, Canada and the U.S. are working together to delineate the extended continental shelf in the Arctic to better determine where the Convention’s criteria can be met,” said USGS scientist Brian Edwards, chief scientist on the U.S. Coast Guard Cutter Healy.

The Healy will sail August 2 – September 6, 2010, meeting up with the Canadian Coast Guard Ship Louis S. St-Laurent at sea.

The ships will alternately break through the Arctic sea ice for each other. The Healy will map the shape of the seafloor using a multibeam echo sounder, and the Louis S. St-Laurent will collect multi-channel seismic reflection and refraction data to determine sediment thickness.

This is the third year the United States and Canada have collaborated in extended continental shelf data collection in the Arctic. The United States has independently been collecting single ice-breaker data in the Arctic since 2003 in furtherance of the U.S. Extended Continental Shelf Project.

“The Arctic Ocean is an area of great interest for science, resource conservation, and possible economic development,” said USGS scientist Deborah Hutchinson. “Because there is an area with considerable overlap between the U.S. and Canadian extended continental shelves, it makes sense to share data sets and work together in the remote and challenging environments of the Arctic Ocean.”

“This is the last year working in the Canada Basin north of Alaska, and in 2011, we’ll collect data together with Canada in the area north of the Canada Basin around the Alpha Ridge,” said USGS scientist Jonathan Childs, who is leading the U.S. Interagency Task Force Seismic Data Operations Team.

Research is coordinated by the U.S. Extended Continental Shelf Task Force, a government-wide group headed by the U.S. Department of State. Participants in this Task Force include the U.S. Department of the Interior, U.S. Geological Survey, National Oceanic and Atmospheric Administration, U.S. Coast Guard, National Science Foundation, Joint Chiefs of Staff, U.S. Navy, U.S. Department of Energy, U.S. Environmental Protection Agency, Executive Office of the President, Minerals Management Service and the Arctic Research Commission.

For additional information on this expedition as well as photographs and video from past cruises, visit the Extended Continental Shelf Project or the Sound Waves April 2009 Newsletter.

Visit Canada’s Extended Continental Shelf website to learn more. 

Information on the United Nations Convention on the Law of the Sea can be found online

USGS Newsroom

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Parameter Value Description
Magnitude mb The magnitude for the event.
Longitude ° East Decimal degrees longitude. Negative values for western longitudes.
Latitude ° North Decimal degrees latitude. Negative values for southern latitudes.
Depth km Depth of the event in kilometers.
Place Textual description of named geographic region near to the event. This may be a city name, or a Flinn-Engdahl Region name.
Time 1970-01-01 00:00:00 Time when the event occurred. UTC/GMT
Updated 1970-01-01 00:00:00 Time when the event was most recently updated. UTC/GMT
Timezone offset Timezone offset from UTC in minutes at the event epicenter.
Felt The total number of felt reports
CDI The maximum reported intensity for the event.
MMI The maximum estimated instrumental intensity for the event.
Alert Level The alert level from the PAGER earthquake impact scale. Green, Yellow, Orange or Red.
Review Status Indicates whether the event has been reviewed by a human.
Tsunami This flag is set to "1" for large events in oceanic regions and "0" otherwise. The existence or value of this flag does not indicate if a tsunami actually did or will exist.
SIG A number describing how significant the event is. Larger numbers indicate a more significant event.
Network The ID of a data contributor. Identifies the network considered to be the preferred source of information for this event.
Sources A comma-separated list of network contributors.
Number of Stations Used The total number of Number of seismic stations which reported P- and S-arrival times for this earthquake.
Horizontal Distance Horizontal distance from the epicenter to the nearest station (in degrees).
Root Mean Square sec The root-mean-square (RMS) travel time residual, in sec, using all weights.
Azimuthal Gap The largest azimuthal gap between azimuthally adjacent stations (in degrees).
Magnitude Type The method or algorithm used to calculate the preferred magnitude for the event.
Event Type Type of seismic event.
Event ID Id of event.
Event Code An identifying code assigned by, and unique from, the corresponding source for the event.
Event IDS A comma-separated list of event ids that are associated to an event.

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