Canada's Program
Canada’s program is focused on the Atlantic and Arctic Oceans. There are no definite plans presently to collect information in the Pacific.
Key Parameters of Canada’s Continental Shelf Program
The key parameters required for the application of Article 76 of UNCLOS are bathymetry (the study of underwater depth and shape of the seabed) and seismic (a survey of the seabed using sound waves).
Scientific and Technical Guidelines, published by the UN Commission for the Limits of the Continental Shelf, also exist. These guidelines outline the requirements of the data that need to be used in defining the outer limits of the continental shelf.
More scientific and technical information can be obtained from the website of the Advisory Board on the Law of the Sea (ABLOS).
Atlantic
The continental shelf in the Atlantic Ocean encompasses a wide margin and therefore the applicationof Article 76 will provide an extended continental shelf. The result of the desktop study shows that an extended shelf could potentially exist along the entire margin from south of Nova Scotia into the Labrador Sea in the north (See figure 1).
Figure 1 - click to enlarge
In the summer of 2006, a bathymetry data collection survey was completed off the Grand Banks to determine the foot of slope and the 2500 metre depth contour (see figure 2).
Figure 2 - click to enlarge
In 2007, a seismic survey was done for the area offshore Nova Scotia and Newfoundland. The data acquired provided information on sediment thickness over the Sohm Abyssal Plain (see figure 3).
Figure 3 - click to enlarge
In the Labrador Sea, there is a potential for an extended continental shelf, as well as a possibility of an overlap between a Canadian extended shelf and one defined from Greenland.The area of interest to both Canada and Greenland (Denmark) is shown in figure 4.
Figure 4 - click to enlarge
Since the sediment thickness along the Labrador margin potentially allows for an extended continental shelf beyond 200 nautical miles, a seismic program has been planned for 2008.The 2008 program also includes a seismic survey to define the natural prolongation of the continental shelf in parts of the Grand Banks, such as Flemish Cap and Orphan Knoll.
The data collection in the Atlantic Ocean is planned to be finalized by the end of 2008. At that stage, the analysis of the data will start, with the defining of the foot of the slope from the bathymetry data and the interpretation of the seismic data.
Arctic
The Arctic is a geologically complicated area because of several submarine elevations. Data collection in such a remote area with the unpredictable weather and ice conditions is extremely difficult and challenging. Nevertheless, a desktop analysis has shown that the application of Article 76 of UNCLOS provides an extended shelf in the Canadian part of the Arctic Ocean (see figure 5).
Figure 5 - click to enlarge
Eastern Arctic
Analysis has also shown that according to Article 76 of UNCLOS the outer limit of the continental shelf in the eastern Arctic will mainly be defined through a combination of natural prolongation and the foot of the slope + 60 nautical miles formulae. Mainly deep crustal velocities and bathymetric data will therefore be required.
Figure 6 - click to enlarge
Canada and Denmark collaborated on a joint expedition in Lomonosov Ridge (see figure 6) which took place in March-May 2006 (LORITA experiment, see International Collaboration)
An on-ice bathymetric survey also took place in March 2007 from CFS Alert as a continuation of the data collection around the Lomonosov Ridge.
Western Arctic
In the western Arctic, the only way to define an extended continental shelf beyond 200 nautical miles according to Article 76 of UNCLOS is to apply the sediment formula, requiring the acquisition of the seismic information (see figure 7 for an outline of the general area).
Figure 7 - click to enlarge
A new seismic system was developed and, in the fall of 2006, the system was tested on a survey with the Canadian icebreaker, the CCGS Louis S. St-Laurent. This survey was done in the western Arctic and was intended primarily as a test of the ship and equipment, as well as for the purpose of sampling sediment thickness in different areas. The survey encountered different ice conditions and seismic data was collected along segments for a total length of 400 km.
As expected, the quality of the seismic recording depended heavily on the ice conditions and experience was gained on the towing and other parameters. In some areas, more than 3 seconds of sediment thickness was measured.
More bathymetry and seismic data was collected in the summer of 2007 using the CCSG Louis S. St-Laurent. Another collection of seismic data is planned in the Western Arctic for 2008-2009. The CCGS Louis S. St-Laurent and an escort icebreaker will be used.
Future Arctic programs
Figure 8 - click to enlarge
The overall plan for the Arctic program in the period 2007-2012 is shown in Figure 8.
Pacific
There are presently no definite plans to collect information in the Pacific Ocean. Because the Pacific margin is a so-called narrow margin, i.e. the shallow part of the continental shelf is narrow (much less that 200 nm wide), it is not likely that the standard application of Article 76 of UNCLOS will provide an extended continental shelf in this region.
