Special geographical characteristics of Sri Lankan continental shelf in extending seabed rights beyond 200 nautical mile- limit in pursuant to the United Nations Convention on the Law of the Sea (UNCLOS)

Abstract

The national development of Sri Lanka is inevitably tied to its marine resources within the Exclusive Economic Zone (EEZ) and beyond the EEZ; legal continental shelf. United Nations Convention on the Law of the Sea (UNCLOS) provides the necessary legal framework to extend the legal continental shelf rights beyond 200 M limits. Owing to unique geographical characters of the Bay of Bengal, a special set of rules is provided in Statement of Understanding (SOU), Annex II, Final Act to UNCLOS III, in establishing extended legal continental shelves for the Coastal States in the southern part of the Bay of Bengal. In adopting the SOU, as one of the requirements, such coastal states has to confirm that “the average distance at which the 200 meter isobath occurs is not more than 20 nautical miles” (SOU, Para 1). In fulfilling the above requirement for Sri Lanka, bathymetry data of near offshore has been collected and compiled to a database. GEBCO, one minute grid, has been considered as the primary data layer in building up of the database. Besides of the GEBCO database, bathymetry from single channel seismic cruises and surveys conducted for petroleum resources along with the Admiralty Charts were taken into account. Collected data were analyzed both in Geocap and Geosoft packages and the output map was synthesized with ArcGis facilities. Distance to the 200m isobath was calculated from corresponding basepoints and the averaged value was determined. The final results proved that the average distance to the 200m isobath from the basepoints is 10.5m. This analysis assures that Sri Lanka fulfills this requirement; a presence of a narrow continental shelf, which is one of special characters to adopt Statement Of Understanding (SOU) as costal state in the southern part of the Bay of Bengal.