Continental shelf and Territorial waters

Continental shelf noun - The relatively shallow (up to 200 meters) seabed surrounding a continent.

Territorial waters and continental shelf are semantically related in ocean floor by continent topic. In some cases you can use "Territorial waters" instead a noun phrase "Continental shelf".

Territorial waters noun - The waters surrounding a nation and its territories over which that nation exercises sovereign jurisdiction.

Continental shelf and territorial waters are semantically related in coastal waters topic. You can use "Continental shelf" instead a noun phrase "Territorial waters".