the.com/continental shelf

The shallow, drowned edge of a continent, pretending the ocean starts later than it does.

means The gently sloping, shallow seabed that fringes a continent before the ocean floor drops away steeply into the deep sea.

from A 19th/20th-century scientific compound, not a folk tale: 'continental' from Latin 'continens' (holding together, continuous land), and 'shelf' from a Germanic word for a flat ledge or plank. Geologists and oceanographers bolted the two together once sounding surveys revealed that continents don't simply end at the coastline — they keep going underwater as a shallow ledge before plunging down the continental slope to the true ocean floor.

actual boundary
Ends at the shelf break, not the coastline
legal reach
Countries can claim rights 200 nautical miles out
resource jackpot
Holds most of the world's offshore oil and fish
depth logic
Usually under 200 meters, then plunges sharply
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