A marginal sea is a division of an ocean, partially enclosed by islands, archipelagos, or peninsulas, adjacent to or widely open to the open ocean at the surface, and/or bounded by submarine ridges on the sea floor.
Marginal seas of the Atlantic Ocean:
Argentine Sea
Cantabrian Sea
Caribbean Sea
English Channel
Gulf of Mexico
Hudson Bay
Irish Sea (separated by Ireland)
Iroise Sea
Labrador Sea
Mediterranean Sea
North Sea (by Great Britain)
Norwegian Sea (by Iceland, the Faroe Islands, and Shetland); and Greenland Sea
Scotia Sea (by the Falkland Islands and South Georgia and the South Sandwich Islands)
Marginal seas of the Indian Ocean:
Andaman Sea (separated by the Andaman and Nicobar Islands).
Arabian Sea
Bay of Bengal
Java Sea (separated by the Greater Sunda Islands)
Persian Gulf
Red Sea
Sea of Zanj (an historic entity off the southeast African coast and including the Mascarene islands)
Marginal seas of the Mediterranean Sea:
Adriatic Sea
Aegean Sea
Alboran Sea
Balearic Sea
Black Sea
Sea of Crete
Ionian Sea
Ligurian Sea
Myrtoan Sea
Sea of Sardinia
Sea of Sicily
Thracian Sea
Tyrrhenian Sea
Marginal sea of the Black Sea:
Sea of Azov
Marginal seas of the Pacific Ocean:
Bering Sea (separated by the Aleutian Islands)
Celebes Sea
Coral Sea (by the Solomon Islands and Vanuatu).
East China Sea (by the Ryukyu Islands)
Philippine Sea (by the Ogasawara Islands, the Mariana Islands, and Palau)
Salish Sea (separated by Vancouver Island)
Sea of Chiloé (by Chiloé Island, Chile)
Sea of Japan (also known as East Sea in Korea, by the Korean Peninsula and the Japanese Archipelago)
Sea of Okhotsk (by the Kurile Islands and Kamchatka Peninsula)
South China Sea (by the Philippines)
Sulu Sea
Tasman Sea (between Australia and New Zealand)
Yellow Sea (by the Korean Peninsula)
Marginal seas of the Southern Ocean:
Scotia Sea
The Caribbean Sea is sometimes defined as a marginal sea, sometimes as a mediterranean sea.
