877 articles
Abyssal plain
Abyssal plains are flat, sediment-covered deep-ocean floor at 3,000–6,000 m depth, covering roughly 30–70% of the seafloor depending on definition; they host polymetallic nodules targeted by deep-sea mining, notably in the Clarion-Clipperton Zone.
Active Sound
Active Sound (Estrecho Active) is a 17.5 km sound between Joinville and Dundee Islands, Antarctic Peninsula, charted 1892-93 by the Dundee Whaling Expedition and named for the barque Active.
Adie Inlet
Adie Inlet: ice-filled inlet of the Larsen Ice Shelf between Veier Head and Astro Cliffs, Oscar II Coast, Graham Land, at 66°25'S 62°20'W; about 40 km long; named 1947–51 for FIDS geologist Raymond Adie.
Admiralty Bay
Admiralty Bay, King George Island, South Shetland Islands, Antarctica: a glacial fjord bay opening to Bransfield Strait, about 120-150 km2, up to roughly 600 m deep, fed by twenty marine-terminating glaciers, designated ASMA No. 1 with Brazilian, Polish, and Peruvian stations.
Adriatic Sea
Adriatic Sea (Mare Adriatico, Jadransko more), arm of the Mediterranean between Italy and the Balkans, ~800 km long, 138,516 km², shallow north vs. 1,244 m deep south, bora/sirocco winds, Venice acqua alta, Po eutrophication.
Aegean dispute
Aegean dispute: long-running Greece-Turkey conflict over the Aegean Sea's continental shelf, EEZ, territorial waters, airspace, island demilitarization, and islet sovereignty, marked by the 1976 ICJ case, 1987 and 1996 crises, and the 2023 Athens Declaration.
Aegean Sea (Αιγαίο Πέλαγος)
The Aegean Sea (Greek Αιγαίο Πέλαγος, Turkish Ege Denizi) is an arm of the Mediterranean between Greece and Asia Minor, dotted with Greek islands and the cradle of early Greek civilization.
Agulhas Current
The Agulhas Current is the strong, warm western boundary current of the southwest Indian Ocean and the Southern Hemisphere's strongest, flowing along South Africa's east coast.
Agulhas Plateau
Agulhas Plateau, an oceanic large igneous province plateau in the Southwest Indian Ocean about 1000 km southeast of Cape Town; formed 100–94 Ma with Maud Rise and Northeast Georgia Rise at the Bouvet triple junction; overthickened 20 km oceanic crust; drilled by IODP Expedition 392.
Alaskan Coastal
Alaskan Coastal: the shoreline and marine zone of Alaska, the longest U.S. coastline at 66,000 miles, spanning five large marine ecosystems, major fisheries, and rapidly eroding permafrost coasts.
Albemarle Sound
Albemarle Sound is a large, shallow brackish lagoon in northeastern North Carolina, the northern part of the Albemarle-Pamlico Estuarine System behind the Outer Banks barrier islands.
Alboran Sea
Alboran Sea (mar de Alborán), westernmost Mediterranean basin between Spain, Morocco, and Algeria at the Strait of Gibraltar; known for its two-layer Atlantic-Mediterranean exchange, Alboran gyres, Almeria-Oran front, and Mediterranean biodiversity hotspot status.
Aleutian Basin
Aleutian Basin: deep-water (>3,000 m) oceanic basin of the Bering Sea north of the Aleutian Islands, about the size of Texas, with 2–9 km of Cenozoic sediment over Cretaceous oceanic crust; origin debated between Eocene plate capture and backarc spreading.
Aleutian Trench
The Aleutian Trench is a deep-ocean trench in the North Pacific where the Pacific Plate subducts beneath the North American Plate along the Aleutian island arc.
Algerian Basin
Algerian Basin (Algero-Balearic Basin): deep oceanic back-arc basin of the southern western Mediterranean between Algeria, the Balearic Islands and Sardinia, opened by 16 Ma, with the Algerian Current and its large eddies.
Alpha Ridge
Alpha Ridge: large submarine volcanic high in the Amerasian Basin, Arctic Ocean, part of the Alpha-Mendeleev Ridge complex; Late Cretaceous oceanic plateau linked to HALIP magmatism, ~38 km thick crust, ages 82-90 Ma.
Alum Bay
Alum Bay, Isle of Wight: bay at the island's western tip beside the Needles, famed for 21 shades of coloured sand, vertical Tertiary cliffs, its Elizabethan alum name, Marconi's 1897 radio station, and the Needles Landmark Attraction chairlift.
Ambush Bay
Ambush Bay, a bay on the north coast of Joinville Island, Antarctic Peninsula, east of King Point; named by the UK in 1957, formerly Bahía Carminatti, an Adélie penguin Important Bird Area.
Amerigo Vespucci
Amerigo Vespucci (Americo Vespucio), Florentine merchant-navigator ca. 1451–1512, recognized South America as a new continent; his voyages of 1499 and 1501–1502 underpinned Waldseemüller's 1507 map, which named America after him.
Amundsen Basin
Amundsen Basin: deep Arctic Ocean basin (~4,400 m) of the Eurasian Basin, between the Lomonosov and Gakkel ridges, named for Roald Amundsen; fresher Transpolar Drift surface water, NP-28 channel, MOSAiC drift start site.
Amundsen Gulf
Amundsen Gulf: Arctic embayment, 400 km long, between Banks Island and Canada's mainland coast, westernmost Northwest Passage entrance; named for Roald Amundsen, entered 1905; Cape Bathurst polynya.
Amundsen Sea
Amundsen Sea (Amundsenhavet), a marginal sea of the Southern Ocean off Marie Byrd Land, West Antarctica, named in 1929 for Roald Amundsen; warm Circumpolar Deep Water melts Thwaites and Pine Island ice shelves, driving Antarctic sea-level rise.
Ancylus Lake
Ancylus Lake was a freshwater lake stage in the postglacial Baltic Sea basin, following the Yoldia Sea and preceding the Littorina Sea, lasting roughly from 8800 to 6700 BC.
Andaman Basin
Andaman Basin: active back-arc basin in the NE Indian Ocean behind the Sunda subduction zone, extending ~1,250 km from Myanmar to Sumatra; spreading began ~4 Ma; Indian Category II frontier hydrocarbon basin with 371 MMTOE estimated resources.
Andaman Islands
The Andaman Islands is a large archipelago located in the Bay of Bengal, forming the union territory of India that encompasses the Nicobar Islands.
Andaman Sea
Andaman Sea, or Burma Sea, a ~790,000 km2 marginal sea of the eastern Indian Ocean between the Andaman-Nicobar Islands and Myanmar and Thailand, defined by IHO limits, monsoon-driven circulation, coral reefs, mangroves, seagrass, and the 2004 earthquake zone.
Andvord Bay
Andvord Bay: glaciomarine fjord on the Danco Coast, Western Antarctic Peninsula, in Gerlache Strait; ~20 km long, five tidewater glaciers, deep >400 m basins; FjordEco study site 2015-2017.
Angola Basin
Angola Basin (Ангольская Котловина), also Southeastern Atlantic Basin or Buchanan Deep: undersea basin of the eastern South Atlantic off Angola and Namibia, bounded by the Walvis Ridge, with Aptian salt, DSDP Leg 75 black shales, and a three-layer deep circulation.
Antarctic Circumpolar Current
The Antarctic Circumpolar Current, also known as the West Wind Drift, is the world's largest ocean current, flowing eastward around Antarctica and connecting the Atlantic, Pacific, and Indian Oceans.
Antarctic continental shelf
The Antarctic continental shelf is the deep (average 450 m, over 1,000 m in places), wide (~125 km) seabed around Antarctica, shaped by glacial overdeepening, source of Antarctic Bottom Water, and conduit for warm Circumpolar Deep Water toward ice shelves.