Azores Platform

Azores Platform
Name	Azores Platform
Type	Submarine plateau
Location	North Atlantic Ocean
Coordinates	37°–40°N, 25°–33°W
Area	~500,000 km²
Depth	200–2,000 m
Geology	Basaltic plateau, seamounts, rifted crust
Age	Miocene–Holocene

Azores Platform The Azores Platform is a broad submarine plateau and domain in the North Atlantic situated between the Iberian Peninsula, Greenland, Cape Verde, and the British Isles. It lies proximate to the archipelago of the Azores (islands), the Mid-Atlantic Ridge, and the Gibraltar Strait corridor, and forms a key marine feature linking the European Plate, North American Plate, and African Plate. The platform influences circulation between the North Atlantic Current, Canary Current, and the Azores Current and shapes biodiversity corridors for taxa documented by institutions such as the Scripps Institution of Oceanography, the Natural History Museum, London, and the National Oceanic and Atmospheric Administration.

Geography and extent

The Azores Platform occupies roughly the area bounded by the Azores (islands), the Iberian Peninsula, the Mid-Atlantic Ridge, and the submarine terraces approaching Madeira (archipelago) and Cape Verde. Major physiographic elements include the Gorringe Bank, the Ampére Seamount, the Dacia Bank, and the Great Meteor Tablemount, as well as the shelf adjacent to the Portuguese Continental Shelf and the slope toward the Charlie-Gibbs Fracture Zone. Bathymetric surveys by the GEBCO project, the NOAA bathymetry program, and expeditions from the Woods Hole Oceanographic Institution have delineated ridges, abyssal plains, and seamount chains across the platform. Political jurisdictions that abut or overlap the platform include Portugal, Spain, and international waters administered under the United Nations Convention on the Law of the Sea.

Geological structure and composition

The platform consists of thick sequences of basaltic volcanic flows, pillow lava deposits, and intrusive gabbro bodies underlain by extended continental lithosphere and oceanic crust modifications. Stratigraphic units include Miocene submarine flood basalts correlated with exposures on São Miguel Island, Pico Island, and outcrops sampled during the Deep Sea Drilling Project and Ocean Drilling Program. Geochemical studies by teams from the University of Lisbon, the University of Azores, and the Institut Français de Recherche pour l'Exploitation de la Mer report enriched incompatible element patterns similar to parts of the Canary hotspot and distinct from the Iceland hotspot. Seismic reflection and refraction profiles collected by the British Geological Survey, GEOMAR Helmholtz Centre for Ocean Research Kiel, and the United States Geological Survey reveal layered sedimentary drape, mass-transport deposits, and carbonate buildups associated with the Terceira Rift.

Tectonic setting and formation

The platform formed through interactions among the Eurasian Plate, African Plate, and North American Plate and is closely connected to the transtensional regime of the Azores Triple Junction and the propagating rift systems such as the Terceira Rift and the Gibraltar Arc. Plate reconstructions incorporating data from the European Geosciences Union symposia, the Paleomap Project, and paleomagnetic analyses indicate episodic volcanism and uplift during the Neogene linked to mantle upwellings and lithospheric thinning. Structural features include transform faulting related to the Charlie-Gibbs Fracture Zone and oblique extension documented in surveys by the International Lithosphere Program. The Platetectonic evolution parallels episodes recognized in the Iberian Margin and the Rockall Plateau.

Volcanism and seismicity

Active and historic volcanism on the platform is expressed at submarine volcanoes and emergent central volcanoes on the Azores (islands), including eruptions recorded at Pico (mountain), Furnas, and Capelinhos; hydrothermal venting and gas emissions have been mapped near seamounts such as Konrád and Dom João de Castro Bank. Earthquake catalogs maintained by the Instituto Português do Mar e da Atmosfera, the USGS, and the European-Mediterranean Seismological Centre show seismic swarms associated with faulting along the Terceira Rift and strike-slip movement at the Azores Triple Junction. Geodetic campaigns using GPS (Global Positioning System), absolute bathymetry from ICESat, and marine magnetotelluric surveys indicate ongoing deformation, subsidence, and episodic uplift comparable to other volcanic plateaus like Iceland.

Oceanography and ecology

The platform modulates the pathways of the North Atlantic Current, the Azores Current, and the Portugal Current, contributing to mesoscale eddies and fronts that enhance productivity attracting pelagic species documented by the Monterey Bay Aquarium Research Institute, the European Marine Observation and Data Network, and fisheries records from the International Commission for the Conservation of Atlantic Tunas. Habitats include cold‑water coral gardens such as Lophelia pertusa mounds, sponge grounds, seagrass meadows near shallow banks, and hydrothermal communities resembling those described at Mid-Atlantic Ridge vents. Biodiversity surveys led by Biodiversity Research Institutes and museums have cataloged cetaceans including North Atlantic right whale migratory records, seabirds such as Cory's shearwater, and commercially important fish like Atlantic cod and European hake.

Human activity and resource use

Human uses encompass fisheries licensed by Portugal, scientific fishing cruises by institutions including the Fisheries and Oceans Canada collaborators, and maritime navigation along routes connecting Lisbon, Ponta Delgada, and transatlantic corridors used by vessels flagged to Malta and Panama. Mineral exploration for manganese nodules and polymetallic sulphides has attracted surveys funded by the International Seabed Authority and companies headquartered in United Kingdom and Norway. Energy interest includes proposed offshore wind and tidal proposals reviewed by the European Commission and seismic hazard assessments used by insurers like Lloyd's of London. Conservation measures overlap with proposals for marine protected areas advocated by Greenpeace and scientific consortia affiliated with the World Wildlife Fund.

Research history and exploration

Exploration began with 19th-century hydrographic work by the Royal Navy and surveys by the Instituto Hidrográfico de Portugal; systematic geological mapping advanced through the Deep Sea Drilling Project, the Ocean Drilling Program, and national oceanographic campaigns by the Institut Français de Recherche pour l'Exploitation de la Mer and the German Research Centre for Geosciences. Recent multidisciplinary programs include expeditions by the RRS James Cook, the RV Atlantis, and the RV Celtic Explorer integrating bathymetry, seismic profiling, and biological sampling. Major contributors to the literature include researchers from the University of Lisbon, the University of Azores, GEOMAR, Woods Hole Oceanographic Institution, and the National Oceanography Centre (UK), with findings published in journals such as Nature Geoscience, Geology (journal), and the Journal of Geophysical Research.

Category:Submarine plateaus