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The Great Meteor Seamount, also called the Great Meteor Tablemount, is a
guyot In marine geology, a guyot (), also called a tablemount, is an isolated underwater volcanic mountain (seamount) with a flat top more than below the surface of the sea. The diameters of these flat summits can exceed . Guyots are most commonly fo ...
and the largest
seamount A seamount is a large submarine landform that rises from the ocean floor without reaching the water surface (sea level), and thus is not an island, islet, or cliff-rock. Seamounts are typically formed from extinct volcanoes that rise abruptly a ...
in the North Atlantic with a volume of . It is one of the
Seewarte Seamounts The Seewarte Seamounts, also known as the Seewarte Seamount Chain, Atlantis-Great Meteor Seamount Chain and the Atlantis-Plato-Cruiser-Great Meteor Seamount Group, is a north-south trending group of extinct submarine volcanoes in the northern Atla ...
, rooted on a large terrace located south of the
Azores Plateau The Azores Plateau or Azores Platform is an oceanic plateau encompassing the Azores archipelago and the Azores triple junction in the North Atlantic Ocean. It was formed by the Azores hotspot 20 million years ago and is still associated w ...
. The crust underlying Great Meteor has an age of 85 million years, deduced from the magnetic anomaly 34 (An34) at this location. The shallow and flat summit of the Great Meteor Seamount, ranging between below sea level, suggests that it may have emerged sometime in the past 30 million years. It is covered by a thick layer of
limestone Limestone is a type of carbonate rock, carbonate sedimentary rock which is the main source of the material Lime (material), lime. It is composed mostly of the minerals calcite and aragonite, which are different Polymorphism (materials science) ...
,
pyroclastic rock Pyroclastic rocks are clastic rocks composed of rock fragments produced and ejected by explosive volcanic eruptions. The individual rock fragments are known as pyroclasts. Pyroclastic rocks are a type of volcaniclastic deposit, which are deposit ...
s and
bioclast Bioclasts are skeletal fossil fragments of once living marine or land organisms that are found in sedimentary rocks laid down in a marine environment—especially limestone varieties around the globe, some of which take on distinct textures and col ...
ic
sandstone Sandstone is a Clastic rock#Sedimentary clastic rocks, clastic sedimentary rock composed mainly of grain size, sand-sized (0.0625 to 2 mm) silicate mineral, silicate grains, Cementation (geology), cemented together by another mineral. Sand ...
s. Dredged
basalt Basalt (; ) is an aphanite, aphanitic (fine-grained) extrusive igneous rock formed from the rapid cooling of low-viscosity lava rich in magnesium and iron (mafic lava) exposed at or very near the planetary surface, surface of a terrestrial ...
s from the top of the eastern and southeastern flanks of the seamount have been K–Ar dated 10.7 ± 0.5 and 16.3 ± 0.4 million years old, respectively. The oldest sample has been 40Ar/39Ar dated at 17 ± 0.3 million years old. Two small seamounts exist just southwest of Great Meteor and are encircled by the −3800 m bathymetric line. These are the Closs Seamount, roughly oriented NNE-SSW, with its peak at depth and covering an area of approximately , and the Little Meteor Seamount, located NNE of Closs, with over and a flat top below sea level. The
German German(s) may refer to: * Germany, the country of the Germans and German things **Germania (Roman era) * Germans, citizens of Germany, people of German ancestry, or native speakers of the German language ** For citizenship in Germany, see also Ge ...
research vessel A research vessel (RV or R/V) is a ship or boat designed, modified, or equipped to carry out research at sea. Research vessels carry out a number of roles. Some of these roles can be combined into a single vessel but others require a dedicated ...
''
Meteor A meteor, known colloquially as a shooting star, is a glowing streak of a small body (usually meteoroid) going through Earth's atmosphere, after being heated to incandescence by collisions with air molecules in the upper atmosphere, creating a ...
'' discovered the tablemount in 1938. It was given the name Great Meteor ''
Bank A bank is a financial institution that accepts Deposit account, deposits from the public and creates a demand deposit while simultaneously making loans. Lending activities can be directly performed by the bank or indirectly through capital m ...
'', a designation still used in the official GEBCO
gazetteer A gazetteer is a geographical dictionary or wikt:directory, directory used in conjunction with a map or atlas.Aurousseau, 61. It typically contains information concerning the geographical makeup, social statistics and physical features of a co ...
.


Formation

The
New England hotspot The New England hotspot, also referred to as the Great Meteor hotspot and sometimes the Monteregian hotspot, is a volcanic hotspot in the North Atlantic Ocean. It created the Monteregian Hills intrusions in Montreal and Montérégie, the White ...
formed the White Mountains 124 to 100 million years ago when the
North American continent North America is a continent in the Northern and Western hemispheres. North America is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South America and the Caribbean Sea, and to the sou ...
was directly overhead. As the continent drifted to the west, the hotspot gradually moved offshore. On a southeasterly course, the hotspot formed
Bear Seamount The Bear Seamount is a guyot or flat-topped underwater volcano in the Atlantic Ocean. It is the oldest of the New England Seamounts, which was active more than 100 million years ago. It was formed when the North American Plate moved over the New ...
, the oldest in the chain, about 100 to 103 million years ago. Over the course of millions of years, it continued creating the rest of the seamounts, eventually culminating in the Nashville Seamount about 83 million years ago. As the Atlantic Ocean continued to
spread Spread may refer to: Places * Spread, West Virginia Arts, entertainment, and media * ''Spread'' (film), a 2009 film. * ''$pread'', a quarterly magazine by and for sex workers * "Spread", a song by OutKast from their 2003 album ''Speakerboxxx/T ...
, the hotspot eventually traveled further east, forming the Great Meteor Seamount where it is found today.Revised August 25, 2010 by the Ocean Explorer
Radiometric dating Radiometric dating, radioactive dating or radioisotope dating is a technique which is used to Chronological dating, date materials such as Rock (geology), rocks or carbon, in which trace radioactive impurity, impurities were selectively incorporat ...
of
basalt Basalt (; ) is an aphanite, aphanitic (fine-grained) extrusive igneous rock formed from the rapid cooling of low-viscosity lava rich in magnesium and iron (mafic lava) exposed at or very near the planetary surface, surface of a terrestrial ...
from the Great Meteor Seamount has given ages of about 11 and 16 million years old, with the bulk of the seamount possibly having formed about 22 million years ago.


Ecology

The unique ecological condition of the Great Meteor Seamount is shown by the many endemic
copepod Copepods (; meaning 'oar-feet') are a group of small crustaceans found in nearly every freshwater and saltwater habitat (ecology), habitat. Some species are planktonic (living in the water column), some are benthos, benthic (living on the sedimen ...
and
nematode The nematodes ( or ; ; ), roundworms or eelworms constitute the phylum Nematoda. Species in the phylum inhabit a broad range of environments. Most species are free-living, feeding on microorganisms, but many are parasitic. Parasitic worms (h ...
species. SPOTLIGHT 5 ''Great Meteor Seamount''
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References

{{Authority control Guyots Seamounts of the Atlantic Ocean Hotspot volcanoes Miocene volcanoes Former islands from the last glacial maximum