Loki's Castle (hydrothermal field)
Encyclopedia
Hydrothermal vent
A hydrothermal vent is a fissure in a planet's surface from which geothermally heated water issues. Hydrothermal vents are commonly found near volcanically active places, areas where tectonic plates are moving apart, ocean basins, and hotspots. Hydrothermal vents exist because the earth is both...
s in the mid-Atlantic ocean, located at 73 degrees north
73rd parallel north
The 73rd parallel north is a circle of latitude that is 73 degrees north of the Earth's equatorial plane, in the Arctic. It crosses the Atlantic Ocean, Europe, Asia, the Arctic Ocean and North America....
on the Mid-Atlantic Ridge
Mid-Atlantic Ridge
The Mid-Atlantic Ridge is a mid-ocean ridge, a divergent tectonic plate boundary located along the floor of the Atlantic Ocean, and part of the longest mountain range in the world. It separates the Eurasian Plate and North American Plate in the North Atlantic, and the African Plate from the South...
between Greenland
Greenland
Greenland is an autonomous country within the Kingdom of Denmark, located between the Arctic and Atlantic Oceans, east of the Canadian Arctic Archipelago. Though physiographically a part of the continent of North America, Greenland has been politically and culturally associated with Europe for...
and Norway
Norway
Norway , officially the Kingdom of Norway, is a Nordic unitary constitutional monarchy whose territory comprises the western portion of the Scandinavian Peninsula, Jan Mayen, and the Arctic archipelago of Svalbard and Bouvet Island. Norway has a total area of and a population of about 4.9 million...
at a depth of 2352 metres (7,716.5 ft). They were discovered in mid-July 2008 and are the most northerly black smokers which have been located. They are of geological interest as they are in a more stable area of the Earth's crust, where tectonic forces are less and consequently fields of hydrothermal vents are relatively less common.
Discovery
The vents were discovered by a 25-person multinational scientific expedition of the University of BergenUniversity of Bergen
The University of Bergen is located in Bergen, Norway. Although founded as late as 1946, academic activity had taken place at Bergen Museum as far back as 1825. The university today serves more than 14,500 students...
, Norway, more than 120 nautical miles (222.2 km) north of what were previously the most northern vents which were discovered in 2005. The 2005 and 2008 expeditions were both led by geologist Rolf Pedersen of the university’s Centre for Geobiology, aboard the new Research Vessel G.O. Sars (named after the Norwegian marine biologist Georg Ossian Sars and launched in May 2003). The vents were located using a remotely controlled undersea vehicle.
Activity
The five active chimneys of Loki's Castle are venting water as hot as 300 °CCelsius
Celsius is a scale and unit of measurement for temperature. It is named after the Swedish astronomer Anders Celsius , who developed a similar temperature scale two years before his death...
(570 °F
Fahrenheit
Fahrenheit is the temperature scale proposed in 1724 by, and named after, the German physicist Daniel Gabriel Fahrenheit . Within this scale, the freezing of water into ice is defined at 32 degrees, while the boiling point of water is defined to be 212 degrees...
) and sit on a vast mound of sulfide
Sulfide
A sulfide is an anion of sulfur in its lowest oxidation state of 2-. Sulfide is also a slightly archaic term for thioethers, a common type of organosulfur compound that are well known for their bad odors.- Properties :...
minerals which is about 825 ft (250 m) in diameter at its base, and some 300 feet (90 m) across its top. A member of the 2008 Expedition, oceanographer Marvin Lilley of the University of Washington
University of Washington
University of Washington is a public research university, founded in 1861 in Seattle, Washington, United States. The UW is the largest university in the Northwest and the oldest public university on the West Coast. The university has three campuses, with its largest campus in the University...
, has speculated that this may be the largest such deposit ever seen on the sea floor. The active chimneys are mostly black in colour, but are covered with mats of white bacteria which are living on minerals and materials emitted by the vents. The older chimneys are a mottled red colour, due to the presence of deposits of oxidised iron.
Preliminary observations have shown the warm area around the Loki's Castle vents to be alive with diverse and apparently unique microorganism
Microorganism
A microorganism or microbe is a microscopic organism that comprises either a single cell , cell clusters, or no cell at all...
s and vent fauna, unlike vent communities observed elsewhere.
The vent field was given the name Loki's Castle as its shape reminded its discoverers of a fantasy castle. The reference to the ancient Norse god Loki
Loki
In Norse mythology, Loki or Loke is a god or jötunn . Loki is the son of Fárbauti and Laufey, and the brother of Helblindi and Býleistr. By the jötunn Angrboða, Loki is the father of Hel, the wolf Fenrir, and the world serpent Jörmungandr. By his wife Sigyn, Loki is the father of Nari or Narfi...
was explained by a University of Bergen press release that said it "was an appropriate name for a field that was so difficult to locate".
External links
- Sandra Hines, Scientists break record by finding northernmost hydrothermal vent field, University of Washington Press Release, 24 July 2008.
- 2008 University of Bergen Expedition Journal for Day 17 (15 July 2008), describing the moment of discovery.
- Photographs of the 2008 University of Bergen Expedition team members
- Background information about hydrothermal fields (provided by the Centre for Geobiology, University of Bergen)
- Loki's Castle, InterRidge Vents Database
73.55°N 8.15°E