Loki's Castle is a field of five active

hydrothermal vent A hydrothermal vent is a fissure on the seabed from which geothermally heated water discharges. They are commonly found near volcanically active places, areas where tectonic plates are moving apart at mid-ocean ridges, ocean basins, and hotspo ...

s in the mid-Atlantic Ocean, located at 73 degrees north on the

Mid-Atlantic Ridge The Mid-Atlantic Ridge is a mid-ocean ridge (a divergent or constructive plate boundary) located along the floor of the Atlantic Ocean, and part of the longest mountain range in the world. In the North Atlantic, the ridge separates the North A ...

between

Greenland Greenland ( kl, Kalaallit Nunaat, ; da, Grønland, ) is an island country in North America that is part of the Kingdom of Denmark. It is located between the Arctic and Atlantic oceans, east of the Canadian Arctic Archipelago. Greenland ...

and

Norway Norway, officially the Kingdom of Norway, is a Nordic countries, Nordic country in Northern Europe, the mainland territory of which comprises the western and northernmost portion of the Scandinavian Peninsula. The remote Arctic island of ...

at a depth of . The vents were discovered in mid-July 2008 and are the most northerly

black smoker A hydrothermal vent is a fissure on the seabed from which geothermally heated water discharges. They are commonly found near volcanically active places, areas where tectonic plates are moving apart at mid-ocean ridges, ocean basins, and hotspot ...

s to date. They are of geological interest as they occur in a relatively stable region of the Earth's crust, one with diminished tectonic forces and consequently fewer hydrothermal vents.

Discovery

The vents were discovered by a 25-person multinational scientific expedition of the

University of Bergen The University of Bergen ( no, Universitetet i Bergen, ) is a research-intensive state university located in Bergen, Norway. As of 2019, the university has over 4,000 employees and 18,000 students. It was established by an act of parliament in 194 ...

, Norway, more than north of what were previously the northernmost known, discovered in 2005. The 2005 and 2008 expeditions were both led by geologist Rolf Pedersen of the university's Centre for Geobiology, aboard the research vessel ''G.O. Sars'' (named after the Norwegian marine biologist

Georg Ossian Sars Prof Georg Ossian Sars HFRSE (20 April 1837 – 9 April 1927) was a Norwegian marine and freshwater biologist. Life Georg Ossian Sars was born on 20 April 1837 in Kinn, Norway (now part of Flora), the son of Pastor Michael Sars and Maren ...

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

°C The degree Celsius is the unit of temperature on the Celsius scale (originally known as the centigrade scale outside Sweden), one of two temperature scales used in the International System of Units (SI), the other being the Kelvin scale. The d ...

(570 °F) and sit on a vast mound of

sulfide Sulfide (British English also sulphide) is an inorganic anion of sulfur with the chemical formula S2− or a compound containing one or more S2− ions. Solutions of sulfide salts are corrosive. ''Sulfide'' also refers to chemical compounds la ...

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 Oceanography (), also known as oceanology and ocean science, is the scientific study of the oceans. It is an Earth science, which covers a wide range of topics, including ecosystem dynamics; ocean currents, waves, and geophysical fluid dynamic ...

Marvin Lilley 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 A microorganism, or microbe,, ''mikros'', "small") and ''organism'' from the el, ὀργανισμός, ''organismós'', "organism"). It is usually written as a single word but is sometimes hyphenated (''micro-organism''), especially in old ...

s and vent fauna, unlike vent communities observed elsewhere. One of these is the archaeal phylum

Lokiarchaeota Lokiarchaeota is a proposed phylum of the Archaea. The phylum includes all members of the group previously named Deep Sea Archaeal Group (DSAG), also known as Marine Benthic Group B (MBG-B). Lokiarchaeota is part of the superphylum Asgard contai ...

, which is named after Loki's Castle. The vent field was given the name Loki's Castle as its shape reminded its discoverers of a fantasy castle. The reference is to the ancient Norse god of trickery,

Loki Loki is a god in Norse mythology. According to some sources, Loki is the son of Fárbauti (a jötunn) and Laufey (mentioned as a goddess), and the brother of Helblindi and Býleistr. Loki is married to Sigyn and they have two sons, Narfi ...

. It was felt to be "an appropriate name for a field that was so difficult to locate".

References

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 membersBackground information about hydrothermal fields
(provided by the Centre for Geobiology, University of Bergen)
Loki's Castle
InterRidge Vents Database {{coord, 73.55, N, 8.15, E, display=inline,title Hydrothermal vents Volcanoes of the Atlantic Ocean

Discovery

Activity

See also

References

External links