Daikoku Sulfur Cauldron

Daikoku Sulphur Cauldron, Northern Marianas
Daikoku Sulphur Cauldron at the moment of discovery / screenshot from NOAA video / public domain.

Main characteristics

Coordinates: 21.3243 N 144.1938 E
No:566        (list of all attractions)
Category:Volcanoes, Lakes, Geothermal fields, Ecosystems, Animal colonies
Values:Geology, Biology
Address:Oceania, Micronesia, Northern Mariana Islands, Northern Island Municipality, some 155 km NNW from Farallon de Pajaros island, crater of Daikoku volcano (submarine) to the north from the summit, at the depth of some 420 m
Temperature of liquid:187° C

Earlier people thought that lakes of liquid sulfur are found only in outer space, not on Earth. Since the 2005 - 2006 some are known also on Earth - in deep seas. Most impressive of these sulfur lakes is Daikoku Sulfur Cauldron.


The remote area between Northern Mariana Islands and Bonin Islands has rather many active undersea volcanoes which provide much information about the geology of this subduction zone.

In 2004 was discovered one of these volcanoes, named Daikoku Seamount - a word given by Japanese fishermen for this fishing area. Its summit is 323 m below the surface of the sea.

In May 2006 the scientists on research vessel "Melville" (National Oceanic and Atmospheric Agency (NOAA)) with the help of a robot - submersible Remotely Operated Vehicle (ROV) "Jason" - noticed a weird, black spot in a crater north from the tallest summit of Daikoku volcano. As they dropped an anchor chain on the weird spot - it turned out that this is a "lake" of liquid sulfur covered with a black coating.

Several further scientific expeditions have researched this weird crater lake. NOAA mission "Submarine Ring of Fire 2014 - Ironman" in 2014 registered an ongoing eruption - rising plume from the summit (in 2006 there was only geothermal activity). There were registered also new craters.

Black coating over the liquid sulphur, Daikoku Seamount
Black coating over the liquid sulphur / Submarine Ring of Fire 2006 Expedition, NOAA Vents Program / public domain.

This lake is one of openings of Daikoku volcano and we do not know whether it will exist for long. At least in December 2016 there still were reported emanations of liquid sulfur (2).


Sulfur Cauldron is located at the depth of some 420 m and is some 4.5 by 3 m large - thus it is not exactly a "lake". The pool of sulfur is covered with black, elastic crust. The rising gases (carbon dioxide, hydrogen) are moving the crust - it is continuously billowing. These gases look similar to a smoke (but under the water!).

Fish which loves sulfur

Champagne vents of North West Eifuku Volcano, Northern Mariana
Flatfish Symphurus thermophilus, Daikoku Seamount / Submarine Ring of Fire 2006 Expedition, NOAA/PMEL / public domain.

Although this is nearly unique landmark on Earth, there exists life form which seems to enjoy living near them. This is flatfish Symphurus thermophilus which was described as a new species only in 2010. The largest of these fishes reach 11 cm of length.

This fish lives around the summits of several volcanoes in Pacific and, it seems, it needs to live in sulfur rich environment - which is toxic to most life forms on Earth! In Daikoku Sulfur Cauldron the fish simply lives ON the black crust of the sulfur lake. The crust is considerably cooler than the sulfur below it - but nevertheless this is quite hot place for life! Fish here lives in incredible density - in Daikoku have been counted 392 flatfishes per square meter! These weird creatures have developed ability to survive in extreme acidity (pH - up to 2.0), in high temperature and toxic environment rich with hydrogen sulphide. Although the fish feeds on shrimps, it is possible that they have developed ability to consume chemosynthetic bacteria.

Around the Sulfur Cauldron live also other organisms - tubeworms, crabs, snails.

Is this lake unique?

Earlier such lakes of liquid sulfur were reported on Io - moon of Jupiter. Thus one can think that Daikoku Seamount contains some kind of space oddity. Nevertheless there are known some other sulfur lakes on Earth.

On the nearby Nikko Seamount (Japan) a smaller sulfur lake was discovered some months earlier - in November 2005. It is possible though that in Nikko there are bigger lakes of molten sulphur than in Daikoku. There has been discovered also the evidence of older sulfur lakes in Macauley Cone (Kermadec Arc) (3).

Some have been registered also above the sea level: in 1989 there have been reported short lived lakes of molten sulfur in Poás volcano (Costa Rica).

Daikoku Sulfur Cauldron though is the most impressive lake of liquid sulfur known to us.


See Daikoku Sulfur Cauldron on the map of Northern Mariana Islands!

Landmarks of Northern Mariana Islands

Togari Natural Arch, North Marianas
Togari Natural Arch, Pagan / NOAA Photo Library, / CC BY 2.0

Highlights of Northern Mariana Islands are:

  • Unique submarine volcanoes - research of the submarine volcanoes north from Farallon de Pajaros has revealed several phenomena very rare or unique on Earth.
  • Beautiful, rugged nature of the Northern Islands. These small islands are tops of steep, active volcanos and are covered with pristine tropical vegetation.
  • Latte stone settings - unique megalithic structures, found only in Mariana Islands. The largest megaliths are found in Tinian and Rota islands.
  • Petroglyphs. In several caves in Rota, Saipan and Tinian are found interesting, prehistoric drawings.


Mount Shishaldin at sunset, Alaska
Mount Shishaldin at sunset /Erik Beach, 2007, / public domain

Over the last 10,000 years in some 1,500 places around the Earth through the crust of the planet has been emitted lava, ash and gases from the mantle of Earth. Each of these places could be considered to be an active volcano and each of these 1,500 active volcanoes and also some of the inactive ones are such unusual places. But, as always in life, some are more unusual than others.


Pingualuit crater, Canada
Pingualuit crater. / NASA, Wikimedia Commons, public domain

There are many factors which can make lakes, sea bays or rivers unusual. There are unusual crater lakes - some contain pure acid. There exist lakes of lava and there are boiling lakes. Unusual are the lakes in giant sinkholes - some of them have covered themselves with stone lids and are isolated from the outside world.


  1. Bob Embley. Discovery of the Sulfur Cauldron at Daikoku Volcano: A Window into an Active Volcano. NOAA website, accessed in May 6, 2017.
  2. Thom Hoffman. Daikoku Dive 2: Sulphur So Good. Schmidt Ocean Institute website, accessed in May 6, 2017.
  3. C. E. J. de Ronde, W. W. ChadwickJr, R. G. Ditchburn, R. W. Embley, V. Tunnicliffe, E. T. Baker, S. L. Walker, V. L. Ferrini, S. M. Merle. Molten Sulfur Lakes of Intraoceanic Arc Volcanoes. Advances in Volcanology, pp 261 - 288.

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