is a

volcanic A volcano is a rupture in the crust of a planetary-mass object, such as Earth, that allows hot lava, volcanic ash, and gases to escape from a magma chamber below the surface. On Earth, volcanoes are most often found where tectonic plates a ...

deserted island A desert island, deserted island, or uninhabited island, is an island, islet or atoll that is not permanently populated by humans. Uninhabited islands are often depicted in films or stories about shipwrecked people, and are also used as stereoty ...

located in the Philippine Sea approximately off the coast of

Aogashima is a volcanic island to the south of Japan in northernmost Micronesia. It is the southernmost and most isolated inhabited island of the Izus, which are politically and administratively part of Japan but geographically not part of the Japanes ...

, near the southern end of the Izu archipelago, Japan.

Geography

The island is a

basalt Basalt (; ) is an 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 surface of a rocky planet or moon. More than 90 ...

and

olivine The mineral olivine () is a magnesium iron silicate with the chemical formula . It is a type of nesosilicate or orthosilicate. The primary component of the Earth's upper mantle, it is a common mineral in Earth's subsurface, but weathers quickl ...

pillar A column or pillar in architecture and structural engineering is a structural element that transmits, through compression, the weight of the structure above to other structural elements below. In other words, a column is a compression member. ...

with sheer sides, the only visible portion of an active submarine

volcanic caldera A caldera ( ) is a large cauldron-like hollow that forms shortly after the emptying of a magma chamber in a volcano eruption. When large volumes of magma are erupted over a short time, structural support for the rock above the magma chamber is ...

extending south of the island with a circumference of approximately . The above sea-level portion has a height of . The island is estimated to have been created by a volcanic

eruption Several types of volcanic eruptions—during which lava, tephra (ash, lapilli, volcanic bombs and volcanic blocks), and assorted gases are expelled from a volcanic vent or fissure—have been distinguished by volcanologists. These are often ...

around 20,000 years ago. In the immediate vicinity are numerous exposed and awash rocks. Due to its shape and heavy seas it is difficult to disembark on the island, although at times fishermen are known to have landed. The abundance of fish in the surrounding waters have made it attractive for both sport and commercial fishing.

History

The island has been known by Japanese fishermen and mariners from an early time. In 1870, a submarine eruption was recorded NNE of the island, resulting in the formation of a new islet, named , with a height of . The islet has subsequently sunk beneath sea level due to erosion. From 1974 to 1977, a series of underwater eruptions have been recorded, discoloring water in the area. In November 1991, a fishing vessel reported that a large section of the island's northern face had collapsed, resulting in a significant change in its profile. Further changes to the island's profile were recorded after 1992 earthquakes. Sumisu-tō is administratively part of

Tokyo Metropolis Tokyo (; ja, 東京, , ), officially the Tokyo Metropolis ( ja, 東京都, label=none, ), is the capital and largest city of Japan. Formerly known as Edo, its metropolitan area () is the most populous in the world, with an estimated 37.468 ...

References

External links

Japan Coast Guard submarine volcano database
* Izu Islands Uninhabited islands of Japan Extinct volcanoes of Asia Stacks of Japan Islands of Tokyo {{tokyo-geo-stub

Geography

History

See also

References

External links