Banua Wuhu submarine volcano

Submarine volcano

Submarine volcanoes are underwater fissures in the Earth's surface from which magma can erupt. They are estimated to account for 75% of annual magma output. The vast majority are located near areas of tectonic plate movement, known as ocean ridges...

 rises more than 400 m from the sea floor in the Sangihe Islands

Sangihe Islands

The Sangihe Islands – – are a group of islands constitute 2 regencies in northern Indonesia, the Sangihe Islands Regency & Sitaro Islands Regency...

 of Indonesia

Indonesia

Indonesia , officially the Republic of Indonesia , is a country in Southeast Asia and Oceania. Indonesia is an archipelago comprising approximately 13,000 islands. It has 33 provinces with over 238 million people, and is the world's fourth most populous country. Indonesia is a republic, with an...

. Historical records show that several ephemeral

Ephemeral

Ephemeral things are transitory, existing only briefly. Typically the term is used to describe objects found in nature, although it can describe a wide range of things....

 islands were formed and disappeared. A 90 m high island was formed in 1835, but then dwindled to only a few rocks in 1848. A new island was reportedly formed in 1889 and it was 50 m high in 1894. Another new island

New islands

New islands are islands which have been created recently, whether by means of vulcanism, erosion, glacial retreat, or other mechanisms. One of the most famous new volcanic islands is the small island of Surtsey, located in the Atlantic Ocean south of Iceland. It first emerged from the ocean...

was formed in 1919 but then disappeared by 1935.