'Ghost island' emerges after underwater volcanic eruption, then quickly vanishes; details inside

A series of satellite images shows the short lifespan of a “ghost island” that vanished pretty quickly in the Caspian Sea after emerging. It disappeared due to an underwater volcano that blew its top. According to NASA’s Earth Observatory, it was in January 2023 when the fleeting landmass emerged above Kumani Bank. It is an underwater volcano about 15 miles (24 kilometers) off the east coast of Azerbaijan. According to the Live Science website, by the time the volcano was fully formed, on February 4, 2023, the island measured around 1,300 feet (400 meters) across.

The emerged island was unstable, and it had “nearly eroded, retreating from view like an apparition" by the time the last photograph was clicked in December 2024, Earth Observatory representatives wrote. The island by now has likely disappeared. Following its discovery in 1861, Kumani Bank has erupted eight times, according to Live Science, and each outburst lasted only a few days. Despite a short period, these events led to at least some form of temporary island.

When did the strongest eruption occur

The strongest eruption was recorded in 1950, and it resulted in a 2,300-foot-wide (700 m) landmass that stood 20 feet (6 m) above sea level. Kumani Bank is a mud volcano, which means it erupts with a superheated mix of mud and water instead of lava and ash.

Azerbaijan has one of world’s highest concentrations of mud volcanoes

Azerbaijan has one of the world’s highest concentrations of mud volcanoes, with over 300 muddy vents on land and offshore. This is because the country sits on a “convergence zone” where the Arabian and Eurasian tectonic plates meet, causing increased geothermal activity.

Although mud volcanoes are not as violent or destructive as other volcanoes, they do contain high levels of pressurized natural gas. Sparks from colliding rocks can ignite this gas, causing occasional fiery outbursts. In 2021, an underwater mud volcano near Kumani Bank is believed to have triggered a massive fire, rising several hundred feet above the Caspian Sea.