Undersea Volcano Creates New Island Near Japan’s Iwo Jima, Longevity Uncertain

While volcanic activity near Iwo Jima, an island in the Pacific Ocean, has heightened, and similar undersea eruptions have occurred recently, the creation of a new island is a noteworthy occurrence, according to Usui.

An undersea volcano near Japan erupted three weeks ago, offering a unique glimpse of the formation of a small new island. However, experts suggest that the longevity of this new landmass might be limited.

The unnamed volcano, situated approximately 1km off the southern coast of Iwo Jima (referred to as Ioto in Japan), initiated its most recent series of eruptions on October 21. In 10 days, volcanic ash and rocks accumulated on the shallow seabed, forming an elevated tip above the sea surface. By early November, this accumulation transformed into a new island, measuring approximately 100 meters in diameter and reaching a height of about 20 meters above the sea, as per Yuji Usui, an analyst from the Japan Meteorological Agency’s volcanic division.

While volcanic activity near Iwo Jima, an island in the Pacific Ocean, has heightened, and similar undersea eruptions have occurred recently, the creation of a new island is a noteworthy occurrence, according to Usui. Subsequently, volcanic activity has diminished at the site, causing the newly formed island to slightly reduce in size due to its “crumbly” structure being susceptible to erosion by waves.

In the past, new islands have emerged from undersea volcanoes and seismic activities. In 2013, an eruption near Nishinoshima in the Pacific Ocean resulted in the formation of a growing island over a decade-long volcanic eruption. Another instance in 2013 saw a small island surfacing in Japan after a powerful 7.7-magnitude earthquake in Pakistan. In 2015, a new island emerged from the month-long eruption of a submarine volcano near Tonga.

Among the approximately 1,500 active volcanoes globally, Japan hosts 111, as it sits along the Pacific Ring of Fire, according to the Japan Meteorological Agency. Iwo Jima, known for intense World War II battles, holds historical significance, symbolizing the valor of U.S. Marines in the Pacific War.