The explosive activity at the eruption site continues.
It seems that the origin hydrovolcanic activity, involving extraneous water, transited into the conventional, only magmatic explosions as they occur mainly on a new island surface. Vigorous vulcanian explosions continue to eject hot, juvenile, and plastic black-colored scoria fragments and form a new cinder cone by piling new ejecta. Dark black fine ash and white steam emissions accompany the activity.
The pumice raft continues to be observed floating towards the other side of the island, indicating a small amount of lighter pumice presented in the ash. This might represent a batch of fresh magma that drives explosions.
According to the Japan Meteorological Agency (JMA), the eruption site was affirmed at roughly the same location as happened in July-August, October and December last year. Over the past years, the volcanic activity at the volcano has caused the island to rise, actually some spots have risen more than 10 meters over the past ten years.
Ioto (硫黄島, also known as Iwo-jima) volcano is a triangular-shaped, flat, 8 km long and up to 4.5 wide volcanic island stretching NE-SW. It is surrounded by steep cliffs under the sea, which belong to a 9-km-wide submarine caldera. Parts of the caldera have been experiencing remarkably strong uplift (up to more than 1 meter per year and averaging 25 cm / year over several centuries). There is strong hydrothermal activity at present, at fumaroles along a NE-SW zone cutting through Moto-yama. Many phreatic eruptions occurred in historic times, mostly from vents on the west and NW sides of the island.
