A once-hidden Japanese volcano has been rising up out of the Pacific ocean. Thanks to new research published last month in the journal Geology, scientists now have a better understanding of how this very young island formed.
Nishinoshima is a volcanic island about 620 miles south of Tokyo, which was first seen erupting in 1973. According to IFLScience, it’s part of a much larger underwater volcano that reaches nearly two miles high and 58 miles in circumference at its base.
In November 2013, explosive volcanic activity was reported near the island of Nishinoshima. Within a month, enough lava had flowed up to the ocean surface to create a new island 82 feet above sea level. And by the end of the year, this new island merged with Nishinoshima to create an even larger island.
After observing the island’s birth, the authors of this new study have revealed that its formation occurred in two main stages. The first involved the sudden release of hot, broiling lava into the shallow, cold water. An envelope of steam rapidly formed along the margins of the lava, before explosively expanding into the water and dramatically propelling glassy molten blobs high into the air.
This is known as a “Surtseyan” eruption, named after the Icelandic island that formed in precisely the same way back in 1963. Within three days of discovering the island, the Japanese Maritime Self-Defense Force noticed that the eruption style changed.
The island was now breaching the surface, and water could no longer fall into the lava-filled vent. “Dry” slugs of gas were now suddenly bursting up from the miniature mountain. This “Strombolian” eruption phase produced spectacular fire fountains, and allowed the lava to build up on the pre-existing rock.
Instead of taking a direct path from the vent of the volcano down into the sea, the lava took a far stranger route. As older lava cooled, it formed peculiar twists, bumps, tubes and grooves at the surface, so newer lava was forced down these natural helter-skelters before reaching the water and cooling.
The newly formed island is still volcanically active and continues to create new land. “In fact, since the eruption began, about 80 Olympic-sized swimming pools’ worth of lava has been produced every single day,” IFLScience said.
And scientists are excited to see what life forms emerge from this “evolutionary experiment,” as volcanic land is extremely hospitable to life.
Watch Earthspace101’s video of the evolution of this new island:
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