The new island, named Home Reef after its parent, is located in the Tonga-Kermadec subduction zone.
The Operational Land Imager-2 (OLI-2) camera, which is operating from NASA’s Landsat 9 satellite, has succeeded in capturing the birth of an island. The small piece of land emerged as a result of the eruption of an underwater volcano. This is the first time a satellite has succeeded in capturing the formation of a volcanic island.
The birth of a volcanic island
The submarine volcano named Home is part of the seabed extending from New Zealand to Tonga, a region known to have the highest density of submarine volcanoes on the planet. It was in this region that the Hunga Tonga-Hunga Ha’apai volcano erupted earlier this year.
NASA’s Landsat 9 satellite noticed the volcanic activity of the Home seamount. Starting on September 10, when the activity began and for several days, it was constantly oozing lava, expelling columns of steam and ash that the satellite was able to observe from high altitudes.
These types of eruptions usually spew large quantities of lava that then solidify in the water, creating volcanic islands. Many islands that have become nations today, such as Iceland, arose in this way thanks to a gigantic eruption of a submarine volcano. However, when it comes to smaller eruptions, islands often emerge and then disappear in a matter of time.
Landsat 9 was able to capture the birth of the newborn island in natural color images. The images also show the huge column of discolored water circulating near the island. Research suggests that such plumes, which are composed of acidic and superheated seawater, are made up of sulfur fragments and other volcanic rocks.
Subduction area with high volcanic activity
Subsequent investigations by the Tonga Geological Survey estimate that by September 14, the newly formed island area covered about 4,000 square meters and had an elevation of 10 meters above sea level. However, six days later, the island was already 24,000 square meters. The island is located southwest of Late Island, northeast of the Tonga submarine volcano, and northwest of Mo’unga’one.
“The volcano poses low risks to the aviation community and residents of Vava’u and Ha’apai,” the Tonga Geological Survey said. “However, all vessels are advised to navigate more than 4 kilometers away from Home Reef until further notice.” The service likewise reported that most of the ash should fall within a few kilometers of the underwater volcano.
The new island, named Home Reef after its parent, is located in the Tonga-Kermadec subduction zone. This area is characterized as the boundary where three tectonic plates converge, the Pacific Plate, which is the largest of them, is sinking under two other smaller plates. Thanks to this, the region is known for its great volcanic activity and also for being the region where large marine trenches are formed.
[Photos: NASA Earth Observatory/Lauren Dauphin]
Story originally published in Spanish in Ecoosfera