By Sara E. Pratt, NASA Earth Observatory May 24, 2022
May 14, 2022. A plume of discolored water emitted by the Kavachi volcano.
Kavachi Volcano in the Solomon Islands of the Southwest Pacific, where hammerhead sharks roam, has entered an active phase of eruption.
The Kavachi Volcano in the Solomon Islands is one of the most active underwater volcanoes in the Pacific Ocean. According to the Smithsonian’s Global Volcanism Program, the volcano erupted in October 2021. Satellite data now show discolored water around Kavachi for several days in April and May 2022. .
The image above, acquired on May 14, 2022 by Operational Land Imager-2 (OLI-2) on Landsat 9, shows a plume of discolored water emanating from the underwater volcano, which is about 24 kilometers (15 miles) south. from Vangunu Island (shown below).
May 14, 2022. Kavachi Volcano, located about 15 miles south of Vangunu Island, emitted a plume of discolored water.
Previous research has shown that these plumes of overheated, acidic water often contain particles in part, fragments of volcanic rock, and sulfur. A 2015 scientific expedition to the volcano found two species of sharks, including hammers, that lived in the submerged crater. Researchers also found microbial communities that thrive on sulfur.
The presence of sharks in the crater raised “new doubts about the ecology of active underwater volcanoes and the extreme environments in which large marine animals may exist,” the scientists wrote in a 2016 Oceanography article, “Exploring the Sharkcano.” ‘”.
Prior to this recent activity, large eruptions were observed in Kavachi in 2014 and 2007. The volcano erupts almost continuously, and residents of nearby inhabited islands often report visible steam and ash. The island is named after a sea god from the villages of Gatokae and Vangunu, and is sometimes called Rejo te Kvachi, or “Kavachi Oven”.
Since its first eruption in 1939, Kavachi has created ephemeral islands on several occasions. But the islands, up to a kilometer long, have been eroded and ravaged by the action of the waves. It is currently estimated that the top of the volcano is 20 meters (65 feet) below sea level; its base is on the seabed at a depth of 1.2 kilometers (0.75 miles).
Kavachi formed in a tectonically active area: a subduction zone is located 30 kilometers (18 miles) southwest. The volcano produces lava ranging from basalts, rich in magnesium and iron, to andesitic, which contains more silica. It is known to have phreatomagmatic eruptions in which the interaction of magma and water causes explosive eruptions that expel steam, ash, fragments of volcanic rock and incandescent bombs.
Images from NASA’s Joshua Stevens Earth Observatory, using data from the United States Geological Survey’s Landsat.