By
14th May 2022. A plume of discolored water emitted from the Kavachi volcano.
The Kavachi volcano in the Solomon Islands in 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 Global Volcanism Program, the volcano entered an eruptive phase in October 2021. Now, satellite data shows discolored water around Kavachi for several days in April and May 2022.
The image above, acquired on May 14, 2022 by the Operational Land Imager-2 (OLI-2) on Landsat 9, shows a plume of discolored water emitted by the submarine volcano, which sits about 24 kilometers (15 miles) south of Vangunu Island (shown below).
May 14, 2022. The Kavachi volcano, located about 15 miles south of Vangunu Island, emitted a plume of discolored water.
Previous research has shown that such superheated sour water plumes typically contain particulates, volcanic rock fragments, and sulfur. A 2015 scientific expedition to the volcano found two species of sharks, including hammers, living in the submerged crater. Researchers have also discovered microbial communities that thrive on sulfur.
The sharks’ presence in the crater has raised “new questions about the ecology of active submarine volcanoes and the extreme environments in which large marine animals can exist,” the scientists wrote in a 2016 paper. Oceanography article, “Exploring the ‘Sharkcano’.”
Prior to this recent activity, large eruptions were observed at 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 of the Gatokae and Vangunu peoples, and it is sometimes also called Rejo te Kvachi, or “Kavachi’s oven”.
Since its first recorded eruption in 1939, Kavachi has repeatedly created ephemeral islands. But the islands, up to a kilometer long, have been eroded and washed away by wave action. The summit of the volcano is currently estimated to be 20 meters (65 ft) below sea level; its base rests on the seabed at a depth of 1.2 kilometers (0.75 miles).
Kavachi formed in a tectonically active zone – a subduction zone lies 30 kilometers (18 miles) to the southwest. The volcano produces lava ranging from basaltic, 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 eject steam, ash, fragments of volcanic rock, and glowing bombs.