On 7 February the Tonga Geological Services reported that analysis of satellite images showed no size changes, and no new lava flows at Home Reef. Thermal activity declined, with the last thermal anomaly identified on 25 January. That same day a series of plumes rose from the vent that were ash-rich near the base and mostly comprised of gas and steam at higher levels. Discolored water to the SW was visible. A new explosive vent, about 20 m in diameter, was located slightly W of the vent that produced lava flows. Ash deposits surrounded the vent and extended W and NW to the shoreline. Discolored water in the vicinity of the island was identified in a satellite image from 1 February. The Maritime Alert Level remained at Orange (the third level on a four-level scale), and mariners were advised to stay at least 2 nautical miles (3.7 km) away from the island. The Aviation Color Code remained at Yellow (the second level on a four-level scale), and the Alert Level for residents of Vava’u and Ha’apai remained at Green (the first level on a four-level scale).

Geological Summary. Home Reef, a submarine volcano midway between Metis Shoal and Late Island in the central Tonga islands, was first reported active in the mid-19th century, when an ephemeral island formed. An eruption in 1984 produced a 12-km-high eruption plume, large amounts of floating pumice, and an ephemeral 500 x 1,500 m island, with cliffs 30-50 m high that enclosed a water-filled crater. In 2006 an island-forming eruption produced widespread dacitic pumice rafts that drifted as far as Australia. Another island was built during a September-October 2022 eruption.

Source: Tonga Geological Services, Government of Tonga