Report on Home Reef (Tonga) — 1 January-7 January 2025
Smithsonian Institution / US Geological Survey
Weekly Volcanic Activity Report, 1 January-7 January 2025
Managing Editor: Sally Sennert.
Please cite this report as:
Global Volcanism Program, 2025. Report on Home Reef (Tonga) (Sennert, S, ed.). Weekly Volcanic Activity Report, 1 January-7 January 2025. Smithsonian Institution and US Geological Survey.
Home Reef
Tonga
18.992°S, 174.775°W; summit elev. -10 m
All times are local (unless otherwise noted)
The Tonga Geological Services reported that eruptive activity at Home Reef continued as of 2 January with lava expanding the N and NE shorelines. Satellite images showed emissions that were likely ash rich rising from the central vent on 17 December. Thermal anomalies were detected at least during 20-23 December. On 2 January small gas-and-ash puffs rose from the central vent at approximately one-minute intervals. The lava flow had grown to approximately 76,000 square meters and had a maximum dimension of 350 m (N-S) by 270 m (E-W). 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.