Report on Home Reef (Tonga) — 5 October-11 October 2022
Smithsonian Institution / US Geological Survey
Weekly Volcanic Activity Report, 5 October-11 October 2022
Managing Editor: Sally Sennert.
Please cite this report as:
Global Volcanism Program, 2022. Report on Home Reef (Tonga) (Sennert, S, ed.). Weekly Volcanic Activity Report, 5 October-11 October 2022. Smithsonian Institution and US Geological Survey.
18.992°S, 174.775°W; summit elev. -10 m
All times are local (unless otherwise noted)
The Tonga Geological Services reported that daily steam plumes from Home Reef were identified in satellite images during 4-11 October. The Aviation Color Code was raised to Orange (the second highest level on a four-color scale) on 5 October. At 0040 on 6 October an ash plume rose as high as 3 km (10,000 ft) a.s.l. and drifted 5 km SE. Satellite-based measurements showed that the island had not changed in size between 28 September and 10 October, remaining at 268 m N-S and 283 m E-W. The island reached 15-18 m above the water surface, and was steeper on the E half but more gently sloped on the W. The daily emission count variable with about 8-19 events per day during 4-9 October and about 1-3 per day during 10-11 October. The Aviation Color Code was lowered to Yellow on 11 October. Mariners were advised to stay 4 km away from the volcano.
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.