Report on Home Reef (Tonga) — 11 October-17 October 2023
Smithsonian Institution / US Geological Survey
Weekly Volcanic Activity Report, 11 October-17 October 2023
Managing Editor: Sally Sennert.
Please cite this report as:
Global Volcanism Program, 2023. Report on Home Reef (Tonga) (Sennert, S, ed.). Weekly Volcanic Activity Report, 11 October-17 October 2023. 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 Home Reef was erupting with a total of 11 eruptive events detected in satellite data during 12-17 October. On 14 October the Aviation Color Code was Yellow and the Hazard Alert was Orange; on 17 October the Aviation Color Code was lowered to Green and the Hazard Alert was lowered to Yellow, though mariners continued to be advised to stay 4 km away from the island. According to the Wellington VAAC a pilot observed an ash plume below 300 m (1,000 ft) a.s.l. in the vicinity of the volcano on 17 October, though the Tonga Meteorological Services stated that the emissions were mainly composed of steam. The most recent dimensions of the island were estimated to be about 424 m N-S and 223 m E-W, with an approximate total surface area of 17 acres, based on a 10 October satellite image. The island had steep headlands on the E half and a more gradual slope on the W half.
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.
Sources: Tonga Geological Services, Government of Tonga, Wellington Volcanic Ash Advisory Center (VAAC)