RVO reported that an eruption began at Garbuna on the afternoon of 16 October when "white vapor" rose above the volcano and a couple of felt earthquakes occurred. On 17 October, an eruption column rose 3-4 km above the volcano's summit (or 11,700-15,000 ft a.s.l.). At 1100 fine ash fell on the W and NW sides of the volcano, covering two plantations. Water sources originating from Garbuna were affected by the eruption. According to RVO, the volcano last erupted about 1,700 years ago.

Geological Summary. The basaltic-to-dacitic Krummel-Garbuna-Welcker Volcanic Complex consists of three volcanic peaks located along a 7-km N-S line above a shield-like foundation at the southern end of the Willaumez Peninsula. The central and lower peaks of the centrally located Garbuna contain a large vegetation-free area that is probably the most extensive thermal field in Papua New Guinea. A prominent lava dome and blocky lava flow in the center of thermal area have resisted destruction by thermal activity, and may be of Holocene age. Krummel volcano at the south end of the group contains a summit crater, breached to the NW. The highest peak of the group is Welcker volcano, which has fed blocky lava flows that extend to the eastern coast of the peninsula. The last major eruption from both it and Garbuna volcanoes took place about 1800 years ago. The first historical eruption took place at Garbuna in October 2005.

Sources: Rabaul Volcano Observatory (RVO), Darwin Volcanic Ash Advisory Centre (VAAC), The National