CVGHM reported incandescence at Dukono's summit during 31 March-24 April. On 25 April, incandescent material was ejected 25 m above the summit. During 30 April-2 May seismicty increased. On 25 May, an ash plume rose to an altitude of 1.4-2.1 km (4,600-6,900 ft) a.s.l. and was accompanied by thunderous and booming sounds. On 29 May, an ash plume rose to an altitude of 2.3 km (7,500 ft) a.s.l. and again was accompanied by thunderous and booming sounds. The Alert Level was raised to 3 (on a scale of 1-4). Residents and visitors were not permitted within 3 km of the summit.

Geological Summary. The Dukono complex in northern Halmahera is on an edifice with a broad, low profile containing multiple peaks and overlapping craters. Almost continuous explosive eruptions, sometimes accompanied by lava flows, have occurred since 1933. During a major eruption in 1550 CE, a lava flow filled in the strait between Halmahera and the Gunung Mamuya cone, 10 km NE. Malupang Wariang, 1 km SW of the summit crater complex, contains a 700 x 570 m crater that has also had reported eruptions.

Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)