Minor ash plumes had continued to be intermittently reported from this long-active volcano during October 2008-January 2009 (BGVN 33:11). The Darwin VAAC has provided continuous monitoring of the activity through satellite surveillance (table 10).

Table 10. Ash plumes reported from Dukono between 7 January 2009 and 30 May 2010 (UTC). Data from the Darwin Volcanic Ash Advisory Centre.

Dukono's visible plume was almost continuous between January 2009 and February 2010 with only two short periods of quiescence for about eight weeks between mid-February and mid-April 2009 and eight weeks from 11 December 2009 to 5 February 2010. Three periods of relatively stronger activity occurred in late April through 28 May 2009 and created ash plumes that drifted the greatest distances, 110-150 km. A higher level of activity occurred again in early to mid-August and in early December 2009 just before the second period of reduced activity. Two recent MODVOLC thermal alerts occurred on 30 May 2010; they were detected on both the Terra and Aqua satellites.

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.

Information Contacts: Darwin Volcanic Ash Advisory Centre (VAAC), Bureau of Meteorology, Northern Territory Regional Office, PO Box 40050, Casuarina, NT 0811, Australia (URL: http://www.bom.gov.au/info/vaac/); Center of Volcanology and Geological Hazard Mitigation (CVGHM), Jalan Diponegoro 57, Bandung 40122, Indonesia (URL: http://vsi.esdm.go.id/); Hawai'i Institute of Geophysics and Planetology (HIGP) Thermal Alerts System, School of Ocean and Earth Science and Technology (SOEST), University of Hawai'i, 2525 Correa Road, Honolulu, HI 96822, USA (URL: http://modis.higp.hawaii.edu/).