Ulawun Decade Volcano, Papua New Guinea

The least known of the Decade Volcanoes

volcano number: 0502-12= (according to Volcanoes of the World, 1994 edition)

summit elevation: 2334 m

location: 5.05°S, 151.33°E

Last changed on 6 April 1996

Location map of New Britain Island with Ulawun volcano.

Ulawun in January 1967, shortly before or after a small explosive eruption. View is from Ulamona Mission (11 km to the NW). The NW valley is distinctly visible in the central upper part of the volcano. A major fault scarp looms above the western lower slope of the cone (right margin of photo). The photo was taken from Johnson et al. (1972).

Ulawun, situated on the island of New Britain is one of the most active volcanoes of Papua New Guinea and displays a wide variety of eruptive styles. This is why Ulawun was chosen one of fifteen Decade Volcanoes. Due to the 1994-present Rabaul eruption and its effects, little work has been carried out in the framework of the Decade Volcano Project, and no information is available on the WWW about this volcano.

Table 1: Eruptions of Ulawun volcano, Papua New Guinea

• 11 March 1700
• 1878
• 1898
• April 1915: vigorous eruption with possible pyroclastic flows, some damage in native villages
• 21 (?) July 1918: "smoke" forms a black plume
• 28 (?) May 1919: large columns of "dark smoke"
• July - 17 September (or later) 1927: small ash emissions
• May 1937: unconfirmed reports about a small eruption
• 26 January 1941: brief eruption (one single strong explosion)
• 1951: explosion heard from "within Ulawun" and earth shock, but no confirmed eruption
• Between December 1957 and March 1958, there was a brief eruption causing ash fall at Ulamona Mission
• late July 1960 until November 1962: explosive eruption, no pyroclastic flows recorded
• 17 March - early May 1963: moderate size explosive eruption
• 22 January - 28 December 1967: moderate size explosive eruption, slight damage
• 15 January - 11 February 1970: vigorous explosive-effusive eruption with pyroclastic flows (8 x 10^6 m^3 of lava)
• 4-19 October 1973: vigorous explosive-effusive eruption with pyroclastic flows (10^7 m^3 of lava)
• 7-14 May 1978: spectacular explosive-effusive eruption with pyroclastic flows from the summit and lava flows from a fissure on the lower E flank (upper end of fissure at 560 m elevation)
• 6-7 October 1980: powerful explosive eruption with major pyroclastic flows from summit crater
• 6 November 1983 - 13 March 1984: small-scale phreatomagmatic eruption
• 23 August - 11 September 1984: minor phreatomagmatic eruption
• 30 December 1984 - 27 January 1985: small-scale magmatic eruption producing a small volume (10^5 m^3) of lava within the summit crater
• 17-22 November 1985: vigorous explosive-effusive eruption with pyroclastic flows
• 1 January - December 1989: small-scale phreatomagmatic eruption
• 12-31 January 1993: small-scale explosive eruption, possible lava effusion on crater floor
• June 1994: glow at summit, possible minor eruptive activity

22 confirmed eruptions and two possible eruptions are known from Ulawun through 1993 (table 1), the last major event occurred in November 1985 when voluminous pyroclastic flows and lava flows were erupted. Similar eruptions had occurred earlier in 1980, 1978 (involving a spectacular flank eruption), 1973 and 1970.

Vigorous ash emission from two vents within the summit crater and lava emission (arrow) and pyroclastic avalanching from a SE flank fissure during the initial stage of the May 1978 eruption (9 May 1978, at 1045). This photo is from McKee et al. (1981).

Eruption of Ulawun on 20 November 1985, at the climax of the 1985 eruption, seen from Ulamona Mission. Successiv pyroclastic flows spill down the NW valley of the volcano. Taken from Bulletin of Volcanic Eruptions No. 25 (for 1985).

References about Ulawun volcano

Cooke RJS (1981) Notes on the activity of Ulawun volcano, 1700-1958: results of a literature search. In: Johnson RW (ed) Cooke-Ravian volume of volcanological papers. Geological Survey of Papua New Guinea Memoir 10: 147-151

Cooke RJS, McKee CO, Dent VF and Wallace DA (1976) Striking sequence of volcanic eruptions in the Bismarck volcanic arc, Papua New Guinea, in 1972-1975. In: Johnson RW (ed) Volcanism in Australasia. Elsevier Amsterdam: 149-172

Johnson RW, Davies RA and White AJR (1972) Ulawun volcano, New Britain. Bulletin of the Australian Bureau of Mineral Resources 142:

McKee CO, Almond RA, Cooke RJS and Talai B (1981) Basaltic pyroclastic avalanches and flank effusion from Ulawun volcano in 1978. In: Johnson RW (ed) Cooke-Ravian volume of volcanological papers. Geological Survey of Papua New Guinea Memoir 10: 153-165

McKee CO and Mori J (1987) Ulawun. Bulletin of Volcanic Eruptions for 1985: 17-19