Report on Ulawun (Papua New Guinea) — September 1980
Scientific Event Alert Network Bulletin, vol. 5, no. 9 (September 1980)
Managing Editor: David Squires.
Ulawun (Papua New Guinea) Ash billows to 6 kilometers above crater
Please cite this report as:
Global Volcanism Program, 1980. Report on Ulawun (Papua New Guinea). In: Squires, D (ed.), Scientific Event Alert Network Bulletin, 5:9. Smithsonian Institution. http://dx.doi.org/10.5479/si.GVP.SEAN198009-252120.
Papua New Guinea
5.05°S, 151.33°E; summit elev. 2334 m
All times are local (unless otherwise noted)
Australian radio reports that Ulawun began to erupt during the night of 6-7 October. Pilots saw ash "billowing" to about 6 km above the crater during the morning of the 7th. A police spokesman said ash was thought to be falling more than 30 km from the volcano. Police were considering the evacuation of Ulamona Catholic mission, the settlement closest to the volcano.
Geologic Background. The symmetrical basaltic-to-andesitic Ulawun stratovolcano is the highest volcano of the Bismarck arc, and one of Papua New Guinea's most frequently active. Ulawun volcano, also known as the Father, rises above the north coast of the island of New Britain across a low saddle NE of Bamus volcano, the South Son. The upper 1000 m of the 2334-m-high Ulawun volcano is unvegetated. A prominent E-W-trending escarpment on the south may be the result of large-scale slumping. Satellitic cones occupy the NW and eastern flanks. A steep-walled valley cuts the NW side of Ulawun volcano, and a flank lava-flow complex lies to the south of this valley. Historical eruptions date back to the beginning of the 18th century. Twentieth-century eruptions were mildly explosive until 1967, but after 1970 several larger eruptions produced lava flows and basaltic pyroclastic flows, greatly modifying the summit crater.
Information Contacts: Melbourne Overseas Service.