Report on Ulawun (Papua New Guinea) — January 1988
Scientific Event Alert Network Bulletin, vol. 13, no. 1 (January 1988)
Managing Editor: Lindsay McClelland.
Ulawun (Papua New Guinea) Continued strong seismicity; vapor emission
Please cite this report as:
Global Volcanism Program, 1988. Report on Ulawun (Papua New Guinea). In: McClelland, L (ed.), Scientific Event Alert Network Bulletin, 13:1. Smithsonian Institution. http://dx.doi.org/10.5479/si.GVP.SEAN198801-252120.
Papua New Guinea
5.05°S, 151.33°E; summit elev. 2334 m
All times are local (unless otherwise noted)
The increased seismicity . . . continued through January. Usually, 300-500 small events were recorded/day. A period of sub-continuous tremor began 20 January and lasted for ~27 hours. The summit crater emitted small to moderate amounts of white vapor during the few times that the summit was visible.
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: J. Mori and P. Lowenstein, RVO.