Report on Ulawun (Papua New Guinea) — January 1986
Scientific Event Alert Network Bulletin, vol. 11, no. 1 (January 1986)
Managing Editor: Lindsay McClelland.
Ulawun (Papua New Guinea) Seismicity declines
Please cite this report as:
Global Volcanism Program, 1986. Report on Ulawun (Papua New Guinea) (McClelland, L., ed.). Scientific Event Alert Network Bulletin, 11:1. Smithsonian Institution. https://doi.org/10.5479/si.GVP.SEAN198601-252120
Papua New Guinea
5.05°S, 151.33°E; summit elev. 2334 m
All times are local (unless otherwise noted)
"In early January, seismicity at Ulawun was still declining (100-200 events/day), following the eruption in November 1985. On 22 January seismicity increased slightly to 300-500 events/day for 4 days then returned to previous levels. No significant visible activity was reported.
Geological Summary. 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. The volcano, also known as the Father, rises above the N coast of the island of New Britain across a low saddle NE of Bamus volcano, the South Son. The upper 1,000 m is unvegetated. A prominent E-W escarpment on the south may be the result of large-scale slumping. Satellitic cones occupy the NW and E flanks. A steep-walled valley cuts the NW side, 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: P. Lowenstein, RVO.