Report on Ulawun (Papua New Guinea) — September 1983
Scientific Event Alert Network Bulletin, vol. 8, no. 9 (September 1983)
Managing Editor: Lindsay McClelland
Ulawun (Papua New Guinea) Gas measurements on 11 September
Please cite this report as:
Global Volcanism Program, 1983. Report on Ulawun (Papua New Guinea). In: McClelland, L (ed.), Scientific Event Alert Network Bulletin, 8:9. Smithsonian Institution. http://dx.doi.org/10.5479/si.GVP.SEAN198309-252120.
Papua New Guinea
5.05°S, 151.33°E; summit elev. 2334 m
All times are local (unless otherwise noted)
[Richard Stoiber, Stanley Williams, and Chris McKee used a COSPEC to measure the rate of SO2 emission from several volcanoes in Papua New Guinea during September (table 1). Plumes at and Manam were strong, and plume was small. Activity at Langila was weak 11 September, but had intensified during measurements the next day. The quiet-phase data were collected from the ground; all other data were acquired while flying under the plumes.]
Table 1. Rates of SO2 emission at Bagana, Langila, Manam, and Ulawun, Papua New Guinea, September 1983. Airborne COSPEC data from R. Stoiber, S. Williams, and C. McKee.[Skip text table]
Volcano Date t/d SO2 Bagana 08 Sep 3,100 Langila 11 Sep 74 12 Sep 1,300 Manam 12 Sep 920 Ulawun 11 Sep 71
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: C. McKee, RVO; R. Stoiber and S. Williams, Dartmouth College.